xref: /openbmc/linux/fs/proc/array.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/proc/array.c
4  *
5  *  Copyright (C) 1992  by Linus Torvalds
6  *  based on ideas by Darren Senn
7  *
8  * Fixes:
9  * Michael. K. Johnson: stat,statm extensions.
10  *                      <johnsonm@stolaf.edu>
11  *
12  * Pauline Middelink :  Made cmdline,envline only break at '\0's, to
13  *                      make sure SET_PROCTITLE works. Also removed
14  *                      bad '!' which forced address recalculation for
15  *                      EVERY character on the current page.
16  *                      <middelin@polyware.iaf.nl>
17  *
18  * Danny ter Haar    :	added cpuinfo
19  *			<dth@cistron.nl>
20  *
21  * Alessandro Rubini :  profile extension.
22  *                      <rubini@ipvvis.unipv.it>
23  *
24  * Jeff Tranter      :  added BogoMips field to cpuinfo
25  *                      <Jeff_Tranter@Mitel.COM>
26  *
27  * Bruno Haible      :  remove 4K limit for the maps file
28  *			<haible@ma2s2.mathematik.uni-karlsruhe.de>
29  *
30  * Yves Arrouye      :  remove removal of trailing spaces in get_array.
31  *			<Yves.Arrouye@marin.fdn.fr>
32  *
33  * Jerome Forissier  :  added per-CPU time information to /proc/stat
34  *                      and /proc/<pid>/cpu extension
35  *                      <forissier@isia.cma.fr>
36  *			- Incorporation and non-SMP safe operation
37  *			of forissier patch in 2.1.78 by
38  *			Hans Marcus <crowbar@concepts.nl>
39  *
40  * aeb@cwi.nl        :  /proc/partitions
41  *
42  *
43  * Alan Cox	     :  security fixes.
44  *			<alan@lxorguk.ukuu.org.uk>
45  *
46  * Al Viro           :  safe handling of mm_struct
47  *
48  * Gerhard Wichert   :  added BIGMEM support
49  * Siemens AG           <Gerhard.Wichert@pdb.siemens.de>
50  *
51  * Al Viro & Jeff Garzik :  moved most of the thing into base.c and
52  *			 :  proc_misc.c. The rest may eventually go into
53  *			 :  base.c too.
54  */
55 
56 #include <linux/types.h>
57 #include <linux/errno.h>
58 #include <linux/time.h>
59 #include <linux/time_namespace.h>
60 #include <linux/kernel.h>
61 #include <linux/kernel_stat.h>
62 #include <linux/tty.h>
63 #include <linux/string.h>
64 #include <linux/mman.h>
65 #include <linux/sched/mm.h>
66 #include <linux/sched/numa_balancing.h>
67 #include <linux/sched/task_stack.h>
68 #include <linux/sched/task.h>
69 #include <linux/sched/cputime.h>
70 #include <linux/proc_fs.h>
71 #include <linux/ioport.h>
72 #include <linux/uaccess.h>
73 #include <linux/io.h>
74 #include <linux/mm.h>
75 #include <linux/hugetlb.h>
76 #include <linux/pagemap.h>
77 #include <linux/swap.h>
78 #include <linux/smp.h>
79 #include <linux/signal.h>
80 #include <linux/highmem.h>
81 #include <linux/file.h>
82 #include <linux/fdtable.h>
83 #include <linux/times.h>
84 #include <linux/cpuset.h>
85 #include <linux/rcupdate.h>
86 #include <linux/delayacct.h>
87 #include <linux/seq_file.h>
88 #include <linux/pid_namespace.h>
89 #include <linux/prctl.h>
90 #include <linux/ptrace.h>
91 #include <linux/tracehook.h>
92 #include <linux/string_helpers.h>
93 #include <linux/user_namespace.h>
94 #include <linux/fs_struct.h>
95 #include <linux/kthread.h>
96 
97 #include <asm/processor.h>
98 #include "internal.h"
99 
100 void proc_task_name(struct seq_file *m, struct task_struct *p, bool escape)
101 {
102 	char tcomm[64];
103 
104 	if (p->flags & PF_WQ_WORKER)
105 		wq_worker_comm(tcomm, sizeof(tcomm), p);
106 	else if (p->flags & PF_KTHREAD)
107 		get_kthread_comm(tcomm, sizeof(tcomm), p);
108 	else
109 		__get_task_comm(tcomm, sizeof(tcomm), p);
110 
111 	if (escape)
112 		seq_escape_str(m, tcomm, ESCAPE_SPACE | ESCAPE_SPECIAL, "\n\\");
113 	else
114 		seq_printf(m, "%.64s", tcomm);
115 }
116 
117 /*
118  * The task state array is a strange "bitmap" of
119  * reasons to sleep. Thus "running" is zero, and
120  * you can test for combinations of others with
121  * simple bit tests.
122  */
123 static const char * const task_state_array[] = {
124 
125 	/* states in TASK_REPORT: */
126 	"R (running)",		/* 0x00 */
127 	"S (sleeping)",		/* 0x01 */
128 	"D (disk sleep)",	/* 0x02 */
129 	"T (stopped)",		/* 0x04 */
130 	"t (tracing stop)",	/* 0x08 */
131 	"X (dead)",		/* 0x10 */
132 	"Z (zombie)",		/* 0x20 */
133 	"P (parked)",		/* 0x40 */
134 
135 	/* states beyond TASK_REPORT: */
136 	"I (idle)",		/* 0x80 */
137 };
138 
139 static inline const char *get_task_state(struct task_struct *tsk)
140 {
141 	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != ARRAY_SIZE(task_state_array));
142 	return task_state_array[task_state_index(tsk)];
143 }
144 
145 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
146 				struct pid *pid, struct task_struct *p)
147 {
148 	struct user_namespace *user_ns = seq_user_ns(m);
149 	struct group_info *group_info;
150 	int g, umask = -1;
151 	struct task_struct *tracer;
152 	const struct cred *cred;
153 	pid_t ppid, tpid = 0, tgid, ngid;
154 	unsigned int max_fds = 0;
155 
156 	rcu_read_lock();
157 	ppid = pid_alive(p) ?
158 		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
159 
160 	tracer = ptrace_parent(p);
161 	if (tracer)
162 		tpid = task_pid_nr_ns(tracer, ns);
163 
164 	tgid = task_tgid_nr_ns(p, ns);
165 	ngid = task_numa_group_id(p);
166 	cred = get_task_cred(p);
167 
168 	task_lock(p);
169 	if (p->fs)
170 		umask = p->fs->umask;
171 	if (p->files)
172 		max_fds = files_fdtable(p->files)->max_fds;
173 	task_unlock(p);
174 	rcu_read_unlock();
175 
176 	if (umask >= 0)
177 		seq_printf(m, "Umask:\t%#04o\n", umask);
178 	seq_puts(m, "State:\t");
179 	seq_puts(m, get_task_state(p));
180 
181 	seq_put_decimal_ull(m, "\nTgid:\t", tgid);
182 	seq_put_decimal_ull(m, "\nNgid:\t", ngid);
183 	seq_put_decimal_ull(m, "\nPid:\t", pid_nr_ns(pid, ns));
184 	seq_put_decimal_ull(m, "\nPPid:\t", ppid);
185 	seq_put_decimal_ull(m, "\nTracerPid:\t", tpid);
186 	seq_put_decimal_ull(m, "\nUid:\t", from_kuid_munged(user_ns, cred->uid));
187 	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->euid));
188 	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->suid));
189 	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->fsuid));
190 	seq_put_decimal_ull(m, "\nGid:\t", from_kgid_munged(user_ns, cred->gid));
191 	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->egid));
192 	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->sgid));
193 	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->fsgid));
194 	seq_put_decimal_ull(m, "\nFDSize:\t", max_fds);
195 
196 	seq_puts(m, "\nGroups:\t");
197 	group_info = cred->group_info;
198 	for (g = 0; g < group_info->ngroups; g++)
199 		seq_put_decimal_ull(m, g ? " " : "",
200 				from_kgid_munged(user_ns, group_info->gid[g]));
201 	put_cred(cred);
202 	/* Trailing space shouldn't have been added in the first place. */
203 	seq_putc(m, ' ');
204 
205 #ifdef CONFIG_PID_NS
206 	seq_puts(m, "\nNStgid:");
207 	for (g = ns->level; g <= pid->level; g++)
208 		seq_put_decimal_ull(m, "\t", task_tgid_nr_ns(p, pid->numbers[g].ns));
209 	seq_puts(m, "\nNSpid:");
210 	for (g = ns->level; g <= pid->level; g++)
211 		seq_put_decimal_ull(m, "\t", task_pid_nr_ns(p, pid->numbers[g].ns));
212 	seq_puts(m, "\nNSpgid:");
213 	for (g = ns->level; g <= pid->level; g++)
214 		seq_put_decimal_ull(m, "\t", task_pgrp_nr_ns(p, pid->numbers[g].ns));
215 	seq_puts(m, "\nNSsid:");
216 	for (g = ns->level; g <= pid->level; g++)
217 		seq_put_decimal_ull(m, "\t", task_session_nr_ns(p, pid->numbers[g].ns));
218 #endif
219 	seq_putc(m, '\n');
220 }
221 
222 void render_sigset_t(struct seq_file *m, const char *header,
223 				sigset_t *set)
224 {
225 	int i;
226 
227 	seq_puts(m, header);
228 
229 	i = _NSIG;
230 	do {
231 		int x = 0;
232 
233 		i -= 4;
234 		if (sigismember(set, i+1)) x |= 1;
235 		if (sigismember(set, i+2)) x |= 2;
236 		if (sigismember(set, i+3)) x |= 4;
237 		if (sigismember(set, i+4)) x |= 8;
238 		seq_putc(m, hex_asc[x]);
239 	} while (i >= 4);
240 
241 	seq_putc(m, '\n');
242 }
243 
244 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *sigign,
245 				    sigset_t *sigcatch)
246 {
247 	struct k_sigaction *k;
248 	int i;
249 
250 	k = p->sighand->action;
251 	for (i = 1; i <= _NSIG; ++i, ++k) {
252 		if (k->sa.sa_handler == SIG_IGN)
253 			sigaddset(sigign, i);
254 		else if (k->sa.sa_handler != SIG_DFL)
255 			sigaddset(sigcatch, i);
256 	}
257 }
258 
259 static inline void task_sig(struct seq_file *m, struct task_struct *p)
260 {
261 	unsigned long flags;
262 	sigset_t pending, shpending, blocked, ignored, caught;
263 	int num_threads = 0;
264 	unsigned int qsize = 0;
265 	unsigned long qlim = 0;
266 
267 	sigemptyset(&pending);
268 	sigemptyset(&shpending);
269 	sigemptyset(&blocked);
270 	sigemptyset(&ignored);
271 	sigemptyset(&caught);
272 
273 	if (lock_task_sighand(p, &flags)) {
274 		pending = p->pending.signal;
275 		shpending = p->signal->shared_pending.signal;
276 		blocked = p->blocked;
277 		collect_sigign_sigcatch(p, &ignored, &caught);
278 		num_threads = get_nr_threads(p);
279 		rcu_read_lock();  /* FIXME: is this correct? */
280 		qsize = get_ucounts_value(task_ucounts(p), UCOUNT_RLIMIT_SIGPENDING);
281 		rcu_read_unlock();
282 		qlim = task_rlimit(p, RLIMIT_SIGPENDING);
283 		unlock_task_sighand(p, &flags);
284 	}
285 
286 	seq_put_decimal_ull(m, "Threads:\t", num_threads);
287 	seq_put_decimal_ull(m, "\nSigQ:\t", qsize);
288 	seq_put_decimal_ull(m, "/", qlim);
289 
290 	/* render them all */
291 	render_sigset_t(m, "\nSigPnd:\t", &pending);
292 	render_sigset_t(m, "ShdPnd:\t", &shpending);
293 	render_sigset_t(m, "SigBlk:\t", &blocked);
294 	render_sigset_t(m, "SigIgn:\t", &ignored);
295 	render_sigset_t(m, "SigCgt:\t", &caught);
296 }
297 
298 static void render_cap_t(struct seq_file *m, const char *header,
299 			kernel_cap_t *a)
300 {
301 	unsigned __capi;
302 
303 	seq_puts(m, header);
304 	CAP_FOR_EACH_U32(__capi) {
305 		seq_put_hex_ll(m, NULL,
306 			   a->cap[CAP_LAST_U32 - __capi], 8);
307 	}
308 	seq_putc(m, '\n');
309 }
310 
311 static inline void task_cap(struct seq_file *m, struct task_struct *p)
312 {
313 	const struct cred *cred;
314 	kernel_cap_t cap_inheritable, cap_permitted, cap_effective,
315 			cap_bset, cap_ambient;
316 
317 	rcu_read_lock();
318 	cred = __task_cred(p);
319 	cap_inheritable	= cred->cap_inheritable;
320 	cap_permitted	= cred->cap_permitted;
321 	cap_effective	= cred->cap_effective;
322 	cap_bset	= cred->cap_bset;
323 	cap_ambient	= cred->cap_ambient;
324 	rcu_read_unlock();
325 
326 	render_cap_t(m, "CapInh:\t", &cap_inheritable);
327 	render_cap_t(m, "CapPrm:\t", &cap_permitted);
328 	render_cap_t(m, "CapEff:\t", &cap_effective);
329 	render_cap_t(m, "CapBnd:\t", &cap_bset);
330 	render_cap_t(m, "CapAmb:\t", &cap_ambient);
331 }
332 
333 static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
334 {
335 	seq_put_decimal_ull(m, "NoNewPrivs:\t", task_no_new_privs(p));
336 #ifdef CONFIG_SECCOMP
337 	seq_put_decimal_ull(m, "\nSeccomp:\t", p->seccomp.mode);
338 #ifdef CONFIG_SECCOMP_FILTER
339 	seq_put_decimal_ull(m, "\nSeccomp_filters:\t",
340 			    atomic_read(&p->seccomp.filter_count));
341 #endif
342 #endif
343 	seq_puts(m, "\nSpeculation_Store_Bypass:\t");
344 	switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_STORE_BYPASS)) {
345 	case -EINVAL:
346 		seq_puts(m, "unknown");
347 		break;
348 	case PR_SPEC_NOT_AFFECTED:
349 		seq_puts(m, "not vulnerable");
350 		break;
351 	case PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE:
352 		seq_puts(m, "thread force mitigated");
353 		break;
354 	case PR_SPEC_PRCTL | PR_SPEC_DISABLE:
355 		seq_puts(m, "thread mitigated");
356 		break;
357 	case PR_SPEC_PRCTL | PR_SPEC_ENABLE:
358 		seq_puts(m, "thread vulnerable");
359 		break;
360 	case PR_SPEC_DISABLE:
361 		seq_puts(m, "globally mitigated");
362 		break;
363 	default:
364 		seq_puts(m, "vulnerable");
365 		break;
366 	}
367 
368 	seq_puts(m, "\nSpeculationIndirectBranch:\t");
369 	switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_INDIRECT_BRANCH)) {
370 	case -EINVAL:
371 		seq_puts(m, "unsupported");
372 		break;
373 	case PR_SPEC_NOT_AFFECTED:
374 		seq_puts(m, "not affected");
375 		break;
376 	case PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE:
377 		seq_puts(m, "conditional force disabled");
378 		break;
379 	case PR_SPEC_PRCTL | PR_SPEC_DISABLE:
380 		seq_puts(m, "conditional disabled");
381 		break;
382 	case PR_SPEC_PRCTL | PR_SPEC_ENABLE:
383 		seq_puts(m, "conditional enabled");
384 		break;
385 	case PR_SPEC_ENABLE:
386 		seq_puts(m, "always enabled");
387 		break;
388 	case PR_SPEC_DISABLE:
389 		seq_puts(m, "always disabled");
390 		break;
391 	default:
392 		seq_puts(m, "unknown");
393 		break;
394 	}
395 	seq_putc(m, '\n');
396 }
397 
398 static inline void task_context_switch_counts(struct seq_file *m,
399 						struct task_struct *p)
400 {
401 	seq_put_decimal_ull(m, "voluntary_ctxt_switches:\t", p->nvcsw);
402 	seq_put_decimal_ull(m, "\nnonvoluntary_ctxt_switches:\t", p->nivcsw);
403 	seq_putc(m, '\n');
404 }
405 
406 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
407 {
408 	seq_printf(m, "Cpus_allowed:\t%*pb\n",
409 		   cpumask_pr_args(&task->cpus_mask));
410 	seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
411 		   cpumask_pr_args(&task->cpus_mask));
412 }
413 
414 static inline void task_core_dumping(struct seq_file *m, struct task_struct *task)
415 {
416 	seq_put_decimal_ull(m, "CoreDumping:\t", !!task->signal->core_state);
417 	seq_putc(m, '\n');
418 }
419 
420 static inline void task_thp_status(struct seq_file *m, struct mm_struct *mm)
421 {
422 	bool thp_enabled = IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE);
423 
424 	if (thp_enabled)
425 		thp_enabled = !test_bit(MMF_DISABLE_THP, &mm->flags);
426 	seq_printf(m, "THP_enabled:\t%d\n", thp_enabled);
427 }
428 
429 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
430 			struct pid *pid, struct task_struct *task)
431 {
432 	struct mm_struct *mm = get_task_mm(task);
433 
434 	seq_puts(m, "Name:\t");
435 	proc_task_name(m, task, true);
436 	seq_putc(m, '\n');
437 
438 	task_state(m, ns, pid, task);
439 
440 	if (mm) {
441 		task_mem(m, mm);
442 		task_core_dumping(m, task);
443 		task_thp_status(m, mm);
444 		mmput(mm);
445 	}
446 	task_sig(m, task);
447 	task_cap(m, task);
448 	task_seccomp(m, task);
449 	task_cpus_allowed(m, task);
450 	cpuset_task_status_allowed(m, task);
451 	task_context_switch_counts(m, task);
452 	return 0;
453 }
454 
455 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
456 			struct pid *pid, struct task_struct *task, int whole)
457 {
458 	unsigned long vsize, eip, esp, wchan = 0;
459 	int priority, nice;
460 	int tty_pgrp = -1, tty_nr = 0;
461 	sigset_t sigign, sigcatch;
462 	char state;
463 	pid_t ppid = 0, pgid = -1, sid = -1;
464 	int num_threads = 0;
465 	int permitted;
466 	struct mm_struct *mm;
467 	unsigned long long start_time;
468 	unsigned long cmin_flt = 0, cmaj_flt = 0;
469 	unsigned long  min_flt = 0,  maj_flt = 0;
470 	u64 cutime, cstime, utime, stime;
471 	u64 cgtime, gtime;
472 	unsigned long rsslim = 0;
473 	unsigned long flags;
474 	int exit_code = task->exit_code;
475 
476 	state = *get_task_state(task);
477 	vsize = eip = esp = 0;
478 	permitted = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS | PTRACE_MODE_NOAUDIT);
479 	mm = get_task_mm(task);
480 	if (mm) {
481 		vsize = task_vsize(mm);
482 		/*
483 		 * esp and eip are intentionally zeroed out.  There is no
484 		 * non-racy way to read them without freezing the task.
485 		 * Programs that need reliable values can use ptrace(2).
486 		 *
487 		 * The only exception is if the task is core dumping because
488 		 * a program is not able to use ptrace(2) in that case. It is
489 		 * safe because the task has stopped executing permanently.
490 		 */
491 		if (permitted && (task->flags & (PF_EXITING|PF_DUMPCORE))) {
492 			if (try_get_task_stack(task)) {
493 				eip = KSTK_EIP(task);
494 				esp = KSTK_ESP(task);
495 				put_task_stack(task);
496 			}
497 		}
498 	}
499 
500 	sigemptyset(&sigign);
501 	sigemptyset(&sigcatch);
502 	cutime = cstime = utime = stime = 0;
503 	cgtime = gtime = 0;
504 
505 	if (lock_task_sighand(task, &flags)) {
506 		struct signal_struct *sig = task->signal;
507 
508 		if (sig->tty) {
509 			struct pid *pgrp = tty_get_pgrp(sig->tty);
510 			tty_pgrp = pid_nr_ns(pgrp, ns);
511 			put_pid(pgrp);
512 			tty_nr = new_encode_dev(tty_devnum(sig->tty));
513 		}
514 
515 		num_threads = get_nr_threads(task);
516 		collect_sigign_sigcatch(task, &sigign, &sigcatch);
517 
518 		cmin_flt = sig->cmin_flt;
519 		cmaj_flt = sig->cmaj_flt;
520 		cutime = sig->cutime;
521 		cstime = sig->cstime;
522 		cgtime = sig->cgtime;
523 		rsslim = READ_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
524 
525 		/* add up live thread stats at the group level */
526 		if (whole) {
527 			struct task_struct *t = task;
528 			do {
529 				min_flt += t->min_flt;
530 				maj_flt += t->maj_flt;
531 				gtime += task_gtime(t);
532 			} while_each_thread(task, t);
533 
534 			min_flt += sig->min_flt;
535 			maj_flt += sig->maj_flt;
536 			thread_group_cputime_adjusted(task, &utime, &stime);
537 			gtime += sig->gtime;
538 
539 			if (sig->flags & (SIGNAL_GROUP_EXIT | SIGNAL_STOP_STOPPED))
540 				exit_code = sig->group_exit_code;
541 		}
542 
543 		sid = task_session_nr_ns(task, ns);
544 		ppid = task_tgid_nr_ns(task->real_parent, ns);
545 		pgid = task_pgrp_nr_ns(task, ns);
546 
547 		unlock_task_sighand(task, &flags);
548 	}
549 
550 	if (permitted && (!whole || num_threads < 2))
551 		wchan = !task_is_running(task);
552 	if (!whole) {
553 		min_flt = task->min_flt;
554 		maj_flt = task->maj_flt;
555 		task_cputime_adjusted(task, &utime, &stime);
556 		gtime = task_gtime(task);
557 	}
558 
559 	/* scale priority and nice values from timeslices to -20..20 */
560 	/* to make it look like a "normal" Unix priority/nice value  */
561 	priority = task_prio(task);
562 	nice = task_nice(task);
563 
564 	/* apply timens offset for boottime and convert nsec -> ticks */
565 	start_time =
566 		nsec_to_clock_t(timens_add_boottime_ns(task->start_boottime));
567 
568 	seq_put_decimal_ull(m, "", pid_nr_ns(pid, ns));
569 	seq_puts(m, " (");
570 	proc_task_name(m, task, false);
571 	seq_puts(m, ") ");
572 	seq_putc(m, state);
573 	seq_put_decimal_ll(m, " ", ppid);
574 	seq_put_decimal_ll(m, " ", pgid);
575 	seq_put_decimal_ll(m, " ", sid);
576 	seq_put_decimal_ll(m, " ", tty_nr);
577 	seq_put_decimal_ll(m, " ", tty_pgrp);
578 	seq_put_decimal_ull(m, " ", task->flags);
579 	seq_put_decimal_ull(m, " ", min_flt);
580 	seq_put_decimal_ull(m, " ", cmin_flt);
581 	seq_put_decimal_ull(m, " ", maj_flt);
582 	seq_put_decimal_ull(m, " ", cmaj_flt);
583 	seq_put_decimal_ull(m, " ", nsec_to_clock_t(utime));
584 	seq_put_decimal_ull(m, " ", nsec_to_clock_t(stime));
585 	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cutime));
586 	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cstime));
587 	seq_put_decimal_ll(m, " ", priority);
588 	seq_put_decimal_ll(m, " ", nice);
589 	seq_put_decimal_ll(m, " ", num_threads);
590 	seq_put_decimal_ull(m, " ", 0);
591 	seq_put_decimal_ull(m, " ", start_time);
592 	seq_put_decimal_ull(m, " ", vsize);
593 	seq_put_decimal_ull(m, " ", mm ? get_mm_rss(mm) : 0);
594 	seq_put_decimal_ull(m, " ", rsslim);
595 	seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->start_code : 1) : 0);
596 	seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->end_code : 1) : 0);
597 	seq_put_decimal_ull(m, " ", (permitted && mm) ? mm->start_stack : 0);
598 	seq_put_decimal_ull(m, " ", esp);
599 	seq_put_decimal_ull(m, " ", eip);
600 	/* The signal information here is obsolete.
601 	 * It must be decimal for Linux 2.0 compatibility.
602 	 * Use /proc/#/status for real-time signals.
603 	 */
604 	seq_put_decimal_ull(m, " ", task->pending.signal.sig[0] & 0x7fffffffUL);
605 	seq_put_decimal_ull(m, " ", task->blocked.sig[0] & 0x7fffffffUL);
606 	seq_put_decimal_ull(m, " ", sigign.sig[0] & 0x7fffffffUL);
607 	seq_put_decimal_ull(m, " ", sigcatch.sig[0] & 0x7fffffffUL);
608 
609 	/*
610 	 * We used to output the absolute kernel address, but that's an
611 	 * information leak - so instead we show a 0/1 flag here, to signal
612 	 * to user-space whether there's a wchan field in /proc/PID/wchan.
613 	 *
614 	 * This works with older implementations of procps as well.
615 	 */
616 	seq_put_decimal_ull(m, " ", wchan);
617 
618 	seq_put_decimal_ull(m, " ", 0);
619 	seq_put_decimal_ull(m, " ", 0);
620 	seq_put_decimal_ll(m, " ", task->exit_signal);
621 	seq_put_decimal_ll(m, " ", task_cpu(task));
622 	seq_put_decimal_ull(m, " ", task->rt_priority);
623 	seq_put_decimal_ull(m, " ", task->policy);
624 	seq_put_decimal_ull(m, " ", delayacct_blkio_ticks(task));
625 	seq_put_decimal_ull(m, " ", nsec_to_clock_t(gtime));
626 	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cgtime));
627 
628 	if (mm && permitted) {
629 		seq_put_decimal_ull(m, " ", mm->start_data);
630 		seq_put_decimal_ull(m, " ", mm->end_data);
631 		seq_put_decimal_ull(m, " ", mm->start_brk);
632 		seq_put_decimal_ull(m, " ", mm->arg_start);
633 		seq_put_decimal_ull(m, " ", mm->arg_end);
634 		seq_put_decimal_ull(m, " ", mm->env_start);
635 		seq_put_decimal_ull(m, " ", mm->env_end);
636 	} else
637 		seq_puts(m, " 0 0 0 0 0 0 0");
638 
639 	if (permitted)
640 		seq_put_decimal_ll(m, " ", exit_code);
641 	else
642 		seq_puts(m, " 0");
643 
644 	seq_putc(m, '\n');
645 	if (mm)
646 		mmput(mm);
647 	return 0;
648 }
649 
650 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
651 			struct pid *pid, struct task_struct *task)
652 {
653 	return do_task_stat(m, ns, pid, task, 0);
654 }
655 
656 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
657 			struct pid *pid, struct task_struct *task)
658 {
659 	return do_task_stat(m, ns, pid, task, 1);
660 }
661 
662 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
663 			struct pid *pid, struct task_struct *task)
664 {
665 	struct mm_struct *mm = get_task_mm(task);
666 
667 	if (mm) {
668 		unsigned long size;
669 		unsigned long resident = 0;
670 		unsigned long shared = 0;
671 		unsigned long text = 0;
672 		unsigned long data = 0;
673 
674 		size = task_statm(mm, &shared, &text, &data, &resident);
675 		mmput(mm);
676 
677 		/*
678 		 * For quick read, open code by putting numbers directly
679 		 * expected format is
680 		 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
681 		 *               size, resident, shared, text, data);
682 		 */
683 		seq_put_decimal_ull(m, "", size);
684 		seq_put_decimal_ull(m, " ", resident);
685 		seq_put_decimal_ull(m, " ", shared);
686 		seq_put_decimal_ull(m, " ", text);
687 		seq_put_decimal_ull(m, " ", 0);
688 		seq_put_decimal_ull(m, " ", data);
689 		seq_put_decimal_ull(m, " ", 0);
690 		seq_putc(m, '\n');
691 	} else {
692 		seq_write(m, "0 0 0 0 0 0 0\n", 14);
693 	}
694 	return 0;
695 }
696 
697 #ifdef CONFIG_PROC_CHILDREN
698 static struct pid *
699 get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
700 {
701 	struct task_struct *start, *task;
702 	struct pid *pid = NULL;
703 
704 	read_lock(&tasklist_lock);
705 
706 	start = pid_task(proc_pid(inode), PIDTYPE_PID);
707 	if (!start)
708 		goto out;
709 
710 	/*
711 	 * Lets try to continue searching first, this gives
712 	 * us significant speedup on children-rich processes.
713 	 */
714 	if (pid_prev) {
715 		task = pid_task(pid_prev, PIDTYPE_PID);
716 		if (task && task->real_parent == start &&
717 		    !(list_empty(&task->sibling))) {
718 			if (list_is_last(&task->sibling, &start->children))
719 				goto out;
720 			task = list_first_entry(&task->sibling,
721 						struct task_struct, sibling);
722 			pid = get_pid(task_pid(task));
723 			goto out;
724 		}
725 	}
726 
727 	/*
728 	 * Slow search case.
729 	 *
730 	 * We might miss some children here if children
731 	 * are exited while we were not holding the lock,
732 	 * but it was never promised to be accurate that
733 	 * much.
734 	 *
735 	 * "Just suppose that the parent sleeps, but N children
736 	 *  exit after we printed their tids. Now the slow paths
737 	 *  skips N extra children, we miss N tasks." (c)
738 	 *
739 	 * So one need to stop or freeze the leader and all
740 	 * its children to get a precise result.
741 	 */
742 	list_for_each_entry(task, &start->children, sibling) {
743 		if (pos-- == 0) {
744 			pid = get_pid(task_pid(task));
745 			break;
746 		}
747 	}
748 
749 out:
750 	read_unlock(&tasklist_lock);
751 	return pid;
752 }
753 
754 static int children_seq_show(struct seq_file *seq, void *v)
755 {
756 	struct inode *inode = file_inode(seq->file);
757 
758 	seq_printf(seq, "%d ", pid_nr_ns(v, proc_pid_ns(inode->i_sb)));
759 	return 0;
760 }
761 
762 static void *children_seq_start(struct seq_file *seq, loff_t *pos)
763 {
764 	return get_children_pid(file_inode(seq->file), NULL, *pos);
765 }
766 
767 static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
768 {
769 	struct pid *pid;
770 
771 	pid = get_children_pid(file_inode(seq->file), v, *pos + 1);
772 	put_pid(v);
773 
774 	++*pos;
775 	return pid;
776 }
777 
778 static void children_seq_stop(struct seq_file *seq, void *v)
779 {
780 	put_pid(v);
781 }
782 
783 static const struct seq_operations children_seq_ops = {
784 	.start	= children_seq_start,
785 	.next	= children_seq_next,
786 	.stop	= children_seq_stop,
787 	.show	= children_seq_show,
788 };
789 
790 static int children_seq_open(struct inode *inode, struct file *file)
791 {
792 	return seq_open(file, &children_seq_ops);
793 }
794 
795 const struct file_operations proc_tid_children_operations = {
796 	.open    = children_seq_open,
797 	.read    = seq_read,
798 	.llseek  = seq_lseek,
799 	.release = seq_release,
800 };
801 #endif /* CONFIG_PROC_CHILDREN */
802