xref: /openbmc/linux/drivers/android/binder.c (revision 71df2cb2)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* binder.c
3  *
4  * Android IPC Subsystem
5  *
6  * Copyright (C) 2007-2008 Google, Inc.
7  */
8 
9 /*
10  * Locking overview
11  *
12  * There are 3 main spinlocks which must be acquired in the
13  * order shown:
14  *
15  * 1) proc->outer_lock : protects binder_ref
16  *    binder_proc_lock() and binder_proc_unlock() are
17  *    used to acq/rel.
18  * 2) node->lock : protects most fields of binder_node.
19  *    binder_node_lock() and binder_node_unlock() are
20  *    used to acq/rel
21  * 3) proc->inner_lock : protects the thread and node lists
22  *    (proc->threads, proc->waiting_threads, proc->nodes)
23  *    and all todo lists associated with the binder_proc
24  *    (proc->todo, thread->todo, proc->delivered_death and
25  *    node->async_todo), as well as thread->transaction_stack
26  *    binder_inner_proc_lock() and binder_inner_proc_unlock()
27  *    are used to acq/rel
28  *
29  * Any lock under procA must never be nested under any lock at the same
30  * level or below on procB.
31  *
32  * Functions that require a lock held on entry indicate which lock
33  * in the suffix of the function name:
34  *
35  * foo_olocked() : requires node->outer_lock
36  * foo_nlocked() : requires node->lock
37  * foo_ilocked() : requires proc->inner_lock
38  * foo_oilocked(): requires proc->outer_lock and proc->inner_lock
39  * foo_nilocked(): requires node->lock and proc->inner_lock
40  * ...
41  */
42 
43 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
44 
45 #include <linux/fdtable.h>
46 #include <linux/file.h>
47 #include <linux/freezer.h>
48 #include <linux/fs.h>
49 #include <linux/list.h>
50 #include <linux/miscdevice.h>
51 #include <linux/module.h>
52 #include <linux/mutex.h>
53 #include <linux/nsproxy.h>
54 #include <linux/poll.h>
55 #include <linux/debugfs.h>
56 #include <linux/rbtree.h>
57 #include <linux/sched/signal.h>
58 #include <linux/sched/mm.h>
59 #include <linux/seq_file.h>
60 #include <linux/string.h>
61 #include <linux/uaccess.h>
62 #include <linux/pid_namespace.h>
63 #include <linux/security.h>
64 #include <linux/spinlock.h>
65 #include <linux/ratelimit.h>
66 #include <linux/syscalls.h>
67 #include <linux/task_work.h>
68 #include <linux/sizes.h>
69 #include <linux/ktime.h>
70 
71 #include <uapi/linux/android/binder.h>
72 
73 #include <linux/cacheflush.h>
74 
75 #include "binder_internal.h"
76 #include "binder_trace.h"
77 
78 static HLIST_HEAD(binder_deferred_list);
79 static DEFINE_MUTEX(binder_deferred_lock);
80 
81 static HLIST_HEAD(binder_devices);
82 static HLIST_HEAD(binder_procs);
83 static DEFINE_MUTEX(binder_procs_lock);
84 
85 static HLIST_HEAD(binder_dead_nodes);
86 static DEFINE_SPINLOCK(binder_dead_nodes_lock);
87 
88 static struct dentry *binder_debugfs_dir_entry_root;
89 static struct dentry *binder_debugfs_dir_entry_proc;
90 static atomic_t binder_last_id;
91 
92 static int proc_show(struct seq_file *m, void *unused);
93 DEFINE_SHOW_ATTRIBUTE(proc);
94 
95 #define FORBIDDEN_MMAP_FLAGS                (VM_WRITE)
96 
97 enum {
98 	BINDER_DEBUG_USER_ERROR             = 1U << 0,
99 	BINDER_DEBUG_FAILED_TRANSACTION     = 1U << 1,
100 	BINDER_DEBUG_DEAD_TRANSACTION       = 1U << 2,
101 	BINDER_DEBUG_OPEN_CLOSE             = 1U << 3,
102 	BINDER_DEBUG_DEAD_BINDER            = 1U << 4,
103 	BINDER_DEBUG_DEATH_NOTIFICATION     = 1U << 5,
104 	BINDER_DEBUG_READ_WRITE             = 1U << 6,
105 	BINDER_DEBUG_USER_REFS              = 1U << 7,
106 	BINDER_DEBUG_THREADS                = 1U << 8,
107 	BINDER_DEBUG_TRANSACTION            = 1U << 9,
108 	BINDER_DEBUG_TRANSACTION_COMPLETE   = 1U << 10,
109 	BINDER_DEBUG_FREE_BUFFER            = 1U << 11,
110 	BINDER_DEBUG_INTERNAL_REFS          = 1U << 12,
111 	BINDER_DEBUG_PRIORITY_CAP           = 1U << 13,
112 	BINDER_DEBUG_SPINLOCKS              = 1U << 14,
113 };
114 static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR |
115 	BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION;
116 module_param_named(debug_mask, binder_debug_mask, uint, 0644);
117 
118 char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES;
119 module_param_named(devices, binder_devices_param, charp, 0444);
120 
121 static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait);
122 static int binder_stop_on_user_error;
123 
binder_set_stop_on_user_error(const char * val,const struct kernel_param * kp)124 static int binder_set_stop_on_user_error(const char *val,
125 					 const struct kernel_param *kp)
126 {
127 	int ret;
128 
129 	ret = param_set_int(val, kp);
130 	if (binder_stop_on_user_error < 2)
131 		wake_up(&binder_user_error_wait);
132 	return ret;
133 }
134 module_param_call(stop_on_user_error, binder_set_stop_on_user_error,
135 	param_get_int, &binder_stop_on_user_error, 0644);
136 
binder_debug(int mask,const char * format,...)137 static __printf(2, 3) void binder_debug(int mask, const char *format, ...)
138 {
139 	struct va_format vaf;
140 	va_list args;
141 
142 	if (binder_debug_mask & mask) {
143 		va_start(args, format);
144 		vaf.va = &args;
145 		vaf.fmt = format;
146 		pr_info_ratelimited("%pV", &vaf);
147 		va_end(args);
148 	}
149 }
150 
151 #define binder_txn_error(x...) \
152 	binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, x)
153 
binder_user_error(const char * format,...)154 static __printf(1, 2) void binder_user_error(const char *format, ...)
155 {
156 	struct va_format vaf;
157 	va_list args;
158 
159 	if (binder_debug_mask & BINDER_DEBUG_USER_ERROR) {
160 		va_start(args, format);
161 		vaf.va = &args;
162 		vaf.fmt = format;
163 		pr_info_ratelimited("%pV", &vaf);
164 		va_end(args);
165 	}
166 
167 	if (binder_stop_on_user_error)
168 		binder_stop_on_user_error = 2;
169 }
170 
171 #define binder_set_extended_error(ee, _id, _command, _param) \
172 	do { \
173 		(ee)->id = _id; \
174 		(ee)->command = _command; \
175 		(ee)->param = _param; \
176 	} while (0)
177 
178 #define to_flat_binder_object(hdr) \
179 	container_of(hdr, struct flat_binder_object, hdr)
180 
181 #define to_binder_fd_object(hdr) container_of(hdr, struct binder_fd_object, hdr)
182 
183 #define to_binder_buffer_object(hdr) \
184 	container_of(hdr, struct binder_buffer_object, hdr)
185 
186 #define to_binder_fd_array_object(hdr) \
187 	container_of(hdr, struct binder_fd_array_object, hdr)
188 
189 static struct binder_stats binder_stats;
190 
binder_stats_deleted(enum binder_stat_types type)191 static inline void binder_stats_deleted(enum binder_stat_types type)
192 {
193 	atomic_inc(&binder_stats.obj_deleted[type]);
194 }
195 
binder_stats_created(enum binder_stat_types type)196 static inline void binder_stats_created(enum binder_stat_types type)
197 {
198 	atomic_inc(&binder_stats.obj_created[type]);
199 }
200 
201 struct binder_transaction_log_entry {
202 	int debug_id;
203 	int debug_id_done;
204 	int call_type;
205 	int from_proc;
206 	int from_thread;
207 	int target_handle;
208 	int to_proc;
209 	int to_thread;
210 	int to_node;
211 	int data_size;
212 	int offsets_size;
213 	int return_error_line;
214 	uint32_t return_error;
215 	uint32_t return_error_param;
216 	char context_name[BINDERFS_MAX_NAME + 1];
217 };
218 
219 struct binder_transaction_log {
220 	atomic_t cur;
221 	bool full;
222 	struct binder_transaction_log_entry entry[32];
223 };
224 
225 static struct binder_transaction_log binder_transaction_log;
226 static struct binder_transaction_log binder_transaction_log_failed;
227 
binder_transaction_log_add(struct binder_transaction_log * log)228 static struct binder_transaction_log_entry *binder_transaction_log_add(
229 	struct binder_transaction_log *log)
230 {
231 	struct binder_transaction_log_entry *e;
232 	unsigned int cur = atomic_inc_return(&log->cur);
233 
234 	if (cur >= ARRAY_SIZE(log->entry))
235 		log->full = true;
236 	e = &log->entry[cur % ARRAY_SIZE(log->entry)];
237 	WRITE_ONCE(e->debug_id_done, 0);
238 	/*
239 	 * write-barrier to synchronize access to e->debug_id_done.
240 	 * We make sure the initialized 0 value is seen before
241 	 * memset() other fields are zeroed by memset.
242 	 */
243 	smp_wmb();
244 	memset(e, 0, sizeof(*e));
245 	return e;
246 }
247 
248 enum binder_deferred_state {
249 	BINDER_DEFERRED_FLUSH        = 0x01,
250 	BINDER_DEFERRED_RELEASE      = 0x02,
251 };
252 
253 enum {
254 	BINDER_LOOPER_STATE_REGISTERED  = 0x01,
255 	BINDER_LOOPER_STATE_ENTERED     = 0x02,
256 	BINDER_LOOPER_STATE_EXITED      = 0x04,
257 	BINDER_LOOPER_STATE_INVALID     = 0x08,
258 	BINDER_LOOPER_STATE_WAITING     = 0x10,
259 	BINDER_LOOPER_STATE_POLL        = 0x20,
260 };
261 
262 /**
263  * binder_proc_lock() - Acquire outer lock for given binder_proc
264  * @proc:         struct binder_proc to acquire
265  *
266  * Acquires proc->outer_lock. Used to protect binder_ref
267  * structures associated with the given proc.
268  */
269 #define binder_proc_lock(proc) _binder_proc_lock(proc, __LINE__)
270 static void
_binder_proc_lock(struct binder_proc * proc,int line)271 _binder_proc_lock(struct binder_proc *proc, int line)
272 	__acquires(&proc->outer_lock)
273 {
274 	binder_debug(BINDER_DEBUG_SPINLOCKS,
275 		     "%s: line=%d\n", __func__, line);
276 	spin_lock(&proc->outer_lock);
277 }
278 
279 /**
280  * binder_proc_unlock() - Release spinlock for given binder_proc
281  * @proc:                struct binder_proc to acquire
282  *
283  * Release lock acquired via binder_proc_lock()
284  */
285 #define binder_proc_unlock(proc) _binder_proc_unlock(proc, __LINE__)
286 static void
_binder_proc_unlock(struct binder_proc * proc,int line)287 _binder_proc_unlock(struct binder_proc *proc, int line)
288 	__releases(&proc->outer_lock)
289 {
290 	binder_debug(BINDER_DEBUG_SPINLOCKS,
291 		     "%s: line=%d\n", __func__, line);
292 	spin_unlock(&proc->outer_lock);
293 }
294 
295 /**
296  * binder_inner_proc_lock() - Acquire inner lock for given binder_proc
297  * @proc:         struct binder_proc to acquire
298  *
299  * Acquires proc->inner_lock. Used to protect todo lists
300  */
301 #define binder_inner_proc_lock(proc) _binder_inner_proc_lock(proc, __LINE__)
302 static void
_binder_inner_proc_lock(struct binder_proc * proc,int line)303 _binder_inner_proc_lock(struct binder_proc *proc, int line)
304 	__acquires(&proc->inner_lock)
305 {
306 	binder_debug(BINDER_DEBUG_SPINLOCKS,
307 		     "%s: line=%d\n", __func__, line);
308 	spin_lock(&proc->inner_lock);
309 }
310 
311 /**
312  * binder_inner_proc_unlock() - Release inner lock for given binder_proc
313  * @proc:         struct binder_proc to acquire
314  *
315  * Release lock acquired via binder_inner_proc_lock()
316  */
317 #define binder_inner_proc_unlock(proc) _binder_inner_proc_unlock(proc, __LINE__)
318 static void
_binder_inner_proc_unlock(struct binder_proc * proc,int line)319 _binder_inner_proc_unlock(struct binder_proc *proc, int line)
320 	__releases(&proc->inner_lock)
321 {
322 	binder_debug(BINDER_DEBUG_SPINLOCKS,
323 		     "%s: line=%d\n", __func__, line);
324 	spin_unlock(&proc->inner_lock);
325 }
326 
327 /**
328  * binder_node_lock() - Acquire spinlock for given binder_node
329  * @node:         struct binder_node to acquire
330  *
331  * Acquires node->lock. Used to protect binder_node fields
332  */
333 #define binder_node_lock(node) _binder_node_lock(node, __LINE__)
334 static void
_binder_node_lock(struct binder_node * node,int line)335 _binder_node_lock(struct binder_node *node, int line)
336 	__acquires(&node->lock)
337 {
338 	binder_debug(BINDER_DEBUG_SPINLOCKS,
339 		     "%s: line=%d\n", __func__, line);
340 	spin_lock(&node->lock);
341 }
342 
343 /**
344  * binder_node_unlock() - Release spinlock for given binder_proc
345  * @node:         struct binder_node to acquire
346  *
347  * Release lock acquired via binder_node_lock()
348  */
349 #define binder_node_unlock(node) _binder_node_unlock(node, __LINE__)
350 static void
_binder_node_unlock(struct binder_node * node,int line)351 _binder_node_unlock(struct binder_node *node, int line)
352 	__releases(&node->lock)
353 {
354 	binder_debug(BINDER_DEBUG_SPINLOCKS,
355 		     "%s: line=%d\n", __func__, line);
356 	spin_unlock(&node->lock);
357 }
358 
359 /**
360  * binder_node_inner_lock() - Acquire node and inner locks
361  * @node:         struct binder_node to acquire
362  *
363  * Acquires node->lock. If node->proc also acquires
364  * proc->inner_lock. Used to protect binder_node fields
365  */
366 #define binder_node_inner_lock(node) _binder_node_inner_lock(node, __LINE__)
367 static void
_binder_node_inner_lock(struct binder_node * node,int line)368 _binder_node_inner_lock(struct binder_node *node, int line)
369 	__acquires(&node->lock) __acquires(&node->proc->inner_lock)
370 {
371 	binder_debug(BINDER_DEBUG_SPINLOCKS,
372 		     "%s: line=%d\n", __func__, line);
373 	spin_lock(&node->lock);
374 	if (node->proc)
375 		binder_inner_proc_lock(node->proc);
376 	else
377 		/* annotation for sparse */
378 		__acquire(&node->proc->inner_lock);
379 }
380 
381 /**
382  * binder_node_inner_unlock() - Release node and inner locks
383  * @node:         struct binder_node to acquire
384  *
385  * Release lock acquired via binder_node_lock()
386  */
387 #define binder_node_inner_unlock(node) _binder_node_inner_unlock(node, __LINE__)
388 static void
_binder_node_inner_unlock(struct binder_node * node,int line)389 _binder_node_inner_unlock(struct binder_node *node, int line)
390 	__releases(&node->lock) __releases(&node->proc->inner_lock)
391 {
392 	struct binder_proc *proc = node->proc;
393 
394 	binder_debug(BINDER_DEBUG_SPINLOCKS,
395 		     "%s: line=%d\n", __func__, line);
396 	if (proc)
397 		binder_inner_proc_unlock(proc);
398 	else
399 		/* annotation for sparse */
400 		__release(&node->proc->inner_lock);
401 	spin_unlock(&node->lock);
402 }
403 
binder_worklist_empty_ilocked(struct list_head * list)404 static bool binder_worklist_empty_ilocked(struct list_head *list)
405 {
406 	return list_empty(list);
407 }
408 
409 /**
410  * binder_worklist_empty() - Check if no items on the work list
411  * @proc:       binder_proc associated with list
412  * @list:	list to check
413  *
414  * Return: true if there are no items on list, else false
415  */
binder_worklist_empty(struct binder_proc * proc,struct list_head * list)416 static bool binder_worklist_empty(struct binder_proc *proc,
417 				  struct list_head *list)
418 {
419 	bool ret;
420 
421 	binder_inner_proc_lock(proc);
422 	ret = binder_worklist_empty_ilocked(list);
423 	binder_inner_proc_unlock(proc);
424 	return ret;
425 }
426 
427 /**
428  * binder_enqueue_work_ilocked() - Add an item to the work list
429  * @work:         struct binder_work to add to list
430  * @target_list:  list to add work to
431  *
432  * Adds the work to the specified list. Asserts that work
433  * is not already on a list.
434  *
435  * Requires the proc->inner_lock to be held.
436  */
437 static void
binder_enqueue_work_ilocked(struct binder_work * work,struct list_head * target_list)438 binder_enqueue_work_ilocked(struct binder_work *work,
439 			   struct list_head *target_list)
440 {
441 	BUG_ON(target_list == NULL);
442 	BUG_ON(work->entry.next && !list_empty(&work->entry));
443 	list_add_tail(&work->entry, target_list);
444 }
445 
446 /**
447  * binder_enqueue_deferred_thread_work_ilocked() - Add deferred thread work
448  * @thread:       thread to queue work to
449  * @work:         struct binder_work to add to list
450  *
451  * Adds the work to the todo list of the thread. Doesn't set the process_todo
452  * flag, which means that (if it wasn't already set) the thread will go to
453  * sleep without handling this work when it calls read.
454  *
455  * Requires the proc->inner_lock to be held.
456  */
457 static void
binder_enqueue_deferred_thread_work_ilocked(struct binder_thread * thread,struct binder_work * work)458 binder_enqueue_deferred_thread_work_ilocked(struct binder_thread *thread,
459 					    struct binder_work *work)
460 {
461 	WARN_ON(!list_empty(&thread->waiting_thread_node));
462 	binder_enqueue_work_ilocked(work, &thread->todo);
463 }
464 
465 /**
466  * binder_enqueue_thread_work_ilocked() - Add an item to the thread work list
467  * @thread:       thread to queue work to
468  * @work:         struct binder_work to add to list
469  *
470  * Adds the work to the todo list of the thread, and enables processing
471  * of the todo queue.
472  *
473  * Requires the proc->inner_lock to be held.
474  */
475 static void
binder_enqueue_thread_work_ilocked(struct binder_thread * thread,struct binder_work * work)476 binder_enqueue_thread_work_ilocked(struct binder_thread *thread,
477 				   struct binder_work *work)
478 {
479 	WARN_ON(!list_empty(&thread->waiting_thread_node));
480 	binder_enqueue_work_ilocked(work, &thread->todo);
481 
482 	/* (e)poll-based threads require an explicit wakeup signal when
483 	 * queuing their own work; they rely on these events to consume
484 	 * messages without I/O block. Without it, threads risk waiting
485 	 * indefinitely without handling the work.
486 	 */
487 	if (thread->looper & BINDER_LOOPER_STATE_POLL &&
488 	    thread->pid == current->pid && !thread->process_todo)
489 		wake_up_interruptible_sync(&thread->wait);
490 
491 	thread->process_todo = true;
492 }
493 
494 /**
495  * binder_enqueue_thread_work() - Add an item to the thread work list
496  * @thread:       thread to queue work to
497  * @work:         struct binder_work to add to list
498  *
499  * Adds the work to the todo list of the thread, and enables processing
500  * of the todo queue.
501  */
502 static void
binder_enqueue_thread_work(struct binder_thread * thread,struct binder_work * work)503 binder_enqueue_thread_work(struct binder_thread *thread,
504 			   struct binder_work *work)
505 {
506 	binder_inner_proc_lock(thread->proc);
507 	binder_enqueue_thread_work_ilocked(thread, work);
508 	binder_inner_proc_unlock(thread->proc);
509 }
510 
511 static void
binder_dequeue_work_ilocked(struct binder_work * work)512 binder_dequeue_work_ilocked(struct binder_work *work)
513 {
514 	list_del_init(&work->entry);
515 }
516 
517 /**
518  * binder_dequeue_work() - Removes an item from the work list
519  * @proc:         binder_proc associated with list
520  * @work:         struct binder_work to remove from list
521  *
522  * Removes the specified work item from whatever list it is on.
523  * Can safely be called if work is not on any list.
524  */
525 static void
binder_dequeue_work(struct binder_proc * proc,struct binder_work * work)526 binder_dequeue_work(struct binder_proc *proc, struct binder_work *work)
527 {
528 	binder_inner_proc_lock(proc);
529 	binder_dequeue_work_ilocked(work);
530 	binder_inner_proc_unlock(proc);
531 }
532 
binder_dequeue_work_head_ilocked(struct list_head * list)533 static struct binder_work *binder_dequeue_work_head_ilocked(
534 					struct list_head *list)
535 {
536 	struct binder_work *w;
537 
538 	w = list_first_entry_or_null(list, struct binder_work, entry);
539 	if (w)
540 		list_del_init(&w->entry);
541 	return w;
542 }
543 
544 static void
545 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer);
546 static void binder_free_thread(struct binder_thread *thread);
547 static void binder_free_proc(struct binder_proc *proc);
548 static void binder_inc_node_tmpref_ilocked(struct binder_node *node);
549 
binder_has_work_ilocked(struct binder_thread * thread,bool do_proc_work)550 static bool binder_has_work_ilocked(struct binder_thread *thread,
551 				    bool do_proc_work)
552 {
553 	return thread->process_todo ||
554 		thread->looper_need_return ||
555 		(do_proc_work &&
556 		 !binder_worklist_empty_ilocked(&thread->proc->todo));
557 }
558 
binder_has_work(struct binder_thread * thread,bool do_proc_work)559 static bool binder_has_work(struct binder_thread *thread, bool do_proc_work)
560 {
561 	bool has_work;
562 
563 	binder_inner_proc_lock(thread->proc);
564 	has_work = binder_has_work_ilocked(thread, do_proc_work);
565 	binder_inner_proc_unlock(thread->proc);
566 
567 	return has_work;
568 }
569 
binder_available_for_proc_work_ilocked(struct binder_thread * thread)570 static bool binder_available_for_proc_work_ilocked(struct binder_thread *thread)
571 {
572 	return !thread->transaction_stack &&
573 		binder_worklist_empty_ilocked(&thread->todo) &&
574 		(thread->looper & (BINDER_LOOPER_STATE_ENTERED |
575 				   BINDER_LOOPER_STATE_REGISTERED));
576 }
577 
binder_wakeup_poll_threads_ilocked(struct binder_proc * proc,bool sync)578 static void binder_wakeup_poll_threads_ilocked(struct binder_proc *proc,
579 					       bool sync)
580 {
581 	struct rb_node *n;
582 	struct binder_thread *thread;
583 
584 	for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
585 		thread = rb_entry(n, struct binder_thread, rb_node);
586 		if (thread->looper & BINDER_LOOPER_STATE_POLL &&
587 		    binder_available_for_proc_work_ilocked(thread)) {
588 			if (sync)
589 				wake_up_interruptible_sync(&thread->wait);
590 			else
591 				wake_up_interruptible(&thread->wait);
592 		}
593 	}
594 }
595 
596 /**
597  * binder_select_thread_ilocked() - selects a thread for doing proc work.
598  * @proc:	process to select a thread from
599  *
600  * Note that calling this function moves the thread off the waiting_threads
601  * list, so it can only be woken up by the caller of this function, or a
602  * signal. Therefore, callers *should* always wake up the thread this function
603  * returns.
604  *
605  * Return:	If there's a thread currently waiting for process work,
606  *		returns that thread. Otherwise returns NULL.
607  */
608 static struct binder_thread *
binder_select_thread_ilocked(struct binder_proc * proc)609 binder_select_thread_ilocked(struct binder_proc *proc)
610 {
611 	struct binder_thread *thread;
612 
613 	assert_spin_locked(&proc->inner_lock);
614 	thread = list_first_entry_or_null(&proc->waiting_threads,
615 					  struct binder_thread,
616 					  waiting_thread_node);
617 
618 	if (thread)
619 		list_del_init(&thread->waiting_thread_node);
620 
621 	return thread;
622 }
623 
624 /**
625  * binder_wakeup_thread_ilocked() - wakes up a thread for doing proc work.
626  * @proc:	process to wake up a thread in
627  * @thread:	specific thread to wake-up (may be NULL)
628  * @sync:	whether to do a synchronous wake-up
629  *
630  * This function wakes up a thread in the @proc process.
631  * The caller may provide a specific thread to wake-up in
632  * the @thread parameter. If @thread is NULL, this function
633  * will wake up threads that have called poll().
634  *
635  * Note that for this function to work as expected, callers
636  * should first call binder_select_thread() to find a thread
637  * to handle the work (if they don't have a thread already),
638  * and pass the result into the @thread parameter.
639  */
binder_wakeup_thread_ilocked(struct binder_proc * proc,struct binder_thread * thread,bool sync)640 static void binder_wakeup_thread_ilocked(struct binder_proc *proc,
641 					 struct binder_thread *thread,
642 					 bool sync)
643 {
644 	assert_spin_locked(&proc->inner_lock);
645 
646 	if (thread) {
647 		if (sync)
648 			wake_up_interruptible_sync(&thread->wait);
649 		else
650 			wake_up_interruptible(&thread->wait);
651 		return;
652 	}
653 
654 	/* Didn't find a thread waiting for proc work; this can happen
655 	 * in two scenarios:
656 	 * 1. All threads are busy handling transactions
657 	 *    In that case, one of those threads should call back into
658 	 *    the kernel driver soon and pick up this work.
659 	 * 2. Threads are using the (e)poll interface, in which case
660 	 *    they may be blocked on the waitqueue without having been
661 	 *    added to waiting_threads. For this case, we just iterate
662 	 *    over all threads not handling transaction work, and
663 	 *    wake them all up. We wake all because we don't know whether
664 	 *    a thread that called into (e)poll is handling non-binder
665 	 *    work currently.
666 	 */
667 	binder_wakeup_poll_threads_ilocked(proc, sync);
668 }
669 
binder_wakeup_proc_ilocked(struct binder_proc * proc)670 static void binder_wakeup_proc_ilocked(struct binder_proc *proc)
671 {
672 	struct binder_thread *thread = binder_select_thread_ilocked(proc);
673 
674 	binder_wakeup_thread_ilocked(proc, thread, /* sync = */false);
675 }
676 
binder_set_nice(long nice)677 static void binder_set_nice(long nice)
678 {
679 	long min_nice;
680 
681 	if (can_nice(current, nice)) {
682 		set_user_nice(current, nice);
683 		return;
684 	}
685 	min_nice = rlimit_to_nice(rlimit(RLIMIT_NICE));
686 	binder_debug(BINDER_DEBUG_PRIORITY_CAP,
687 		     "%d: nice value %ld not allowed use %ld instead\n",
688 		      current->pid, nice, min_nice);
689 	set_user_nice(current, min_nice);
690 	if (min_nice <= MAX_NICE)
691 		return;
692 	binder_user_error("%d RLIMIT_NICE not set\n", current->pid);
693 }
694 
binder_get_node_ilocked(struct binder_proc * proc,binder_uintptr_t ptr)695 static struct binder_node *binder_get_node_ilocked(struct binder_proc *proc,
696 						   binder_uintptr_t ptr)
697 {
698 	struct rb_node *n = proc->nodes.rb_node;
699 	struct binder_node *node;
700 
701 	assert_spin_locked(&proc->inner_lock);
702 
703 	while (n) {
704 		node = rb_entry(n, struct binder_node, rb_node);
705 
706 		if (ptr < node->ptr)
707 			n = n->rb_left;
708 		else if (ptr > node->ptr)
709 			n = n->rb_right;
710 		else {
711 			/*
712 			 * take an implicit weak reference
713 			 * to ensure node stays alive until
714 			 * call to binder_put_node()
715 			 */
716 			binder_inc_node_tmpref_ilocked(node);
717 			return node;
718 		}
719 	}
720 	return NULL;
721 }
722 
binder_get_node(struct binder_proc * proc,binder_uintptr_t ptr)723 static struct binder_node *binder_get_node(struct binder_proc *proc,
724 					   binder_uintptr_t ptr)
725 {
726 	struct binder_node *node;
727 
728 	binder_inner_proc_lock(proc);
729 	node = binder_get_node_ilocked(proc, ptr);
730 	binder_inner_proc_unlock(proc);
731 	return node;
732 }
733 
binder_init_node_ilocked(struct binder_proc * proc,struct binder_node * new_node,struct flat_binder_object * fp)734 static struct binder_node *binder_init_node_ilocked(
735 						struct binder_proc *proc,
736 						struct binder_node *new_node,
737 						struct flat_binder_object *fp)
738 {
739 	struct rb_node **p = &proc->nodes.rb_node;
740 	struct rb_node *parent = NULL;
741 	struct binder_node *node;
742 	binder_uintptr_t ptr = fp ? fp->binder : 0;
743 	binder_uintptr_t cookie = fp ? fp->cookie : 0;
744 	__u32 flags = fp ? fp->flags : 0;
745 
746 	assert_spin_locked(&proc->inner_lock);
747 
748 	while (*p) {
749 
750 		parent = *p;
751 		node = rb_entry(parent, struct binder_node, rb_node);
752 
753 		if (ptr < node->ptr)
754 			p = &(*p)->rb_left;
755 		else if (ptr > node->ptr)
756 			p = &(*p)->rb_right;
757 		else {
758 			/*
759 			 * A matching node is already in
760 			 * the rb tree. Abandon the init
761 			 * and return it.
762 			 */
763 			binder_inc_node_tmpref_ilocked(node);
764 			return node;
765 		}
766 	}
767 	node = new_node;
768 	binder_stats_created(BINDER_STAT_NODE);
769 	node->tmp_refs++;
770 	rb_link_node(&node->rb_node, parent, p);
771 	rb_insert_color(&node->rb_node, &proc->nodes);
772 	node->debug_id = atomic_inc_return(&binder_last_id);
773 	node->proc = proc;
774 	node->ptr = ptr;
775 	node->cookie = cookie;
776 	node->work.type = BINDER_WORK_NODE;
777 	node->min_priority = flags & FLAT_BINDER_FLAG_PRIORITY_MASK;
778 	node->accept_fds = !!(flags & FLAT_BINDER_FLAG_ACCEPTS_FDS);
779 	node->txn_security_ctx = !!(flags & FLAT_BINDER_FLAG_TXN_SECURITY_CTX);
780 	spin_lock_init(&node->lock);
781 	INIT_LIST_HEAD(&node->work.entry);
782 	INIT_LIST_HEAD(&node->async_todo);
783 	binder_debug(BINDER_DEBUG_INTERNAL_REFS,
784 		     "%d:%d node %d u%016llx c%016llx created\n",
785 		     proc->pid, current->pid, node->debug_id,
786 		     (u64)node->ptr, (u64)node->cookie);
787 
788 	return node;
789 }
790 
binder_new_node(struct binder_proc * proc,struct flat_binder_object * fp)791 static struct binder_node *binder_new_node(struct binder_proc *proc,
792 					   struct flat_binder_object *fp)
793 {
794 	struct binder_node *node;
795 	struct binder_node *new_node = kzalloc(sizeof(*node), GFP_KERNEL);
796 
797 	if (!new_node)
798 		return NULL;
799 	binder_inner_proc_lock(proc);
800 	node = binder_init_node_ilocked(proc, new_node, fp);
801 	binder_inner_proc_unlock(proc);
802 	if (node != new_node)
803 		/*
804 		 * The node was already added by another thread
805 		 */
806 		kfree(new_node);
807 
808 	return node;
809 }
810 
binder_free_node(struct binder_node * node)811 static void binder_free_node(struct binder_node *node)
812 {
813 	kfree(node);
814 	binder_stats_deleted(BINDER_STAT_NODE);
815 }
816 
binder_inc_node_nilocked(struct binder_node * node,int strong,int internal,struct list_head * target_list)817 static int binder_inc_node_nilocked(struct binder_node *node, int strong,
818 				    int internal,
819 				    struct list_head *target_list)
820 {
821 	struct binder_proc *proc = node->proc;
822 
823 	assert_spin_locked(&node->lock);
824 	if (proc)
825 		assert_spin_locked(&proc->inner_lock);
826 	if (strong) {
827 		if (internal) {
828 			if (target_list == NULL &&
829 			    node->internal_strong_refs == 0 &&
830 			    !(node->proc &&
831 			      node == node->proc->context->binder_context_mgr_node &&
832 			      node->has_strong_ref)) {
833 				pr_err("invalid inc strong node for %d\n",
834 					node->debug_id);
835 				return -EINVAL;
836 			}
837 			node->internal_strong_refs++;
838 		} else
839 			node->local_strong_refs++;
840 		if (!node->has_strong_ref && target_list) {
841 			struct binder_thread *thread = container_of(target_list,
842 						    struct binder_thread, todo);
843 			binder_dequeue_work_ilocked(&node->work);
844 			BUG_ON(&thread->todo != target_list);
845 			binder_enqueue_deferred_thread_work_ilocked(thread,
846 								   &node->work);
847 		}
848 	} else {
849 		if (!internal)
850 			node->local_weak_refs++;
851 		if (!node->has_weak_ref && list_empty(&node->work.entry)) {
852 			if (target_list == NULL) {
853 				pr_err("invalid inc weak node for %d\n",
854 					node->debug_id);
855 				return -EINVAL;
856 			}
857 			/*
858 			 * See comment above
859 			 */
860 			binder_enqueue_work_ilocked(&node->work, target_list);
861 		}
862 	}
863 	return 0;
864 }
865 
binder_inc_node(struct binder_node * node,int strong,int internal,struct list_head * target_list)866 static int binder_inc_node(struct binder_node *node, int strong, int internal,
867 			   struct list_head *target_list)
868 {
869 	int ret;
870 
871 	binder_node_inner_lock(node);
872 	ret = binder_inc_node_nilocked(node, strong, internal, target_list);
873 	binder_node_inner_unlock(node);
874 
875 	return ret;
876 }
877 
binder_dec_node_nilocked(struct binder_node * node,int strong,int internal)878 static bool binder_dec_node_nilocked(struct binder_node *node,
879 				     int strong, int internal)
880 {
881 	struct binder_proc *proc = node->proc;
882 
883 	assert_spin_locked(&node->lock);
884 	if (proc)
885 		assert_spin_locked(&proc->inner_lock);
886 	if (strong) {
887 		if (internal)
888 			node->internal_strong_refs--;
889 		else
890 			node->local_strong_refs--;
891 		if (node->local_strong_refs || node->internal_strong_refs)
892 			return false;
893 	} else {
894 		if (!internal)
895 			node->local_weak_refs--;
896 		if (node->local_weak_refs || node->tmp_refs ||
897 				!hlist_empty(&node->refs))
898 			return false;
899 	}
900 
901 	if (proc && (node->has_strong_ref || node->has_weak_ref)) {
902 		if (list_empty(&node->work.entry)) {
903 			binder_enqueue_work_ilocked(&node->work, &proc->todo);
904 			binder_wakeup_proc_ilocked(proc);
905 		}
906 	} else {
907 		if (hlist_empty(&node->refs) && !node->local_strong_refs &&
908 		    !node->local_weak_refs && !node->tmp_refs) {
909 			if (proc) {
910 				binder_dequeue_work_ilocked(&node->work);
911 				rb_erase(&node->rb_node, &proc->nodes);
912 				binder_debug(BINDER_DEBUG_INTERNAL_REFS,
913 					     "refless node %d deleted\n",
914 					     node->debug_id);
915 			} else {
916 				BUG_ON(!list_empty(&node->work.entry));
917 				spin_lock(&binder_dead_nodes_lock);
918 				/*
919 				 * tmp_refs could have changed so
920 				 * check it again
921 				 */
922 				if (node->tmp_refs) {
923 					spin_unlock(&binder_dead_nodes_lock);
924 					return false;
925 				}
926 				hlist_del(&node->dead_node);
927 				spin_unlock(&binder_dead_nodes_lock);
928 				binder_debug(BINDER_DEBUG_INTERNAL_REFS,
929 					     "dead node %d deleted\n",
930 					     node->debug_id);
931 			}
932 			return true;
933 		}
934 	}
935 	return false;
936 }
937 
binder_dec_node(struct binder_node * node,int strong,int internal)938 static void binder_dec_node(struct binder_node *node, int strong, int internal)
939 {
940 	bool free_node;
941 
942 	binder_node_inner_lock(node);
943 	free_node = binder_dec_node_nilocked(node, strong, internal);
944 	binder_node_inner_unlock(node);
945 	if (free_node)
946 		binder_free_node(node);
947 }
948 
binder_inc_node_tmpref_ilocked(struct binder_node * node)949 static void binder_inc_node_tmpref_ilocked(struct binder_node *node)
950 {
951 	/*
952 	 * No call to binder_inc_node() is needed since we
953 	 * don't need to inform userspace of any changes to
954 	 * tmp_refs
955 	 */
956 	node->tmp_refs++;
957 }
958 
959 /**
960  * binder_inc_node_tmpref() - take a temporary reference on node
961  * @node:	node to reference
962  *
963  * Take reference on node to prevent the node from being freed
964  * while referenced only by a local variable. The inner lock is
965  * needed to serialize with the node work on the queue (which
966  * isn't needed after the node is dead). If the node is dead
967  * (node->proc is NULL), use binder_dead_nodes_lock to protect
968  * node->tmp_refs against dead-node-only cases where the node
969  * lock cannot be acquired (eg traversing the dead node list to
970  * print nodes)
971  */
binder_inc_node_tmpref(struct binder_node * node)972 static void binder_inc_node_tmpref(struct binder_node *node)
973 {
974 	binder_node_lock(node);
975 	if (node->proc)
976 		binder_inner_proc_lock(node->proc);
977 	else
978 		spin_lock(&binder_dead_nodes_lock);
979 	binder_inc_node_tmpref_ilocked(node);
980 	if (node->proc)
981 		binder_inner_proc_unlock(node->proc);
982 	else
983 		spin_unlock(&binder_dead_nodes_lock);
984 	binder_node_unlock(node);
985 }
986 
987 /**
988  * binder_dec_node_tmpref() - remove a temporary reference on node
989  * @node:	node to reference
990  *
991  * Release temporary reference on node taken via binder_inc_node_tmpref()
992  */
binder_dec_node_tmpref(struct binder_node * node)993 static void binder_dec_node_tmpref(struct binder_node *node)
994 {
995 	bool free_node;
996 
997 	binder_node_inner_lock(node);
998 	if (!node->proc)
999 		spin_lock(&binder_dead_nodes_lock);
1000 	else
1001 		__acquire(&binder_dead_nodes_lock);
1002 	node->tmp_refs--;
1003 	BUG_ON(node->tmp_refs < 0);
1004 	if (!node->proc)
1005 		spin_unlock(&binder_dead_nodes_lock);
1006 	else
1007 		__release(&binder_dead_nodes_lock);
1008 	/*
1009 	 * Call binder_dec_node() to check if all refcounts are 0
1010 	 * and cleanup is needed. Calling with strong=0 and internal=1
1011 	 * causes no actual reference to be released in binder_dec_node().
1012 	 * If that changes, a change is needed here too.
1013 	 */
1014 	free_node = binder_dec_node_nilocked(node, 0, 1);
1015 	binder_node_inner_unlock(node);
1016 	if (free_node)
1017 		binder_free_node(node);
1018 }
1019 
binder_put_node(struct binder_node * node)1020 static void binder_put_node(struct binder_node *node)
1021 {
1022 	binder_dec_node_tmpref(node);
1023 }
1024 
binder_get_ref_olocked(struct binder_proc * proc,u32 desc,bool need_strong_ref)1025 static struct binder_ref *binder_get_ref_olocked(struct binder_proc *proc,
1026 						 u32 desc, bool need_strong_ref)
1027 {
1028 	struct rb_node *n = proc->refs_by_desc.rb_node;
1029 	struct binder_ref *ref;
1030 
1031 	while (n) {
1032 		ref = rb_entry(n, struct binder_ref, rb_node_desc);
1033 
1034 		if (desc < ref->data.desc) {
1035 			n = n->rb_left;
1036 		} else if (desc > ref->data.desc) {
1037 			n = n->rb_right;
1038 		} else if (need_strong_ref && !ref->data.strong) {
1039 			binder_user_error("tried to use weak ref as strong ref\n");
1040 			return NULL;
1041 		} else {
1042 			return ref;
1043 		}
1044 	}
1045 	return NULL;
1046 }
1047 
1048 /**
1049  * binder_get_ref_for_node_olocked() - get the ref associated with given node
1050  * @proc:	binder_proc that owns the ref
1051  * @node:	binder_node of target
1052  * @new_ref:	newly allocated binder_ref to be initialized or %NULL
1053  *
1054  * Look up the ref for the given node and return it if it exists
1055  *
1056  * If it doesn't exist and the caller provides a newly allocated
1057  * ref, initialize the fields of the newly allocated ref and insert
1058  * into the given proc rb_trees and node refs list.
1059  *
1060  * Return:	the ref for node. It is possible that another thread
1061  *		allocated/initialized the ref first in which case the
1062  *		returned ref would be different than the passed-in
1063  *		new_ref. new_ref must be kfree'd by the caller in
1064  *		this case.
1065  */
binder_get_ref_for_node_olocked(struct binder_proc * proc,struct binder_node * node,struct binder_ref * new_ref)1066 static struct binder_ref *binder_get_ref_for_node_olocked(
1067 					struct binder_proc *proc,
1068 					struct binder_node *node,
1069 					struct binder_ref *new_ref)
1070 {
1071 	struct binder_context *context = proc->context;
1072 	struct rb_node **p = &proc->refs_by_node.rb_node;
1073 	struct rb_node *parent = NULL;
1074 	struct binder_ref *ref;
1075 	struct rb_node *n;
1076 
1077 	while (*p) {
1078 		parent = *p;
1079 		ref = rb_entry(parent, struct binder_ref, rb_node_node);
1080 
1081 		if (node < ref->node)
1082 			p = &(*p)->rb_left;
1083 		else if (node > ref->node)
1084 			p = &(*p)->rb_right;
1085 		else
1086 			return ref;
1087 	}
1088 	if (!new_ref)
1089 		return NULL;
1090 
1091 	binder_stats_created(BINDER_STAT_REF);
1092 	new_ref->data.debug_id = atomic_inc_return(&binder_last_id);
1093 	new_ref->proc = proc;
1094 	new_ref->node = node;
1095 	rb_link_node(&new_ref->rb_node_node, parent, p);
1096 	rb_insert_color(&new_ref->rb_node_node, &proc->refs_by_node);
1097 
1098 	new_ref->data.desc = (node == context->binder_context_mgr_node) ? 0 : 1;
1099 	for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) {
1100 		ref = rb_entry(n, struct binder_ref, rb_node_desc);
1101 		if (ref->data.desc > new_ref->data.desc)
1102 			break;
1103 		new_ref->data.desc = ref->data.desc + 1;
1104 	}
1105 
1106 	p = &proc->refs_by_desc.rb_node;
1107 	while (*p) {
1108 		parent = *p;
1109 		ref = rb_entry(parent, struct binder_ref, rb_node_desc);
1110 
1111 		if (new_ref->data.desc < ref->data.desc)
1112 			p = &(*p)->rb_left;
1113 		else if (new_ref->data.desc > ref->data.desc)
1114 			p = &(*p)->rb_right;
1115 		else
1116 			BUG();
1117 	}
1118 	rb_link_node(&new_ref->rb_node_desc, parent, p);
1119 	rb_insert_color(&new_ref->rb_node_desc, &proc->refs_by_desc);
1120 
1121 	binder_node_lock(node);
1122 	hlist_add_head(&new_ref->node_entry, &node->refs);
1123 
1124 	binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1125 		     "%d new ref %d desc %d for node %d\n",
1126 		      proc->pid, new_ref->data.debug_id, new_ref->data.desc,
1127 		      node->debug_id);
1128 	binder_node_unlock(node);
1129 	return new_ref;
1130 }
1131 
binder_cleanup_ref_olocked(struct binder_ref * ref)1132 static void binder_cleanup_ref_olocked(struct binder_ref *ref)
1133 {
1134 	bool delete_node = false;
1135 
1136 	binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1137 		     "%d delete ref %d desc %d for node %d\n",
1138 		      ref->proc->pid, ref->data.debug_id, ref->data.desc,
1139 		      ref->node->debug_id);
1140 
1141 	rb_erase(&ref->rb_node_desc, &ref->proc->refs_by_desc);
1142 	rb_erase(&ref->rb_node_node, &ref->proc->refs_by_node);
1143 
1144 	binder_node_inner_lock(ref->node);
1145 	if (ref->data.strong)
1146 		binder_dec_node_nilocked(ref->node, 1, 1);
1147 
1148 	hlist_del(&ref->node_entry);
1149 	delete_node = binder_dec_node_nilocked(ref->node, 0, 1);
1150 	binder_node_inner_unlock(ref->node);
1151 	/*
1152 	 * Clear ref->node unless we want the caller to free the node
1153 	 */
1154 	if (!delete_node) {
1155 		/*
1156 		 * The caller uses ref->node to determine
1157 		 * whether the node needs to be freed. Clear
1158 		 * it since the node is still alive.
1159 		 */
1160 		ref->node = NULL;
1161 	}
1162 
1163 	if (ref->death) {
1164 		binder_debug(BINDER_DEBUG_DEAD_BINDER,
1165 			     "%d delete ref %d desc %d has death notification\n",
1166 			      ref->proc->pid, ref->data.debug_id,
1167 			      ref->data.desc);
1168 		binder_dequeue_work(ref->proc, &ref->death->work);
1169 		binder_stats_deleted(BINDER_STAT_DEATH);
1170 	}
1171 	binder_stats_deleted(BINDER_STAT_REF);
1172 }
1173 
1174 /**
1175  * binder_inc_ref_olocked() - increment the ref for given handle
1176  * @ref:         ref to be incremented
1177  * @strong:      if true, strong increment, else weak
1178  * @target_list: list to queue node work on
1179  *
1180  * Increment the ref. @ref->proc->outer_lock must be held on entry
1181  *
1182  * Return: 0, if successful, else errno
1183  */
binder_inc_ref_olocked(struct binder_ref * ref,int strong,struct list_head * target_list)1184 static int binder_inc_ref_olocked(struct binder_ref *ref, int strong,
1185 				  struct list_head *target_list)
1186 {
1187 	int ret;
1188 
1189 	if (strong) {
1190 		if (ref->data.strong == 0) {
1191 			ret = binder_inc_node(ref->node, 1, 1, target_list);
1192 			if (ret)
1193 				return ret;
1194 		}
1195 		ref->data.strong++;
1196 	} else {
1197 		if (ref->data.weak == 0) {
1198 			ret = binder_inc_node(ref->node, 0, 1, target_list);
1199 			if (ret)
1200 				return ret;
1201 		}
1202 		ref->data.weak++;
1203 	}
1204 	return 0;
1205 }
1206 
1207 /**
1208  * binder_dec_ref_olocked() - dec the ref for given handle
1209  * @ref:	ref to be decremented
1210  * @strong:	if true, strong decrement, else weak
1211  *
1212  * Decrement the ref.
1213  *
1214  * Return: %true if ref is cleaned up and ready to be freed.
1215  */
binder_dec_ref_olocked(struct binder_ref * ref,int strong)1216 static bool binder_dec_ref_olocked(struct binder_ref *ref, int strong)
1217 {
1218 	if (strong) {
1219 		if (ref->data.strong == 0) {
1220 			binder_user_error("%d invalid dec strong, ref %d desc %d s %d w %d\n",
1221 					  ref->proc->pid, ref->data.debug_id,
1222 					  ref->data.desc, ref->data.strong,
1223 					  ref->data.weak);
1224 			return false;
1225 		}
1226 		ref->data.strong--;
1227 		if (ref->data.strong == 0)
1228 			binder_dec_node(ref->node, strong, 1);
1229 	} else {
1230 		if (ref->data.weak == 0) {
1231 			binder_user_error("%d invalid dec weak, ref %d desc %d s %d w %d\n",
1232 					  ref->proc->pid, ref->data.debug_id,
1233 					  ref->data.desc, ref->data.strong,
1234 					  ref->data.weak);
1235 			return false;
1236 		}
1237 		ref->data.weak--;
1238 	}
1239 	if (ref->data.strong == 0 && ref->data.weak == 0) {
1240 		binder_cleanup_ref_olocked(ref);
1241 		return true;
1242 	}
1243 	return false;
1244 }
1245 
1246 /**
1247  * binder_get_node_from_ref() - get the node from the given proc/desc
1248  * @proc:	proc containing the ref
1249  * @desc:	the handle associated with the ref
1250  * @need_strong_ref: if true, only return node if ref is strong
1251  * @rdata:	the id/refcount data for the ref
1252  *
1253  * Given a proc and ref handle, return the associated binder_node
1254  *
1255  * Return: a binder_node or NULL if not found or not strong when strong required
1256  */
binder_get_node_from_ref(struct binder_proc * proc,u32 desc,bool need_strong_ref,struct binder_ref_data * rdata)1257 static struct binder_node *binder_get_node_from_ref(
1258 		struct binder_proc *proc,
1259 		u32 desc, bool need_strong_ref,
1260 		struct binder_ref_data *rdata)
1261 {
1262 	struct binder_node *node;
1263 	struct binder_ref *ref;
1264 
1265 	binder_proc_lock(proc);
1266 	ref = binder_get_ref_olocked(proc, desc, need_strong_ref);
1267 	if (!ref)
1268 		goto err_no_ref;
1269 	node = ref->node;
1270 	/*
1271 	 * Take an implicit reference on the node to ensure
1272 	 * it stays alive until the call to binder_put_node()
1273 	 */
1274 	binder_inc_node_tmpref(node);
1275 	if (rdata)
1276 		*rdata = ref->data;
1277 	binder_proc_unlock(proc);
1278 
1279 	return node;
1280 
1281 err_no_ref:
1282 	binder_proc_unlock(proc);
1283 	return NULL;
1284 }
1285 
1286 /**
1287  * binder_free_ref() - free the binder_ref
1288  * @ref:	ref to free
1289  *
1290  * Free the binder_ref. Free the binder_node indicated by ref->node
1291  * (if non-NULL) and the binder_ref_death indicated by ref->death.
1292  */
binder_free_ref(struct binder_ref * ref)1293 static void binder_free_ref(struct binder_ref *ref)
1294 {
1295 	if (ref->node)
1296 		binder_free_node(ref->node);
1297 	kfree(ref->death);
1298 	kfree(ref);
1299 }
1300 
1301 /**
1302  * binder_update_ref_for_handle() - inc/dec the ref for given handle
1303  * @proc:	proc containing the ref
1304  * @desc:	the handle associated with the ref
1305  * @increment:	true=inc reference, false=dec reference
1306  * @strong:	true=strong reference, false=weak reference
1307  * @rdata:	the id/refcount data for the ref
1308  *
1309  * Given a proc and ref handle, increment or decrement the ref
1310  * according to "increment" arg.
1311  *
1312  * Return: 0 if successful, else errno
1313  */
binder_update_ref_for_handle(struct binder_proc * proc,uint32_t desc,bool increment,bool strong,struct binder_ref_data * rdata)1314 static int binder_update_ref_for_handle(struct binder_proc *proc,
1315 		uint32_t desc, bool increment, bool strong,
1316 		struct binder_ref_data *rdata)
1317 {
1318 	int ret = 0;
1319 	struct binder_ref *ref;
1320 	bool delete_ref = false;
1321 
1322 	binder_proc_lock(proc);
1323 	ref = binder_get_ref_olocked(proc, desc, strong);
1324 	if (!ref) {
1325 		ret = -EINVAL;
1326 		goto err_no_ref;
1327 	}
1328 	if (increment)
1329 		ret = binder_inc_ref_olocked(ref, strong, NULL);
1330 	else
1331 		delete_ref = binder_dec_ref_olocked(ref, strong);
1332 
1333 	if (rdata)
1334 		*rdata = ref->data;
1335 	binder_proc_unlock(proc);
1336 
1337 	if (delete_ref)
1338 		binder_free_ref(ref);
1339 	return ret;
1340 
1341 err_no_ref:
1342 	binder_proc_unlock(proc);
1343 	return ret;
1344 }
1345 
1346 /**
1347  * binder_dec_ref_for_handle() - dec the ref for given handle
1348  * @proc:	proc containing the ref
1349  * @desc:	the handle associated with the ref
1350  * @strong:	true=strong reference, false=weak reference
1351  * @rdata:	the id/refcount data for the ref
1352  *
1353  * Just calls binder_update_ref_for_handle() to decrement the ref.
1354  *
1355  * Return: 0 if successful, else errno
1356  */
binder_dec_ref_for_handle(struct binder_proc * proc,uint32_t desc,bool strong,struct binder_ref_data * rdata)1357 static int binder_dec_ref_for_handle(struct binder_proc *proc,
1358 		uint32_t desc, bool strong, struct binder_ref_data *rdata)
1359 {
1360 	return binder_update_ref_for_handle(proc, desc, false, strong, rdata);
1361 }
1362 
1363 
1364 /**
1365  * binder_inc_ref_for_node() - increment the ref for given proc/node
1366  * @proc:	 proc containing the ref
1367  * @node:	 target node
1368  * @strong:	 true=strong reference, false=weak reference
1369  * @target_list: worklist to use if node is incremented
1370  * @rdata:	 the id/refcount data for the ref
1371  *
1372  * Given a proc and node, increment the ref. Create the ref if it
1373  * doesn't already exist
1374  *
1375  * Return: 0 if successful, else errno
1376  */
binder_inc_ref_for_node(struct binder_proc * proc,struct binder_node * node,bool strong,struct list_head * target_list,struct binder_ref_data * rdata)1377 static int binder_inc_ref_for_node(struct binder_proc *proc,
1378 			struct binder_node *node,
1379 			bool strong,
1380 			struct list_head *target_list,
1381 			struct binder_ref_data *rdata)
1382 {
1383 	struct binder_ref *ref;
1384 	struct binder_ref *new_ref = NULL;
1385 	int ret = 0;
1386 
1387 	binder_proc_lock(proc);
1388 	ref = binder_get_ref_for_node_olocked(proc, node, NULL);
1389 	if (!ref) {
1390 		binder_proc_unlock(proc);
1391 		new_ref = kzalloc(sizeof(*ref), GFP_KERNEL);
1392 		if (!new_ref)
1393 			return -ENOMEM;
1394 		binder_proc_lock(proc);
1395 		ref = binder_get_ref_for_node_olocked(proc, node, new_ref);
1396 	}
1397 	ret = binder_inc_ref_olocked(ref, strong, target_list);
1398 	*rdata = ref->data;
1399 	if (ret && ref == new_ref) {
1400 		/*
1401 		 * Cleanup the failed reference here as the target
1402 		 * could now be dead and have already released its
1403 		 * references by now. Calling on the new reference
1404 		 * with strong=0 and a tmp_refs will not decrement
1405 		 * the node. The new_ref gets kfree'd below.
1406 		 */
1407 		binder_cleanup_ref_olocked(new_ref);
1408 		ref = NULL;
1409 	}
1410 
1411 	binder_proc_unlock(proc);
1412 	if (new_ref && ref != new_ref)
1413 		/*
1414 		 * Another thread created the ref first so
1415 		 * free the one we allocated
1416 		 */
1417 		kfree(new_ref);
1418 	return ret;
1419 }
1420 
binder_pop_transaction_ilocked(struct binder_thread * target_thread,struct binder_transaction * t)1421 static void binder_pop_transaction_ilocked(struct binder_thread *target_thread,
1422 					   struct binder_transaction *t)
1423 {
1424 	BUG_ON(!target_thread);
1425 	assert_spin_locked(&target_thread->proc->inner_lock);
1426 	BUG_ON(target_thread->transaction_stack != t);
1427 	BUG_ON(target_thread->transaction_stack->from != target_thread);
1428 	target_thread->transaction_stack =
1429 		target_thread->transaction_stack->from_parent;
1430 	t->from = NULL;
1431 }
1432 
1433 /**
1434  * binder_thread_dec_tmpref() - decrement thread->tmp_ref
1435  * @thread:	thread to decrement
1436  *
1437  * A thread needs to be kept alive while being used to create or
1438  * handle a transaction. binder_get_txn_from() is used to safely
1439  * extract t->from from a binder_transaction and keep the thread
1440  * indicated by t->from from being freed. When done with that
1441  * binder_thread, this function is called to decrement the
1442  * tmp_ref and free if appropriate (thread has been released
1443  * and no transaction being processed by the driver)
1444  */
binder_thread_dec_tmpref(struct binder_thread * thread)1445 static void binder_thread_dec_tmpref(struct binder_thread *thread)
1446 {
1447 	/*
1448 	 * atomic is used to protect the counter value while
1449 	 * it cannot reach zero or thread->is_dead is false
1450 	 */
1451 	binder_inner_proc_lock(thread->proc);
1452 	atomic_dec(&thread->tmp_ref);
1453 	if (thread->is_dead && !atomic_read(&thread->tmp_ref)) {
1454 		binder_inner_proc_unlock(thread->proc);
1455 		binder_free_thread(thread);
1456 		return;
1457 	}
1458 	binder_inner_proc_unlock(thread->proc);
1459 }
1460 
1461 /**
1462  * binder_proc_dec_tmpref() - decrement proc->tmp_ref
1463  * @proc:	proc to decrement
1464  *
1465  * A binder_proc needs to be kept alive while being used to create or
1466  * handle a transaction. proc->tmp_ref is incremented when
1467  * creating a new transaction or the binder_proc is currently in-use
1468  * by threads that are being released. When done with the binder_proc,
1469  * this function is called to decrement the counter and free the
1470  * proc if appropriate (proc has been released, all threads have
1471  * been released and not currenly in-use to process a transaction).
1472  */
binder_proc_dec_tmpref(struct binder_proc * proc)1473 static void binder_proc_dec_tmpref(struct binder_proc *proc)
1474 {
1475 	binder_inner_proc_lock(proc);
1476 	proc->tmp_ref--;
1477 	if (proc->is_dead && RB_EMPTY_ROOT(&proc->threads) &&
1478 			!proc->tmp_ref) {
1479 		binder_inner_proc_unlock(proc);
1480 		binder_free_proc(proc);
1481 		return;
1482 	}
1483 	binder_inner_proc_unlock(proc);
1484 }
1485 
1486 /**
1487  * binder_get_txn_from() - safely extract the "from" thread in transaction
1488  * @t:	binder transaction for t->from
1489  *
1490  * Atomically return the "from" thread and increment the tmp_ref
1491  * count for the thread to ensure it stays alive until
1492  * binder_thread_dec_tmpref() is called.
1493  *
1494  * Return: the value of t->from
1495  */
binder_get_txn_from(struct binder_transaction * t)1496 static struct binder_thread *binder_get_txn_from(
1497 		struct binder_transaction *t)
1498 {
1499 	struct binder_thread *from;
1500 
1501 	spin_lock(&t->lock);
1502 	from = t->from;
1503 	if (from)
1504 		atomic_inc(&from->tmp_ref);
1505 	spin_unlock(&t->lock);
1506 	return from;
1507 }
1508 
1509 /**
1510  * binder_get_txn_from_and_acq_inner() - get t->from and acquire inner lock
1511  * @t:	binder transaction for t->from
1512  *
1513  * Same as binder_get_txn_from() except it also acquires the proc->inner_lock
1514  * to guarantee that the thread cannot be released while operating on it.
1515  * The caller must call binder_inner_proc_unlock() to release the inner lock
1516  * as well as call binder_dec_thread_txn() to release the reference.
1517  *
1518  * Return: the value of t->from
1519  */
binder_get_txn_from_and_acq_inner(struct binder_transaction * t)1520 static struct binder_thread *binder_get_txn_from_and_acq_inner(
1521 		struct binder_transaction *t)
1522 	__acquires(&t->from->proc->inner_lock)
1523 {
1524 	struct binder_thread *from;
1525 
1526 	from = binder_get_txn_from(t);
1527 	if (!from) {
1528 		__acquire(&from->proc->inner_lock);
1529 		return NULL;
1530 	}
1531 	binder_inner_proc_lock(from->proc);
1532 	if (t->from) {
1533 		BUG_ON(from != t->from);
1534 		return from;
1535 	}
1536 	binder_inner_proc_unlock(from->proc);
1537 	__acquire(&from->proc->inner_lock);
1538 	binder_thread_dec_tmpref(from);
1539 	return NULL;
1540 }
1541 
1542 /**
1543  * binder_free_txn_fixups() - free unprocessed fd fixups
1544  * @t:	binder transaction for t->from
1545  *
1546  * If the transaction is being torn down prior to being
1547  * processed by the target process, free all of the
1548  * fd fixups and fput the file structs. It is safe to
1549  * call this function after the fixups have been
1550  * processed -- in that case, the list will be empty.
1551  */
binder_free_txn_fixups(struct binder_transaction * t)1552 static void binder_free_txn_fixups(struct binder_transaction *t)
1553 {
1554 	struct binder_txn_fd_fixup *fixup, *tmp;
1555 
1556 	list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
1557 		fput(fixup->file);
1558 		if (fixup->target_fd >= 0)
1559 			put_unused_fd(fixup->target_fd);
1560 		list_del(&fixup->fixup_entry);
1561 		kfree(fixup);
1562 	}
1563 }
1564 
binder_txn_latency_free(struct binder_transaction * t)1565 static void binder_txn_latency_free(struct binder_transaction *t)
1566 {
1567 	int from_proc, from_thread, to_proc, to_thread;
1568 
1569 	spin_lock(&t->lock);
1570 	from_proc = t->from ? t->from->proc->pid : 0;
1571 	from_thread = t->from ? t->from->pid : 0;
1572 	to_proc = t->to_proc ? t->to_proc->pid : 0;
1573 	to_thread = t->to_thread ? t->to_thread->pid : 0;
1574 	spin_unlock(&t->lock);
1575 
1576 	trace_binder_txn_latency_free(t, from_proc, from_thread, to_proc, to_thread);
1577 }
1578 
binder_free_transaction(struct binder_transaction * t)1579 static void binder_free_transaction(struct binder_transaction *t)
1580 {
1581 	struct binder_proc *target_proc = t->to_proc;
1582 
1583 	if (target_proc) {
1584 		binder_inner_proc_lock(target_proc);
1585 		target_proc->outstanding_txns--;
1586 		if (target_proc->outstanding_txns < 0)
1587 			pr_warn("%s: Unexpected outstanding_txns %d\n",
1588 				__func__, target_proc->outstanding_txns);
1589 		if (!target_proc->outstanding_txns && target_proc->is_frozen)
1590 			wake_up_interruptible_all(&target_proc->freeze_wait);
1591 		if (t->buffer)
1592 			t->buffer->transaction = NULL;
1593 		binder_inner_proc_unlock(target_proc);
1594 	}
1595 	if (trace_binder_txn_latency_free_enabled())
1596 		binder_txn_latency_free(t);
1597 	/*
1598 	 * If the transaction has no target_proc, then
1599 	 * t->buffer->transaction has already been cleared.
1600 	 */
1601 	binder_free_txn_fixups(t);
1602 	kfree(t);
1603 	binder_stats_deleted(BINDER_STAT_TRANSACTION);
1604 }
1605 
binder_send_failed_reply(struct binder_transaction * t,uint32_t error_code)1606 static void binder_send_failed_reply(struct binder_transaction *t,
1607 				     uint32_t error_code)
1608 {
1609 	struct binder_thread *target_thread;
1610 	struct binder_transaction *next;
1611 
1612 	BUG_ON(t->flags & TF_ONE_WAY);
1613 	while (1) {
1614 		target_thread = binder_get_txn_from_and_acq_inner(t);
1615 		if (target_thread) {
1616 			binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
1617 				     "send failed reply for transaction %d to %d:%d\n",
1618 				      t->debug_id,
1619 				      target_thread->proc->pid,
1620 				      target_thread->pid);
1621 
1622 			binder_pop_transaction_ilocked(target_thread, t);
1623 			if (target_thread->reply_error.cmd == BR_OK) {
1624 				target_thread->reply_error.cmd = error_code;
1625 				binder_enqueue_thread_work_ilocked(
1626 					target_thread,
1627 					&target_thread->reply_error.work);
1628 				wake_up_interruptible(&target_thread->wait);
1629 			} else {
1630 				/*
1631 				 * Cannot get here for normal operation, but
1632 				 * we can if multiple synchronous transactions
1633 				 * are sent without blocking for responses.
1634 				 * Just ignore the 2nd error in this case.
1635 				 */
1636 				pr_warn("Unexpected reply error: %u\n",
1637 					target_thread->reply_error.cmd);
1638 			}
1639 			binder_inner_proc_unlock(target_thread->proc);
1640 			binder_thread_dec_tmpref(target_thread);
1641 			binder_free_transaction(t);
1642 			return;
1643 		}
1644 		__release(&target_thread->proc->inner_lock);
1645 		next = t->from_parent;
1646 
1647 		binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
1648 			     "send failed reply for transaction %d, target dead\n",
1649 			     t->debug_id);
1650 
1651 		binder_free_transaction(t);
1652 		if (next == NULL) {
1653 			binder_debug(BINDER_DEBUG_DEAD_BINDER,
1654 				     "reply failed, no target thread at root\n");
1655 			return;
1656 		}
1657 		t = next;
1658 		binder_debug(BINDER_DEBUG_DEAD_BINDER,
1659 			     "reply failed, no target thread -- retry %d\n",
1660 			      t->debug_id);
1661 	}
1662 }
1663 
1664 /**
1665  * binder_cleanup_transaction() - cleans up undelivered transaction
1666  * @t:		transaction that needs to be cleaned up
1667  * @reason:	reason the transaction wasn't delivered
1668  * @error_code:	error to return to caller (if synchronous call)
1669  */
binder_cleanup_transaction(struct binder_transaction * t,const char * reason,uint32_t error_code)1670 static void binder_cleanup_transaction(struct binder_transaction *t,
1671 				       const char *reason,
1672 				       uint32_t error_code)
1673 {
1674 	if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) {
1675 		binder_send_failed_reply(t, error_code);
1676 	} else {
1677 		binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
1678 			"undelivered transaction %d, %s\n",
1679 			t->debug_id, reason);
1680 		binder_free_transaction(t);
1681 	}
1682 }
1683 
1684 /**
1685  * binder_get_object() - gets object and checks for valid metadata
1686  * @proc:	binder_proc owning the buffer
1687  * @u:		sender's user pointer to base of buffer
1688  * @buffer:	binder_buffer that we're parsing.
1689  * @offset:	offset in the @buffer at which to validate an object.
1690  * @object:	struct binder_object to read into
1691  *
1692  * Copy the binder object at the given offset into @object. If @u is
1693  * provided then the copy is from the sender's buffer. If not, then
1694  * it is copied from the target's @buffer.
1695  *
1696  * Return:	If there's a valid metadata object at @offset, the
1697  *		size of that object. Otherwise, it returns zero. The object
1698  *		is read into the struct binder_object pointed to by @object.
1699  */
binder_get_object(struct binder_proc * proc,const void __user * u,struct binder_buffer * buffer,unsigned long offset,struct binder_object * object)1700 static size_t binder_get_object(struct binder_proc *proc,
1701 				const void __user *u,
1702 				struct binder_buffer *buffer,
1703 				unsigned long offset,
1704 				struct binder_object *object)
1705 {
1706 	size_t read_size;
1707 	struct binder_object_header *hdr;
1708 	size_t object_size = 0;
1709 
1710 	read_size = min_t(size_t, sizeof(*object), buffer->data_size - offset);
1711 	if (offset > buffer->data_size || read_size < sizeof(*hdr) ||
1712 	    !IS_ALIGNED(offset, sizeof(u32)))
1713 		return 0;
1714 
1715 	if (u) {
1716 		if (copy_from_user(object, u + offset, read_size))
1717 			return 0;
1718 	} else {
1719 		if (binder_alloc_copy_from_buffer(&proc->alloc, object, buffer,
1720 						  offset, read_size))
1721 			return 0;
1722 	}
1723 
1724 	/* Ok, now see if we read a complete object. */
1725 	hdr = &object->hdr;
1726 	switch (hdr->type) {
1727 	case BINDER_TYPE_BINDER:
1728 	case BINDER_TYPE_WEAK_BINDER:
1729 	case BINDER_TYPE_HANDLE:
1730 	case BINDER_TYPE_WEAK_HANDLE:
1731 		object_size = sizeof(struct flat_binder_object);
1732 		break;
1733 	case BINDER_TYPE_FD:
1734 		object_size = sizeof(struct binder_fd_object);
1735 		break;
1736 	case BINDER_TYPE_PTR:
1737 		object_size = sizeof(struct binder_buffer_object);
1738 		break;
1739 	case BINDER_TYPE_FDA:
1740 		object_size = sizeof(struct binder_fd_array_object);
1741 		break;
1742 	default:
1743 		return 0;
1744 	}
1745 	if (offset <= buffer->data_size - object_size &&
1746 	    buffer->data_size >= object_size)
1747 		return object_size;
1748 	else
1749 		return 0;
1750 }
1751 
1752 /**
1753  * binder_validate_ptr() - validates binder_buffer_object in a binder_buffer.
1754  * @proc:	binder_proc owning the buffer
1755  * @b:		binder_buffer containing the object
1756  * @object:	struct binder_object to read into
1757  * @index:	index in offset array at which the binder_buffer_object is
1758  *		located
1759  * @start_offset: points to the start of the offset array
1760  * @object_offsetp: offset of @object read from @b
1761  * @num_valid:	the number of valid offsets in the offset array
1762  *
1763  * Return:	If @index is within the valid range of the offset array
1764  *		described by @start and @num_valid, and if there's a valid
1765  *		binder_buffer_object at the offset found in index @index
1766  *		of the offset array, that object is returned. Otherwise,
1767  *		%NULL is returned.
1768  *		Note that the offset found in index @index itself is not
1769  *		verified; this function assumes that @num_valid elements
1770  *		from @start were previously verified to have valid offsets.
1771  *		If @object_offsetp is non-NULL, then the offset within
1772  *		@b is written to it.
1773  */
binder_validate_ptr(struct binder_proc * proc,struct binder_buffer * b,struct binder_object * object,binder_size_t index,binder_size_t start_offset,binder_size_t * object_offsetp,binder_size_t num_valid)1774 static struct binder_buffer_object *binder_validate_ptr(
1775 						struct binder_proc *proc,
1776 						struct binder_buffer *b,
1777 						struct binder_object *object,
1778 						binder_size_t index,
1779 						binder_size_t start_offset,
1780 						binder_size_t *object_offsetp,
1781 						binder_size_t num_valid)
1782 {
1783 	size_t object_size;
1784 	binder_size_t object_offset;
1785 	unsigned long buffer_offset;
1786 
1787 	if (index >= num_valid)
1788 		return NULL;
1789 
1790 	buffer_offset = start_offset + sizeof(binder_size_t) * index;
1791 	if (binder_alloc_copy_from_buffer(&proc->alloc, &object_offset,
1792 					  b, buffer_offset,
1793 					  sizeof(object_offset)))
1794 		return NULL;
1795 	object_size = binder_get_object(proc, NULL, b, object_offset, object);
1796 	if (!object_size || object->hdr.type != BINDER_TYPE_PTR)
1797 		return NULL;
1798 	if (object_offsetp)
1799 		*object_offsetp = object_offset;
1800 
1801 	return &object->bbo;
1802 }
1803 
1804 /**
1805  * binder_validate_fixup() - validates pointer/fd fixups happen in order.
1806  * @proc:		binder_proc owning the buffer
1807  * @b:			transaction buffer
1808  * @objects_start_offset: offset to start of objects buffer
1809  * @buffer_obj_offset:	offset to binder_buffer_object in which to fix up
1810  * @fixup_offset:	start offset in @buffer to fix up
1811  * @last_obj_offset:	offset to last binder_buffer_object that we fixed
1812  * @last_min_offset:	minimum fixup offset in object at @last_obj_offset
1813  *
1814  * Return:		%true if a fixup in buffer @buffer at offset @offset is
1815  *			allowed.
1816  *
1817  * For safety reasons, we only allow fixups inside a buffer to happen
1818  * at increasing offsets; additionally, we only allow fixup on the last
1819  * buffer object that was verified, or one of its parents.
1820  *
1821  * Example of what is allowed:
1822  *
1823  * A
1824  *   B (parent = A, offset = 0)
1825  *   C (parent = A, offset = 16)
1826  *     D (parent = C, offset = 0)
1827  *   E (parent = A, offset = 32) // min_offset is 16 (C.parent_offset)
1828  *
1829  * Examples of what is not allowed:
1830  *
1831  * Decreasing offsets within the same parent:
1832  * A
1833  *   C (parent = A, offset = 16)
1834  *   B (parent = A, offset = 0) // decreasing offset within A
1835  *
1836  * Referring to a parent that wasn't the last object or any of its parents:
1837  * A
1838  *   B (parent = A, offset = 0)
1839  *   C (parent = A, offset = 0)
1840  *   C (parent = A, offset = 16)
1841  *     D (parent = B, offset = 0) // B is not A or any of A's parents
1842  */
binder_validate_fixup(struct binder_proc * proc,struct binder_buffer * b,binder_size_t objects_start_offset,binder_size_t buffer_obj_offset,binder_size_t fixup_offset,binder_size_t last_obj_offset,binder_size_t last_min_offset)1843 static bool binder_validate_fixup(struct binder_proc *proc,
1844 				  struct binder_buffer *b,
1845 				  binder_size_t objects_start_offset,
1846 				  binder_size_t buffer_obj_offset,
1847 				  binder_size_t fixup_offset,
1848 				  binder_size_t last_obj_offset,
1849 				  binder_size_t last_min_offset)
1850 {
1851 	if (!last_obj_offset) {
1852 		/* Nothing to fix up in */
1853 		return false;
1854 	}
1855 
1856 	while (last_obj_offset != buffer_obj_offset) {
1857 		unsigned long buffer_offset;
1858 		struct binder_object last_object;
1859 		struct binder_buffer_object *last_bbo;
1860 		size_t object_size = binder_get_object(proc, NULL, b,
1861 						       last_obj_offset,
1862 						       &last_object);
1863 		if (object_size != sizeof(*last_bbo))
1864 			return false;
1865 
1866 		last_bbo = &last_object.bbo;
1867 		/*
1868 		 * Safe to retrieve the parent of last_obj, since it
1869 		 * was already previously verified by the driver.
1870 		 */
1871 		if ((last_bbo->flags & BINDER_BUFFER_FLAG_HAS_PARENT) == 0)
1872 			return false;
1873 		last_min_offset = last_bbo->parent_offset + sizeof(uintptr_t);
1874 		buffer_offset = objects_start_offset +
1875 			sizeof(binder_size_t) * last_bbo->parent;
1876 		if (binder_alloc_copy_from_buffer(&proc->alloc,
1877 						  &last_obj_offset,
1878 						  b, buffer_offset,
1879 						  sizeof(last_obj_offset)))
1880 			return false;
1881 	}
1882 	return (fixup_offset >= last_min_offset);
1883 }
1884 
1885 /**
1886  * struct binder_task_work_cb - for deferred close
1887  *
1888  * @twork:                callback_head for task work
1889  * @fd:                   fd to close
1890  *
1891  * Structure to pass task work to be handled after
1892  * returning from binder_ioctl() via task_work_add().
1893  */
1894 struct binder_task_work_cb {
1895 	struct callback_head twork;
1896 	struct file *file;
1897 };
1898 
1899 /**
1900  * binder_do_fd_close() - close list of file descriptors
1901  * @twork:	callback head for task work
1902  *
1903  * It is not safe to call ksys_close() during the binder_ioctl()
1904  * function if there is a chance that binder's own file descriptor
1905  * might be closed. This is to meet the requirements for using
1906  * fdget() (see comments for __fget_light()). Therefore use
1907  * task_work_add() to schedule the close operation once we have
1908  * returned from binder_ioctl(). This function is a callback
1909  * for that mechanism and does the actual ksys_close() on the
1910  * given file descriptor.
1911  */
binder_do_fd_close(struct callback_head * twork)1912 static void binder_do_fd_close(struct callback_head *twork)
1913 {
1914 	struct binder_task_work_cb *twcb = container_of(twork,
1915 			struct binder_task_work_cb, twork);
1916 
1917 	fput(twcb->file);
1918 	kfree(twcb);
1919 }
1920 
1921 /**
1922  * binder_deferred_fd_close() - schedule a close for the given file-descriptor
1923  * @fd:		file-descriptor to close
1924  *
1925  * See comments in binder_do_fd_close(). This function is used to schedule
1926  * a file-descriptor to be closed after returning from binder_ioctl().
1927  */
binder_deferred_fd_close(int fd)1928 static void binder_deferred_fd_close(int fd)
1929 {
1930 	struct binder_task_work_cb *twcb;
1931 
1932 	twcb = kzalloc(sizeof(*twcb), GFP_KERNEL);
1933 	if (!twcb)
1934 		return;
1935 	init_task_work(&twcb->twork, binder_do_fd_close);
1936 	twcb->file = close_fd_get_file(fd);
1937 	if (twcb->file) {
1938 		// pin it until binder_do_fd_close(); see comments there
1939 		get_file(twcb->file);
1940 		filp_close(twcb->file, current->files);
1941 		task_work_add(current, &twcb->twork, TWA_RESUME);
1942 	} else {
1943 		kfree(twcb);
1944 	}
1945 }
1946 
binder_transaction_buffer_release(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,binder_size_t off_end_offset,bool is_failure)1947 static void binder_transaction_buffer_release(struct binder_proc *proc,
1948 					      struct binder_thread *thread,
1949 					      struct binder_buffer *buffer,
1950 					      binder_size_t off_end_offset,
1951 					      bool is_failure)
1952 {
1953 	int debug_id = buffer->debug_id;
1954 	binder_size_t off_start_offset, buffer_offset;
1955 
1956 	binder_debug(BINDER_DEBUG_TRANSACTION,
1957 		     "%d buffer release %d, size %zd-%zd, failed at %llx\n",
1958 		     proc->pid, buffer->debug_id,
1959 		     buffer->data_size, buffer->offsets_size,
1960 		     (unsigned long long)off_end_offset);
1961 
1962 	if (buffer->target_node)
1963 		binder_dec_node(buffer->target_node, 1, 0);
1964 
1965 	off_start_offset = ALIGN(buffer->data_size, sizeof(void *));
1966 
1967 	for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
1968 	     buffer_offset += sizeof(binder_size_t)) {
1969 		struct binder_object_header *hdr;
1970 		size_t object_size = 0;
1971 		struct binder_object object;
1972 		binder_size_t object_offset;
1973 
1974 		if (!binder_alloc_copy_from_buffer(&proc->alloc, &object_offset,
1975 						   buffer, buffer_offset,
1976 						   sizeof(object_offset)))
1977 			object_size = binder_get_object(proc, NULL, buffer,
1978 							object_offset, &object);
1979 		if (object_size == 0) {
1980 			pr_err("transaction release %d bad object at offset %lld, size %zd\n",
1981 			       debug_id, (u64)object_offset, buffer->data_size);
1982 			continue;
1983 		}
1984 		hdr = &object.hdr;
1985 		switch (hdr->type) {
1986 		case BINDER_TYPE_BINDER:
1987 		case BINDER_TYPE_WEAK_BINDER: {
1988 			struct flat_binder_object *fp;
1989 			struct binder_node *node;
1990 
1991 			fp = to_flat_binder_object(hdr);
1992 			node = binder_get_node(proc, fp->binder);
1993 			if (node == NULL) {
1994 				pr_err("transaction release %d bad node %016llx\n",
1995 				       debug_id, (u64)fp->binder);
1996 				break;
1997 			}
1998 			binder_debug(BINDER_DEBUG_TRANSACTION,
1999 				     "        node %d u%016llx\n",
2000 				     node->debug_id, (u64)node->ptr);
2001 			binder_dec_node(node, hdr->type == BINDER_TYPE_BINDER,
2002 					0);
2003 			binder_put_node(node);
2004 		} break;
2005 		case BINDER_TYPE_HANDLE:
2006 		case BINDER_TYPE_WEAK_HANDLE: {
2007 			struct flat_binder_object *fp;
2008 			struct binder_ref_data rdata;
2009 			int ret;
2010 
2011 			fp = to_flat_binder_object(hdr);
2012 			ret = binder_dec_ref_for_handle(proc, fp->handle,
2013 				hdr->type == BINDER_TYPE_HANDLE, &rdata);
2014 
2015 			if (ret) {
2016 				pr_err("transaction release %d bad handle %d, ret = %d\n",
2017 				 debug_id, fp->handle, ret);
2018 				break;
2019 			}
2020 			binder_debug(BINDER_DEBUG_TRANSACTION,
2021 				     "        ref %d desc %d\n",
2022 				     rdata.debug_id, rdata.desc);
2023 		} break;
2024 
2025 		case BINDER_TYPE_FD: {
2026 			/*
2027 			 * No need to close the file here since user-space
2028 			 * closes it for successfully delivered
2029 			 * transactions. For transactions that weren't
2030 			 * delivered, the new fd was never allocated so
2031 			 * there is no need to close and the fput on the
2032 			 * file is done when the transaction is torn
2033 			 * down.
2034 			 */
2035 		} break;
2036 		case BINDER_TYPE_PTR:
2037 			/*
2038 			 * Nothing to do here, this will get cleaned up when the
2039 			 * transaction buffer gets freed
2040 			 */
2041 			break;
2042 		case BINDER_TYPE_FDA: {
2043 			struct binder_fd_array_object *fda;
2044 			struct binder_buffer_object *parent;
2045 			struct binder_object ptr_object;
2046 			binder_size_t fda_offset;
2047 			size_t fd_index;
2048 			binder_size_t fd_buf_size;
2049 			binder_size_t num_valid;
2050 
2051 			if (is_failure) {
2052 				/*
2053 				 * The fd fixups have not been applied so no
2054 				 * fds need to be closed.
2055 				 */
2056 				continue;
2057 			}
2058 
2059 			num_valid = (buffer_offset - off_start_offset) /
2060 						sizeof(binder_size_t);
2061 			fda = to_binder_fd_array_object(hdr);
2062 			parent = binder_validate_ptr(proc, buffer, &ptr_object,
2063 						     fda->parent,
2064 						     off_start_offset,
2065 						     NULL,
2066 						     num_valid);
2067 			if (!parent) {
2068 				pr_err("transaction release %d bad parent offset\n",
2069 				       debug_id);
2070 				continue;
2071 			}
2072 			fd_buf_size = sizeof(u32) * fda->num_fds;
2073 			if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
2074 				pr_err("transaction release %d invalid number of fds (%lld)\n",
2075 				       debug_id, (u64)fda->num_fds);
2076 				continue;
2077 			}
2078 			if (fd_buf_size > parent->length ||
2079 			    fda->parent_offset > parent->length - fd_buf_size) {
2080 				/* No space for all file descriptors here. */
2081 				pr_err("transaction release %d not enough space for %lld fds in buffer\n",
2082 				       debug_id, (u64)fda->num_fds);
2083 				continue;
2084 			}
2085 			/*
2086 			 * the source data for binder_buffer_object is visible
2087 			 * to user-space and the @buffer element is the user
2088 			 * pointer to the buffer_object containing the fd_array.
2089 			 * Convert the address to an offset relative to
2090 			 * the base of the transaction buffer.
2091 			 */
2092 			fda_offset =
2093 			    (parent->buffer - (uintptr_t)buffer->user_data) +
2094 			    fda->parent_offset;
2095 			for (fd_index = 0; fd_index < fda->num_fds;
2096 			     fd_index++) {
2097 				u32 fd;
2098 				int err;
2099 				binder_size_t offset = fda_offset +
2100 					fd_index * sizeof(fd);
2101 
2102 				err = binder_alloc_copy_from_buffer(
2103 						&proc->alloc, &fd, buffer,
2104 						offset, sizeof(fd));
2105 				WARN_ON(err);
2106 				if (!err) {
2107 					binder_deferred_fd_close(fd);
2108 					/*
2109 					 * Need to make sure the thread goes
2110 					 * back to userspace to complete the
2111 					 * deferred close
2112 					 */
2113 					if (thread)
2114 						thread->looper_need_return = true;
2115 				}
2116 			}
2117 		} break;
2118 		default:
2119 			pr_err("transaction release %d bad object type %x\n",
2120 				debug_id, hdr->type);
2121 			break;
2122 		}
2123 	}
2124 }
2125 
2126 /* Clean up all the objects in the buffer */
binder_release_entire_buffer(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,bool is_failure)2127 static inline void binder_release_entire_buffer(struct binder_proc *proc,
2128 						struct binder_thread *thread,
2129 						struct binder_buffer *buffer,
2130 						bool is_failure)
2131 {
2132 	binder_size_t off_end_offset;
2133 
2134 	off_end_offset = ALIGN(buffer->data_size, sizeof(void *));
2135 	off_end_offset += buffer->offsets_size;
2136 
2137 	binder_transaction_buffer_release(proc, thread, buffer,
2138 					  off_end_offset, is_failure);
2139 }
2140 
binder_translate_binder(struct flat_binder_object * fp,struct binder_transaction * t,struct binder_thread * thread)2141 static int binder_translate_binder(struct flat_binder_object *fp,
2142 				   struct binder_transaction *t,
2143 				   struct binder_thread *thread)
2144 {
2145 	struct binder_node *node;
2146 	struct binder_proc *proc = thread->proc;
2147 	struct binder_proc *target_proc = t->to_proc;
2148 	struct binder_ref_data rdata;
2149 	int ret = 0;
2150 
2151 	node = binder_get_node(proc, fp->binder);
2152 	if (!node) {
2153 		node = binder_new_node(proc, fp);
2154 		if (!node)
2155 			return -ENOMEM;
2156 	}
2157 	if (fp->cookie != node->cookie) {
2158 		binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n",
2159 				  proc->pid, thread->pid, (u64)fp->binder,
2160 				  node->debug_id, (u64)fp->cookie,
2161 				  (u64)node->cookie);
2162 		ret = -EINVAL;
2163 		goto done;
2164 	}
2165 	if (security_binder_transfer_binder(proc->cred, target_proc->cred)) {
2166 		ret = -EPERM;
2167 		goto done;
2168 	}
2169 
2170 	ret = binder_inc_ref_for_node(target_proc, node,
2171 			fp->hdr.type == BINDER_TYPE_BINDER,
2172 			&thread->todo, &rdata);
2173 	if (ret)
2174 		goto done;
2175 
2176 	if (fp->hdr.type == BINDER_TYPE_BINDER)
2177 		fp->hdr.type = BINDER_TYPE_HANDLE;
2178 	else
2179 		fp->hdr.type = BINDER_TYPE_WEAK_HANDLE;
2180 	fp->binder = 0;
2181 	fp->handle = rdata.desc;
2182 	fp->cookie = 0;
2183 
2184 	trace_binder_transaction_node_to_ref(t, node, &rdata);
2185 	binder_debug(BINDER_DEBUG_TRANSACTION,
2186 		     "        node %d u%016llx -> ref %d desc %d\n",
2187 		     node->debug_id, (u64)node->ptr,
2188 		     rdata.debug_id, rdata.desc);
2189 done:
2190 	binder_put_node(node);
2191 	return ret;
2192 }
2193 
binder_translate_handle(struct flat_binder_object * fp,struct binder_transaction * t,struct binder_thread * thread)2194 static int binder_translate_handle(struct flat_binder_object *fp,
2195 				   struct binder_transaction *t,
2196 				   struct binder_thread *thread)
2197 {
2198 	struct binder_proc *proc = thread->proc;
2199 	struct binder_proc *target_proc = t->to_proc;
2200 	struct binder_node *node;
2201 	struct binder_ref_data src_rdata;
2202 	int ret = 0;
2203 
2204 	node = binder_get_node_from_ref(proc, fp->handle,
2205 			fp->hdr.type == BINDER_TYPE_HANDLE, &src_rdata);
2206 	if (!node) {
2207 		binder_user_error("%d:%d got transaction with invalid handle, %d\n",
2208 				  proc->pid, thread->pid, fp->handle);
2209 		return -EINVAL;
2210 	}
2211 	if (security_binder_transfer_binder(proc->cred, target_proc->cred)) {
2212 		ret = -EPERM;
2213 		goto done;
2214 	}
2215 
2216 	binder_node_lock(node);
2217 	if (node->proc == target_proc) {
2218 		if (fp->hdr.type == BINDER_TYPE_HANDLE)
2219 			fp->hdr.type = BINDER_TYPE_BINDER;
2220 		else
2221 			fp->hdr.type = BINDER_TYPE_WEAK_BINDER;
2222 		fp->binder = node->ptr;
2223 		fp->cookie = node->cookie;
2224 		if (node->proc)
2225 			binder_inner_proc_lock(node->proc);
2226 		else
2227 			__acquire(&node->proc->inner_lock);
2228 		binder_inc_node_nilocked(node,
2229 					 fp->hdr.type == BINDER_TYPE_BINDER,
2230 					 0, NULL);
2231 		if (node->proc)
2232 			binder_inner_proc_unlock(node->proc);
2233 		else
2234 			__release(&node->proc->inner_lock);
2235 		trace_binder_transaction_ref_to_node(t, node, &src_rdata);
2236 		binder_debug(BINDER_DEBUG_TRANSACTION,
2237 			     "        ref %d desc %d -> node %d u%016llx\n",
2238 			     src_rdata.debug_id, src_rdata.desc, node->debug_id,
2239 			     (u64)node->ptr);
2240 		binder_node_unlock(node);
2241 	} else {
2242 		struct binder_ref_data dest_rdata;
2243 
2244 		binder_node_unlock(node);
2245 		ret = binder_inc_ref_for_node(target_proc, node,
2246 				fp->hdr.type == BINDER_TYPE_HANDLE,
2247 				NULL, &dest_rdata);
2248 		if (ret)
2249 			goto done;
2250 
2251 		fp->binder = 0;
2252 		fp->handle = dest_rdata.desc;
2253 		fp->cookie = 0;
2254 		trace_binder_transaction_ref_to_ref(t, node, &src_rdata,
2255 						    &dest_rdata);
2256 		binder_debug(BINDER_DEBUG_TRANSACTION,
2257 			     "        ref %d desc %d -> ref %d desc %d (node %d)\n",
2258 			     src_rdata.debug_id, src_rdata.desc,
2259 			     dest_rdata.debug_id, dest_rdata.desc,
2260 			     node->debug_id);
2261 	}
2262 done:
2263 	binder_put_node(node);
2264 	return ret;
2265 }
2266 
binder_translate_fd(u32 fd,binder_size_t fd_offset,struct binder_transaction * t,struct binder_thread * thread,struct binder_transaction * in_reply_to)2267 static int binder_translate_fd(u32 fd, binder_size_t fd_offset,
2268 			       struct binder_transaction *t,
2269 			       struct binder_thread *thread,
2270 			       struct binder_transaction *in_reply_to)
2271 {
2272 	struct binder_proc *proc = thread->proc;
2273 	struct binder_proc *target_proc = t->to_proc;
2274 	struct binder_txn_fd_fixup *fixup;
2275 	struct file *file;
2276 	int ret = 0;
2277 	bool target_allows_fd;
2278 
2279 	if (in_reply_to)
2280 		target_allows_fd = !!(in_reply_to->flags & TF_ACCEPT_FDS);
2281 	else
2282 		target_allows_fd = t->buffer->target_node->accept_fds;
2283 	if (!target_allows_fd) {
2284 		binder_user_error("%d:%d got %s with fd, %d, but target does not allow fds\n",
2285 				  proc->pid, thread->pid,
2286 				  in_reply_to ? "reply" : "transaction",
2287 				  fd);
2288 		ret = -EPERM;
2289 		goto err_fd_not_accepted;
2290 	}
2291 
2292 	file = fget(fd);
2293 	if (!file) {
2294 		binder_user_error("%d:%d got transaction with invalid fd, %d\n",
2295 				  proc->pid, thread->pid, fd);
2296 		ret = -EBADF;
2297 		goto err_fget;
2298 	}
2299 	ret = security_binder_transfer_file(proc->cred, target_proc->cred, file);
2300 	if (ret < 0) {
2301 		ret = -EPERM;
2302 		goto err_security;
2303 	}
2304 
2305 	/*
2306 	 * Add fixup record for this transaction. The allocation
2307 	 * of the fd in the target needs to be done from a
2308 	 * target thread.
2309 	 */
2310 	fixup = kzalloc(sizeof(*fixup), GFP_KERNEL);
2311 	if (!fixup) {
2312 		ret = -ENOMEM;
2313 		goto err_alloc;
2314 	}
2315 	fixup->file = file;
2316 	fixup->offset = fd_offset;
2317 	fixup->target_fd = -1;
2318 	trace_binder_transaction_fd_send(t, fd, fixup->offset);
2319 	list_add_tail(&fixup->fixup_entry, &t->fd_fixups);
2320 
2321 	return ret;
2322 
2323 err_alloc:
2324 err_security:
2325 	fput(file);
2326 err_fget:
2327 err_fd_not_accepted:
2328 	return ret;
2329 }
2330 
2331 /**
2332  * struct binder_ptr_fixup - data to be fixed-up in target buffer
2333  * @offset	offset in target buffer to fixup
2334  * @skip_size	bytes to skip in copy (fixup will be written later)
2335  * @fixup_data	data to write at fixup offset
2336  * @node	list node
2337  *
2338  * This is used for the pointer fixup list (pf) which is created and consumed
2339  * during binder_transaction() and is only accessed locally. No
2340  * locking is necessary.
2341  *
2342  * The list is ordered by @offset.
2343  */
2344 struct binder_ptr_fixup {
2345 	binder_size_t offset;
2346 	size_t skip_size;
2347 	binder_uintptr_t fixup_data;
2348 	struct list_head node;
2349 };
2350 
2351 /**
2352  * struct binder_sg_copy - scatter-gather data to be copied
2353  * @offset		offset in target buffer
2354  * @sender_uaddr	user address in source buffer
2355  * @length		bytes to copy
2356  * @node		list node
2357  *
2358  * This is used for the sg copy list (sgc) which is created and consumed
2359  * during binder_transaction() and is only accessed locally. No
2360  * locking is necessary.
2361  *
2362  * The list is ordered by @offset.
2363  */
2364 struct binder_sg_copy {
2365 	binder_size_t offset;
2366 	const void __user *sender_uaddr;
2367 	size_t length;
2368 	struct list_head node;
2369 };
2370 
2371 /**
2372  * binder_do_deferred_txn_copies() - copy and fixup scatter-gather data
2373  * @alloc:	binder_alloc associated with @buffer
2374  * @buffer:	binder buffer in target process
2375  * @sgc_head:	list_head of scatter-gather copy list
2376  * @pf_head:	list_head of pointer fixup list
2377  *
2378  * Processes all elements of @sgc_head, applying fixups from @pf_head
2379  * and copying the scatter-gather data from the source process' user
2380  * buffer to the target's buffer. It is expected that the list creation
2381  * and processing all occurs during binder_transaction() so these lists
2382  * are only accessed in local context.
2383  *
2384  * Return: 0=success, else -errno
2385  */
binder_do_deferred_txn_copies(struct binder_alloc * alloc,struct binder_buffer * buffer,struct list_head * sgc_head,struct list_head * pf_head)2386 static int binder_do_deferred_txn_copies(struct binder_alloc *alloc,
2387 					 struct binder_buffer *buffer,
2388 					 struct list_head *sgc_head,
2389 					 struct list_head *pf_head)
2390 {
2391 	int ret = 0;
2392 	struct binder_sg_copy *sgc, *tmpsgc;
2393 	struct binder_ptr_fixup *tmppf;
2394 	struct binder_ptr_fixup *pf =
2395 		list_first_entry_or_null(pf_head, struct binder_ptr_fixup,
2396 					 node);
2397 
2398 	list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) {
2399 		size_t bytes_copied = 0;
2400 
2401 		while (bytes_copied < sgc->length) {
2402 			size_t copy_size;
2403 			size_t bytes_left = sgc->length - bytes_copied;
2404 			size_t offset = sgc->offset + bytes_copied;
2405 
2406 			/*
2407 			 * We copy up to the fixup (pointed to by pf)
2408 			 */
2409 			copy_size = pf ? min(bytes_left, (size_t)pf->offset - offset)
2410 				       : bytes_left;
2411 			if (!ret && copy_size)
2412 				ret = binder_alloc_copy_user_to_buffer(
2413 						alloc, buffer,
2414 						offset,
2415 						sgc->sender_uaddr + bytes_copied,
2416 						copy_size);
2417 			bytes_copied += copy_size;
2418 			if (copy_size != bytes_left) {
2419 				BUG_ON(!pf);
2420 				/* we stopped at a fixup offset */
2421 				if (pf->skip_size) {
2422 					/*
2423 					 * we are just skipping. This is for
2424 					 * BINDER_TYPE_FDA where the translated
2425 					 * fds will be fixed up when we get
2426 					 * to target context.
2427 					 */
2428 					bytes_copied += pf->skip_size;
2429 				} else {
2430 					/* apply the fixup indicated by pf */
2431 					if (!ret)
2432 						ret = binder_alloc_copy_to_buffer(
2433 							alloc, buffer,
2434 							pf->offset,
2435 							&pf->fixup_data,
2436 							sizeof(pf->fixup_data));
2437 					bytes_copied += sizeof(pf->fixup_data);
2438 				}
2439 				list_del(&pf->node);
2440 				kfree(pf);
2441 				pf = list_first_entry_or_null(pf_head,
2442 						struct binder_ptr_fixup, node);
2443 			}
2444 		}
2445 		list_del(&sgc->node);
2446 		kfree(sgc);
2447 	}
2448 	list_for_each_entry_safe(pf, tmppf, pf_head, node) {
2449 		BUG_ON(pf->skip_size == 0);
2450 		list_del(&pf->node);
2451 		kfree(pf);
2452 	}
2453 	BUG_ON(!list_empty(sgc_head));
2454 
2455 	return ret > 0 ? -EINVAL : ret;
2456 }
2457 
2458 /**
2459  * binder_cleanup_deferred_txn_lists() - free specified lists
2460  * @sgc_head:	list_head of scatter-gather copy list
2461  * @pf_head:	list_head of pointer fixup list
2462  *
2463  * Called to clean up @sgc_head and @pf_head if there is an
2464  * error.
2465  */
binder_cleanup_deferred_txn_lists(struct list_head * sgc_head,struct list_head * pf_head)2466 static void binder_cleanup_deferred_txn_lists(struct list_head *sgc_head,
2467 					      struct list_head *pf_head)
2468 {
2469 	struct binder_sg_copy *sgc, *tmpsgc;
2470 	struct binder_ptr_fixup *pf, *tmppf;
2471 
2472 	list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) {
2473 		list_del(&sgc->node);
2474 		kfree(sgc);
2475 	}
2476 	list_for_each_entry_safe(pf, tmppf, pf_head, node) {
2477 		list_del(&pf->node);
2478 		kfree(pf);
2479 	}
2480 }
2481 
2482 /**
2483  * binder_defer_copy() - queue a scatter-gather buffer for copy
2484  * @sgc_head:		list_head of scatter-gather copy list
2485  * @offset:		binder buffer offset in target process
2486  * @sender_uaddr:	user address in source process
2487  * @length:		bytes to copy
2488  *
2489  * Specify a scatter-gather block to be copied. The actual copy must
2490  * be deferred until all the needed fixups are identified and queued.
2491  * Then the copy and fixups are done together so un-translated values
2492  * from the source are never visible in the target buffer.
2493  *
2494  * We are guaranteed that repeated calls to this function will have
2495  * monotonically increasing @offset values so the list will naturally
2496  * be ordered.
2497  *
2498  * Return: 0=success, else -errno
2499  */
binder_defer_copy(struct list_head * sgc_head,binder_size_t offset,const void __user * sender_uaddr,size_t length)2500 static int binder_defer_copy(struct list_head *sgc_head, binder_size_t offset,
2501 			     const void __user *sender_uaddr, size_t length)
2502 {
2503 	struct binder_sg_copy *bc = kzalloc(sizeof(*bc), GFP_KERNEL);
2504 
2505 	if (!bc)
2506 		return -ENOMEM;
2507 
2508 	bc->offset = offset;
2509 	bc->sender_uaddr = sender_uaddr;
2510 	bc->length = length;
2511 	INIT_LIST_HEAD(&bc->node);
2512 
2513 	/*
2514 	 * We are guaranteed that the deferred copies are in-order
2515 	 * so just add to the tail.
2516 	 */
2517 	list_add_tail(&bc->node, sgc_head);
2518 
2519 	return 0;
2520 }
2521 
2522 /**
2523  * binder_add_fixup() - queue a fixup to be applied to sg copy
2524  * @pf_head:	list_head of binder ptr fixup list
2525  * @offset:	binder buffer offset in target process
2526  * @fixup:	bytes to be copied for fixup
2527  * @skip_size:	bytes to skip when copying (fixup will be applied later)
2528  *
2529  * Add the specified fixup to a list ordered by @offset. When copying
2530  * the scatter-gather buffers, the fixup will be copied instead of
2531  * data from the source buffer. For BINDER_TYPE_FDA fixups, the fixup
2532  * will be applied later (in target process context), so we just skip
2533  * the bytes specified by @skip_size. If @skip_size is 0, we copy the
2534  * value in @fixup.
2535  *
2536  * This function is called *mostly* in @offset order, but there are
2537  * exceptions. Since out-of-order inserts are relatively uncommon,
2538  * we insert the new element by searching backward from the tail of
2539  * the list.
2540  *
2541  * Return: 0=success, else -errno
2542  */
binder_add_fixup(struct list_head * pf_head,binder_size_t offset,binder_uintptr_t fixup,size_t skip_size)2543 static int binder_add_fixup(struct list_head *pf_head, binder_size_t offset,
2544 			    binder_uintptr_t fixup, size_t skip_size)
2545 {
2546 	struct binder_ptr_fixup *pf = kzalloc(sizeof(*pf), GFP_KERNEL);
2547 	struct binder_ptr_fixup *tmppf;
2548 
2549 	if (!pf)
2550 		return -ENOMEM;
2551 
2552 	pf->offset = offset;
2553 	pf->fixup_data = fixup;
2554 	pf->skip_size = skip_size;
2555 	INIT_LIST_HEAD(&pf->node);
2556 
2557 	/* Fixups are *mostly* added in-order, but there are some
2558 	 * exceptions. Look backwards through list for insertion point.
2559 	 */
2560 	list_for_each_entry_reverse(tmppf, pf_head, node) {
2561 		if (tmppf->offset < pf->offset) {
2562 			list_add(&pf->node, &tmppf->node);
2563 			return 0;
2564 		}
2565 	}
2566 	/*
2567 	 * if we get here, then the new offset is the lowest so
2568 	 * insert at the head
2569 	 */
2570 	list_add(&pf->node, pf_head);
2571 	return 0;
2572 }
2573 
binder_translate_fd_array(struct list_head * pf_head,struct binder_fd_array_object * fda,const void __user * sender_ubuffer,struct binder_buffer_object * parent,struct binder_buffer_object * sender_uparent,struct binder_transaction * t,struct binder_thread * thread,struct binder_transaction * in_reply_to)2574 static int binder_translate_fd_array(struct list_head *pf_head,
2575 				     struct binder_fd_array_object *fda,
2576 				     const void __user *sender_ubuffer,
2577 				     struct binder_buffer_object *parent,
2578 				     struct binder_buffer_object *sender_uparent,
2579 				     struct binder_transaction *t,
2580 				     struct binder_thread *thread,
2581 				     struct binder_transaction *in_reply_to)
2582 {
2583 	binder_size_t fdi, fd_buf_size;
2584 	binder_size_t fda_offset;
2585 	const void __user *sender_ufda_base;
2586 	struct binder_proc *proc = thread->proc;
2587 	int ret;
2588 
2589 	if (fda->num_fds == 0)
2590 		return 0;
2591 
2592 	fd_buf_size = sizeof(u32) * fda->num_fds;
2593 	if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
2594 		binder_user_error("%d:%d got transaction with invalid number of fds (%lld)\n",
2595 				  proc->pid, thread->pid, (u64)fda->num_fds);
2596 		return -EINVAL;
2597 	}
2598 	if (fd_buf_size > parent->length ||
2599 	    fda->parent_offset > parent->length - fd_buf_size) {
2600 		/* No space for all file descriptors here. */
2601 		binder_user_error("%d:%d not enough space to store %lld fds in buffer\n",
2602 				  proc->pid, thread->pid, (u64)fda->num_fds);
2603 		return -EINVAL;
2604 	}
2605 	/*
2606 	 * the source data for binder_buffer_object is visible
2607 	 * to user-space and the @buffer element is the user
2608 	 * pointer to the buffer_object containing the fd_array.
2609 	 * Convert the address to an offset relative to
2610 	 * the base of the transaction buffer.
2611 	 */
2612 	fda_offset = (parent->buffer - (uintptr_t)t->buffer->user_data) +
2613 		fda->parent_offset;
2614 	sender_ufda_base = (void __user *)(uintptr_t)sender_uparent->buffer +
2615 				fda->parent_offset;
2616 
2617 	if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32)) ||
2618 	    !IS_ALIGNED((unsigned long)sender_ufda_base, sizeof(u32))) {
2619 		binder_user_error("%d:%d parent offset not aligned correctly.\n",
2620 				  proc->pid, thread->pid);
2621 		return -EINVAL;
2622 	}
2623 	ret = binder_add_fixup(pf_head, fda_offset, 0, fda->num_fds * sizeof(u32));
2624 	if (ret)
2625 		return ret;
2626 
2627 	for (fdi = 0; fdi < fda->num_fds; fdi++) {
2628 		u32 fd;
2629 		binder_size_t offset = fda_offset + fdi * sizeof(fd);
2630 		binder_size_t sender_uoffset = fdi * sizeof(fd);
2631 
2632 		ret = copy_from_user(&fd, sender_ufda_base + sender_uoffset, sizeof(fd));
2633 		if (!ret)
2634 			ret = binder_translate_fd(fd, offset, t, thread,
2635 						  in_reply_to);
2636 		if (ret)
2637 			return ret > 0 ? -EINVAL : ret;
2638 	}
2639 	return 0;
2640 }
2641 
binder_fixup_parent(struct list_head * pf_head,struct binder_transaction * t,struct binder_thread * thread,struct binder_buffer_object * bp,binder_size_t off_start_offset,binder_size_t num_valid,binder_size_t last_fixup_obj_off,binder_size_t last_fixup_min_off)2642 static int binder_fixup_parent(struct list_head *pf_head,
2643 			       struct binder_transaction *t,
2644 			       struct binder_thread *thread,
2645 			       struct binder_buffer_object *bp,
2646 			       binder_size_t off_start_offset,
2647 			       binder_size_t num_valid,
2648 			       binder_size_t last_fixup_obj_off,
2649 			       binder_size_t last_fixup_min_off)
2650 {
2651 	struct binder_buffer_object *parent;
2652 	struct binder_buffer *b = t->buffer;
2653 	struct binder_proc *proc = thread->proc;
2654 	struct binder_proc *target_proc = t->to_proc;
2655 	struct binder_object object;
2656 	binder_size_t buffer_offset;
2657 	binder_size_t parent_offset;
2658 
2659 	if (!(bp->flags & BINDER_BUFFER_FLAG_HAS_PARENT))
2660 		return 0;
2661 
2662 	parent = binder_validate_ptr(target_proc, b, &object, bp->parent,
2663 				     off_start_offset, &parent_offset,
2664 				     num_valid);
2665 	if (!parent) {
2666 		binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
2667 				  proc->pid, thread->pid);
2668 		return -EINVAL;
2669 	}
2670 
2671 	if (!binder_validate_fixup(target_proc, b, off_start_offset,
2672 				   parent_offset, bp->parent_offset,
2673 				   last_fixup_obj_off,
2674 				   last_fixup_min_off)) {
2675 		binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
2676 				  proc->pid, thread->pid);
2677 		return -EINVAL;
2678 	}
2679 
2680 	if (parent->length < sizeof(binder_uintptr_t) ||
2681 	    bp->parent_offset > parent->length - sizeof(binder_uintptr_t)) {
2682 		/* No space for a pointer here! */
2683 		binder_user_error("%d:%d got transaction with invalid parent offset\n",
2684 				  proc->pid, thread->pid);
2685 		return -EINVAL;
2686 	}
2687 	buffer_offset = bp->parent_offset +
2688 			(uintptr_t)parent->buffer - (uintptr_t)b->user_data;
2689 	return binder_add_fixup(pf_head, buffer_offset, bp->buffer, 0);
2690 }
2691 
2692 /**
2693  * binder_can_update_transaction() - Can a txn be superseded by an updated one?
2694  * @t1: the pending async txn in the frozen process
2695  * @t2: the new async txn to supersede the outdated pending one
2696  *
2697  * Return:  true if t2 can supersede t1
2698  *          false if t2 can not supersede t1
2699  */
binder_can_update_transaction(struct binder_transaction * t1,struct binder_transaction * t2)2700 static bool binder_can_update_transaction(struct binder_transaction *t1,
2701 					  struct binder_transaction *t2)
2702 {
2703 	if ((t1->flags & t2->flags & (TF_ONE_WAY | TF_UPDATE_TXN)) !=
2704 	    (TF_ONE_WAY | TF_UPDATE_TXN) || !t1->to_proc || !t2->to_proc)
2705 		return false;
2706 	if (t1->to_proc->tsk == t2->to_proc->tsk && t1->code == t2->code &&
2707 	    t1->flags == t2->flags && t1->buffer->pid == t2->buffer->pid &&
2708 	    t1->buffer->target_node->ptr == t2->buffer->target_node->ptr &&
2709 	    t1->buffer->target_node->cookie == t2->buffer->target_node->cookie)
2710 		return true;
2711 	return false;
2712 }
2713 
2714 /**
2715  * binder_find_outdated_transaction_ilocked() - Find the outdated transaction
2716  * @t:		 new async transaction
2717  * @target_list: list to find outdated transaction
2718  *
2719  * Return: the outdated transaction if found
2720  *         NULL if no outdated transacton can be found
2721  *
2722  * Requires the proc->inner_lock to be held.
2723  */
2724 static struct binder_transaction *
binder_find_outdated_transaction_ilocked(struct binder_transaction * t,struct list_head * target_list)2725 binder_find_outdated_transaction_ilocked(struct binder_transaction *t,
2726 					 struct list_head *target_list)
2727 {
2728 	struct binder_work *w;
2729 
2730 	list_for_each_entry(w, target_list, entry) {
2731 		struct binder_transaction *t_queued;
2732 
2733 		if (w->type != BINDER_WORK_TRANSACTION)
2734 			continue;
2735 		t_queued = container_of(w, struct binder_transaction, work);
2736 		if (binder_can_update_transaction(t_queued, t))
2737 			return t_queued;
2738 	}
2739 	return NULL;
2740 }
2741 
2742 /**
2743  * binder_proc_transaction() - sends a transaction to a process and wakes it up
2744  * @t:		transaction to send
2745  * @proc:	process to send the transaction to
2746  * @thread:	thread in @proc to send the transaction to (may be NULL)
2747  *
2748  * This function queues a transaction to the specified process. It will try
2749  * to find a thread in the target process to handle the transaction and
2750  * wake it up. If no thread is found, the work is queued to the proc
2751  * waitqueue.
2752  *
2753  * If the @thread parameter is not NULL, the transaction is always queued
2754  * to the waitlist of that specific thread.
2755  *
2756  * Return:	0 if the transaction was successfully queued
2757  *		BR_DEAD_REPLY if the target process or thread is dead
2758  *		BR_FROZEN_REPLY if the target process or thread is frozen and
2759  *			the sync transaction was rejected
2760  *		BR_TRANSACTION_PENDING_FROZEN if the target process is frozen
2761  *		and the async transaction was successfully queued
2762  */
binder_proc_transaction(struct binder_transaction * t,struct binder_proc * proc,struct binder_thread * thread)2763 static int binder_proc_transaction(struct binder_transaction *t,
2764 				    struct binder_proc *proc,
2765 				    struct binder_thread *thread)
2766 {
2767 	struct binder_node *node = t->buffer->target_node;
2768 	bool oneway = !!(t->flags & TF_ONE_WAY);
2769 	bool pending_async = false;
2770 	struct binder_transaction *t_outdated = NULL;
2771 	bool frozen = false;
2772 
2773 	BUG_ON(!node);
2774 	binder_node_lock(node);
2775 	if (oneway) {
2776 		BUG_ON(thread);
2777 		if (node->has_async_transaction)
2778 			pending_async = true;
2779 		else
2780 			node->has_async_transaction = true;
2781 	}
2782 
2783 	binder_inner_proc_lock(proc);
2784 	if (proc->is_frozen) {
2785 		frozen = true;
2786 		proc->sync_recv |= !oneway;
2787 		proc->async_recv |= oneway;
2788 	}
2789 
2790 	if ((frozen && !oneway) || proc->is_dead ||
2791 			(thread && thread->is_dead)) {
2792 		binder_inner_proc_unlock(proc);
2793 		binder_node_unlock(node);
2794 		return frozen ? BR_FROZEN_REPLY : BR_DEAD_REPLY;
2795 	}
2796 
2797 	if (!thread && !pending_async)
2798 		thread = binder_select_thread_ilocked(proc);
2799 
2800 	if (thread) {
2801 		binder_enqueue_thread_work_ilocked(thread, &t->work);
2802 	} else if (!pending_async) {
2803 		binder_enqueue_work_ilocked(&t->work, &proc->todo);
2804 	} else {
2805 		if ((t->flags & TF_UPDATE_TXN) && frozen) {
2806 			t_outdated = binder_find_outdated_transaction_ilocked(t,
2807 									      &node->async_todo);
2808 			if (t_outdated) {
2809 				binder_debug(BINDER_DEBUG_TRANSACTION,
2810 					     "txn %d supersedes %d\n",
2811 					     t->debug_id, t_outdated->debug_id);
2812 				list_del_init(&t_outdated->work.entry);
2813 				proc->outstanding_txns--;
2814 			}
2815 		}
2816 		binder_enqueue_work_ilocked(&t->work, &node->async_todo);
2817 	}
2818 
2819 	if (!pending_async)
2820 		binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */);
2821 
2822 	proc->outstanding_txns++;
2823 	binder_inner_proc_unlock(proc);
2824 	binder_node_unlock(node);
2825 
2826 	/*
2827 	 * To reduce potential contention, free the outdated transaction and
2828 	 * buffer after releasing the locks.
2829 	 */
2830 	if (t_outdated) {
2831 		struct binder_buffer *buffer = t_outdated->buffer;
2832 
2833 		t_outdated->buffer = NULL;
2834 		buffer->transaction = NULL;
2835 		trace_binder_transaction_update_buffer_release(buffer);
2836 		binder_release_entire_buffer(proc, NULL, buffer, false);
2837 		binder_alloc_free_buf(&proc->alloc, buffer);
2838 		kfree(t_outdated);
2839 		binder_stats_deleted(BINDER_STAT_TRANSACTION);
2840 	}
2841 
2842 	if (oneway && frozen)
2843 		return BR_TRANSACTION_PENDING_FROZEN;
2844 
2845 	return 0;
2846 }
2847 
2848 /**
2849  * binder_get_node_refs_for_txn() - Get required refs on node for txn
2850  * @node:         struct binder_node for which to get refs
2851  * @procp:        returns @node->proc if valid
2852  * @error:        if no @procp then returns BR_DEAD_REPLY
2853  *
2854  * User-space normally keeps the node alive when creating a transaction
2855  * since it has a reference to the target. The local strong ref keeps it
2856  * alive if the sending process dies before the target process processes
2857  * the transaction. If the source process is malicious or has a reference
2858  * counting bug, relying on the local strong ref can fail.
2859  *
2860  * Since user-space can cause the local strong ref to go away, we also take
2861  * a tmpref on the node to ensure it survives while we are constructing
2862  * the transaction. We also need a tmpref on the proc while we are
2863  * constructing the transaction, so we take that here as well.
2864  *
2865  * Return: The target_node with refs taken or NULL if no @node->proc is NULL.
2866  * Also sets @procp if valid. If the @node->proc is NULL indicating that the
2867  * target proc has died, @error is set to BR_DEAD_REPLY.
2868  */
binder_get_node_refs_for_txn(struct binder_node * node,struct binder_proc ** procp,uint32_t * error)2869 static struct binder_node *binder_get_node_refs_for_txn(
2870 		struct binder_node *node,
2871 		struct binder_proc **procp,
2872 		uint32_t *error)
2873 {
2874 	struct binder_node *target_node = NULL;
2875 
2876 	binder_node_inner_lock(node);
2877 	if (node->proc) {
2878 		target_node = node;
2879 		binder_inc_node_nilocked(node, 1, 0, NULL);
2880 		binder_inc_node_tmpref_ilocked(node);
2881 		node->proc->tmp_ref++;
2882 		*procp = node->proc;
2883 	} else
2884 		*error = BR_DEAD_REPLY;
2885 	binder_node_inner_unlock(node);
2886 
2887 	return target_node;
2888 }
2889 
binder_set_txn_from_error(struct binder_transaction * t,int id,uint32_t command,int32_t param)2890 static void binder_set_txn_from_error(struct binder_transaction *t, int id,
2891 				      uint32_t command, int32_t param)
2892 {
2893 	struct binder_thread *from = binder_get_txn_from_and_acq_inner(t);
2894 
2895 	if (!from) {
2896 		/* annotation for sparse */
2897 		__release(&from->proc->inner_lock);
2898 		return;
2899 	}
2900 
2901 	/* don't override existing errors */
2902 	if (from->ee.command == BR_OK)
2903 		binder_set_extended_error(&from->ee, id, command, param);
2904 	binder_inner_proc_unlock(from->proc);
2905 	binder_thread_dec_tmpref(from);
2906 }
2907 
binder_transaction(struct binder_proc * proc,struct binder_thread * thread,struct binder_transaction_data * tr,int reply,binder_size_t extra_buffers_size)2908 static void binder_transaction(struct binder_proc *proc,
2909 			       struct binder_thread *thread,
2910 			       struct binder_transaction_data *tr, int reply,
2911 			       binder_size_t extra_buffers_size)
2912 {
2913 	int ret;
2914 	struct binder_transaction *t;
2915 	struct binder_work *w;
2916 	struct binder_work *tcomplete;
2917 	binder_size_t buffer_offset = 0;
2918 	binder_size_t off_start_offset, off_end_offset;
2919 	binder_size_t off_min;
2920 	binder_size_t sg_buf_offset, sg_buf_end_offset;
2921 	binder_size_t user_offset = 0;
2922 	struct binder_proc *target_proc = NULL;
2923 	struct binder_thread *target_thread = NULL;
2924 	struct binder_node *target_node = NULL;
2925 	struct binder_transaction *in_reply_to = NULL;
2926 	struct binder_transaction_log_entry *e;
2927 	uint32_t return_error = 0;
2928 	uint32_t return_error_param = 0;
2929 	uint32_t return_error_line = 0;
2930 	binder_size_t last_fixup_obj_off = 0;
2931 	binder_size_t last_fixup_min_off = 0;
2932 	struct binder_context *context = proc->context;
2933 	int t_debug_id = atomic_inc_return(&binder_last_id);
2934 	ktime_t t_start_time = ktime_get();
2935 	char *secctx = NULL;
2936 	u32 secctx_sz = 0;
2937 	struct list_head sgc_head;
2938 	struct list_head pf_head;
2939 	const void __user *user_buffer = (const void __user *)
2940 				(uintptr_t)tr->data.ptr.buffer;
2941 	INIT_LIST_HEAD(&sgc_head);
2942 	INIT_LIST_HEAD(&pf_head);
2943 
2944 	e = binder_transaction_log_add(&binder_transaction_log);
2945 	e->debug_id = t_debug_id;
2946 	e->call_type = reply ? 2 : !!(tr->flags & TF_ONE_WAY);
2947 	e->from_proc = proc->pid;
2948 	e->from_thread = thread->pid;
2949 	e->target_handle = tr->target.handle;
2950 	e->data_size = tr->data_size;
2951 	e->offsets_size = tr->offsets_size;
2952 	strscpy(e->context_name, proc->context->name, BINDERFS_MAX_NAME);
2953 
2954 	binder_inner_proc_lock(proc);
2955 	binder_set_extended_error(&thread->ee, t_debug_id, BR_OK, 0);
2956 	binder_inner_proc_unlock(proc);
2957 
2958 	if (reply) {
2959 		binder_inner_proc_lock(proc);
2960 		in_reply_to = thread->transaction_stack;
2961 		if (in_reply_to == NULL) {
2962 			binder_inner_proc_unlock(proc);
2963 			binder_user_error("%d:%d got reply transaction with no transaction stack\n",
2964 					  proc->pid, thread->pid);
2965 			return_error = BR_FAILED_REPLY;
2966 			return_error_param = -EPROTO;
2967 			return_error_line = __LINE__;
2968 			goto err_empty_call_stack;
2969 		}
2970 		if (in_reply_to->to_thread != thread) {
2971 			spin_lock(&in_reply_to->lock);
2972 			binder_user_error("%d:%d got reply transaction with bad transaction stack, transaction %d has target %d:%d\n",
2973 				proc->pid, thread->pid, in_reply_to->debug_id,
2974 				in_reply_to->to_proc ?
2975 				in_reply_to->to_proc->pid : 0,
2976 				in_reply_to->to_thread ?
2977 				in_reply_to->to_thread->pid : 0);
2978 			spin_unlock(&in_reply_to->lock);
2979 			binder_inner_proc_unlock(proc);
2980 			return_error = BR_FAILED_REPLY;
2981 			return_error_param = -EPROTO;
2982 			return_error_line = __LINE__;
2983 			in_reply_to = NULL;
2984 			goto err_bad_call_stack;
2985 		}
2986 		thread->transaction_stack = in_reply_to->to_parent;
2987 		binder_inner_proc_unlock(proc);
2988 		binder_set_nice(in_reply_to->saved_priority);
2989 		target_thread = binder_get_txn_from_and_acq_inner(in_reply_to);
2990 		if (target_thread == NULL) {
2991 			/* annotation for sparse */
2992 			__release(&target_thread->proc->inner_lock);
2993 			binder_txn_error("%d:%d reply target not found\n",
2994 				thread->pid, proc->pid);
2995 			return_error = BR_DEAD_REPLY;
2996 			return_error_line = __LINE__;
2997 			goto err_dead_binder;
2998 		}
2999 		if (target_thread->transaction_stack != in_reply_to) {
3000 			binder_user_error("%d:%d got reply transaction with bad target transaction stack %d, expected %d\n",
3001 				proc->pid, thread->pid,
3002 				target_thread->transaction_stack ?
3003 				target_thread->transaction_stack->debug_id : 0,
3004 				in_reply_to->debug_id);
3005 			binder_inner_proc_unlock(target_thread->proc);
3006 			return_error = BR_FAILED_REPLY;
3007 			return_error_param = -EPROTO;
3008 			return_error_line = __LINE__;
3009 			in_reply_to = NULL;
3010 			target_thread = NULL;
3011 			goto err_dead_binder;
3012 		}
3013 		target_proc = target_thread->proc;
3014 		target_proc->tmp_ref++;
3015 		binder_inner_proc_unlock(target_thread->proc);
3016 	} else {
3017 		if (tr->target.handle) {
3018 			struct binder_ref *ref;
3019 
3020 			/*
3021 			 * There must already be a strong ref
3022 			 * on this node. If so, do a strong
3023 			 * increment on the node to ensure it
3024 			 * stays alive until the transaction is
3025 			 * done.
3026 			 */
3027 			binder_proc_lock(proc);
3028 			ref = binder_get_ref_olocked(proc, tr->target.handle,
3029 						     true);
3030 			if (ref) {
3031 				target_node = binder_get_node_refs_for_txn(
3032 						ref->node, &target_proc,
3033 						&return_error);
3034 			} else {
3035 				binder_user_error("%d:%d got transaction to invalid handle, %u\n",
3036 						  proc->pid, thread->pid, tr->target.handle);
3037 				return_error = BR_FAILED_REPLY;
3038 			}
3039 			binder_proc_unlock(proc);
3040 		} else {
3041 			mutex_lock(&context->context_mgr_node_lock);
3042 			target_node = context->binder_context_mgr_node;
3043 			if (target_node)
3044 				target_node = binder_get_node_refs_for_txn(
3045 						target_node, &target_proc,
3046 						&return_error);
3047 			else
3048 				return_error = BR_DEAD_REPLY;
3049 			mutex_unlock(&context->context_mgr_node_lock);
3050 			if (target_node && target_proc->pid == proc->pid) {
3051 				binder_user_error("%d:%d got transaction to context manager from process owning it\n",
3052 						  proc->pid, thread->pid);
3053 				return_error = BR_FAILED_REPLY;
3054 				return_error_param = -EINVAL;
3055 				return_error_line = __LINE__;
3056 				goto err_invalid_target_handle;
3057 			}
3058 		}
3059 		if (!target_node) {
3060 			binder_txn_error("%d:%d cannot find target node\n",
3061 				thread->pid, proc->pid);
3062 			/*
3063 			 * return_error is set above
3064 			 */
3065 			return_error_param = -EINVAL;
3066 			return_error_line = __LINE__;
3067 			goto err_dead_binder;
3068 		}
3069 		e->to_node = target_node->debug_id;
3070 		if (WARN_ON(proc == target_proc)) {
3071 			binder_txn_error("%d:%d self transactions not allowed\n",
3072 				thread->pid, proc->pid);
3073 			return_error = BR_FAILED_REPLY;
3074 			return_error_param = -EINVAL;
3075 			return_error_line = __LINE__;
3076 			goto err_invalid_target_handle;
3077 		}
3078 		if (security_binder_transaction(proc->cred,
3079 						target_proc->cred) < 0) {
3080 			binder_txn_error("%d:%d transaction credentials failed\n",
3081 				thread->pid, proc->pid);
3082 			return_error = BR_FAILED_REPLY;
3083 			return_error_param = -EPERM;
3084 			return_error_line = __LINE__;
3085 			goto err_invalid_target_handle;
3086 		}
3087 		binder_inner_proc_lock(proc);
3088 
3089 		w = list_first_entry_or_null(&thread->todo,
3090 					     struct binder_work, entry);
3091 		if (!(tr->flags & TF_ONE_WAY) && w &&
3092 		    w->type == BINDER_WORK_TRANSACTION) {
3093 			/*
3094 			 * Do not allow new outgoing transaction from a
3095 			 * thread that has a transaction at the head of
3096 			 * its todo list. Only need to check the head
3097 			 * because binder_select_thread_ilocked picks a
3098 			 * thread from proc->waiting_threads to enqueue
3099 			 * the transaction, and nothing is queued to the
3100 			 * todo list while the thread is on waiting_threads.
3101 			 */
3102 			binder_user_error("%d:%d new transaction not allowed when there is a transaction on thread todo\n",
3103 					  proc->pid, thread->pid);
3104 			binder_inner_proc_unlock(proc);
3105 			return_error = BR_FAILED_REPLY;
3106 			return_error_param = -EPROTO;
3107 			return_error_line = __LINE__;
3108 			goto err_bad_todo_list;
3109 		}
3110 
3111 		if (!(tr->flags & TF_ONE_WAY) && thread->transaction_stack) {
3112 			struct binder_transaction *tmp;
3113 
3114 			tmp = thread->transaction_stack;
3115 			if (tmp->to_thread != thread) {
3116 				spin_lock(&tmp->lock);
3117 				binder_user_error("%d:%d got new transaction with bad transaction stack, transaction %d has target %d:%d\n",
3118 					proc->pid, thread->pid, tmp->debug_id,
3119 					tmp->to_proc ? tmp->to_proc->pid : 0,
3120 					tmp->to_thread ?
3121 					tmp->to_thread->pid : 0);
3122 				spin_unlock(&tmp->lock);
3123 				binder_inner_proc_unlock(proc);
3124 				return_error = BR_FAILED_REPLY;
3125 				return_error_param = -EPROTO;
3126 				return_error_line = __LINE__;
3127 				goto err_bad_call_stack;
3128 			}
3129 			while (tmp) {
3130 				struct binder_thread *from;
3131 
3132 				spin_lock(&tmp->lock);
3133 				from = tmp->from;
3134 				if (from && from->proc == target_proc) {
3135 					atomic_inc(&from->tmp_ref);
3136 					target_thread = from;
3137 					spin_unlock(&tmp->lock);
3138 					break;
3139 				}
3140 				spin_unlock(&tmp->lock);
3141 				tmp = tmp->from_parent;
3142 			}
3143 		}
3144 		binder_inner_proc_unlock(proc);
3145 	}
3146 	if (target_thread)
3147 		e->to_thread = target_thread->pid;
3148 	e->to_proc = target_proc->pid;
3149 
3150 	/* TODO: reuse incoming transaction for reply */
3151 	t = kzalloc(sizeof(*t), GFP_KERNEL);
3152 	if (t == NULL) {
3153 		binder_txn_error("%d:%d cannot allocate transaction\n",
3154 			thread->pid, proc->pid);
3155 		return_error = BR_FAILED_REPLY;
3156 		return_error_param = -ENOMEM;
3157 		return_error_line = __LINE__;
3158 		goto err_alloc_t_failed;
3159 	}
3160 	INIT_LIST_HEAD(&t->fd_fixups);
3161 	binder_stats_created(BINDER_STAT_TRANSACTION);
3162 	spin_lock_init(&t->lock);
3163 
3164 	tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL);
3165 	if (tcomplete == NULL) {
3166 		binder_txn_error("%d:%d cannot allocate work for transaction\n",
3167 			thread->pid, proc->pid);
3168 		return_error = BR_FAILED_REPLY;
3169 		return_error_param = -ENOMEM;
3170 		return_error_line = __LINE__;
3171 		goto err_alloc_tcomplete_failed;
3172 	}
3173 	binder_stats_created(BINDER_STAT_TRANSACTION_COMPLETE);
3174 
3175 	t->debug_id = t_debug_id;
3176 	t->start_time = t_start_time;
3177 
3178 	if (reply)
3179 		binder_debug(BINDER_DEBUG_TRANSACTION,
3180 			     "%d:%d BC_REPLY %d -> %d:%d, data %016llx-%016llx size %lld-%lld-%lld\n",
3181 			     proc->pid, thread->pid, t->debug_id,
3182 			     target_proc->pid, target_thread->pid,
3183 			     (u64)tr->data.ptr.buffer,
3184 			     (u64)tr->data.ptr.offsets,
3185 			     (u64)tr->data_size, (u64)tr->offsets_size,
3186 			     (u64)extra_buffers_size);
3187 	else
3188 		binder_debug(BINDER_DEBUG_TRANSACTION,
3189 			     "%d:%d BC_TRANSACTION %d -> %d - node %d, data %016llx-%016llx size %lld-%lld-%lld\n",
3190 			     proc->pid, thread->pid, t->debug_id,
3191 			     target_proc->pid, target_node->debug_id,
3192 			     (u64)tr->data.ptr.buffer,
3193 			     (u64)tr->data.ptr.offsets,
3194 			     (u64)tr->data_size, (u64)tr->offsets_size,
3195 			     (u64)extra_buffers_size);
3196 
3197 	if (!reply && !(tr->flags & TF_ONE_WAY))
3198 		t->from = thread;
3199 	else
3200 		t->from = NULL;
3201 	t->from_pid = proc->pid;
3202 	t->from_tid = thread->pid;
3203 	t->sender_euid = task_euid(proc->tsk);
3204 	t->to_proc = target_proc;
3205 	t->to_thread = target_thread;
3206 	t->code = tr->code;
3207 	t->flags = tr->flags;
3208 	t->priority = task_nice(current);
3209 
3210 	if (target_node && target_node->txn_security_ctx) {
3211 		u32 secid;
3212 		size_t added_size;
3213 
3214 		security_cred_getsecid(proc->cred, &secid);
3215 		ret = security_secid_to_secctx(secid, &secctx, &secctx_sz);
3216 		if (ret) {
3217 			binder_txn_error("%d:%d failed to get security context\n",
3218 				thread->pid, proc->pid);
3219 			return_error = BR_FAILED_REPLY;
3220 			return_error_param = ret;
3221 			return_error_line = __LINE__;
3222 			goto err_get_secctx_failed;
3223 		}
3224 		added_size = ALIGN(secctx_sz, sizeof(u64));
3225 		extra_buffers_size += added_size;
3226 		if (extra_buffers_size < added_size) {
3227 			binder_txn_error("%d:%d integer overflow of extra_buffers_size\n",
3228 				thread->pid, proc->pid);
3229 			return_error = BR_FAILED_REPLY;
3230 			return_error_param = -EINVAL;
3231 			return_error_line = __LINE__;
3232 			goto err_bad_extra_size;
3233 		}
3234 	}
3235 
3236 	trace_binder_transaction(reply, t, target_node);
3237 
3238 	t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size,
3239 		tr->offsets_size, extra_buffers_size,
3240 		!reply && (t->flags & TF_ONE_WAY), current->tgid);
3241 	if (IS_ERR(t->buffer)) {
3242 		char *s;
3243 
3244 		ret = PTR_ERR(t->buffer);
3245 		s = (ret == -ESRCH) ? ": vma cleared, target dead or dying"
3246 			: (ret == -ENOSPC) ? ": no space left"
3247 			: (ret == -ENOMEM) ? ": memory allocation failed"
3248 			: "";
3249 		binder_txn_error("cannot allocate buffer%s", s);
3250 
3251 		return_error_param = PTR_ERR(t->buffer);
3252 		return_error = return_error_param == -ESRCH ?
3253 			BR_DEAD_REPLY : BR_FAILED_REPLY;
3254 		return_error_line = __LINE__;
3255 		t->buffer = NULL;
3256 		goto err_binder_alloc_buf_failed;
3257 	}
3258 	if (secctx) {
3259 		int err;
3260 		size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
3261 				    ALIGN(tr->offsets_size, sizeof(void *)) +
3262 				    ALIGN(extra_buffers_size, sizeof(void *)) -
3263 				    ALIGN(secctx_sz, sizeof(u64));
3264 
3265 		t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset;
3266 		err = binder_alloc_copy_to_buffer(&target_proc->alloc,
3267 						  t->buffer, buf_offset,
3268 						  secctx, secctx_sz);
3269 		if (err) {
3270 			t->security_ctx = 0;
3271 			WARN_ON(1);
3272 		}
3273 		security_release_secctx(secctx, secctx_sz);
3274 		secctx = NULL;
3275 	}
3276 	t->buffer->debug_id = t->debug_id;
3277 	t->buffer->transaction = t;
3278 	t->buffer->target_node = target_node;
3279 	t->buffer->clear_on_free = !!(t->flags & TF_CLEAR_BUF);
3280 	trace_binder_transaction_alloc_buf(t->buffer);
3281 
3282 	if (binder_alloc_copy_user_to_buffer(
3283 				&target_proc->alloc,
3284 				t->buffer,
3285 				ALIGN(tr->data_size, sizeof(void *)),
3286 				(const void __user *)
3287 					(uintptr_t)tr->data.ptr.offsets,
3288 				tr->offsets_size)) {
3289 		binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
3290 				proc->pid, thread->pid);
3291 		return_error = BR_FAILED_REPLY;
3292 		return_error_param = -EFAULT;
3293 		return_error_line = __LINE__;
3294 		goto err_copy_data_failed;
3295 	}
3296 	if (!IS_ALIGNED(tr->offsets_size, sizeof(binder_size_t))) {
3297 		binder_user_error("%d:%d got transaction with invalid offsets size, %lld\n",
3298 				proc->pid, thread->pid, (u64)tr->offsets_size);
3299 		return_error = BR_FAILED_REPLY;
3300 		return_error_param = -EINVAL;
3301 		return_error_line = __LINE__;
3302 		goto err_bad_offset;
3303 	}
3304 	if (!IS_ALIGNED(extra_buffers_size, sizeof(u64))) {
3305 		binder_user_error("%d:%d got transaction with unaligned buffers size, %lld\n",
3306 				  proc->pid, thread->pid,
3307 				  (u64)extra_buffers_size);
3308 		return_error = BR_FAILED_REPLY;
3309 		return_error_param = -EINVAL;
3310 		return_error_line = __LINE__;
3311 		goto err_bad_offset;
3312 	}
3313 	off_start_offset = ALIGN(tr->data_size, sizeof(void *));
3314 	buffer_offset = off_start_offset;
3315 	off_end_offset = off_start_offset + tr->offsets_size;
3316 	sg_buf_offset = ALIGN(off_end_offset, sizeof(void *));
3317 	sg_buf_end_offset = sg_buf_offset + extra_buffers_size -
3318 		ALIGN(secctx_sz, sizeof(u64));
3319 	off_min = 0;
3320 	for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
3321 	     buffer_offset += sizeof(binder_size_t)) {
3322 		struct binder_object_header *hdr;
3323 		size_t object_size;
3324 		struct binder_object object;
3325 		binder_size_t object_offset;
3326 		binder_size_t copy_size;
3327 
3328 		if (binder_alloc_copy_from_buffer(&target_proc->alloc,
3329 						  &object_offset,
3330 						  t->buffer,
3331 						  buffer_offset,
3332 						  sizeof(object_offset))) {
3333 			binder_txn_error("%d:%d copy offset from buffer failed\n",
3334 				thread->pid, proc->pid);
3335 			return_error = BR_FAILED_REPLY;
3336 			return_error_param = -EINVAL;
3337 			return_error_line = __LINE__;
3338 			goto err_bad_offset;
3339 		}
3340 
3341 		/*
3342 		 * Copy the source user buffer up to the next object
3343 		 * that will be processed.
3344 		 */
3345 		copy_size = object_offset - user_offset;
3346 		if (copy_size && (user_offset > object_offset ||
3347 				binder_alloc_copy_user_to_buffer(
3348 					&target_proc->alloc,
3349 					t->buffer, user_offset,
3350 					user_buffer + user_offset,
3351 					copy_size))) {
3352 			binder_user_error("%d:%d got transaction with invalid data ptr\n",
3353 					proc->pid, thread->pid);
3354 			return_error = BR_FAILED_REPLY;
3355 			return_error_param = -EFAULT;
3356 			return_error_line = __LINE__;
3357 			goto err_copy_data_failed;
3358 		}
3359 		object_size = binder_get_object(target_proc, user_buffer,
3360 				t->buffer, object_offset, &object);
3361 		if (object_size == 0 || object_offset < off_min) {
3362 			binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n",
3363 					  proc->pid, thread->pid,
3364 					  (u64)object_offset,
3365 					  (u64)off_min,
3366 					  (u64)t->buffer->data_size);
3367 			return_error = BR_FAILED_REPLY;
3368 			return_error_param = -EINVAL;
3369 			return_error_line = __LINE__;
3370 			goto err_bad_offset;
3371 		}
3372 		/*
3373 		 * Set offset to the next buffer fragment to be
3374 		 * copied
3375 		 */
3376 		user_offset = object_offset + object_size;
3377 
3378 		hdr = &object.hdr;
3379 		off_min = object_offset + object_size;
3380 		switch (hdr->type) {
3381 		case BINDER_TYPE_BINDER:
3382 		case BINDER_TYPE_WEAK_BINDER: {
3383 			struct flat_binder_object *fp;
3384 
3385 			fp = to_flat_binder_object(hdr);
3386 			ret = binder_translate_binder(fp, t, thread);
3387 
3388 			if (ret < 0 ||
3389 			    binder_alloc_copy_to_buffer(&target_proc->alloc,
3390 							t->buffer,
3391 							object_offset,
3392 							fp, sizeof(*fp))) {
3393 				binder_txn_error("%d:%d translate binder failed\n",
3394 					thread->pid, proc->pid);
3395 				return_error = BR_FAILED_REPLY;
3396 				return_error_param = ret;
3397 				return_error_line = __LINE__;
3398 				goto err_translate_failed;
3399 			}
3400 		} break;
3401 		case BINDER_TYPE_HANDLE:
3402 		case BINDER_TYPE_WEAK_HANDLE: {
3403 			struct flat_binder_object *fp;
3404 
3405 			fp = to_flat_binder_object(hdr);
3406 			ret = binder_translate_handle(fp, t, thread);
3407 			if (ret < 0 ||
3408 			    binder_alloc_copy_to_buffer(&target_proc->alloc,
3409 							t->buffer,
3410 							object_offset,
3411 							fp, sizeof(*fp))) {
3412 				binder_txn_error("%d:%d translate handle failed\n",
3413 					thread->pid, proc->pid);
3414 				return_error = BR_FAILED_REPLY;
3415 				return_error_param = ret;
3416 				return_error_line = __LINE__;
3417 				goto err_translate_failed;
3418 			}
3419 		} break;
3420 
3421 		case BINDER_TYPE_FD: {
3422 			struct binder_fd_object *fp = to_binder_fd_object(hdr);
3423 			binder_size_t fd_offset = object_offset +
3424 				(uintptr_t)&fp->fd - (uintptr_t)fp;
3425 			int ret = binder_translate_fd(fp->fd, fd_offset, t,
3426 						      thread, in_reply_to);
3427 
3428 			fp->pad_binder = 0;
3429 			if (ret < 0 ||
3430 			    binder_alloc_copy_to_buffer(&target_proc->alloc,
3431 							t->buffer,
3432 							object_offset,
3433 							fp, sizeof(*fp))) {
3434 				binder_txn_error("%d:%d translate fd failed\n",
3435 					thread->pid, proc->pid);
3436 				return_error = BR_FAILED_REPLY;
3437 				return_error_param = ret;
3438 				return_error_line = __LINE__;
3439 				goto err_translate_failed;
3440 			}
3441 		} break;
3442 		case BINDER_TYPE_FDA: {
3443 			struct binder_object ptr_object;
3444 			binder_size_t parent_offset;
3445 			struct binder_object user_object;
3446 			size_t user_parent_size;
3447 			struct binder_fd_array_object *fda =
3448 				to_binder_fd_array_object(hdr);
3449 			size_t num_valid = (buffer_offset - off_start_offset) /
3450 						sizeof(binder_size_t);
3451 			struct binder_buffer_object *parent =
3452 				binder_validate_ptr(target_proc, t->buffer,
3453 						    &ptr_object, fda->parent,
3454 						    off_start_offset,
3455 						    &parent_offset,
3456 						    num_valid);
3457 			if (!parent) {
3458 				binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
3459 						  proc->pid, thread->pid);
3460 				return_error = BR_FAILED_REPLY;
3461 				return_error_param = -EINVAL;
3462 				return_error_line = __LINE__;
3463 				goto err_bad_parent;
3464 			}
3465 			if (!binder_validate_fixup(target_proc, t->buffer,
3466 						   off_start_offset,
3467 						   parent_offset,
3468 						   fda->parent_offset,
3469 						   last_fixup_obj_off,
3470 						   last_fixup_min_off)) {
3471 				binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
3472 						  proc->pid, thread->pid);
3473 				return_error = BR_FAILED_REPLY;
3474 				return_error_param = -EINVAL;
3475 				return_error_line = __LINE__;
3476 				goto err_bad_parent;
3477 			}
3478 			/*
3479 			 * We need to read the user version of the parent
3480 			 * object to get the original user offset
3481 			 */
3482 			user_parent_size =
3483 				binder_get_object(proc, user_buffer, t->buffer,
3484 						  parent_offset, &user_object);
3485 			if (user_parent_size != sizeof(user_object.bbo)) {
3486 				binder_user_error("%d:%d invalid ptr object size: %zd vs %zd\n",
3487 						  proc->pid, thread->pid,
3488 						  user_parent_size,
3489 						  sizeof(user_object.bbo));
3490 				return_error = BR_FAILED_REPLY;
3491 				return_error_param = -EINVAL;
3492 				return_error_line = __LINE__;
3493 				goto err_bad_parent;
3494 			}
3495 			ret = binder_translate_fd_array(&pf_head, fda,
3496 							user_buffer, parent,
3497 							&user_object.bbo, t,
3498 							thread, in_reply_to);
3499 			if (!ret)
3500 				ret = binder_alloc_copy_to_buffer(&target_proc->alloc,
3501 								  t->buffer,
3502 								  object_offset,
3503 								  fda, sizeof(*fda));
3504 			if (ret) {
3505 				binder_txn_error("%d:%d translate fd array failed\n",
3506 					thread->pid, proc->pid);
3507 				return_error = BR_FAILED_REPLY;
3508 				return_error_param = ret > 0 ? -EINVAL : ret;
3509 				return_error_line = __LINE__;
3510 				goto err_translate_failed;
3511 			}
3512 			last_fixup_obj_off = parent_offset;
3513 			last_fixup_min_off =
3514 				fda->parent_offset + sizeof(u32) * fda->num_fds;
3515 		} break;
3516 		case BINDER_TYPE_PTR: {
3517 			struct binder_buffer_object *bp =
3518 				to_binder_buffer_object(hdr);
3519 			size_t buf_left = sg_buf_end_offset - sg_buf_offset;
3520 			size_t num_valid;
3521 
3522 			if (bp->length > buf_left) {
3523 				binder_user_error("%d:%d got transaction with too large buffer\n",
3524 						  proc->pid, thread->pid);
3525 				return_error = BR_FAILED_REPLY;
3526 				return_error_param = -EINVAL;
3527 				return_error_line = __LINE__;
3528 				goto err_bad_offset;
3529 			}
3530 			ret = binder_defer_copy(&sgc_head, sg_buf_offset,
3531 				(const void __user *)(uintptr_t)bp->buffer,
3532 				bp->length);
3533 			if (ret) {
3534 				binder_txn_error("%d:%d deferred copy failed\n",
3535 					thread->pid, proc->pid);
3536 				return_error = BR_FAILED_REPLY;
3537 				return_error_param = ret;
3538 				return_error_line = __LINE__;
3539 				goto err_translate_failed;
3540 			}
3541 			/* Fixup buffer pointer to target proc address space */
3542 			bp->buffer = (uintptr_t)
3543 				t->buffer->user_data + sg_buf_offset;
3544 			sg_buf_offset += ALIGN(bp->length, sizeof(u64));
3545 
3546 			num_valid = (buffer_offset - off_start_offset) /
3547 					sizeof(binder_size_t);
3548 			ret = binder_fixup_parent(&pf_head, t,
3549 						  thread, bp,
3550 						  off_start_offset,
3551 						  num_valid,
3552 						  last_fixup_obj_off,
3553 						  last_fixup_min_off);
3554 			if (ret < 0 ||
3555 			    binder_alloc_copy_to_buffer(&target_proc->alloc,
3556 							t->buffer,
3557 							object_offset,
3558 							bp, sizeof(*bp))) {
3559 				binder_txn_error("%d:%d failed to fixup parent\n",
3560 					thread->pid, proc->pid);
3561 				return_error = BR_FAILED_REPLY;
3562 				return_error_param = ret;
3563 				return_error_line = __LINE__;
3564 				goto err_translate_failed;
3565 			}
3566 			last_fixup_obj_off = object_offset;
3567 			last_fixup_min_off = 0;
3568 		} break;
3569 		default:
3570 			binder_user_error("%d:%d got transaction with invalid object type, %x\n",
3571 				proc->pid, thread->pid, hdr->type);
3572 			return_error = BR_FAILED_REPLY;
3573 			return_error_param = -EINVAL;
3574 			return_error_line = __LINE__;
3575 			goto err_bad_object_type;
3576 		}
3577 	}
3578 	/* Done processing objects, copy the rest of the buffer */
3579 	if (binder_alloc_copy_user_to_buffer(
3580 				&target_proc->alloc,
3581 				t->buffer, user_offset,
3582 				user_buffer + user_offset,
3583 				tr->data_size - user_offset)) {
3584 		binder_user_error("%d:%d got transaction with invalid data ptr\n",
3585 				proc->pid, thread->pid);
3586 		return_error = BR_FAILED_REPLY;
3587 		return_error_param = -EFAULT;
3588 		return_error_line = __LINE__;
3589 		goto err_copy_data_failed;
3590 	}
3591 
3592 	ret = binder_do_deferred_txn_copies(&target_proc->alloc, t->buffer,
3593 					    &sgc_head, &pf_head);
3594 	if (ret) {
3595 		binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
3596 				  proc->pid, thread->pid);
3597 		return_error = BR_FAILED_REPLY;
3598 		return_error_param = ret;
3599 		return_error_line = __LINE__;
3600 		goto err_copy_data_failed;
3601 	}
3602 	if (t->buffer->oneway_spam_suspect)
3603 		tcomplete->type = BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT;
3604 	else
3605 		tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
3606 	t->work.type = BINDER_WORK_TRANSACTION;
3607 
3608 	if (reply) {
3609 		binder_enqueue_thread_work(thread, tcomplete);
3610 		binder_inner_proc_lock(target_proc);
3611 		if (target_thread->is_dead) {
3612 			return_error = BR_DEAD_REPLY;
3613 			binder_inner_proc_unlock(target_proc);
3614 			goto err_dead_proc_or_thread;
3615 		}
3616 		BUG_ON(t->buffer->async_transaction != 0);
3617 		binder_pop_transaction_ilocked(target_thread, in_reply_to);
3618 		binder_enqueue_thread_work_ilocked(target_thread, &t->work);
3619 		target_proc->outstanding_txns++;
3620 		binder_inner_proc_unlock(target_proc);
3621 		wake_up_interruptible_sync(&target_thread->wait);
3622 		binder_free_transaction(in_reply_to);
3623 	} else if (!(t->flags & TF_ONE_WAY)) {
3624 		BUG_ON(t->buffer->async_transaction != 0);
3625 		binder_inner_proc_lock(proc);
3626 		/*
3627 		 * Defer the TRANSACTION_COMPLETE, so we don't return to
3628 		 * userspace immediately; this allows the target process to
3629 		 * immediately start processing this transaction, reducing
3630 		 * latency. We will then return the TRANSACTION_COMPLETE when
3631 		 * the target replies (or there is an error).
3632 		 */
3633 		binder_enqueue_deferred_thread_work_ilocked(thread, tcomplete);
3634 		t->need_reply = 1;
3635 		t->from_parent = thread->transaction_stack;
3636 		thread->transaction_stack = t;
3637 		binder_inner_proc_unlock(proc);
3638 		return_error = binder_proc_transaction(t,
3639 				target_proc, target_thread);
3640 		if (return_error) {
3641 			binder_inner_proc_lock(proc);
3642 			binder_pop_transaction_ilocked(thread, t);
3643 			binder_inner_proc_unlock(proc);
3644 			goto err_dead_proc_or_thread;
3645 		}
3646 	} else {
3647 		BUG_ON(target_node == NULL);
3648 		BUG_ON(t->buffer->async_transaction != 1);
3649 		return_error = binder_proc_transaction(t, target_proc, NULL);
3650 		/*
3651 		 * Let the caller know when async transaction reaches a frozen
3652 		 * process and is put in a pending queue, waiting for the target
3653 		 * process to be unfrozen.
3654 		 */
3655 		if (return_error == BR_TRANSACTION_PENDING_FROZEN)
3656 			tcomplete->type = BINDER_WORK_TRANSACTION_PENDING;
3657 		binder_enqueue_thread_work(thread, tcomplete);
3658 		if (return_error &&
3659 		    return_error != BR_TRANSACTION_PENDING_FROZEN)
3660 			goto err_dead_proc_or_thread;
3661 	}
3662 	if (target_thread)
3663 		binder_thread_dec_tmpref(target_thread);
3664 	binder_proc_dec_tmpref(target_proc);
3665 	if (target_node)
3666 		binder_dec_node_tmpref(target_node);
3667 	/*
3668 	 * write barrier to synchronize with initialization
3669 	 * of log entry
3670 	 */
3671 	smp_wmb();
3672 	WRITE_ONCE(e->debug_id_done, t_debug_id);
3673 	return;
3674 
3675 err_dead_proc_or_thread:
3676 	binder_txn_error("%d:%d dead process or thread\n",
3677 		thread->pid, proc->pid);
3678 	return_error_line = __LINE__;
3679 	binder_dequeue_work(proc, tcomplete);
3680 err_translate_failed:
3681 err_bad_object_type:
3682 err_bad_offset:
3683 err_bad_parent:
3684 err_copy_data_failed:
3685 	binder_cleanup_deferred_txn_lists(&sgc_head, &pf_head);
3686 	binder_free_txn_fixups(t);
3687 	trace_binder_transaction_failed_buffer_release(t->buffer);
3688 	binder_transaction_buffer_release(target_proc, NULL, t->buffer,
3689 					  buffer_offset, true);
3690 	if (target_node)
3691 		binder_dec_node_tmpref(target_node);
3692 	target_node = NULL;
3693 	t->buffer->transaction = NULL;
3694 	binder_alloc_free_buf(&target_proc->alloc, t->buffer);
3695 err_binder_alloc_buf_failed:
3696 err_bad_extra_size:
3697 	if (secctx)
3698 		security_release_secctx(secctx, secctx_sz);
3699 err_get_secctx_failed:
3700 	kfree(tcomplete);
3701 	binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
3702 err_alloc_tcomplete_failed:
3703 	if (trace_binder_txn_latency_free_enabled())
3704 		binder_txn_latency_free(t);
3705 	kfree(t);
3706 	binder_stats_deleted(BINDER_STAT_TRANSACTION);
3707 err_alloc_t_failed:
3708 err_bad_todo_list:
3709 err_bad_call_stack:
3710 err_empty_call_stack:
3711 err_dead_binder:
3712 err_invalid_target_handle:
3713 	if (target_node) {
3714 		binder_dec_node(target_node, 1, 0);
3715 		binder_dec_node_tmpref(target_node);
3716 	}
3717 
3718 	binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
3719 		     "%d:%d transaction %s to %d:%d failed %d/%d/%d, size %lld-%lld line %d\n",
3720 		     proc->pid, thread->pid, reply ? "reply" :
3721 		     (tr->flags & TF_ONE_WAY ? "async" : "call"),
3722 		     target_proc ? target_proc->pid : 0,
3723 		     target_thread ? target_thread->pid : 0,
3724 		     t_debug_id, return_error, return_error_param,
3725 		     (u64)tr->data_size, (u64)tr->offsets_size,
3726 		     return_error_line);
3727 
3728 	if (target_thread)
3729 		binder_thread_dec_tmpref(target_thread);
3730 	if (target_proc)
3731 		binder_proc_dec_tmpref(target_proc);
3732 
3733 	{
3734 		struct binder_transaction_log_entry *fe;
3735 
3736 		e->return_error = return_error;
3737 		e->return_error_param = return_error_param;
3738 		e->return_error_line = return_error_line;
3739 		fe = binder_transaction_log_add(&binder_transaction_log_failed);
3740 		*fe = *e;
3741 		/*
3742 		 * write barrier to synchronize with initialization
3743 		 * of log entry
3744 		 */
3745 		smp_wmb();
3746 		WRITE_ONCE(e->debug_id_done, t_debug_id);
3747 		WRITE_ONCE(fe->debug_id_done, t_debug_id);
3748 	}
3749 
3750 	BUG_ON(thread->return_error.cmd != BR_OK);
3751 	if (in_reply_to) {
3752 		binder_set_txn_from_error(in_reply_to, t_debug_id,
3753 				return_error, return_error_param);
3754 		thread->return_error.cmd = BR_TRANSACTION_COMPLETE;
3755 		binder_enqueue_thread_work(thread, &thread->return_error.work);
3756 		binder_send_failed_reply(in_reply_to, return_error);
3757 	} else {
3758 		binder_inner_proc_lock(proc);
3759 		binder_set_extended_error(&thread->ee, t_debug_id,
3760 				return_error, return_error_param);
3761 		binder_inner_proc_unlock(proc);
3762 		thread->return_error.cmd = return_error;
3763 		binder_enqueue_thread_work(thread, &thread->return_error.work);
3764 	}
3765 }
3766 
3767 /**
3768  * binder_free_buf() - free the specified buffer
3769  * @proc:	binder proc that owns buffer
3770  * @buffer:	buffer to be freed
3771  * @is_failure:	failed to send transaction
3772  *
3773  * If buffer for an async transaction, enqueue the next async
3774  * transaction from the node.
3775  *
3776  * Cleanup buffer and free it.
3777  */
3778 static void
binder_free_buf(struct binder_proc * proc,struct binder_thread * thread,struct binder_buffer * buffer,bool is_failure)3779 binder_free_buf(struct binder_proc *proc,
3780 		struct binder_thread *thread,
3781 		struct binder_buffer *buffer, bool is_failure)
3782 {
3783 	binder_inner_proc_lock(proc);
3784 	if (buffer->transaction) {
3785 		buffer->transaction->buffer = NULL;
3786 		buffer->transaction = NULL;
3787 	}
3788 	binder_inner_proc_unlock(proc);
3789 	if (buffer->async_transaction && buffer->target_node) {
3790 		struct binder_node *buf_node;
3791 		struct binder_work *w;
3792 
3793 		buf_node = buffer->target_node;
3794 		binder_node_inner_lock(buf_node);
3795 		BUG_ON(!buf_node->has_async_transaction);
3796 		BUG_ON(buf_node->proc != proc);
3797 		w = binder_dequeue_work_head_ilocked(
3798 				&buf_node->async_todo);
3799 		if (!w) {
3800 			buf_node->has_async_transaction = false;
3801 		} else {
3802 			binder_enqueue_work_ilocked(
3803 					w, &proc->todo);
3804 			binder_wakeup_proc_ilocked(proc);
3805 		}
3806 		binder_node_inner_unlock(buf_node);
3807 	}
3808 	trace_binder_transaction_buffer_release(buffer);
3809 	binder_release_entire_buffer(proc, thread, buffer, is_failure);
3810 	binder_alloc_free_buf(&proc->alloc, buffer);
3811 }
3812 
binder_thread_write(struct binder_proc * proc,struct binder_thread * thread,binder_uintptr_t binder_buffer,size_t size,binder_size_t * consumed)3813 static int binder_thread_write(struct binder_proc *proc,
3814 			struct binder_thread *thread,
3815 			binder_uintptr_t binder_buffer, size_t size,
3816 			binder_size_t *consumed)
3817 {
3818 	uint32_t cmd;
3819 	struct binder_context *context = proc->context;
3820 	void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
3821 	void __user *ptr = buffer + *consumed;
3822 	void __user *end = buffer + size;
3823 
3824 	while (ptr < end && thread->return_error.cmd == BR_OK) {
3825 		int ret;
3826 
3827 		if (get_user(cmd, (uint32_t __user *)ptr))
3828 			return -EFAULT;
3829 		ptr += sizeof(uint32_t);
3830 		trace_binder_command(cmd);
3831 		if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.bc)) {
3832 			atomic_inc(&binder_stats.bc[_IOC_NR(cmd)]);
3833 			atomic_inc(&proc->stats.bc[_IOC_NR(cmd)]);
3834 			atomic_inc(&thread->stats.bc[_IOC_NR(cmd)]);
3835 		}
3836 		switch (cmd) {
3837 		case BC_INCREFS:
3838 		case BC_ACQUIRE:
3839 		case BC_RELEASE:
3840 		case BC_DECREFS: {
3841 			uint32_t target;
3842 			const char *debug_string;
3843 			bool strong = cmd == BC_ACQUIRE || cmd == BC_RELEASE;
3844 			bool increment = cmd == BC_INCREFS || cmd == BC_ACQUIRE;
3845 			struct binder_ref_data rdata;
3846 
3847 			if (get_user(target, (uint32_t __user *)ptr))
3848 				return -EFAULT;
3849 
3850 			ptr += sizeof(uint32_t);
3851 			ret = -1;
3852 			if (increment && !target) {
3853 				struct binder_node *ctx_mgr_node;
3854 
3855 				mutex_lock(&context->context_mgr_node_lock);
3856 				ctx_mgr_node = context->binder_context_mgr_node;
3857 				if (ctx_mgr_node) {
3858 					if (ctx_mgr_node->proc == proc) {
3859 						binder_user_error("%d:%d context manager tried to acquire desc 0\n",
3860 								  proc->pid, thread->pid);
3861 						mutex_unlock(&context->context_mgr_node_lock);
3862 						return -EINVAL;
3863 					}
3864 					ret = binder_inc_ref_for_node(
3865 							proc, ctx_mgr_node,
3866 							strong, NULL, &rdata);
3867 				}
3868 				mutex_unlock(&context->context_mgr_node_lock);
3869 			}
3870 			if (ret)
3871 				ret = binder_update_ref_for_handle(
3872 						proc, target, increment, strong,
3873 						&rdata);
3874 			if (!ret && rdata.desc != target) {
3875 				binder_user_error("%d:%d tried to acquire reference to desc %d, got %d instead\n",
3876 					proc->pid, thread->pid,
3877 					target, rdata.desc);
3878 			}
3879 			switch (cmd) {
3880 			case BC_INCREFS:
3881 				debug_string = "IncRefs";
3882 				break;
3883 			case BC_ACQUIRE:
3884 				debug_string = "Acquire";
3885 				break;
3886 			case BC_RELEASE:
3887 				debug_string = "Release";
3888 				break;
3889 			case BC_DECREFS:
3890 			default:
3891 				debug_string = "DecRefs";
3892 				break;
3893 			}
3894 			if (ret) {
3895 				binder_user_error("%d:%d %s %d refcount change on invalid ref %d ret %d\n",
3896 					proc->pid, thread->pid, debug_string,
3897 					strong, target, ret);
3898 				break;
3899 			}
3900 			binder_debug(BINDER_DEBUG_USER_REFS,
3901 				     "%d:%d %s ref %d desc %d s %d w %d\n",
3902 				     proc->pid, thread->pid, debug_string,
3903 				     rdata.debug_id, rdata.desc, rdata.strong,
3904 				     rdata.weak);
3905 			break;
3906 		}
3907 		case BC_INCREFS_DONE:
3908 		case BC_ACQUIRE_DONE: {
3909 			binder_uintptr_t node_ptr;
3910 			binder_uintptr_t cookie;
3911 			struct binder_node *node;
3912 			bool free_node;
3913 
3914 			if (get_user(node_ptr, (binder_uintptr_t __user *)ptr))
3915 				return -EFAULT;
3916 			ptr += sizeof(binder_uintptr_t);
3917 			if (get_user(cookie, (binder_uintptr_t __user *)ptr))
3918 				return -EFAULT;
3919 			ptr += sizeof(binder_uintptr_t);
3920 			node = binder_get_node(proc, node_ptr);
3921 			if (node == NULL) {
3922 				binder_user_error("%d:%d %s u%016llx no match\n",
3923 					proc->pid, thread->pid,
3924 					cmd == BC_INCREFS_DONE ?
3925 					"BC_INCREFS_DONE" :
3926 					"BC_ACQUIRE_DONE",
3927 					(u64)node_ptr);
3928 				break;
3929 			}
3930 			if (cookie != node->cookie) {
3931 				binder_user_error("%d:%d %s u%016llx node %d cookie mismatch %016llx != %016llx\n",
3932 					proc->pid, thread->pid,
3933 					cmd == BC_INCREFS_DONE ?
3934 					"BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
3935 					(u64)node_ptr, node->debug_id,
3936 					(u64)cookie, (u64)node->cookie);
3937 				binder_put_node(node);
3938 				break;
3939 			}
3940 			binder_node_inner_lock(node);
3941 			if (cmd == BC_ACQUIRE_DONE) {
3942 				if (node->pending_strong_ref == 0) {
3943 					binder_user_error("%d:%d BC_ACQUIRE_DONE node %d has no pending acquire request\n",
3944 						proc->pid, thread->pid,
3945 						node->debug_id);
3946 					binder_node_inner_unlock(node);
3947 					binder_put_node(node);
3948 					break;
3949 				}
3950 				node->pending_strong_ref = 0;
3951 			} else {
3952 				if (node->pending_weak_ref == 0) {
3953 					binder_user_error("%d:%d BC_INCREFS_DONE node %d has no pending increfs request\n",
3954 						proc->pid, thread->pid,
3955 						node->debug_id);
3956 					binder_node_inner_unlock(node);
3957 					binder_put_node(node);
3958 					break;
3959 				}
3960 				node->pending_weak_ref = 0;
3961 			}
3962 			free_node = binder_dec_node_nilocked(node,
3963 					cmd == BC_ACQUIRE_DONE, 0);
3964 			WARN_ON(free_node);
3965 			binder_debug(BINDER_DEBUG_USER_REFS,
3966 				     "%d:%d %s node %d ls %d lw %d tr %d\n",
3967 				     proc->pid, thread->pid,
3968 				     cmd == BC_INCREFS_DONE ? "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
3969 				     node->debug_id, node->local_strong_refs,
3970 				     node->local_weak_refs, node->tmp_refs);
3971 			binder_node_inner_unlock(node);
3972 			binder_put_node(node);
3973 			break;
3974 		}
3975 		case BC_ATTEMPT_ACQUIRE:
3976 			pr_err("BC_ATTEMPT_ACQUIRE not supported\n");
3977 			return -EINVAL;
3978 		case BC_ACQUIRE_RESULT:
3979 			pr_err("BC_ACQUIRE_RESULT not supported\n");
3980 			return -EINVAL;
3981 
3982 		case BC_FREE_BUFFER: {
3983 			binder_uintptr_t data_ptr;
3984 			struct binder_buffer *buffer;
3985 
3986 			if (get_user(data_ptr, (binder_uintptr_t __user *)ptr))
3987 				return -EFAULT;
3988 			ptr += sizeof(binder_uintptr_t);
3989 
3990 			buffer = binder_alloc_prepare_to_free(&proc->alloc,
3991 							      data_ptr);
3992 			if (IS_ERR_OR_NULL(buffer)) {
3993 				if (PTR_ERR(buffer) == -EPERM) {
3994 					binder_user_error(
3995 						"%d:%d BC_FREE_BUFFER u%016llx matched unreturned or currently freeing buffer\n",
3996 						proc->pid, thread->pid,
3997 						(u64)data_ptr);
3998 				} else {
3999 					binder_user_error(
4000 						"%d:%d BC_FREE_BUFFER u%016llx no match\n",
4001 						proc->pid, thread->pid,
4002 						(u64)data_ptr);
4003 				}
4004 				break;
4005 			}
4006 			binder_debug(BINDER_DEBUG_FREE_BUFFER,
4007 				     "%d:%d BC_FREE_BUFFER u%016llx found buffer %d for %s transaction\n",
4008 				     proc->pid, thread->pid, (u64)data_ptr,
4009 				     buffer->debug_id,
4010 				     buffer->transaction ? "active" : "finished");
4011 			binder_free_buf(proc, thread, buffer, false);
4012 			break;
4013 		}
4014 
4015 		case BC_TRANSACTION_SG:
4016 		case BC_REPLY_SG: {
4017 			struct binder_transaction_data_sg tr;
4018 
4019 			if (copy_from_user(&tr, ptr, sizeof(tr)))
4020 				return -EFAULT;
4021 			ptr += sizeof(tr);
4022 			binder_transaction(proc, thread, &tr.transaction_data,
4023 					   cmd == BC_REPLY_SG, tr.buffers_size);
4024 			break;
4025 		}
4026 		case BC_TRANSACTION:
4027 		case BC_REPLY: {
4028 			struct binder_transaction_data tr;
4029 
4030 			if (copy_from_user(&tr, ptr, sizeof(tr)))
4031 				return -EFAULT;
4032 			ptr += sizeof(tr);
4033 			binder_transaction(proc, thread, &tr,
4034 					   cmd == BC_REPLY, 0);
4035 			break;
4036 		}
4037 
4038 		case BC_REGISTER_LOOPER:
4039 			binder_debug(BINDER_DEBUG_THREADS,
4040 				     "%d:%d BC_REGISTER_LOOPER\n",
4041 				     proc->pid, thread->pid);
4042 			binder_inner_proc_lock(proc);
4043 			if (thread->looper & BINDER_LOOPER_STATE_ENTERED) {
4044 				thread->looper |= BINDER_LOOPER_STATE_INVALID;
4045 				binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called after BC_ENTER_LOOPER\n",
4046 					proc->pid, thread->pid);
4047 			} else if (proc->requested_threads == 0) {
4048 				thread->looper |= BINDER_LOOPER_STATE_INVALID;
4049 				binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called without request\n",
4050 					proc->pid, thread->pid);
4051 			} else {
4052 				proc->requested_threads--;
4053 				proc->requested_threads_started++;
4054 			}
4055 			thread->looper |= BINDER_LOOPER_STATE_REGISTERED;
4056 			binder_inner_proc_unlock(proc);
4057 			break;
4058 		case BC_ENTER_LOOPER:
4059 			binder_debug(BINDER_DEBUG_THREADS,
4060 				     "%d:%d BC_ENTER_LOOPER\n",
4061 				     proc->pid, thread->pid);
4062 			if (thread->looper & BINDER_LOOPER_STATE_REGISTERED) {
4063 				thread->looper |= BINDER_LOOPER_STATE_INVALID;
4064 				binder_user_error("%d:%d ERROR: BC_ENTER_LOOPER called after BC_REGISTER_LOOPER\n",
4065 					proc->pid, thread->pid);
4066 			}
4067 			thread->looper |= BINDER_LOOPER_STATE_ENTERED;
4068 			break;
4069 		case BC_EXIT_LOOPER:
4070 			binder_debug(BINDER_DEBUG_THREADS,
4071 				     "%d:%d BC_EXIT_LOOPER\n",
4072 				     proc->pid, thread->pid);
4073 			thread->looper |= BINDER_LOOPER_STATE_EXITED;
4074 			break;
4075 
4076 		case BC_REQUEST_DEATH_NOTIFICATION:
4077 		case BC_CLEAR_DEATH_NOTIFICATION: {
4078 			uint32_t target;
4079 			binder_uintptr_t cookie;
4080 			struct binder_ref *ref;
4081 			struct binder_ref_death *death = NULL;
4082 
4083 			if (get_user(target, (uint32_t __user *)ptr))
4084 				return -EFAULT;
4085 			ptr += sizeof(uint32_t);
4086 			if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4087 				return -EFAULT;
4088 			ptr += sizeof(binder_uintptr_t);
4089 			if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
4090 				/*
4091 				 * Allocate memory for death notification
4092 				 * before taking lock
4093 				 */
4094 				death = kzalloc(sizeof(*death), GFP_KERNEL);
4095 				if (death == NULL) {
4096 					WARN_ON(thread->return_error.cmd !=
4097 						BR_OK);
4098 					thread->return_error.cmd = BR_ERROR;
4099 					binder_enqueue_thread_work(
4100 						thread,
4101 						&thread->return_error.work);
4102 					binder_debug(
4103 						BINDER_DEBUG_FAILED_TRANSACTION,
4104 						"%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n",
4105 						proc->pid, thread->pid);
4106 					break;
4107 				}
4108 			}
4109 			binder_proc_lock(proc);
4110 			ref = binder_get_ref_olocked(proc, target, false);
4111 			if (ref == NULL) {
4112 				binder_user_error("%d:%d %s invalid ref %d\n",
4113 					proc->pid, thread->pid,
4114 					cmd == BC_REQUEST_DEATH_NOTIFICATION ?
4115 					"BC_REQUEST_DEATH_NOTIFICATION" :
4116 					"BC_CLEAR_DEATH_NOTIFICATION",
4117 					target);
4118 				binder_proc_unlock(proc);
4119 				kfree(death);
4120 				break;
4121 			}
4122 
4123 			binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
4124 				     "%d:%d %s %016llx ref %d desc %d s %d w %d for node %d\n",
4125 				     proc->pid, thread->pid,
4126 				     cmd == BC_REQUEST_DEATH_NOTIFICATION ?
4127 				     "BC_REQUEST_DEATH_NOTIFICATION" :
4128 				     "BC_CLEAR_DEATH_NOTIFICATION",
4129 				     (u64)cookie, ref->data.debug_id,
4130 				     ref->data.desc, ref->data.strong,
4131 				     ref->data.weak, ref->node->debug_id);
4132 
4133 			binder_node_lock(ref->node);
4134 			if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
4135 				if (ref->death) {
4136 					binder_user_error("%d:%d BC_REQUEST_DEATH_NOTIFICATION death notification already set\n",
4137 						proc->pid, thread->pid);
4138 					binder_node_unlock(ref->node);
4139 					binder_proc_unlock(proc);
4140 					kfree(death);
4141 					break;
4142 				}
4143 				binder_stats_created(BINDER_STAT_DEATH);
4144 				INIT_LIST_HEAD(&death->work.entry);
4145 				death->cookie = cookie;
4146 				ref->death = death;
4147 				if (ref->node->proc == NULL) {
4148 					ref->death->work.type = BINDER_WORK_DEAD_BINDER;
4149 
4150 					binder_inner_proc_lock(proc);
4151 					binder_enqueue_work_ilocked(
4152 						&ref->death->work, &proc->todo);
4153 					binder_wakeup_proc_ilocked(proc);
4154 					binder_inner_proc_unlock(proc);
4155 				}
4156 			} else {
4157 				if (ref->death == NULL) {
4158 					binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification not active\n",
4159 						proc->pid, thread->pid);
4160 					binder_node_unlock(ref->node);
4161 					binder_proc_unlock(proc);
4162 					break;
4163 				}
4164 				death = ref->death;
4165 				if (death->cookie != cookie) {
4166 					binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification cookie mismatch %016llx != %016llx\n",
4167 						proc->pid, thread->pid,
4168 						(u64)death->cookie,
4169 						(u64)cookie);
4170 					binder_node_unlock(ref->node);
4171 					binder_proc_unlock(proc);
4172 					break;
4173 				}
4174 				ref->death = NULL;
4175 				binder_inner_proc_lock(proc);
4176 				if (list_empty(&death->work.entry)) {
4177 					death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
4178 					if (thread->looper &
4179 					    (BINDER_LOOPER_STATE_REGISTERED |
4180 					     BINDER_LOOPER_STATE_ENTERED))
4181 						binder_enqueue_thread_work_ilocked(
4182 								thread,
4183 								&death->work);
4184 					else {
4185 						binder_enqueue_work_ilocked(
4186 								&death->work,
4187 								&proc->todo);
4188 						binder_wakeup_proc_ilocked(
4189 								proc);
4190 					}
4191 				} else {
4192 					BUG_ON(death->work.type != BINDER_WORK_DEAD_BINDER);
4193 					death->work.type = BINDER_WORK_DEAD_BINDER_AND_CLEAR;
4194 				}
4195 				binder_inner_proc_unlock(proc);
4196 			}
4197 			binder_node_unlock(ref->node);
4198 			binder_proc_unlock(proc);
4199 		} break;
4200 		case BC_DEAD_BINDER_DONE: {
4201 			struct binder_work *w;
4202 			binder_uintptr_t cookie;
4203 			struct binder_ref_death *death = NULL;
4204 
4205 			if (get_user(cookie, (binder_uintptr_t __user *)ptr))
4206 				return -EFAULT;
4207 
4208 			ptr += sizeof(cookie);
4209 			binder_inner_proc_lock(proc);
4210 			list_for_each_entry(w, &proc->delivered_death,
4211 					    entry) {
4212 				struct binder_ref_death *tmp_death =
4213 					container_of(w,
4214 						     struct binder_ref_death,
4215 						     work);
4216 
4217 				if (tmp_death->cookie == cookie) {
4218 					death = tmp_death;
4219 					break;
4220 				}
4221 			}
4222 			binder_debug(BINDER_DEBUG_DEAD_BINDER,
4223 				     "%d:%d BC_DEAD_BINDER_DONE %016llx found %pK\n",
4224 				     proc->pid, thread->pid, (u64)cookie,
4225 				     death);
4226 			if (death == NULL) {
4227 				binder_user_error("%d:%d BC_DEAD_BINDER_DONE %016llx not found\n",
4228 					proc->pid, thread->pid, (u64)cookie);
4229 				binder_inner_proc_unlock(proc);
4230 				break;
4231 			}
4232 			binder_dequeue_work_ilocked(&death->work);
4233 			if (death->work.type == BINDER_WORK_DEAD_BINDER_AND_CLEAR) {
4234 				death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
4235 				if (thread->looper &
4236 					(BINDER_LOOPER_STATE_REGISTERED |
4237 					 BINDER_LOOPER_STATE_ENTERED))
4238 					binder_enqueue_thread_work_ilocked(
4239 						thread, &death->work);
4240 				else {
4241 					binder_enqueue_work_ilocked(
4242 							&death->work,
4243 							&proc->todo);
4244 					binder_wakeup_proc_ilocked(proc);
4245 				}
4246 			}
4247 			binder_inner_proc_unlock(proc);
4248 		} break;
4249 
4250 		default:
4251 			pr_err("%d:%d unknown command %u\n",
4252 			       proc->pid, thread->pid, cmd);
4253 			return -EINVAL;
4254 		}
4255 		*consumed = ptr - buffer;
4256 	}
4257 	return 0;
4258 }
4259 
binder_stat_br(struct binder_proc * proc,struct binder_thread * thread,uint32_t cmd)4260 static void binder_stat_br(struct binder_proc *proc,
4261 			   struct binder_thread *thread, uint32_t cmd)
4262 {
4263 	trace_binder_return(cmd);
4264 	if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.br)) {
4265 		atomic_inc(&binder_stats.br[_IOC_NR(cmd)]);
4266 		atomic_inc(&proc->stats.br[_IOC_NR(cmd)]);
4267 		atomic_inc(&thread->stats.br[_IOC_NR(cmd)]);
4268 	}
4269 }
4270 
binder_put_node_cmd(struct binder_proc * proc,struct binder_thread * thread,void __user ** ptrp,binder_uintptr_t node_ptr,binder_uintptr_t node_cookie,int node_debug_id,uint32_t cmd,const char * cmd_name)4271 static int binder_put_node_cmd(struct binder_proc *proc,
4272 			       struct binder_thread *thread,
4273 			       void __user **ptrp,
4274 			       binder_uintptr_t node_ptr,
4275 			       binder_uintptr_t node_cookie,
4276 			       int node_debug_id,
4277 			       uint32_t cmd, const char *cmd_name)
4278 {
4279 	void __user *ptr = *ptrp;
4280 
4281 	if (put_user(cmd, (uint32_t __user *)ptr))
4282 		return -EFAULT;
4283 	ptr += sizeof(uint32_t);
4284 
4285 	if (put_user(node_ptr, (binder_uintptr_t __user *)ptr))
4286 		return -EFAULT;
4287 	ptr += sizeof(binder_uintptr_t);
4288 
4289 	if (put_user(node_cookie, (binder_uintptr_t __user *)ptr))
4290 		return -EFAULT;
4291 	ptr += sizeof(binder_uintptr_t);
4292 
4293 	binder_stat_br(proc, thread, cmd);
4294 	binder_debug(BINDER_DEBUG_USER_REFS, "%d:%d %s %d u%016llx c%016llx\n",
4295 		     proc->pid, thread->pid, cmd_name, node_debug_id,
4296 		     (u64)node_ptr, (u64)node_cookie);
4297 
4298 	*ptrp = ptr;
4299 	return 0;
4300 }
4301 
binder_wait_for_work(struct binder_thread * thread,bool do_proc_work)4302 static int binder_wait_for_work(struct binder_thread *thread,
4303 				bool do_proc_work)
4304 {
4305 	DEFINE_WAIT(wait);
4306 	struct binder_proc *proc = thread->proc;
4307 	int ret = 0;
4308 
4309 	binder_inner_proc_lock(proc);
4310 	for (;;) {
4311 		prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE|TASK_FREEZABLE);
4312 		if (binder_has_work_ilocked(thread, do_proc_work))
4313 			break;
4314 		if (do_proc_work)
4315 			list_add(&thread->waiting_thread_node,
4316 				 &proc->waiting_threads);
4317 		binder_inner_proc_unlock(proc);
4318 		schedule();
4319 		binder_inner_proc_lock(proc);
4320 		list_del_init(&thread->waiting_thread_node);
4321 		if (signal_pending(current)) {
4322 			ret = -EINTR;
4323 			break;
4324 		}
4325 	}
4326 	finish_wait(&thread->wait, &wait);
4327 	binder_inner_proc_unlock(proc);
4328 
4329 	return ret;
4330 }
4331 
4332 /**
4333  * binder_apply_fd_fixups() - finish fd translation
4334  * @proc:         binder_proc associated @t->buffer
4335  * @t:	binder transaction with list of fd fixups
4336  *
4337  * Now that we are in the context of the transaction target
4338  * process, we can allocate and install fds. Process the
4339  * list of fds to translate and fixup the buffer with the
4340  * new fds first and only then install the files.
4341  *
4342  * If we fail to allocate an fd, skip the install and release
4343  * any fds that have already been allocated.
4344  */
binder_apply_fd_fixups(struct binder_proc * proc,struct binder_transaction * t)4345 static int binder_apply_fd_fixups(struct binder_proc *proc,
4346 				  struct binder_transaction *t)
4347 {
4348 	struct binder_txn_fd_fixup *fixup, *tmp;
4349 	int ret = 0;
4350 
4351 	list_for_each_entry(fixup, &t->fd_fixups, fixup_entry) {
4352 		int fd = get_unused_fd_flags(O_CLOEXEC);
4353 
4354 		if (fd < 0) {
4355 			binder_debug(BINDER_DEBUG_TRANSACTION,
4356 				     "failed fd fixup txn %d fd %d\n",
4357 				     t->debug_id, fd);
4358 			ret = -ENOMEM;
4359 			goto err;
4360 		}
4361 		binder_debug(BINDER_DEBUG_TRANSACTION,
4362 			     "fd fixup txn %d fd %d\n",
4363 			     t->debug_id, fd);
4364 		trace_binder_transaction_fd_recv(t, fd, fixup->offset);
4365 		fixup->target_fd = fd;
4366 		if (binder_alloc_copy_to_buffer(&proc->alloc, t->buffer,
4367 						fixup->offset, &fd,
4368 						sizeof(u32))) {
4369 			ret = -EINVAL;
4370 			goto err;
4371 		}
4372 	}
4373 	list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
4374 		fd_install(fixup->target_fd, fixup->file);
4375 		list_del(&fixup->fixup_entry);
4376 		kfree(fixup);
4377 	}
4378 
4379 	return ret;
4380 
4381 err:
4382 	binder_free_txn_fixups(t);
4383 	return ret;
4384 }
4385 
binder_thread_read(struct binder_proc * proc,struct binder_thread * thread,binder_uintptr_t binder_buffer,size_t size,binder_size_t * consumed,int non_block)4386 static int binder_thread_read(struct binder_proc *proc,
4387 			      struct binder_thread *thread,
4388 			      binder_uintptr_t binder_buffer, size_t size,
4389 			      binder_size_t *consumed, int non_block)
4390 {
4391 	void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
4392 	void __user *ptr = buffer + *consumed;
4393 	void __user *end = buffer + size;
4394 
4395 	int ret = 0;
4396 	int wait_for_proc_work;
4397 
4398 	if (*consumed == 0) {
4399 		if (put_user(BR_NOOP, (uint32_t __user *)ptr))
4400 			return -EFAULT;
4401 		ptr += sizeof(uint32_t);
4402 	}
4403 
4404 retry:
4405 	binder_inner_proc_lock(proc);
4406 	wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
4407 	binder_inner_proc_unlock(proc);
4408 
4409 	thread->looper |= BINDER_LOOPER_STATE_WAITING;
4410 
4411 	trace_binder_wait_for_work(wait_for_proc_work,
4412 				   !!thread->transaction_stack,
4413 				   !binder_worklist_empty(proc, &thread->todo));
4414 	if (wait_for_proc_work) {
4415 		if (!(thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
4416 					BINDER_LOOPER_STATE_ENTERED))) {
4417 			binder_user_error("%d:%d ERROR: Thread waiting for process work before calling BC_REGISTER_LOOPER or BC_ENTER_LOOPER (state %x)\n",
4418 				proc->pid, thread->pid, thread->looper);
4419 			wait_event_interruptible(binder_user_error_wait,
4420 						 binder_stop_on_user_error < 2);
4421 		}
4422 		binder_set_nice(proc->default_priority);
4423 	}
4424 
4425 	if (non_block) {
4426 		if (!binder_has_work(thread, wait_for_proc_work))
4427 			ret = -EAGAIN;
4428 	} else {
4429 		ret = binder_wait_for_work(thread, wait_for_proc_work);
4430 	}
4431 
4432 	thread->looper &= ~BINDER_LOOPER_STATE_WAITING;
4433 
4434 	if (ret)
4435 		return ret;
4436 
4437 	while (1) {
4438 		uint32_t cmd;
4439 		struct binder_transaction_data_secctx tr;
4440 		struct binder_transaction_data *trd = &tr.transaction_data;
4441 		struct binder_work *w = NULL;
4442 		struct list_head *list = NULL;
4443 		struct binder_transaction *t = NULL;
4444 		struct binder_thread *t_from;
4445 		size_t trsize = sizeof(*trd);
4446 
4447 		binder_inner_proc_lock(proc);
4448 		if (!binder_worklist_empty_ilocked(&thread->todo))
4449 			list = &thread->todo;
4450 		else if (!binder_worklist_empty_ilocked(&proc->todo) &&
4451 			   wait_for_proc_work)
4452 			list = &proc->todo;
4453 		else {
4454 			binder_inner_proc_unlock(proc);
4455 
4456 			/* no data added */
4457 			if (ptr - buffer == 4 && !thread->looper_need_return)
4458 				goto retry;
4459 			break;
4460 		}
4461 
4462 		if (end - ptr < sizeof(tr) + 4) {
4463 			binder_inner_proc_unlock(proc);
4464 			break;
4465 		}
4466 		w = binder_dequeue_work_head_ilocked(list);
4467 		if (binder_worklist_empty_ilocked(&thread->todo))
4468 			thread->process_todo = false;
4469 
4470 		switch (w->type) {
4471 		case BINDER_WORK_TRANSACTION: {
4472 			binder_inner_proc_unlock(proc);
4473 			t = container_of(w, struct binder_transaction, work);
4474 		} break;
4475 		case BINDER_WORK_RETURN_ERROR: {
4476 			struct binder_error *e = container_of(
4477 					w, struct binder_error, work);
4478 
4479 			WARN_ON(e->cmd == BR_OK);
4480 			binder_inner_proc_unlock(proc);
4481 			if (put_user(e->cmd, (uint32_t __user *)ptr))
4482 				return -EFAULT;
4483 			cmd = e->cmd;
4484 			e->cmd = BR_OK;
4485 			ptr += sizeof(uint32_t);
4486 
4487 			binder_stat_br(proc, thread, cmd);
4488 		} break;
4489 		case BINDER_WORK_TRANSACTION_COMPLETE:
4490 		case BINDER_WORK_TRANSACTION_PENDING:
4491 		case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT: {
4492 			if (proc->oneway_spam_detection_enabled &&
4493 				   w->type == BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT)
4494 				cmd = BR_ONEWAY_SPAM_SUSPECT;
4495 			else if (w->type == BINDER_WORK_TRANSACTION_PENDING)
4496 				cmd = BR_TRANSACTION_PENDING_FROZEN;
4497 			else
4498 				cmd = BR_TRANSACTION_COMPLETE;
4499 			binder_inner_proc_unlock(proc);
4500 			kfree(w);
4501 			binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
4502 			if (put_user(cmd, (uint32_t __user *)ptr))
4503 				return -EFAULT;
4504 			ptr += sizeof(uint32_t);
4505 
4506 			binder_stat_br(proc, thread, cmd);
4507 			binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE,
4508 				     "%d:%d BR_TRANSACTION_COMPLETE\n",
4509 				     proc->pid, thread->pid);
4510 		} break;
4511 		case BINDER_WORK_NODE: {
4512 			struct binder_node *node = container_of(w, struct binder_node, work);
4513 			int strong, weak;
4514 			binder_uintptr_t node_ptr = node->ptr;
4515 			binder_uintptr_t node_cookie = node->cookie;
4516 			int node_debug_id = node->debug_id;
4517 			int has_weak_ref;
4518 			int has_strong_ref;
4519 			void __user *orig_ptr = ptr;
4520 
4521 			BUG_ON(proc != node->proc);
4522 			strong = node->internal_strong_refs ||
4523 					node->local_strong_refs;
4524 			weak = !hlist_empty(&node->refs) ||
4525 					node->local_weak_refs ||
4526 					node->tmp_refs || strong;
4527 			has_strong_ref = node->has_strong_ref;
4528 			has_weak_ref = node->has_weak_ref;
4529 
4530 			if (weak && !has_weak_ref) {
4531 				node->has_weak_ref = 1;
4532 				node->pending_weak_ref = 1;
4533 				node->local_weak_refs++;
4534 			}
4535 			if (strong && !has_strong_ref) {
4536 				node->has_strong_ref = 1;
4537 				node->pending_strong_ref = 1;
4538 				node->local_strong_refs++;
4539 			}
4540 			if (!strong && has_strong_ref)
4541 				node->has_strong_ref = 0;
4542 			if (!weak && has_weak_ref)
4543 				node->has_weak_ref = 0;
4544 			if (!weak && !strong) {
4545 				binder_debug(BINDER_DEBUG_INTERNAL_REFS,
4546 					     "%d:%d node %d u%016llx c%016llx deleted\n",
4547 					     proc->pid, thread->pid,
4548 					     node_debug_id,
4549 					     (u64)node_ptr,
4550 					     (u64)node_cookie);
4551 				rb_erase(&node->rb_node, &proc->nodes);
4552 				binder_inner_proc_unlock(proc);
4553 				binder_node_lock(node);
4554 				/*
4555 				 * Acquire the node lock before freeing the
4556 				 * node to serialize with other threads that
4557 				 * may have been holding the node lock while
4558 				 * decrementing this node (avoids race where
4559 				 * this thread frees while the other thread
4560 				 * is unlocking the node after the final
4561 				 * decrement)
4562 				 */
4563 				binder_node_unlock(node);
4564 				binder_free_node(node);
4565 			} else
4566 				binder_inner_proc_unlock(proc);
4567 
4568 			if (weak && !has_weak_ref)
4569 				ret = binder_put_node_cmd(
4570 						proc, thread, &ptr, node_ptr,
4571 						node_cookie, node_debug_id,
4572 						BR_INCREFS, "BR_INCREFS");
4573 			if (!ret && strong && !has_strong_ref)
4574 				ret = binder_put_node_cmd(
4575 						proc, thread, &ptr, node_ptr,
4576 						node_cookie, node_debug_id,
4577 						BR_ACQUIRE, "BR_ACQUIRE");
4578 			if (!ret && !strong && has_strong_ref)
4579 				ret = binder_put_node_cmd(
4580 						proc, thread, &ptr, node_ptr,
4581 						node_cookie, node_debug_id,
4582 						BR_RELEASE, "BR_RELEASE");
4583 			if (!ret && !weak && has_weak_ref)
4584 				ret = binder_put_node_cmd(
4585 						proc, thread, &ptr, node_ptr,
4586 						node_cookie, node_debug_id,
4587 						BR_DECREFS, "BR_DECREFS");
4588 			if (orig_ptr == ptr)
4589 				binder_debug(BINDER_DEBUG_INTERNAL_REFS,
4590 					     "%d:%d node %d u%016llx c%016llx state unchanged\n",
4591 					     proc->pid, thread->pid,
4592 					     node_debug_id,
4593 					     (u64)node_ptr,
4594 					     (u64)node_cookie);
4595 			if (ret)
4596 				return ret;
4597 		} break;
4598 		case BINDER_WORK_DEAD_BINDER:
4599 		case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
4600 		case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
4601 			struct binder_ref_death *death;
4602 			uint32_t cmd;
4603 			binder_uintptr_t cookie;
4604 
4605 			death = container_of(w, struct binder_ref_death, work);
4606 			if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION)
4607 				cmd = BR_CLEAR_DEATH_NOTIFICATION_DONE;
4608 			else
4609 				cmd = BR_DEAD_BINDER;
4610 			cookie = death->cookie;
4611 
4612 			binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
4613 				     "%d:%d %s %016llx\n",
4614 				      proc->pid, thread->pid,
4615 				      cmd == BR_DEAD_BINDER ?
4616 				      "BR_DEAD_BINDER" :
4617 				      "BR_CLEAR_DEATH_NOTIFICATION_DONE",
4618 				      (u64)cookie);
4619 			if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) {
4620 				binder_inner_proc_unlock(proc);
4621 				kfree(death);
4622 				binder_stats_deleted(BINDER_STAT_DEATH);
4623 			} else {
4624 				binder_enqueue_work_ilocked(
4625 						w, &proc->delivered_death);
4626 				binder_inner_proc_unlock(proc);
4627 			}
4628 			if (put_user(cmd, (uint32_t __user *)ptr))
4629 				return -EFAULT;
4630 			ptr += sizeof(uint32_t);
4631 			if (put_user(cookie,
4632 				     (binder_uintptr_t __user *)ptr))
4633 				return -EFAULT;
4634 			ptr += sizeof(binder_uintptr_t);
4635 			binder_stat_br(proc, thread, cmd);
4636 			if (cmd == BR_DEAD_BINDER)
4637 				goto done; /* DEAD_BINDER notifications can cause transactions */
4638 		} break;
4639 		default:
4640 			binder_inner_proc_unlock(proc);
4641 			pr_err("%d:%d: bad work type %d\n",
4642 			       proc->pid, thread->pid, w->type);
4643 			break;
4644 		}
4645 
4646 		if (!t)
4647 			continue;
4648 
4649 		BUG_ON(t->buffer == NULL);
4650 		if (t->buffer->target_node) {
4651 			struct binder_node *target_node = t->buffer->target_node;
4652 
4653 			trd->target.ptr = target_node->ptr;
4654 			trd->cookie =  target_node->cookie;
4655 			t->saved_priority = task_nice(current);
4656 			if (t->priority < target_node->min_priority &&
4657 			    !(t->flags & TF_ONE_WAY))
4658 				binder_set_nice(t->priority);
4659 			else if (!(t->flags & TF_ONE_WAY) ||
4660 				 t->saved_priority > target_node->min_priority)
4661 				binder_set_nice(target_node->min_priority);
4662 			cmd = BR_TRANSACTION;
4663 		} else {
4664 			trd->target.ptr = 0;
4665 			trd->cookie = 0;
4666 			cmd = BR_REPLY;
4667 		}
4668 		trd->code = t->code;
4669 		trd->flags = t->flags;
4670 		trd->sender_euid = from_kuid(current_user_ns(), t->sender_euid);
4671 
4672 		t_from = binder_get_txn_from(t);
4673 		if (t_from) {
4674 			struct task_struct *sender = t_from->proc->tsk;
4675 
4676 			trd->sender_pid =
4677 				task_tgid_nr_ns(sender,
4678 						task_active_pid_ns(current));
4679 		} else {
4680 			trd->sender_pid = 0;
4681 		}
4682 
4683 		ret = binder_apply_fd_fixups(proc, t);
4684 		if (ret) {
4685 			struct binder_buffer *buffer = t->buffer;
4686 			bool oneway = !!(t->flags & TF_ONE_WAY);
4687 			int tid = t->debug_id;
4688 
4689 			if (t_from)
4690 				binder_thread_dec_tmpref(t_from);
4691 			buffer->transaction = NULL;
4692 			binder_cleanup_transaction(t, "fd fixups failed",
4693 						   BR_FAILED_REPLY);
4694 			binder_free_buf(proc, thread, buffer, true);
4695 			binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
4696 				     "%d:%d %stransaction %d fd fixups failed %d/%d, line %d\n",
4697 				     proc->pid, thread->pid,
4698 				     oneway ? "async " :
4699 					(cmd == BR_REPLY ? "reply " : ""),
4700 				     tid, BR_FAILED_REPLY, ret, __LINE__);
4701 			if (cmd == BR_REPLY) {
4702 				cmd = BR_FAILED_REPLY;
4703 				if (put_user(cmd, (uint32_t __user *)ptr))
4704 					return -EFAULT;
4705 				ptr += sizeof(uint32_t);
4706 				binder_stat_br(proc, thread, cmd);
4707 				break;
4708 			}
4709 			continue;
4710 		}
4711 		trd->data_size = t->buffer->data_size;
4712 		trd->offsets_size = t->buffer->offsets_size;
4713 		trd->data.ptr.buffer = (uintptr_t)t->buffer->user_data;
4714 		trd->data.ptr.offsets = trd->data.ptr.buffer +
4715 					ALIGN(t->buffer->data_size,
4716 					    sizeof(void *));
4717 
4718 		tr.secctx = t->security_ctx;
4719 		if (t->security_ctx) {
4720 			cmd = BR_TRANSACTION_SEC_CTX;
4721 			trsize = sizeof(tr);
4722 		}
4723 		if (put_user(cmd, (uint32_t __user *)ptr)) {
4724 			if (t_from)
4725 				binder_thread_dec_tmpref(t_from);
4726 
4727 			binder_cleanup_transaction(t, "put_user failed",
4728 						   BR_FAILED_REPLY);
4729 
4730 			return -EFAULT;
4731 		}
4732 		ptr += sizeof(uint32_t);
4733 		if (copy_to_user(ptr, &tr, trsize)) {
4734 			if (t_from)
4735 				binder_thread_dec_tmpref(t_from);
4736 
4737 			binder_cleanup_transaction(t, "copy_to_user failed",
4738 						   BR_FAILED_REPLY);
4739 
4740 			return -EFAULT;
4741 		}
4742 		ptr += trsize;
4743 
4744 		trace_binder_transaction_received(t);
4745 		binder_stat_br(proc, thread, cmd);
4746 		binder_debug(BINDER_DEBUG_TRANSACTION,
4747 			     "%d:%d %s %d %d:%d, cmd %u size %zd-%zd ptr %016llx-%016llx\n",
4748 			     proc->pid, thread->pid,
4749 			     (cmd == BR_TRANSACTION) ? "BR_TRANSACTION" :
4750 				(cmd == BR_TRANSACTION_SEC_CTX) ?
4751 				     "BR_TRANSACTION_SEC_CTX" : "BR_REPLY",
4752 			     t->debug_id, t_from ? t_from->proc->pid : 0,
4753 			     t_from ? t_from->pid : 0, cmd,
4754 			     t->buffer->data_size, t->buffer->offsets_size,
4755 			     (u64)trd->data.ptr.buffer,
4756 			     (u64)trd->data.ptr.offsets);
4757 
4758 		if (t_from)
4759 			binder_thread_dec_tmpref(t_from);
4760 		t->buffer->allow_user_free = 1;
4761 		if (cmd != BR_REPLY && !(t->flags & TF_ONE_WAY)) {
4762 			binder_inner_proc_lock(thread->proc);
4763 			t->to_parent = thread->transaction_stack;
4764 			t->to_thread = thread;
4765 			thread->transaction_stack = t;
4766 			binder_inner_proc_unlock(thread->proc);
4767 		} else {
4768 			binder_free_transaction(t);
4769 		}
4770 		break;
4771 	}
4772 
4773 done:
4774 
4775 	*consumed = ptr - buffer;
4776 	binder_inner_proc_lock(proc);
4777 	if (proc->requested_threads == 0 &&
4778 	    list_empty(&thread->proc->waiting_threads) &&
4779 	    proc->requested_threads_started < proc->max_threads &&
4780 	    (thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
4781 	     BINDER_LOOPER_STATE_ENTERED)) /* the user-space code fails to */
4782 	     /*spawn a new thread if we leave this out */) {
4783 		proc->requested_threads++;
4784 		binder_inner_proc_unlock(proc);
4785 		binder_debug(BINDER_DEBUG_THREADS,
4786 			     "%d:%d BR_SPAWN_LOOPER\n",
4787 			     proc->pid, thread->pid);
4788 		if (put_user(BR_SPAWN_LOOPER, (uint32_t __user *)buffer))
4789 			return -EFAULT;
4790 		binder_stat_br(proc, thread, BR_SPAWN_LOOPER);
4791 	} else
4792 		binder_inner_proc_unlock(proc);
4793 	return 0;
4794 }
4795 
binder_release_work(struct binder_proc * proc,struct list_head * list)4796 static void binder_release_work(struct binder_proc *proc,
4797 				struct list_head *list)
4798 {
4799 	struct binder_work *w;
4800 	enum binder_work_type wtype;
4801 
4802 	while (1) {
4803 		binder_inner_proc_lock(proc);
4804 		w = binder_dequeue_work_head_ilocked(list);
4805 		wtype = w ? w->type : 0;
4806 		binder_inner_proc_unlock(proc);
4807 		if (!w)
4808 			return;
4809 
4810 		switch (wtype) {
4811 		case BINDER_WORK_TRANSACTION: {
4812 			struct binder_transaction *t;
4813 
4814 			t = container_of(w, struct binder_transaction, work);
4815 
4816 			binder_cleanup_transaction(t, "process died.",
4817 						   BR_DEAD_REPLY);
4818 		} break;
4819 		case BINDER_WORK_RETURN_ERROR: {
4820 			struct binder_error *e = container_of(
4821 					w, struct binder_error, work);
4822 
4823 			binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
4824 				"undelivered TRANSACTION_ERROR: %u\n",
4825 				e->cmd);
4826 		} break;
4827 		case BINDER_WORK_TRANSACTION_PENDING:
4828 		case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT:
4829 		case BINDER_WORK_TRANSACTION_COMPLETE: {
4830 			binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
4831 				"undelivered TRANSACTION_COMPLETE\n");
4832 			kfree(w);
4833 			binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
4834 		} break;
4835 		case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
4836 		case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
4837 			struct binder_ref_death *death;
4838 
4839 			death = container_of(w, struct binder_ref_death, work);
4840 			binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
4841 				"undelivered death notification, %016llx\n",
4842 				(u64)death->cookie);
4843 			kfree(death);
4844 			binder_stats_deleted(BINDER_STAT_DEATH);
4845 		} break;
4846 		case BINDER_WORK_NODE:
4847 			break;
4848 		default:
4849 			pr_err("unexpected work type, %d, not freed\n",
4850 			       wtype);
4851 			break;
4852 		}
4853 	}
4854 
4855 }
4856 
binder_get_thread_ilocked(struct binder_proc * proc,struct binder_thread * new_thread)4857 static struct binder_thread *binder_get_thread_ilocked(
4858 		struct binder_proc *proc, struct binder_thread *new_thread)
4859 {
4860 	struct binder_thread *thread = NULL;
4861 	struct rb_node *parent = NULL;
4862 	struct rb_node **p = &proc->threads.rb_node;
4863 
4864 	while (*p) {
4865 		parent = *p;
4866 		thread = rb_entry(parent, struct binder_thread, rb_node);
4867 
4868 		if (current->pid < thread->pid)
4869 			p = &(*p)->rb_left;
4870 		else if (current->pid > thread->pid)
4871 			p = &(*p)->rb_right;
4872 		else
4873 			return thread;
4874 	}
4875 	if (!new_thread)
4876 		return NULL;
4877 	thread = new_thread;
4878 	binder_stats_created(BINDER_STAT_THREAD);
4879 	thread->proc = proc;
4880 	thread->pid = current->pid;
4881 	atomic_set(&thread->tmp_ref, 0);
4882 	init_waitqueue_head(&thread->wait);
4883 	INIT_LIST_HEAD(&thread->todo);
4884 	rb_link_node(&thread->rb_node, parent, p);
4885 	rb_insert_color(&thread->rb_node, &proc->threads);
4886 	thread->looper_need_return = true;
4887 	thread->return_error.work.type = BINDER_WORK_RETURN_ERROR;
4888 	thread->return_error.cmd = BR_OK;
4889 	thread->reply_error.work.type = BINDER_WORK_RETURN_ERROR;
4890 	thread->reply_error.cmd = BR_OK;
4891 	thread->ee.command = BR_OK;
4892 	INIT_LIST_HEAD(&new_thread->waiting_thread_node);
4893 	return thread;
4894 }
4895 
binder_get_thread(struct binder_proc * proc)4896 static struct binder_thread *binder_get_thread(struct binder_proc *proc)
4897 {
4898 	struct binder_thread *thread;
4899 	struct binder_thread *new_thread;
4900 
4901 	binder_inner_proc_lock(proc);
4902 	thread = binder_get_thread_ilocked(proc, NULL);
4903 	binder_inner_proc_unlock(proc);
4904 	if (!thread) {
4905 		new_thread = kzalloc(sizeof(*thread), GFP_KERNEL);
4906 		if (new_thread == NULL)
4907 			return NULL;
4908 		binder_inner_proc_lock(proc);
4909 		thread = binder_get_thread_ilocked(proc, new_thread);
4910 		binder_inner_proc_unlock(proc);
4911 		if (thread != new_thread)
4912 			kfree(new_thread);
4913 	}
4914 	return thread;
4915 }
4916 
binder_free_proc(struct binder_proc * proc)4917 static void binder_free_proc(struct binder_proc *proc)
4918 {
4919 	struct binder_device *device;
4920 
4921 	BUG_ON(!list_empty(&proc->todo));
4922 	BUG_ON(!list_empty(&proc->delivered_death));
4923 	if (proc->outstanding_txns)
4924 		pr_warn("%s: Unexpected outstanding_txns %d\n",
4925 			__func__, proc->outstanding_txns);
4926 	device = container_of(proc->context, struct binder_device, context);
4927 	if (refcount_dec_and_test(&device->ref)) {
4928 		kfree(proc->context->name);
4929 		kfree(device);
4930 	}
4931 	binder_alloc_deferred_release(&proc->alloc);
4932 	put_task_struct(proc->tsk);
4933 	put_cred(proc->cred);
4934 	binder_stats_deleted(BINDER_STAT_PROC);
4935 	kfree(proc);
4936 }
4937 
binder_free_thread(struct binder_thread * thread)4938 static void binder_free_thread(struct binder_thread *thread)
4939 {
4940 	BUG_ON(!list_empty(&thread->todo));
4941 	binder_stats_deleted(BINDER_STAT_THREAD);
4942 	binder_proc_dec_tmpref(thread->proc);
4943 	kfree(thread);
4944 }
4945 
binder_thread_release(struct binder_proc * proc,struct binder_thread * thread)4946 static int binder_thread_release(struct binder_proc *proc,
4947 				 struct binder_thread *thread)
4948 {
4949 	struct binder_transaction *t;
4950 	struct binder_transaction *send_reply = NULL;
4951 	int active_transactions = 0;
4952 	struct binder_transaction *last_t = NULL;
4953 
4954 	binder_inner_proc_lock(thread->proc);
4955 	/*
4956 	 * take a ref on the proc so it survives
4957 	 * after we remove this thread from proc->threads.
4958 	 * The corresponding dec is when we actually
4959 	 * free the thread in binder_free_thread()
4960 	 */
4961 	proc->tmp_ref++;
4962 	/*
4963 	 * take a ref on this thread to ensure it
4964 	 * survives while we are releasing it
4965 	 */
4966 	atomic_inc(&thread->tmp_ref);
4967 	rb_erase(&thread->rb_node, &proc->threads);
4968 	t = thread->transaction_stack;
4969 	if (t) {
4970 		spin_lock(&t->lock);
4971 		if (t->to_thread == thread)
4972 			send_reply = t;
4973 	} else {
4974 		__acquire(&t->lock);
4975 	}
4976 	thread->is_dead = true;
4977 
4978 	while (t) {
4979 		last_t = t;
4980 		active_transactions++;
4981 		binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
4982 			     "release %d:%d transaction %d %s, still active\n",
4983 			      proc->pid, thread->pid,
4984 			     t->debug_id,
4985 			     (t->to_thread == thread) ? "in" : "out");
4986 
4987 		if (t->to_thread == thread) {
4988 			thread->proc->outstanding_txns--;
4989 			t->to_proc = NULL;
4990 			t->to_thread = NULL;
4991 			if (t->buffer) {
4992 				t->buffer->transaction = NULL;
4993 				t->buffer = NULL;
4994 			}
4995 			t = t->to_parent;
4996 		} else if (t->from == thread) {
4997 			t->from = NULL;
4998 			t = t->from_parent;
4999 		} else
5000 			BUG();
5001 		spin_unlock(&last_t->lock);
5002 		if (t)
5003 			spin_lock(&t->lock);
5004 		else
5005 			__acquire(&t->lock);
5006 	}
5007 	/* annotation for sparse, lock not acquired in last iteration above */
5008 	__release(&t->lock);
5009 
5010 	/*
5011 	 * If this thread used poll, make sure we remove the waitqueue from any
5012 	 * poll data structures holding it.
5013 	 */
5014 	if (thread->looper & BINDER_LOOPER_STATE_POLL)
5015 		wake_up_pollfree(&thread->wait);
5016 
5017 	binder_inner_proc_unlock(thread->proc);
5018 
5019 	/*
5020 	 * This is needed to avoid races between wake_up_pollfree() above and
5021 	 * someone else removing the last entry from the queue for other reasons
5022 	 * (e.g. ep_remove_wait_queue() being called due to an epoll file
5023 	 * descriptor being closed).  Such other users hold an RCU read lock, so
5024 	 * we can be sure they're done after we call synchronize_rcu().
5025 	 */
5026 	if (thread->looper & BINDER_LOOPER_STATE_POLL)
5027 		synchronize_rcu();
5028 
5029 	if (send_reply)
5030 		binder_send_failed_reply(send_reply, BR_DEAD_REPLY);
5031 	binder_release_work(proc, &thread->todo);
5032 	binder_thread_dec_tmpref(thread);
5033 	return active_transactions;
5034 }
5035 
binder_poll(struct file * filp,struct poll_table_struct * wait)5036 static __poll_t binder_poll(struct file *filp,
5037 				struct poll_table_struct *wait)
5038 {
5039 	struct binder_proc *proc = filp->private_data;
5040 	struct binder_thread *thread = NULL;
5041 	bool wait_for_proc_work;
5042 
5043 	thread = binder_get_thread(proc);
5044 	if (!thread)
5045 		return EPOLLERR;
5046 
5047 	binder_inner_proc_lock(thread->proc);
5048 	thread->looper |= BINDER_LOOPER_STATE_POLL;
5049 	wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
5050 
5051 	binder_inner_proc_unlock(thread->proc);
5052 
5053 	poll_wait(filp, &thread->wait, wait);
5054 
5055 	if (binder_has_work(thread, wait_for_proc_work))
5056 		return EPOLLIN;
5057 
5058 	return 0;
5059 }
5060 
binder_ioctl_write_read(struct file * filp,unsigned long arg,struct binder_thread * thread)5061 static int binder_ioctl_write_read(struct file *filp, unsigned long arg,
5062 				struct binder_thread *thread)
5063 {
5064 	int ret = 0;
5065 	struct binder_proc *proc = filp->private_data;
5066 	void __user *ubuf = (void __user *)arg;
5067 	struct binder_write_read bwr;
5068 
5069 	if (copy_from_user(&bwr, ubuf, sizeof(bwr))) {
5070 		ret = -EFAULT;
5071 		goto out;
5072 	}
5073 	binder_debug(BINDER_DEBUG_READ_WRITE,
5074 		     "%d:%d write %lld at %016llx, read %lld at %016llx\n",
5075 		     proc->pid, thread->pid,
5076 		     (u64)bwr.write_size, (u64)bwr.write_buffer,
5077 		     (u64)bwr.read_size, (u64)bwr.read_buffer);
5078 
5079 	if (bwr.write_size > 0) {
5080 		ret = binder_thread_write(proc, thread,
5081 					  bwr.write_buffer,
5082 					  bwr.write_size,
5083 					  &bwr.write_consumed);
5084 		trace_binder_write_done(ret);
5085 		if (ret < 0) {
5086 			bwr.read_consumed = 0;
5087 			if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
5088 				ret = -EFAULT;
5089 			goto out;
5090 		}
5091 	}
5092 	if (bwr.read_size > 0) {
5093 		ret = binder_thread_read(proc, thread, bwr.read_buffer,
5094 					 bwr.read_size,
5095 					 &bwr.read_consumed,
5096 					 filp->f_flags & O_NONBLOCK);
5097 		trace_binder_read_done(ret);
5098 		binder_inner_proc_lock(proc);
5099 		if (!binder_worklist_empty_ilocked(&proc->todo))
5100 			binder_wakeup_proc_ilocked(proc);
5101 		binder_inner_proc_unlock(proc);
5102 		if (ret < 0) {
5103 			if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
5104 				ret = -EFAULT;
5105 			goto out;
5106 		}
5107 	}
5108 	binder_debug(BINDER_DEBUG_READ_WRITE,
5109 		     "%d:%d wrote %lld of %lld, read return %lld of %lld\n",
5110 		     proc->pid, thread->pid,
5111 		     (u64)bwr.write_consumed, (u64)bwr.write_size,
5112 		     (u64)bwr.read_consumed, (u64)bwr.read_size);
5113 	if (copy_to_user(ubuf, &bwr, sizeof(bwr))) {
5114 		ret = -EFAULT;
5115 		goto out;
5116 	}
5117 out:
5118 	return ret;
5119 }
5120 
binder_ioctl_set_ctx_mgr(struct file * filp,struct flat_binder_object * fbo)5121 static int binder_ioctl_set_ctx_mgr(struct file *filp,
5122 				    struct flat_binder_object *fbo)
5123 {
5124 	int ret = 0;
5125 	struct binder_proc *proc = filp->private_data;
5126 	struct binder_context *context = proc->context;
5127 	struct binder_node *new_node;
5128 	kuid_t curr_euid = current_euid();
5129 
5130 	mutex_lock(&context->context_mgr_node_lock);
5131 	if (context->binder_context_mgr_node) {
5132 		pr_err("BINDER_SET_CONTEXT_MGR already set\n");
5133 		ret = -EBUSY;
5134 		goto out;
5135 	}
5136 	ret = security_binder_set_context_mgr(proc->cred);
5137 	if (ret < 0)
5138 		goto out;
5139 	if (uid_valid(context->binder_context_mgr_uid)) {
5140 		if (!uid_eq(context->binder_context_mgr_uid, curr_euid)) {
5141 			pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n",
5142 			       from_kuid(&init_user_ns, curr_euid),
5143 			       from_kuid(&init_user_ns,
5144 					 context->binder_context_mgr_uid));
5145 			ret = -EPERM;
5146 			goto out;
5147 		}
5148 	} else {
5149 		context->binder_context_mgr_uid = curr_euid;
5150 	}
5151 	new_node = binder_new_node(proc, fbo);
5152 	if (!new_node) {
5153 		ret = -ENOMEM;
5154 		goto out;
5155 	}
5156 	binder_node_lock(new_node);
5157 	new_node->local_weak_refs++;
5158 	new_node->local_strong_refs++;
5159 	new_node->has_strong_ref = 1;
5160 	new_node->has_weak_ref = 1;
5161 	context->binder_context_mgr_node = new_node;
5162 	binder_node_unlock(new_node);
5163 	binder_put_node(new_node);
5164 out:
5165 	mutex_unlock(&context->context_mgr_node_lock);
5166 	return ret;
5167 }
5168 
binder_ioctl_get_node_info_for_ref(struct binder_proc * proc,struct binder_node_info_for_ref * info)5169 static int binder_ioctl_get_node_info_for_ref(struct binder_proc *proc,
5170 		struct binder_node_info_for_ref *info)
5171 {
5172 	struct binder_node *node;
5173 	struct binder_context *context = proc->context;
5174 	__u32 handle = info->handle;
5175 
5176 	if (info->strong_count || info->weak_count || info->reserved1 ||
5177 	    info->reserved2 || info->reserved3) {
5178 		binder_user_error("%d BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero.",
5179 				  proc->pid);
5180 		return -EINVAL;
5181 	}
5182 
5183 	/* This ioctl may only be used by the context manager */
5184 	mutex_lock(&context->context_mgr_node_lock);
5185 	if (!context->binder_context_mgr_node ||
5186 		context->binder_context_mgr_node->proc != proc) {
5187 		mutex_unlock(&context->context_mgr_node_lock);
5188 		return -EPERM;
5189 	}
5190 	mutex_unlock(&context->context_mgr_node_lock);
5191 
5192 	node = binder_get_node_from_ref(proc, handle, true, NULL);
5193 	if (!node)
5194 		return -EINVAL;
5195 
5196 	info->strong_count = node->local_strong_refs +
5197 		node->internal_strong_refs;
5198 	info->weak_count = node->local_weak_refs;
5199 
5200 	binder_put_node(node);
5201 
5202 	return 0;
5203 }
5204 
binder_ioctl_get_node_debug_info(struct binder_proc * proc,struct binder_node_debug_info * info)5205 static int binder_ioctl_get_node_debug_info(struct binder_proc *proc,
5206 				struct binder_node_debug_info *info)
5207 {
5208 	struct rb_node *n;
5209 	binder_uintptr_t ptr = info->ptr;
5210 
5211 	memset(info, 0, sizeof(*info));
5212 
5213 	binder_inner_proc_lock(proc);
5214 	for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) {
5215 		struct binder_node *node = rb_entry(n, struct binder_node,
5216 						    rb_node);
5217 		if (node->ptr > ptr) {
5218 			info->ptr = node->ptr;
5219 			info->cookie = node->cookie;
5220 			info->has_strong_ref = node->has_strong_ref;
5221 			info->has_weak_ref = node->has_weak_ref;
5222 			break;
5223 		}
5224 	}
5225 	binder_inner_proc_unlock(proc);
5226 
5227 	return 0;
5228 }
5229 
binder_txns_pending_ilocked(struct binder_proc * proc)5230 static bool binder_txns_pending_ilocked(struct binder_proc *proc)
5231 {
5232 	struct rb_node *n;
5233 	struct binder_thread *thread;
5234 
5235 	if (proc->outstanding_txns > 0)
5236 		return true;
5237 
5238 	for (n = rb_first(&proc->threads); n; n = rb_next(n)) {
5239 		thread = rb_entry(n, struct binder_thread, rb_node);
5240 		if (thread->transaction_stack)
5241 			return true;
5242 	}
5243 	return false;
5244 }
5245 
binder_ioctl_freeze(struct binder_freeze_info * info,struct binder_proc * target_proc)5246 static int binder_ioctl_freeze(struct binder_freeze_info *info,
5247 			       struct binder_proc *target_proc)
5248 {
5249 	int ret = 0;
5250 
5251 	if (!info->enable) {
5252 		binder_inner_proc_lock(target_proc);
5253 		target_proc->sync_recv = false;
5254 		target_proc->async_recv = false;
5255 		target_proc->is_frozen = false;
5256 		binder_inner_proc_unlock(target_proc);
5257 		return 0;
5258 	}
5259 
5260 	/*
5261 	 * Freezing the target. Prevent new transactions by
5262 	 * setting frozen state. If timeout specified, wait
5263 	 * for transactions to drain.
5264 	 */
5265 	binder_inner_proc_lock(target_proc);
5266 	target_proc->sync_recv = false;
5267 	target_proc->async_recv = false;
5268 	target_proc->is_frozen = true;
5269 	binder_inner_proc_unlock(target_proc);
5270 
5271 	if (info->timeout_ms > 0)
5272 		ret = wait_event_interruptible_timeout(
5273 			target_proc->freeze_wait,
5274 			(!target_proc->outstanding_txns),
5275 			msecs_to_jiffies(info->timeout_ms));
5276 
5277 	/* Check pending transactions that wait for reply */
5278 	if (ret >= 0) {
5279 		binder_inner_proc_lock(target_proc);
5280 		if (binder_txns_pending_ilocked(target_proc))
5281 			ret = -EAGAIN;
5282 		binder_inner_proc_unlock(target_proc);
5283 	}
5284 
5285 	if (ret < 0) {
5286 		binder_inner_proc_lock(target_proc);
5287 		target_proc->is_frozen = false;
5288 		binder_inner_proc_unlock(target_proc);
5289 	}
5290 
5291 	return ret;
5292 }
5293 
binder_ioctl_get_freezer_info(struct binder_frozen_status_info * info)5294 static int binder_ioctl_get_freezer_info(
5295 				struct binder_frozen_status_info *info)
5296 {
5297 	struct binder_proc *target_proc;
5298 	bool found = false;
5299 	__u32 txns_pending;
5300 
5301 	info->sync_recv = 0;
5302 	info->async_recv = 0;
5303 
5304 	mutex_lock(&binder_procs_lock);
5305 	hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
5306 		if (target_proc->pid == info->pid) {
5307 			found = true;
5308 			binder_inner_proc_lock(target_proc);
5309 			txns_pending = binder_txns_pending_ilocked(target_proc);
5310 			info->sync_recv |= target_proc->sync_recv |
5311 					(txns_pending << 1);
5312 			info->async_recv |= target_proc->async_recv;
5313 			binder_inner_proc_unlock(target_proc);
5314 		}
5315 	}
5316 	mutex_unlock(&binder_procs_lock);
5317 
5318 	if (!found)
5319 		return -EINVAL;
5320 
5321 	return 0;
5322 }
5323 
binder_ioctl_get_extended_error(struct binder_thread * thread,void __user * ubuf)5324 static int binder_ioctl_get_extended_error(struct binder_thread *thread,
5325 					   void __user *ubuf)
5326 {
5327 	struct binder_extended_error ee;
5328 
5329 	binder_inner_proc_lock(thread->proc);
5330 	ee = thread->ee;
5331 	binder_set_extended_error(&thread->ee, 0, BR_OK, 0);
5332 	binder_inner_proc_unlock(thread->proc);
5333 
5334 	if (copy_to_user(ubuf, &ee, sizeof(ee)))
5335 		return -EFAULT;
5336 
5337 	return 0;
5338 }
5339 
binder_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)5340 static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
5341 {
5342 	int ret;
5343 	struct binder_proc *proc = filp->private_data;
5344 	struct binder_thread *thread;
5345 	void __user *ubuf = (void __user *)arg;
5346 
5347 	/*pr_info("binder_ioctl: %d:%d %x %lx\n",
5348 			proc->pid, current->pid, cmd, arg);*/
5349 
5350 	binder_selftest_alloc(&proc->alloc);
5351 
5352 	trace_binder_ioctl(cmd, arg);
5353 
5354 	ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
5355 	if (ret)
5356 		goto err_unlocked;
5357 
5358 	thread = binder_get_thread(proc);
5359 	if (thread == NULL) {
5360 		ret = -ENOMEM;
5361 		goto err;
5362 	}
5363 
5364 	switch (cmd) {
5365 	case BINDER_WRITE_READ:
5366 		ret = binder_ioctl_write_read(filp, arg, thread);
5367 		if (ret)
5368 			goto err;
5369 		break;
5370 	case BINDER_SET_MAX_THREADS: {
5371 		u32 max_threads;
5372 
5373 		if (copy_from_user(&max_threads, ubuf,
5374 				   sizeof(max_threads))) {
5375 			ret = -EINVAL;
5376 			goto err;
5377 		}
5378 		binder_inner_proc_lock(proc);
5379 		proc->max_threads = max_threads;
5380 		binder_inner_proc_unlock(proc);
5381 		break;
5382 	}
5383 	case BINDER_SET_CONTEXT_MGR_EXT: {
5384 		struct flat_binder_object fbo;
5385 
5386 		if (copy_from_user(&fbo, ubuf, sizeof(fbo))) {
5387 			ret = -EINVAL;
5388 			goto err;
5389 		}
5390 		ret = binder_ioctl_set_ctx_mgr(filp, &fbo);
5391 		if (ret)
5392 			goto err;
5393 		break;
5394 	}
5395 	case BINDER_SET_CONTEXT_MGR:
5396 		ret = binder_ioctl_set_ctx_mgr(filp, NULL);
5397 		if (ret)
5398 			goto err;
5399 		break;
5400 	case BINDER_THREAD_EXIT:
5401 		binder_debug(BINDER_DEBUG_THREADS, "%d:%d exit\n",
5402 			     proc->pid, thread->pid);
5403 		binder_thread_release(proc, thread);
5404 		thread = NULL;
5405 		break;
5406 	case BINDER_VERSION: {
5407 		struct binder_version __user *ver = ubuf;
5408 
5409 		if (put_user(BINDER_CURRENT_PROTOCOL_VERSION,
5410 			     &ver->protocol_version)) {
5411 			ret = -EINVAL;
5412 			goto err;
5413 		}
5414 		break;
5415 	}
5416 	case BINDER_GET_NODE_INFO_FOR_REF: {
5417 		struct binder_node_info_for_ref info;
5418 
5419 		if (copy_from_user(&info, ubuf, sizeof(info))) {
5420 			ret = -EFAULT;
5421 			goto err;
5422 		}
5423 
5424 		ret = binder_ioctl_get_node_info_for_ref(proc, &info);
5425 		if (ret < 0)
5426 			goto err;
5427 
5428 		if (copy_to_user(ubuf, &info, sizeof(info))) {
5429 			ret = -EFAULT;
5430 			goto err;
5431 		}
5432 
5433 		break;
5434 	}
5435 	case BINDER_GET_NODE_DEBUG_INFO: {
5436 		struct binder_node_debug_info info;
5437 
5438 		if (copy_from_user(&info, ubuf, sizeof(info))) {
5439 			ret = -EFAULT;
5440 			goto err;
5441 		}
5442 
5443 		ret = binder_ioctl_get_node_debug_info(proc, &info);
5444 		if (ret < 0)
5445 			goto err;
5446 
5447 		if (copy_to_user(ubuf, &info, sizeof(info))) {
5448 			ret = -EFAULT;
5449 			goto err;
5450 		}
5451 		break;
5452 	}
5453 	case BINDER_FREEZE: {
5454 		struct binder_freeze_info info;
5455 		struct binder_proc **target_procs = NULL, *target_proc;
5456 		int target_procs_count = 0, i = 0;
5457 
5458 		ret = 0;
5459 
5460 		if (copy_from_user(&info, ubuf, sizeof(info))) {
5461 			ret = -EFAULT;
5462 			goto err;
5463 		}
5464 
5465 		mutex_lock(&binder_procs_lock);
5466 		hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
5467 			if (target_proc->pid == info.pid)
5468 				target_procs_count++;
5469 		}
5470 
5471 		if (target_procs_count == 0) {
5472 			mutex_unlock(&binder_procs_lock);
5473 			ret = -EINVAL;
5474 			goto err;
5475 		}
5476 
5477 		target_procs = kcalloc(target_procs_count,
5478 				       sizeof(struct binder_proc *),
5479 				       GFP_KERNEL);
5480 
5481 		if (!target_procs) {
5482 			mutex_unlock(&binder_procs_lock);
5483 			ret = -ENOMEM;
5484 			goto err;
5485 		}
5486 
5487 		hlist_for_each_entry(target_proc, &binder_procs, proc_node) {
5488 			if (target_proc->pid != info.pid)
5489 				continue;
5490 
5491 			binder_inner_proc_lock(target_proc);
5492 			target_proc->tmp_ref++;
5493 			binder_inner_proc_unlock(target_proc);
5494 
5495 			target_procs[i++] = target_proc;
5496 		}
5497 		mutex_unlock(&binder_procs_lock);
5498 
5499 		for (i = 0; i < target_procs_count; i++) {
5500 			if (ret >= 0)
5501 				ret = binder_ioctl_freeze(&info,
5502 							  target_procs[i]);
5503 
5504 			binder_proc_dec_tmpref(target_procs[i]);
5505 		}
5506 
5507 		kfree(target_procs);
5508 
5509 		if (ret < 0)
5510 			goto err;
5511 		break;
5512 	}
5513 	case BINDER_GET_FROZEN_INFO: {
5514 		struct binder_frozen_status_info info;
5515 
5516 		if (copy_from_user(&info, ubuf, sizeof(info))) {
5517 			ret = -EFAULT;
5518 			goto err;
5519 		}
5520 
5521 		ret = binder_ioctl_get_freezer_info(&info);
5522 		if (ret < 0)
5523 			goto err;
5524 
5525 		if (copy_to_user(ubuf, &info, sizeof(info))) {
5526 			ret = -EFAULT;
5527 			goto err;
5528 		}
5529 		break;
5530 	}
5531 	case BINDER_ENABLE_ONEWAY_SPAM_DETECTION: {
5532 		uint32_t enable;
5533 
5534 		if (copy_from_user(&enable, ubuf, sizeof(enable))) {
5535 			ret = -EFAULT;
5536 			goto err;
5537 		}
5538 		binder_inner_proc_lock(proc);
5539 		proc->oneway_spam_detection_enabled = (bool)enable;
5540 		binder_inner_proc_unlock(proc);
5541 		break;
5542 	}
5543 	case BINDER_GET_EXTENDED_ERROR:
5544 		ret = binder_ioctl_get_extended_error(thread, ubuf);
5545 		if (ret < 0)
5546 			goto err;
5547 		break;
5548 	default:
5549 		ret = -EINVAL;
5550 		goto err;
5551 	}
5552 	ret = 0;
5553 err:
5554 	if (thread)
5555 		thread->looper_need_return = false;
5556 	wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
5557 	if (ret && ret != -EINTR)
5558 		pr_info("%d:%d ioctl %x %lx returned %d\n", proc->pid, current->pid, cmd, arg, ret);
5559 err_unlocked:
5560 	trace_binder_ioctl_done(ret);
5561 	return ret;
5562 }
5563 
binder_vma_open(struct vm_area_struct * vma)5564 static void binder_vma_open(struct vm_area_struct *vma)
5565 {
5566 	struct binder_proc *proc = vma->vm_private_data;
5567 
5568 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5569 		     "%d open vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
5570 		     proc->pid, vma->vm_start, vma->vm_end,
5571 		     (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
5572 		     (unsigned long)pgprot_val(vma->vm_page_prot));
5573 }
5574 
binder_vma_close(struct vm_area_struct * vma)5575 static void binder_vma_close(struct vm_area_struct *vma)
5576 {
5577 	struct binder_proc *proc = vma->vm_private_data;
5578 
5579 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5580 		     "%d close vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
5581 		     proc->pid, vma->vm_start, vma->vm_end,
5582 		     (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
5583 		     (unsigned long)pgprot_val(vma->vm_page_prot));
5584 	binder_alloc_vma_close(&proc->alloc);
5585 }
5586 
binder_vm_fault(struct vm_fault * vmf)5587 static vm_fault_t binder_vm_fault(struct vm_fault *vmf)
5588 {
5589 	return VM_FAULT_SIGBUS;
5590 }
5591 
5592 static const struct vm_operations_struct binder_vm_ops = {
5593 	.open = binder_vma_open,
5594 	.close = binder_vma_close,
5595 	.fault = binder_vm_fault,
5596 };
5597 
binder_mmap(struct file * filp,struct vm_area_struct * vma)5598 static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
5599 {
5600 	struct binder_proc *proc = filp->private_data;
5601 
5602 	if (proc->tsk != current->group_leader)
5603 		return -EINVAL;
5604 
5605 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5606 		     "%s: %d %lx-%lx (%ld K) vma %lx pagep %lx\n",
5607 		     __func__, proc->pid, vma->vm_start, vma->vm_end,
5608 		     (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
5609 		     (unsigned long)pgprot_val(vma->vm_page_prot));
5610 
5611 	if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
5612 		pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
5613 		       proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM);
5614 		return -EPERM;
5615 	}
5616 	vm_flags_mod(vma, VM_DONTCOPY | VM_MIXEDMAP, VM_MAYWRITE);
5617 
5618 	vma->vm_ops = &binder_vm_ops;
5619 	vma->vm_private_data = proc;
5620 
5621 	return binder_alloc_mmap_handler(&proc->alloc, vma);
5622 }
5623 
binder_open(struct inode * nodp,struct file * filp)5624 static int binder_open(struct inode *nodp, struct file *filp)
5625 {
5626 	struct binder_proc *proc, *itr;
5627 	struct binder_device *binder_dev;
5628 	struct binderfs_info *info;
5629 	struct dentry *binder_binderfs_dir_entry_proc = NULL;
5630 	bool existing_pid = false;
5631 
5632 	binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__,
5633 		     current->group_leader->pid, current->pid);
5634 
5635 	proc = kzalloc(sizeof(*proc), GFP_KERNEL);
5636 	if (proc == NULL)
5637 		return -ENOMEM;
5638 	spin_lock_init(&proc->inner_lock);
5639 	spin_lock_init(&proc->outer_lock);
5640 	get_task_struct(current->group_leader);
5641 	proc->tsk = current->group_leader;
5642 	proc->cred = get_cred(filp->f_cred);
5643 	INIT_LIST_HEAD(&proc->todo);
5644 	init_waitqueue_head(&proc->freeze_wait);
5645 	proc->default_priority = task_nice(current);
5646 	/* binderfs stashes devices in i_private */
5647 	if (is_binderfs_device(nodp)) {
5648 		binder_dev = nodp->i_private;
5649 		info = nodp->i_sb->s_fs_info;
5650 		binder_binderfs_dir_entry_proc = info->proc_log_dir;
5651 	} else {
5652 		binder_dev = container_of(filp->private_data,
5653 					  struct binder_device, miscdev);
5654 	}
5655 	refcount_inc(&binder_dev->ref);
5656 	proc->context = &binder_dev->context;
5657 	binder_alloc_init(&proc->alloc);
5658 
5659 	binder_stats_created(BINDER_STAT_PROC);
5660 	proc->pid = current->group_leader->pid;
5661 	INIT_LIST_HEAD(&proc->delivered_death);
5662 	INIT_LIST_HEAD(&proc->waiting_threads);
5663 	filp->private_data = proc;
5664 
5665 	mutex_lock(&binder_procs_lock);
5666 	hlist_for_each_entry(itr, &binder_procs, proc_node) {
5667 		if (itr->pid == proc->pid) {
5668 			existing_pid = true;
5669 			break;
5670 		}
5671 	}
5672 	hlist_add_head(&proc->proc_node, &binder_procs);
5673 	mutex_unlock(&binder_procs_lock);
5674 
5675 	if (binder_debugfs_dir_entry_proc && !existing_pid) {
5676 		char strbuf[11];
5677 
5678 		snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
5679 		/*
5680 		 * proc debug entries are shared between contexts.
5681 		 * Only create for the first PID to avoid debugfs log spamming
5682 		 * The printing code will anyway print all contexts for a given
5683 		 * PID so this is not a problem.
5684 		 */
5685 		proc->debugfs_entry = debugfs_create_file(strbuf, 0444,
5686 			binder_debugfs_dir_entry_proc,
5687 			(void *)(unsigned long)proc->pid,
5688 			&proc_fops);
5689 	}
5690 
5691 	if (binder_binderfs_dir_entry_proc && !existing_pid) {
5692 		char strbuf[11];
5693 		struct dentry *binderfs_entry;
5694 
5695 		snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
5696 		/*
5697 		 * Similar to debugfs, the process specific log file is shared
5698 		 * between contexts. Only create for the first PID.
5699 		 * This is ok since same as debugfs, the log file will contain
5700 		 * information on all contexts of a given PID.
5701 		 */
5702 		binderfs_entry = binderfs_create_file(binder_binderfs_dir_entry_proc,
5703 			strbuf, &proc_fops, (void *)(unsigned long)proc->pid);
5704 		if (!IS_ERR(binderfs_entry)) {
5705 			proc->binderfs_entry = binderfs_entry;
5706 		} else {
5707 			int error;
5708 
5709 			error = PTR_ERR(binderfs_entry);
5710 			pr_warn("Unable to create file %s in binderfs (error %d)\n",
5711 				strbuf, error);
5712 		}
5713 	}
5714 
5715 	return 0;
5716 }
5717 
binder_flush(struct file * filp,fl_owner_t id)5718 static int binder_flush(struct file *filp, fl_owner_t id)
5719 {
5720 	struct binder_proc *proc = filp->private_data;
5721 
5722 	binder_defer_work(proc, BINDER_DEFERRED_FLUSH);
5723 
5724 	return 0;
5725 }
5726 
binder_deferred_flush(struct binder_proc * proc)5727 static void binder_deferred_flush(struct binder_proc *proc)
5728 {
5729 	struct rb_node *n;
5730 	int wake_count = 0;
5731 
5732 	binder_inner_proc_lock(proc);
5733 	for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
5734 		struct binder_thread *thread = rb_entry(n, struct binder_thread, rb_node);
5735 
5736 		thread->looper_need_return = true;
5737 		if (thread->looper & BINDER_LOOPER_STATE_WAITING) {
5738 			wake_up_interruptible(&thread->wait);
5739 			wake_count++;
5740 		}
5741 	}
5742 	binder_inner_proc_unlock(proc);
5743 
5744 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5745 		     "binder_flush: %d woke %d threads\n", proc->pid,
5746 		     wake_count);
5747 }
5748 
binder_release(struct inode * nodp,struct file * filp)5749 static int binder_release(struct inode *nodp, struct file *filp)
5750 {
5751 	struct binder_proc *proc = filp->private_data;
5752 
5753 	debugfs_remove(proc->debugfs_entry);
5754 
5755 	if (proc->binderfs_entry) {
5756 		binderfs_remove_file(proc->binderfs_entry);
5757 		proc->binderfs_entry = NULL;
5758 	}
5759 
5760 	binder_defer_work(proc, BINDER_DEFERRED_RELEASE);
5761 
5762 	return 0;
5763 }
5764 
binder_node_release(struct binder_node * node,int refs)5765 static int binder_node_release(struct binder_node *node, int refs)
5766 {
5767 	struct binder_ref *ref;
5768 	int death = 0;
5769 	struct binder_proc *proc = node->proc;
5770 
5771 	binder_release_work(proc, &node->async_todo);
5772 
5773 	binder_node_lock(node);
5774 	binder_inner_proc_lock(proc);
5775 	binder_dequeue_work_ilocked(&node->work);
5776 	/*
5777 	 * The caller must have taken a temporary ref on the node,
5778 	 */
5779 	BUG_ON(!node->tmp_refs);
5780 	if (hlist_empty(&node->refs) && node->tmp_refs == 1) {
5781 		binder_inner_proc_unlock(proc);
5782 		binder_node_unlock(node);
5783 		binder_free_node(node);
5784 
5785 		return refs;
5786 	}
5787 
5788 	node->proc = NULL;
5789 	node->local_strong_refs = 0;
5790 	node->local_weak_refs = 0;
5791 	binder_inner_proc_unlock(proc);
5792 
5793 	spin_lock(&binder_dead_nodes_lock);
5794 	hlist_add_head(&node->dead_node, &binder_dead_nodes);
5795 	spin_unlock(&binder_dead_nodes_lock);
5796 
5797 	hlist_for_each_entry(ref, &node->refs, node_entry) {
5798 		refs++;
5799 		/*
5800 		 * Need the node lock to synchronize
5801 		 * with new notification requests and the
5802 		 * inner lock to synchronize with queued
5803 		 * death notifications.
5804 		 */
5805 		binder_inner_proc_lock(ref->proc);
5806 		if (!ref->death) {
5807 			binder_inner_proc_unlock(ref->proc);
5808 			continue;
5809 		}
5810 
5811 		death++;
5812 
5813 		BUG_ON(!list_empty(&ref->death->work.entry));
5814 		ref->death->work.type = BINDER_WORK_DEAD_BINDER;
5815 		binder_enqueue_work_ilocked(&ref->death->work,
5816 					    &ref->proc->todo);
5817 		binder_wakeup_proc_ilocked(ref->proc);
5818 		binder_inner_proc_unlock(ref->proc);
5819 	}
5820 
5821 	binder_debug(BINDER_DEBUG_DEAD_BINDER,
5822 		     "node %d now dead, refs %d, death %d\n",
5823 		     node->debug_id, refs, death);
5824 	binder_node_unlock(node);
5825 	binder_put_node(node);
5826 
5827 	return refs;
5828 }
5829 
binder_deferred_release(struct binder_proc * proc)5830 static void binder_deferred_release(struct binder_proc *proc)
5831 {
5832 	struct binder_context *context = proc->context;
5833 	struct rb_node *n;
5834 	int threads, nodes, incoming_refs, outgoing_refs, active_transactions;
5835 
5836 	mutex_lock(&binder_procs_lock);
5837 	hlist_del(&proc->proc_node);
5838 	mutex_unlock(&binder_procs_lock);
5839 
5840 	mutex_lock(&context->context_mgr_node_lock);
5841 	if (context->binder_context_mgr_node &&
5842 	    context->binder_context_mgr_node->proc == proc) {
5843 		binder_debug(BINDER_DEBUG_DEAD_BINDER,
5844 			     "%s: %d context_mgr_node gone\n",
5845 			     __func__, proc->pid);
5846 		context->binder_context_mgr_node = NULL;
5847 	}
5848 	mutex_unlock(&context->context_mgr_node_lock);
5849 	binder_inner_proc_lock(proc);
5850 	/*
5851 	 * Make sure proc stays alive after we
5852 	 * remove all the threads
5853 	 */
5854 	proc->tmp_ref++;
5855 
5856 	proc->is_dead = true;
5857 	proc->is_frozen = false;
5858 	proc->sync_recv = false;
5859 	proc->async_recv = false;
5860 	threads = 0;
5861 	active_transactions = 0;
5862 	while ((n = rb_first(&proc->threads))) {
5863 		struct binder_thread *thread;
5864 
5865 		thread = rb_entry(n, struct binder_thread, rb_node);
5866 		binder_inner_proc_unlock(proc);
5867 		threads++;
5868 		active_transactions += binder_thread_release(proc, thread);
5869 		binder_inner_proc_lock(proc);
5870 	}
5871 
5872 	nodes = 0;
5873 	incoming_refs = 0;
5874 	while ((n = rb_first(&proc->nodes))) {
5875 		struct binder_node *node;
5876 
5877 		node = rb_entry(n, struct binder_node, rb_node);
5878 		nodes++;
5879 		/*
5880 		 * take a temporary ref on the node before
5881 		 * calling binder_node_release() which will either
5882 		 * kfree() the node or call binder_put_node()
5883 		 */
5884 		binder_inc_node_tmpref_ilocked(node);
5885 		rb_erase(&node->rb_node, &proc->nodes);
5886 		binder_inner_proc_unlock(proc);
5887 		incoming_refs = binder_node_release(node, incoming_refs);
5888 		binder_inner_proc_lock(proc);
5889 	}
5890 	binder_inner_proc_unlock(proc);
5891 
5892 	outgoing_refs = 0;
5893 	binder_proc_lock(proc);
5894 	while ((n = rb_first(&proc->refs_by_desc))) {
5895 		struct binder_ref *ref;
5896 
5897 		ref = rb_entry(n, struct binder_ref, rb_node_desc);
5898 		outgoing_refs++;
5899 		binder_cleanup_ref_olocked(ref);
5900 		binder_proc_unlock(proc);
5901 		binder_free_ref(ref);
5902 		binder_proc_lock(proc);
5903 	}
5904 	binder_proc_unlock(proc);
5905 
5906 	binder_release_work(proc, &proc->todo);
5907 	binder_release_work(proc, &proc->delivered_death);
5908 
5909 	binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5910 		     "%s: %d threads %d, nodes %d (ref %d), refs %d, active transactions %d\n",
5911 		     __func__, proc->pid, threads, nodes, incoming_refs,
5912 		     outgoing_refs, active_transactions);
5913 
5914 	binder_proc_dec_tmpref(proc);
5915 }
5916 
binder_deferred_func(struct work_struct * work)5917 static void binder_deferred_func(struct work_struct *work)
5918 {
5919 	struct binder_proc *proc;
5920 
5921 	int defer;
5922 
5923 	do {
5924 		mutex_lock(&binder_deferred_lock);
5925 		if (!hlist_empty(&binder_deferred_list)) {
5926 			proc = hlist_entry(binder_deferred_list.first,
5927 					struct binder_proc, deferred_work_node);
5928 			hlist_del_init(&proc->deferred_work_node);
5929 			defer = proc->deferred_work;
5930 			proc->deferred_work = 0;
5931 		} else {
5932 			proc = NULL;
5933 			defer = 0;
5934 		}
5935 		mutex_unlock(&binder_deferred_lock);
5936 
5937 		if (defer & BINDER_DEFERRED_FLUSH)
5938 			binder_deferred_flush(proc);
5939 
5940 		if (defer & BINDER_DEFERRED_RELEASE)
5941 			binder_deferred_release(proc); /* frees proc */
5942 	} while (proc);
5943 }
5944 static DECLARE_WORK(binder_deferred_work, binder_deferred_func);
5945 
5946 static void
binder_defer_work(struct binder_proc * proc,enum binder_deferred_state defer)5947 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer)
5948 {
5949 	mutex_lock(&binder_deferred_lock);
5950 	proc->deferred_work |= defer;
5951 	if (hlist_unhashed(&proc->deferred_work_node)) {
5952 		hlist_add_head(&proc->deferred_work_node,
5953 				&binder_deferred_list);
5954 		schedule_work(&binder_deferred_work);
5955 	}
5956 	mutex_unlock(&binder_deferred_lock);
5957 }
5958 
print_binder_transaction_ilocked(struct seq_file * m,struct binder_proc * proc,const char * prefix,struct binder_transaction * t)5959 static void print_binder_transaction_ilocked(struct seq_file *m,
5960 					     struct binder_proc *proc,
5961 					     const char *prefix,
5962 					     struct binder_transaction *t)
5963 {
5964 	struct binder_proc *to_proc;
5965 	struct binder_buffer *buffer = t->buffer;
5966 	ktime_t current_time = ktime_get();
5967 
5968 	spin_lock(&t->lock);
5969 	to_proc = t->to_proc;
5970 	seq_printf(m,
5971 		   "%s %d: %pK from %d:%d to %d:%d code %x flags %x pri %ld r%d elapsed %lldms",
5972 		   prefix, t->debug_id, t,
5973 		   t->from_pid,
5974 		   t->from_tid,
5975 		   to_proc ? to_proc->pid : 0,
5976 		   t->to_thread ? t->to_thread->pid : 0,
5977 		   t->code, t->flags, t->priority, t->need_reply,
5978 		   ktime_ms_delta(current_time, t->start_time));
5979 	spin_unlock(&t->lock);
5980 
5981 	if (proc != to_proc) {
5982 		/*
5983 		 * Can only safely deref buffer if we are holding the
5984 		 * correct proc inner lock for this node
5985 		 */
5986 		seq_puts(m, "\n");
5987 		return;
5988 	}
5989 
5990 	if (buffer == NULL) {
5991 		seq_puts(m, " buffer free\n");
5992 		return;
5993 	}
5994 	if (buffer->target_node)
5995 		seq_printf(m, " node %d", buffer->target_node->debug_id);
5996 	seq_printf(m, " size %zd:%zd data %pK\n",
5997 		   buffer->data_size, buffer->offsets_size,
5998 		   buffer->user_data);
5999 }
6000 
print_binder_work_ilocked(struct seq_file * m,struct binder_proc * proc,const char * prefix,const char * transaction_prefix,struct binder_work * w)6001 static void print_binder_work_ilocked(struct seq_file *m,
6002 				     struct binder_proc *proc,
6003 				     const char *prefix,
6004 				     const char *transaction_prefix,
6005 				     struct binder_work *w)
6006 {
6007 	struct binder_node *node;
6008 	struct binder_transaction *t;
6009 
6010 	switch (w->type) {
6011 	case BINDER_WORK_TRANSACTION:
6012 		t = container_of(w, struct binder_transaction, work);
6013 		print_binder_transaction_ilocked(
6014 				m, proc, transaction_prefix, t);
6015 		break;
6016 	case BINDER_WORK_RETURN_ERROR: {
6017 		struct binder_error *e = container_of(
6018 				w, struct binder_error, work);
6019 
6020 		seq_printf(m, "%stransaction error: %u\n",
6021 			   prefix, e->cmd);
6022 	} break;
6023 	case BINDER_WORK_TRANSACTION_COMPLETE:
6024 		seq_printf(m, "%stransaction complete\n", prefix);
6025 		break;
6026 	case BINDER_WORK_NODE:
6027 		node = container_of(w, struct binder_node, work);
6028 		seq_printf(m, "%snode work %d: u%016llx c%016llx\n",
6029 			   prefix, node->debug_id,
6030 			   (u64)node->ptr, (u64)node->cookie);
6031 		break;
6032 	case BINDER_WORK_DEAD_BINDER:
6033 		seq_printf(m, "%shas dead binder\n", prefix);
6034 		break;
6035 	case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
6036 		seq_printf(m, "%shas cleared dead binder\n", prefix);
6037 		break;
6038 	case BINDER_WORK_CLEAR_DEATH_NOTIFICATION:
6039 		seq_printf(m, "%shas cleared death notification\n", prefix);
6040 		break;
6041 	default:
6042 		seq_printf(m, "%sunknown work: type %d\n", prefix, w->type);
6043 		break;
6044 	}
6045 }
6046 
print_binder_thread_ilocked(struct seq_file * m,struct binder_thread * thread,int print_always)6047 static void print_binder_thread_ilocked(struct seq_file *m,
6048 					struct binder_thread *thread,
6049 					int print_always)
6050 {
6051 	struct binder_transaction *t;
6052 	struct binder_work *w;
6053 	size_t start_pos = m->count;
6054 	size_t header_pos;
6055 
6056 	seq_printf(m, "  thread %d: l %02x need_return %d tr %d\n",
6057 			thread->pid, thread->looper,
6058 			thread->looper_need_return,
6059 			atomic_read(&thread->tmp_ref));
6060 	header_pos = m->count;
6061 	t = thread->transaction_stack;
6062 	while (t) {
6063 		if (t->from == thread) {
6064 			print_binder_transaction_ilocked(m, thread->proc,
6065 					"    outgoing transaction", t);
6066 			t = t->from_parent;
6067 		} else if (t->to_thread == thread) {
6068 			print_binder_transaction_ilocked(m, thread->proc,
6069 						 "    incoming transaction", t);
6070 			t = t->to_parent;
6071 		} else {
6072 			print_binder_transaction_ilocked(m, thread->proc,
6073 					"    bad transaction", t);
6074 			t = NULL;
6075 		}
6076 	}
6077 	list_for_each_entry(w, &thread->todo, entry) {
6078 		print_binder_work_ilocked(m, thread->proc, "    ",
6079 					  "    pending transaction", w);
6080 	}
6081 	if (!print_always && m->count == header_pos)
6082 		m->count = start_pos;
6083 }
6084 
print_binder_node_nilocked(struct seq_file * m,struct binder_node * node)6085 static void print_binder_node_nilocked(struct seq_file *m,
6086 				       struct binder_node *node)
6087 {
6088 	struct binder_ref *ref;
6089 	struct binder_work *w;
6090 	int count;
6091 
6092 	count = 0;
6093 	hlist_for_each_entry(ref, &node->refs, node_entry)
6094 		count++;
6095 
6096 	seq_printf(m, "  node %d: u%016llx c%016llx hs %d hw %d ls %d lw %d is %d iw %d tr %d",
6097 		   node->debug_id, (u64)node->ptr, (u64)node->cookie,
6098 		   node->has_strong_ref, node->has_weak_ref,
6099 		   node->local_strong_refs, node->local_weak_refs,
6100 		   node->internal_strong_refs, count, node->tmp_refs);
6101 	if (count) {
6102 		seq_puts(m, " proc");
6103 		hlist_for_each_entry(ref, &node->refs, node_entry)
6104 			seq_printf(m, " %d", ref->proc->pid);
6105 	}
6106 	seq_puts(m, "\n");
6107 	if (node->proc) {
6108 		list_for_each_entry(w, &node->async_todo, entry)
6109 			print_binder_work_ilocked(m, node->proc, "    ",
6110 					  "    pending async transaction", w);
6111 	}
6112 }
6113 
print_binder_ref_olocked(struct seq_file * m,struct binder_ref * ref)6114 static void print_binder_ref_olocked(struct seq_file *m,
6115 				     struct binder_ref *ref)
6116 {
6117 	binder_node_lock(ref->node);
6118 	seq_printf(m, "  ref %d: desc %d %snode %d s %d w %d d %pK\n",
6119 		   ref->data.debug_id, ref->data.desc,
6120 		   ref->node->proc ? "" : "dead ",
6121 		   ref->node->debug_id, ref->data.strong,
6122 		   ref->data.weak, ref->death);
6123 	binder_node_unlock(ref->node);
6124 }
6125 
print_binder_proc(struct seq_file * m,struct binder_proc * proc,int print_all)6126 static void print_binder_proc(struct seq_file *m,
6127 			      struct binder_proc *proc, int print_all)
6128 {
6129 	struct binder_work *w;
6130 	struct rb_node *n;
6131 	size_t start_pos = m->count;
6132 	size_t header_pos;
6133 	struct binder_node *last_node = NULL;
6134 
6135 	seq_printf(m, "proc %d\n", proc->pid);
6136 	seq_printf(m, "context %s\n", proc->context->name);
6137 	header_pos = m->count;
6138 
6139 	binder_inner_proc_lock(proc);
6140 	for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n))
6141 		print_binder_thread_ilocked(m, rb_entry(n, struct binder_thread,
6142 						rb_node), print_all);
6143 
6144 	for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) {
6145 		struct binder_node *node = rb_entry(n, struct binder_node,
6146 						    rb_node);
6147 		if (!print_all && !node->has_async_transaction)
6148 			continue;
6149 
6150 		/*
6151 		 * take a temporary reference on the node so it
6152 		 * survives and isn't removed from the tree
6153 		 * while we print it.
6154 		 */
6155 		binder_inc_node_tmpref_ilocked(node);
6156 		/* Need to drop inner lock to take node lock */
6157 		binder_inner_proc_unlock(proc);
6158 		if (last_node)
6159 			binder_put_node(last_node);
6160 		binder_node_inner_lock(node);
6161 		print_binder_node_nilocked(m, node);
6162 		binder_node_inner_unlock(node);
6163 		last_node = node;
6164 		binder_inner_proc_lock(proc);
6165 	}
6166 	binder_inner_proc_unlock(proc);
6167 	if (last_node)
6168 		binder_put_node(last_node);
6169 
6170 	if (print_all) {
6171 		binder_proc_lock(proc);
6172 		for (n = rb_first(&proc->refs_by_desc);
6173 		     n != NULL;
6174 		     n = rb_next(n))
6175 			print_binder_ref_olocked(m, rb_entry(n,
6176 							    struct binder_ref,
6177 							    rb_node_desc));
6178 		binder_proc_unlock(proc);
6179 	}
6180 	binder_alloc_print_allocated(m, &proc->alloc);
6181 	binder_inner_proc_lock(proc);
6182 	list_for_each_entry(w, &proc->todo, entry)
6183 		print_binder_work_ilocked(m, proc, "  ",
6184 					  "  pending transaction", w);
6185 	list_for_each_entry(w, &proc->delivered_death, entry) {
6186 		seq_puts(m, "  has delivered dead binder\n");
6187 		break;
6188 	}
6189 	binder_inner_proc_unlock(proc);
6190 	if (!print_all && m->count == header_pos)
6191 		m->count = start_pos;
6192 }
6193 
6194 static const char * const binder_return_strings[] = {
6195 	"BR_ERROR",
6196 	"BR_OK",
6197 	"BR_TRANSACTION",
6198 	"BR_REPLY",
6199 	"BR_ACQUIRE_RESULT",
6200 	"BR_DEAD_REPLY",
6201 	"BR_TRANSACTION_COMPLETE",
6202 	"BR_INCREFS",
6203 	"BR_ACQUIRE",
6204 	"BR_RELEASE",
6205 	"BR_DECREFS",
6206 	"BR_ATTEMPT_ACQUIRE",
6207 	"BR_NOOP",
6208 	"BR_SPAWN_LOOPER",
6209 	"BR_FINISHED",
6210 	"BR_DEAD_BINDER",
6211 	"BR_CLEAR_DEATH_NOTIFICATION_DONE",
6212 	"BR_FAILED_REPLY",
6213 	"BR_FROZEN_REPLY",
6214 	"BR_ONEWAY_SPAM_SUSPECT",
6215 	"BR_TRANSACTION_PENDING_FROZEN"
6216 };
6217 
6218 static const char * const binder_command_strings[] = {
6219 	"BC_TRANSACTION",
6220 	"BC_REPLY",
6221 	"BC_ACQUIRE_RESULT",
6222 	"BC_FREE_BUFFER",
6223 	"BC_INCREFS",
6224 	"BC_ACQUIRE",
6225 	"BC_RELEASE",
6226 	"BC_DECREFS",
6227 	"BC_INCREFS_DONE",
6228 	"BC_ACQUIRE_DONE",
6229 	"BC_ATTEMPT_ACQUIRE",
6230 	"BC_REGISTER_LOOPER",
6231 	"BC_ENTER_LOOPER",
6232 	"BC_EXIT_LOOPER",
6233 	"BC_REQUEST_DEATH_NOTIFICATION",
6234 	"BC_CLEAR_DEATH_NOTIFICATION",
6235 	"BC_DEAD_BINDER_DONE",
6236 	"BC_TRANSACTION_SG",
6237 	"BC_REPLY_SG",
6238 };
6239 
6240 static const char * const binder_objstat_strings[] = {
6241 	"proc",
6242 	"thread",
6243 	"node",
6244 	"ref",
6245 	"death",
6246 	"transaction",
6247 	"transaction_complete"
6248 };
6249 
print_binder_stats(struct seq_file * m,const char * prefix,struct binder_stats * stats)6250 static void print_binder_stats(struct seq_file *m, const char *prefix,
6251 			       struct binder_stats *stats)
6252 {
6253 	int i;
6254 
6255 	BUILD_BUG_ON(ARRAY_SIZE(stats->bc) !=
6256 		     ARRAY_SIZE(binder_command_strings));
6257 	for (i = 0; i < ARRAY_SIZE(stats->bc); i++) {
6258 		int temp = atomic_read(&stats->bc[i]);
6259 
6260 		if (temp)
6261 			seq_printf(m, "%s%s: %d\n", prefix,
6262 				   binder_command_strings[i], temp);
6263 	}
6264 
6265 	BUILD_BUG_ON(ARRAY_SIZE(stats->br) !=
6266 		     ARRAY_SIZE(binder_return_strings));
6267 	for (i = 0; i < ARRAY_SIZE(stats->br); i++) {
6268 		int temp = atomic_read(&stats->br[i]);
6269 
6270 		if (temp)
6271 			seq_printf(m, "%s%s: %d\n", prefix,
6272 				   binder_return_strings[i], temp);
6273 	}
6274 
6275 	BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
6276 		     ARRAY_SIZE(binder_objstat_strings));
6277 	BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
6278 		     ARRAY_SIZE(stats->obj_deleted));
6279 	for (i = 0; i < ARRAY_SIZE(stats->obj_created); i++) {
6280 		int created = atomic_read(&stats->obj_created[i]);
6281 		int deleted = atomic_read(&stats->obj_deleted[i]);
6282 
6283 		if (created || deleted)
6284 			seq_printf(m, "%s%s: active %d total %d\n",
6285 				prefix,
6286 				binder_objstat_strings[i],
6287 				created - deleted,
6288 				created);
6289 	}
6290 }
6291 
print_binder_proc_stats(struct seq_file * m,struct binder_proc * proc)6292 static void print_binder_proc_stats(struct seq_file *m,
6293 				    struct binder_proc *proc)
6294 {
6295 	struct binder_work *w;
6296 	struct binder_thread *thread;
6297 	struct rb_node *n;
6298 	int count, strong, weak, ready_threads;
6299 	size_t free_async_space =
6300 		binder_alloc_get_free_async_space(&proc->alloc);
6301 
6302 	seq_printf(m, "proc %d\n", proc->pid);
6303 	seq_printf(m, "context %s\n", proc->context->name);
6304 	count = 0;
6305 	ready_threads = 0;
6306 	binder_inner_proc_lock(proc);
6307 	for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n))
6308 		count++;
6309 
6310 	list_for_each_entry(thread, &proc->waiting_threads, waiting_thread_node)
6311 		ready_threads++;
6312 
6313 	seq_printf(m, "  threads: %d\n", count);
6314 	seq_printf(m, "  requested threads: %d+%d/%d\n"
6315 			"  ready threads %d\n"
6316 			"  free async space %zd\n", proc->requested_threads,
6317 			proc->requested_threads_started, proc->max_threads,
6318 			ready_threads,
6319 			free_async_space);
6320 	count = 0;
6321 	for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n))
6322 		count++;
6323 	binder_inner_proc_unlock(proc);
6324 	seq_printf(m, "  nodes: %d\n", count);
6325 	count = 0;
6326 	strong = 0;
6327 	weak = 0;
6328 	binder_proc_lock(proc);
6329 	for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) {
6330 		struct binder_ref *ref = rb_entry(n, struct binder_ref,
6331 						  rb_node_desc);
6332 		count++;
6333 		strong += ref->data.strong;
6334 		weak += ref->data.weak;
6335 	}
6336 	binder_proc_unlock(proc);
6337 	seq_printf(m, "  refs: %d s %d w %d\n", count, strong, weak);
6338 
6339 	count = binder_alloc_get_allocated_count(&proc->alloc);
6340 	seq_printf(m, "  buffers: %d\n", count);
6341 
6342 	binder_alloc_print_pages(m, &proc->alloc);
6343 
6344 	count = 0;
6345 	binder_inner_proc_lock(proc);
6346 	list_for_each_entry(w, &proc->todo, entry) {
6347 		if (w->type == BINDER_WORK_TRANSACTION)
6348 			count++;
6349 	}
6350 	binder_inner_proc_unlock(proc);
6351 	seq_printf(m, "  pending transactions: %d\n", count);
6352 
6353 	print_binder_stats(m, "  ", &proc->stats);
6354 }
6355 
state_show(struct seq_file * m,void * unused)6356 static int state_show(struct seq_file *m, void *unused)
6357 {
6358 	struct binder_proc *proc;
6359 	struct binder_node *node;
6360 	struct binder_node *last_node = NULL;
6361 
6362 	seq_puts(m, "binder state:\n");
6363 
6364 	spin_lock(&binder_dead_nodes_lock);
6365 	if (!hlist_empty(&binder_dead_nodes))
6366 		seq_puts(m, "dead nodes:\n");
6367 	hlist_for_each_entry(node, &binder_dead_nodes, dead_node) {
6368 		/*
6369 		 * take a temporary reference on the node so it
6370 		 * survives and isn't removed from the list
6371 		 * while we print it.
6372 		 */
6373 		node->tmp_refs++;
6374 		spin_unlock(&binder_dead_nodes_lock);
6375 		if (last_node)
6376 			binder_put_node(last_node);
6377 		binder_node_lock(node);
6378 		print_binder_node_nilocked(m, node);
6379 		binder_node_unlock(node);
6380 		last_node = node;
6381 		spin_lock(&binder_dead_nodes_lock);
6382 	}
6383 	spin_unlock(&binder_dead_nodes_lock);
6384 	if (last_node)
6385 		binder_put_node(last_node);
6386 
6387 	mutex_lock(&binder_procs_lock);
6388 	hlist_for_each_entry(proc, &binder_procs, proc_node)
6389 		print_binder_proc(m, proc, 1);
6390 	mutex_unlock(&binder_procs_lock);
6391 
6392 	return 0;
6393 }
6394 
stats_show(struct seq_file * m,void * unused)6395 static int stats_show(struct seq_file *m, void *unused)
6396 {
6397 	struct binder_proc *proc;
6398 
6399 	seq_puts(m, "binder stats:\n");
6400 
6401 	print_binder_stats(m, "", &binder_stats);
6402 
6403 	mutex_lock(&binder_procs_lock);
6404 	hlist_for_each_entry(proc, &binder_procs, proc_node)
6405 		print_binder_proc_stats(m, proc);
6406 	mutex_unlock(&binder_procs_lock);
6407 
6408 	return 0;
6409 }
6410 
transactions_show(struct seq_file * m,void * unused)6411 static int transactions_show(struct seq_file *m, void *unused)
6412 {
6413 	struct binder_proc *proc;
6414 
6415 	seq_puts(m, "binder transactions:\n");
6416 	mutex_lock(&binder_procs_lock);
6417 	hlist_for_each_entry(proc, &binder_procs, proc_node)
6418 		print_binder_proc(m, proc, 0);
6419 	mutex_unlock(&binder_procs_lock);
6420 
6421 	return 0;
6422 }
6423 
proc_show(struct seq_file * m,void * unused)6424 static int proc_show(struct seq_file *m, void *unused)
6425 {
6426 	struct binder_proc *itr;
6427 	int pid = (unsigned long)m->private;
6428 
6429 	mutex_lock(&binder_procs_lock);
6430 	hlist_for_each_entry(itr, &binder_procs, proc_node) {
6431 		if (itr->pid == pid) {
6432 			seq_puts(m, "binder proc state:\n");
6433 			print_binder_proc(m, itr, 1);
6434 		}
6435 	}
6436 	mutex_unlock(&binder_procs_lock);
6437 
6438 	return 0;
6439 }
6440 
print_binder_transaction_log_entry(struct seq_file * m,struct binder_transaction_log_entry * e)6441 static void print_binder_transaction_log_entry(struct seq_file *m,
6442 					struct binder_transaction_log_entry *e)
6443 {
6444 	int debug_id = READ_ONCE(e->debug_id_done);
6445 	/*
6446 	 * read barrier to guarantee debug_id_done read before
6447 	 * we print the log values
6448 	 */
6449 	smp_rmb();
6450 	seq_printf(m,
6451 		   "%d: %s from %d:%d to %d:%d context %s node %d handle %d size %d:%d ret %d/%d l=%d",
6452 		   e->debug_id, (e->call_type == 2) ? "reply" :
6453 		   ((e->call_type == 1) ? "async" : "call "), e->from_proc,
6454 		   e->from_thread, e->to_proc, e->to_thread, e->context_name,
6455 		   e->to_node, e->target_handle, e->data_size, e->offsets_size,
6456 		   e->return_error, e->return_error_param,
6457 		   e->return_error_line);
6458 	/*
6459 	 * read-barrier to guarantee read of debug_id_done after
6460 	 * done printing the fields of the entry
6461 	 */
6462 	smp_rmb();
6463 	seq_printf(m, debug_id && debug_id == READ_ONCE(e->debug_id_done) ?
6464 			"\n" : " (incomplete)\n");
6465 }
6466 
transaction_log_show(struct seq_file * m,void * unused)6467 static int transaction_log_show(struct seq_file *m, void *unused)
6468 {
6469 	struct binder_transaction_log *log = m->private;
6470 	unsigned int log_cur = atomic_read(&log->cur);
6471 	unsigned int count;
6472 	unsigned int cur;
6473 	int i;
6474 
6475 	count = log_cur + 1;
6476 	cur = count < ARRAY_SIZE(log->entry) && !log->full ?
6477 		0 : count % ARRAY_SIZE(log->entry);
6478 	if (count > ARRAY_SIZE(log->entry) || log->full)
6479 		count = ARRAY_SIZE(log->entry);
6480 	for (i = 0; i < count; i++) {
6481 		unsigned int index = cur++ % ARRAY_SIZE(log->entry);
6482 
6483 		print_binder_transaction_log_entry(m, &log->entry[index]);
6484 	}
6485 	return 0;
6486 }
6487 
6488 const struct file_operations binder_fops = {
6489 	.owner = THIS_MODULE,
6490 	.poll = binder_poll,
6491 	.unlocked_ioctl = binder_ioctl,
6492 	.compat_ioctl = compat_ptr_ioctl,
6493 	.mmap = binder_mmap,
6494 	.open = binder_open,
6495 	.flush = binder_flush,
6496 	.release = binder_release,
6497 };
6498 
6499 DEFINE_SHOW_ATTRIBUTE(state);
6500 DEFINE_SHOW_ATTRIBUTE(stats);
6501 DEFINE_SHOW_ATTRIBUTE(transactions);
6502 DEFINE_SHOW_ATTRIBUTE(transaction_log);
6503 
6504 const struct binder_debugfs_entry binder_debugfs_entries[] = {
6505 	{
6506 		.name = "state",
6507 		.mode = 0444,
6508 		.fops = &state_fops,
6509 		.data = NULL,
6510 	},
6511 	{
6512 		.name = "stats",
6513 		.mode = 0444,
6514 		.fops = &stats_fops,
6515 		.data = NULL,
6516 	},
6517 	{
6518 		.name = "transactions",
6519 		.mode = 0444,
6520 		.fops = &transactions_fops,
6521 		.data = NULL,
6522 	},
6523 	{
6524 		.name = "transaction_log",
6525 		.mode = 0444,
6526 		.fops = &transaction_log_fops,
6527 		.data = &binder_transaction_log,
6528 	},
6529 	{
6530 		.name = "failed_transaction_log",
6531 		.mode = 0444,
6532 		.fops = &transaction_log_fops,
6533 		.data = &binder_transaction_log_failed,
6534 	},
6535 	{} /* terminator */
6536 };
6537 
init_binder_device(const char * name)6538 static int __init init_binder_device(const char *name)
6539 {
6540 	int ret;
6541 	struct binder_device *binder_device;
6542 
6543 	binder_device = kzalloc(sizeof(*binder_device), GFP_KERNEL);
6544 	if (!binder_device)
6545 		return -ENOMEM;
6546 
6547 	binder_device->miscdev.fops = &binder_fops;
6548 	binder_device->miscdev.minor = MISC_DYNAMIC_MINOR;
6549 	binder_device->miscdev.name = name;
6550 
6551 	refcount_set(&binder_device->ref, 1);
6552 	binder_device->context.binder_context_mgr_uid = INVALID_UID;
6553 	binder_device->context.name = name;
6554 	mutex_init(&binder_device->context.context_mgr_node_lock);
6555 
6556 	ret = misc_register(&binder_device->miscdev);
6557 	if (ret < 0) {
6558 		kfree(binder_device);
6559 		return ret;
6560 	}
6561 
6562 	hlist_add_head(&binder_device->hlist, &binder_devices);
6563 
6564 	return ret;
6565 }
6566 
binder_init(void)6567 static int __init binder_init(void)
6568 {
6569 	int ret;
6570 	char *device_name, *device_tmp;
6571 	struct binder_device *device;
6572 	struct hlist_node *tmp;
6573 	char *device_names = NULL;
6574 	const struct binder_debugfs_entry *db_entry;
6575 
6576 	ret = binder_alloc_shrinker_init();
6577 	if (ret)
6578 		return ret;
6579 
6580 	atomic_set(&binder_transaction_log.cur, ~0U);
6581 	atomic_set(&binder_transaction_log_failed.cur, ~0U);
6582 
6583 	binder_debugfs_dir_entry_root = debugfs_create_dir("binder", NULL);
6584 
6585 	binder_for_each_debugfs_entry(db_entry)
6586 		debugfs_create_file(db_entry->name,
6587 					db_entry->mode,
6588 					binder_debugfs_dir_entry_root,
6589 					db_entry->data,
6590 					db_entry->fops);
6591 
6592 	binder_debugfs_dir_entry_proc = debugfs_create_dir("proc",
6593 						binder_debugfs_dir_entry_root);
6594 
6595 	if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS) &&
6596 	    strcmp(binder_devices_param, "") != 0) {
6597 		/*
6598 		* Copy the module_parameter string, because we don't want to
6599 		* tokenize it in-place.
6600 		 */
6601 		device_names = kstrdup(binder_devices_param, GFP_KERNEL);
6602 		if (!device_names) {
6603 			ret = -ENOMEM;
6604 			goto err_alloc_device_names_failed;
6605 		}
6606 
6607 		device_tmp = device_names;
6608 		while ((device_name = strsep(&device_tmp, ","))) {
6609 			ret = init_binder_device(device_name);
6610 			if (ret)
6611 				goto err_init_binder_device_failed;
6612 		}
6613 	}
6614 
6615 	ret = init_binderfs();
6616 	if (ret)
6617 		goto err_init_binder_device_failed;
6618 
6619 	return ret;
6620 
6621 err_init_binder_device_failed:
6622 	hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) {
6623 		misc_deregister(&device->miscdev);
6624 		hlist_del(&device->hlist);
6625 		kfree(device);
6626 	}
6627 
6628 	kfree(device_names);
6629 
6630 err_alloc_device_names_failed:
6631 	debugfs_remove_recursive(binder_debugfs_dir_entry_root);
6632 	binder_alloc_shrinker_exit();
6633 
6634 	return ret;
6635 }
6636 
6637 device_initcall(binder_init);
6638 
6639 #define CREATE_TRACE_POINTS
6640 #include "binder_trace.h"
6641 
6642 MODULE_LICENSE("GPL v2");
6643