1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/proc/base.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 * 7 * proc base directory handling functions 8 * 9 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part. 10 * Instead of using magical inumbers to determine the kind of object 11 * we allocate and fill in-core inodes upon lookup. They don't even 12 * go into icache. We cache the reference to task_struct upon lookup too. 13 * Eventually it should become a filesystem in its own. We don't use the 14 * rest of procfs anymore. 15 * 16 * 17 * Changelog: 18 * 17-Jan-2005 19 * Allan Bezerra 20 * Bruna Moreira <bruna.moreira@indt.org.br> 21 * Edjard Mota <edjard.mota@indt.org.br> 22 * Ilias Biris <ilias.biris@indt.org.br> 23 * Mauricio Lin <mauricio.lin@indt.org.br> 24 * 25 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 26 * 27 * A new process specific entry (smaps) included in /proc. It shows the 28 * size of rss for each memory area. The maps entry lacks information 29 * about physical memory size (rss) for each mapped file, i.e., 30 * rss information for executables and library files. 31 * This additional information is useful for any tools that need to know 32 * about physical memory consumption for a process specific library. 33 * 34 * Changelog: 35 * 21-Feb-2005 36 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 37 * Pud inclusion in the page table walking. 38 * 39 * ChangeLog: 40 * 10-Mar-2005 41 * 10LE Instituto Nokia de Tecnologia - INdT: 42 * A better way to walks through the page table as suggested by Hugh Dickins. 43 * 44 * Simo Piiroinen <simo.piiroinen@nokia.com>: 45 * Smaps information related to shared, private, clean and dirty pages. 46 * 47 * Paul Mundt <paul.mundt@nokia.com>: 48 * Overall revision about smaps. 49 */ 50 51 #include <linux/uaccess.h> 52 53 #include <linux/errno.h> 54 #include <linux/time.h> 55 #include <linux/proc_fs.h> 56 #include <linux/stat.h> 57 #include <linux/task_io_accounting_ops.h> 58 #include <linux/init.h> 59 #include <linux/capability.h> 60 #include <linux/file.h> 61 #include <linux/fdtable.h> 62 #include <linux/string.h> 63 #include <linux/seq_file.h> 64 #include <linux/namei.h> 65 #include <linux/mnt_namespace.h> 66 #include <linux/mm.h> 67 #include <linux/swap.h> 68 #include <linux/rcupdate.h> 69 #include <linux/kallsyms.h> 70 #include <linux/stacktrace.h> 71 #include <linux/resource.h> 72 #include <linux/module.h> 73 #include <linux/mount.h> 74 #include <linux/security.h> 75 #include <linux/ptrace.h> 76 #include <linux/tracehook.h> 77 #include <linux/printk.h> 78 #include <linux/cache.h> 79 #include <linux/cgroup.h> 80 #include <linux/cpuset.h> 81 #include <linux/audit.h> 82 #include <linux/poll.h> 83 #include <linux/nsproxy.h> 84 #include <linux/oom.h> 85 #include <linux/elf.h> 86 #include <linux/pid_namespace.h> 87 #include <linux/user_namespace.h> 88 #include <linux/fs_struct.h> 89 #include <linux/slab.h> 90 #include <linux/sched/autogroup.h> 91 #include <linux/sched/mm.h> 92 #include <linux/sched/coredump.h> 93 #include <linux/sched/debug.h> 94 #include <linux/sched/stat.h> 95 #include <linux/flex_array.h> 96 #include <linux/posix-timers.h> 97 #include <trace/events/oom.h> 98 #include "internal.h" 99 #include "fd.h" 100 101 #include "../../lib/kstrtox.h" 102 103 /* NOTE: 104 * Implementing inode permission operations in /proc is almost 105 * certainly an error. Permission checks need to happen during 106 * each system call not at open time. The reason is that most of 107 * what we wish to check for permissions in /proc varies at runtime. 108 * 109 * The classic example of a problem is opening file descriptors 110 * in /proc for a task before it execs a suid executable. 111 */ 112 113 static u8 nlink_tid __ro_after_init; 114 static u8 nlink_tgid __ro_after_init; 115 116 struct pid_entry { 117 const char *name; 118 unsigned int len; 119 umode_t mode; 120 const struct inode_operations *iop; 121 const struct file_operations *fop; 122 union proc_op op; 123 }; 124 125 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 126 .name = (NAME), \ 127 .len = sizeof(NAME) - 1, \ 128 .mode = MODE, \ 129 .iop = IOP, \ 130 .fop = FOP, \ 131 .op = OP, \ 132 } 133 134 #define DIR(NAME, MODE, iops, fops) \ 135 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 136 #define LNK(NAME, get_link) \ 137 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 138 &proc_pid_link_inode_operations, NULL, \ 139 { .proc_get_link = get_link } ) 140 #define REG(NAME, MODE, fops) \ 141 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 142 #define ONE(NAME, MODE, show) \ 143 NOD(NAME, (S_IFREG|(MODE)), \ 144 NULL, &proc_single_file_operations, \ 145 { .proc_show = show } ) 146 147 /* 148 * Count the number of hardlinks for the pid_entry table, excluding the . 149 * and .. links. 150 */ 151 static unsigned int __init pid_entry_nlink(const struct pid_entry *entries, 152 unsigned int n) 153 { 154 unsigned int i; 155 unsigned int count; 156 157 count = 2; 158 for (i = 0; i < n; ++i) { 159 if (S_ISDIR(entries[i].mode)) 160 ++count; 161 } 162 163 return count; 164 } 165 166 static int get_task_root(struct task_struct *task, struct path *root) 167 { 168 int result = -ENOENT; 169 170 task_lock(task); 171 if (task->fs) { 172 get_fs_root(task->fs, root); 173 result = 0; 174 } 175 task_unlock(task); 176 return result; 177 } 178 179 static int proc_cwd_link(struct dentry *dentry, struct path *path) 180 { 181 struct task_struct *task = get_proc_task(d_inode(dentry)); 182 int result = -ENOENT; 183 184 if (task) { 185 task_lock(task); 186 if (task->fs) { 187 get_fs_pwd(task->fs, path); 188 result = 0; 189 } 190 task_unlock(task); 191 put_task_struct(task); 192 } 193 return result; 194 } 195 196 static int proc_root_link(struct dentry *dentry, struct path *path) 197 { 198 struct task_struct *task = get_proc_task(d_inode(dentry)); 199 int result = -ENOENT; 200 201 if (task) { 202 result = get_task_root(task, path); 203 put_task_struct(task); 204 } 205 return result; 206 } 207 208 static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf, 209 size_t count, loff_t *ppos) 210 { 211 unsigned long arg_start, arg_end, env_start, env_end; 212 unsigned long pos, len; 213 char *page; 214 215 /* Check if process spawned far enough to have cmdline. */ 216 if (!mm->env_end) 217 return 0; 218 219 spin_lock(&mm->arg_lock); 220 arg_start = mm->arg_start; 221 arg_end = mm->arg_end; 222 env_start = mm->env_start; 223 env_end = mm->env_end; 224 spin_unlock(&mm->arg_lock); 225 226 if (arg_start >= arg_end) 227 return 0; 228 229 /* 230 * We have traditionally allowed the user to re-write 231 * the argument strings and overflow the end result 232 * into the environment section. But only do that if 233 * the environment area is contiguous to the arguments. 234 */ 235 if (env_start != arg_end || env_start >= env_end) 236 env_start = env_end = arg_end; 237 238 /* .. and limit it to a maximum of one page of slop */ 239 if (env_end >= arg_end + PAGE_SIZE) 240 env_end = arg_end + PAGE_SIZE - 1; 241 242 /* We're not going to care if "*ppos" has high bits set */ 243 pos = arg_start + *ppos; 244 245 /* .. but we do check the result is in the proper range */ 246 if (pos < arg_start || pos >= env_end) 247 return 0; 248 249 /* .. and we never go past env_end */ 250 if (env_end - pos < count) 251 count = env_end - pos; 252 253 page = (char *)__get_free_page(GFP_KERNEL); 254 if (!page) 255 return -ENOMEM; 256 257 len = 0; 258 while (count) { 259 int got; 260 size_t size = min_t(size_t, PAGE_SIZE, count); 261 long offset; 262 263 /* 264 * Are we already starting past the official end? 265 * We always include the last byte that is *supposed* 266 * to be NUL 267 */ 268 offset = (pos >= arg_end) ? pos - arg_end + 1 : 0; 269 270 got = access_remote_vm(mm, pos - offset, page, size + offset, FOLL_ANON); 271 if (got <= offset) 272 break; 273 got -= offset; 274 275 /* Don't walk past a NUL character once you hit arg_end */ 276 if (pos + got >= arg_end) { 277 int n = 0; 278 279 /* 280 * If we started before 'arg_end' but ended up 281 * at or after it, we start the NUL character 282 * check at arg_end-1 (where we expect the normal 283 * EOF to be). 284 * 285 * NOTE! This is smaller than 'got', because 286 * pos + got >= arg_end 287 */ 288 if (pos < arg_end) 289 n = arg_end - pos - 1; 290 291 /* Cut off at first NUL after 'n' */ 292 got = n + strnlen(page+n, offset+got-n); 293 if (got < offset) 294 break; 295 got -= offset; 296 297 /* Include the NUL if it existed */ 298 if (got < size) 299 got++; 300 } 301 302 got -= copy_to_user(buf, page+offset, got); 303 if (unlikely(!got)) { 304 if (!len) 305 len = -EFAULT; 306 break; 307 } 308 pos += got; 309 buf += got; 310 len += got; 311 count -= got; 312 } 313 314 free_page((unsigned long)page); 315 return len; 316 } 317 318 static ssize_t get_task_cmdline(struct task_struct *tsk, char __user *buf, 319 size_t count, loff_t *pos) 320 { 321 struct mm_struct *mm; 322 ssize_t ret; 323 324 mm = get_task_mm(tsk); 325 if (!mm) 326 return 0; 327 328 ret = get_mm_cmdline(mm, buf, count, pos); 329 mmput(mm); 330 return ret; 331 } 332 333 static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf, 334 size_t count, loff_t *pos) 335 { 336 struct task_struct *tsk; 337 ssize_t ret; 338 339 BUG_ON(*pos < 0); 340 341 tsk = get_proc_task(file_inode(file)); 342 if (!tsk) 343 return -ESRCH; 344 ret = get_task_cmdline(tsk, buf, count, pos); 345 put_task_struct(tsk); 346 if (ret > 0) 347 *pos += ret; 348 return ret; 349 } 350 351 static const struct file_operations proc_pid_cmdline_ops = { 352 .read = proc_pid_cmdline_read, 353 .llseek = generic_file_llseek, 354 }; 355 356 #ifdef CONFIG_KALLSYMS 357 /* 358 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 359 * Returns the resolved symbol. If that fails, simply return the address. 360 */ 361 static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, 362 struct pid *pid, struct task_struct *task) 363 { 364 unsigned long wchan; 365 char symname[KSYM_NAME_LEN]; 366 367 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 368 goto print0; 369 370 wchan = get_wchan(task); 371 if (wchan && !lookup_symbol_name(wchan, symname)) { 372 seq_puts(m, symname); 373 return 0; 374 } 375 376 print0: 377 seq_putc(m, '0'); 378 return 0; 379 } 380 #endif /* CONFIG_KALLSYMS */ 381 382 static int lock_trace(struct task_struct *task) 383 { 384 int err = mutex_lock_killable(&task->signal->cred_guard_mutex); 385 if (err) 386 return err; 387 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) { 388 mutex_unlock(&task->signal->cred_guard_mutex); 389 return -EPERM; 390 } 391 return 0; 392 } 393 394 static void unlock_trace(struct task_struct *task) 395 { 396 mutex_unlock(&task->signal->cred_guard_mutex); 397 } 398 399 #ifdef CONFIG_STACKTRACE 400 401 #define MAX_STACK_TRACE_DEPTH 64 402 403 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 404 struct pid *pid, struct task_struct *task) 405 { 406 struct stack_trace trace; 407 unsigned long *entries; 408 int err; 409 410 /* 411 * The ability to racily run the kernel stack unwinder on a running task 412 * and then observe the unwinder output is scary; while it is useful for 413 * debugging kernel issues, it can also allow an attacker to leak kernel 414 * stack contents. 415 * Doing this in a manner that is at least safe from races would require 416 * some work to ensure that the remote task can not be scheduled; and 417 * even then, this would still expose the unwinder as local attack 418 * surface. 419 * Therefore, this interface is restricted to root. 420 */ 421 if (!file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN)) 422 return -EACCES; 423 424 entries = kmalloc_array(MAX_STACK_TRACE_DEPTH, sizeof(*entries), 425 GFP_KERNEL); 426 if (!entries) 427 return -ENOMEM; 428 429 trace.nr_entries = 0; 430 trace.max_entries = MAX_STACK_TRACE_DEPTH; 431 trace.entries = entries; 432 trace.skip = 0; 433 434 err = lock_trace(task); 435 if (!err) { 436 unsigned int i; 437 438 save_stack_trace_tsk(task, &trace); 439 440 for (i = 0; i < trace.nr_entries; i++) { 441 seq_printf(m, "[<0>] %pB\n", (void *)entries[i]); 442 } 443 unlock_trace(task); 444 } 445 kfree(entries); 446 447 return err; 448 } 449 #endif 450 451 #ifdef CONFIG_SCHED_INFO 452 /* 453 * Provides /proc/PID/schedstat 454 */ 455 static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, 456 struct pid *pid, struct task_struct *task) 457 { 458 if (unlikely(!sched_info_on())) 459 seq_printf(m, "0 0 0\n"); 460 else 461 seq_printf(m, "%llu %llu %lu\n", 462 (unsigned long long)task->se.sum_exec_runtime, 463 (unsigned long long)task->sched_info.run_delay, 464 task->sched_info.pcount); 465 466 return 0; 467 } 468 #endif 469 470 #ifdef CONFIG_LATENCYTOP 471 static int lstats_show_proc(struct seq_file *m, void *v) 472 { 473 int i; 474 struct inode *inode = m->private; 475 struct task_struct *task = get_proc_task(inode); 476 477 if (!task) 478 return -ESRCH; 479 seq_puts(m, "Latency Top version : v0.1\n"); 480 for (i = 0; i < LT_SAVECOUNT; i++) { 481 struct latency_record *lr = &task->latency_record[i]; 482 if (lr->backtrace[0]) { 483 int q; 484 seq_printf(m, "%i %li %li", 485 lr->count, lr->time, lr->max); 486 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 487 unsigned long bt = lr->backtrace[q]; 488 if (!bt) 489 break; 490 if (bt == ULONG_MAX) 491 break; 492 seq_printf(m, " %ps", (void *)bt); 493 } 494 seq_putc(m, '\n'); 495 } 496 497 } 498 put_task_struct(task); 499 return 0; 500 } 501 502 static int lstats_open(struct inode *inode, struct file *file) 503 { 504 return single_open(file, lstats_show_proc, inode); 505 } 506 507 static ssize_t lstats_write(struct file *file, const char __user *buf, 508 size_t count, loff_t *offs) 509 { 510 struct task_struct *task = get_proc_task(file_inode(file)); 511 512 if (!task) 513 return -ESRCH; 514 clear_all_latency_tracing(task); 515 put_task_struct(task); 516 517 return count; 518 } 519 520 static const struct file_operations proc_lstats_operations = { 521 .open = lstats_open, 522 .read = seq_read, 523 .write = lstats_write, 524 .llseek = seq_lseek, 525 .release = single_release, 526 }; 527 528 #endif 529 530 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, 531 struct pid *pid, struct task_struct *task) 532 { 533 unsigned long totalpages = totalram_pages + total_swap_pages; 534 unsigned long points = 0; 535 536 points = oom_badness(task, NULL, NULL, totalpages) * 537 1000 / totalpages; 538 seq_printf(m, "%lu\n", points); 539 540 return 0; 541 } 542 543 struct limit_names { 544 const char *name; 545 const char *unit; 546 }; 547 548 static const struct limit_names lnames[RLIM_NLIMITS] = { 549 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 550 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 551 [RLIMIT_DATA] = {"Max data size", "bytes"}, 552 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 553 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 554 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 555 [RLIMIT_NPROC] = {"Max processes", "processes"}, 556 [RLIMIT_NOFILE] = {"Max open files", "files"}, 557 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 558 [RLIMIT_AS] = {"Max address space", "bytes"}, 559 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 560 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 561 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 562 [RLIMIT_NICE] = {"Max nice priority", NULL}, 563 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 564 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 565 }; 566 567 /* Display limits for a process */ 568 static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns, 569 struct pid *pid, struct task_struct *task) 570 { 571 unsigned int i; 572 unsigned long flags; 573 574 struct rlimit rlim[RLIM_NLIMITS]; 575 576 if (!lock_task_sighand(task, &flags)) 577 return 0; 578 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 579 unlock_task_sighand(task, &flags); 580 581 /* 582 * print the file header 583 */ 584 seq_printf(m, "%-25s %-20s %-20s %-10s\n", 585 "Limit", "Soft Limit", "Hard Limit", "Units"); 586 587 for (i = 0; i < RLIM_NLIMITS; i++) { 588 if (rlim[i].rlim_cur == RLIM_INFINITY) 589 seq_printf(m, "%-25s %-20s ", 590 lnames[i].name, "unlimited"); 591 else 592 seq_printf(m, "%-25s %-20lu ", 593 lnames[i].name, rlim[i].rlim_cur); 594 595 if (rlim[i].rlim_max == RLIM_INFINITY) 596 seq_printf(m, "%-20s ", "unlimited"); 597 else 598 seq_printf(m, "%-20lu ", rlim[i].rlim_max); 599 600 if (lnames[i].unit) 601 seq_printf(m, "%-10s\n", lnames[i].unit); 602 else 603 seq_putc(m, '\n'); 604 } 605 606 return 0; 607 } 608 609 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 610 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, 611 struct pid *pid, struct task_struct *task) 612 { 613 long nr; 614 unsigned long args[6], sp, pc; 615 int res; 616 617 res = lock_trace(task); 618 if (res) 619 return res; 620 621 if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) 622 seq_puts(m, "running\n"); 623 else if (nr < 0) 624 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc); 625 else 626 seq_printf(m, 627 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 628 nr, 629 args[0], args[1], args[2], args[3], args[4], args[5], 630 sp, pc); 631 unlock_trace(task); 632 633 return 0; 634 } 635 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 636 637 /************************************************************************/ 638 /* Here the fs part begins */ 639 /************************************************************************/ 640 641 /* permission checks */ 642 static int proc_fd_access_allowed(struct inode *inode) 643 { 644 struct task_struct *task; 645 int allowed = 0; 646 /* Allow access to a task's file descriptors if it is us or we 647 * may use ptrace attach to the process and find out that 648 * information. 649 */ 650 task = get_proc_task(inode); 651 if (task) { 652 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 653 put_task_struct(task); 654 } 655 return allowed; 656 } 657 658 int proc_setattr(struct dentry *dentry, struct iattr *attr) 659 { 660 int error; 661 struct inode *inode = d_inode(dentry); 662 663 if (attr->ia_valid & ATTR_MODE) 664 return -EPERM; 665 666 error = setattr_prepare(dentry, attr); 667 if (error) 668 return error; 669 670 setattr_copy(inode, attr); 671 mark_inode_dirty(inode); 672 return 0; 673 } 674 675 /* 676 * May current process learn task's sched/cmdline info (for hide_pid_min=1) 677 * or euid/egid (for hide_pid_min=2)? 678 */ 679 static bool has_pid_permissions(struct pid_namespace *pid, 680 struct task_struct *task, 681 int hide_pid_min) 682 { 683 if (pid->hide_pid < hide_pid_min) 684 return true; 685 if (in_group_p(pid->pid_gid)) 686 return true; 687 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 688 } 689 690 691 static int proc_pid_permission(struct inode *inode, int mask) 692 { 693 struct pid_namespace *pid = proc_pid_ns(inode); 694 struct task_struct *task; 695 bool has_perms; 696 697 task = get_proc_task(inode); 698 if (!task) 699 return -ESRCH; 700 has_perms = has_pid_permissions(pid, task, HIDEPID_NO_ACCESS); 701 put_task_struct(task); 702 703 if (!has_perms) { 704 if (pid->hide_pid == HIDEPID_INVISIBLE) { 705 /* 706 * Let's make getdents(), stat(), and open() 707 * consistent with each other. If a process 708 * may not stat() a file, it shouldn't be seen 709 * in procfs at all. 710 */ 711 return -ENOENT; 712 } 713 714 return -EPERM; 715 } 716 return generic_permission(inode, mask); 717 } 718 719 720 721 static const struct inode_operations proc_def_inode_operations = { 722 .setattr = proc_setattr, 723 }; 724 725 static int proc_single_show(struct seq_file *m, void *v) 726 { 727 struct inode *inode = m->private; 728 struct pid_namespace *ns = proc_pid_ns(inode); 729 struct pid *pid = proc_pid(inode); 730 struct task_struct *task; 731 int ret; 732 733 task = get_pid_task(pid, PIDTYPE_PID); 734 if (!task) 735 return -ESRCH; 736 737 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 738 739 put_task_struct(task); 740 return ret; 741 } 742 743 static int proc_single_open(struct inode *inode, struct file *filp) 744 { 745 return single_open(filp, proc_single_show, inode); 746 } 747 748 static const struct file_operations proc_single_file_operations = { 749 .open = proc_single_open, 750 .read = seq_read, 751 .llseek = seq_lseek, 752 .release = single_release, 753 }; 754 755 756 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) 757 { 758 struct task_struct *task = get_proc_task(inode); 759 struct mm_struct *mm = ERR_PTR(-ESRCH); 760 761 if (task) { 762 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS); 763 put_task_struct(task); 764 765 if (!IS_ERR_OR_NULL(mm)) { 766 /* ensure this mm_struct can't be freed */ 767 mmgrab(mm); 768 /* but do not pin its memory */ 769 mmput(mm); 770 } 771 } 772 773 return mm; 774 } 775 776 static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) 777 { 778 struct mm_struct *mm = proc_mem_open(inode, mode); 779 780 if (IS_ERR(mm)) 781 return PTR_ERR(mm); 782 783 file->private_data = mm; 784 return 0; 785 } 786 787 static int mem_open(struct inode *inode, struct file *file) 788 { 789 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH); 790 791 /* OK to pass negative loff_t, we can catch out-of-range */ 792 file->f_mode |= FMODE_UNSIGNED_OFFSET; 793 794 return ret; 795 } 796 797 static ssize_t mem_rw(struct file *file, char __user *buf, 798 size_t count, loff_t *ppos, int write) 799 { 800 struct mm_struct *mm = file->private_data; 801 unsigned long addr = *ppos; 802 ssize_t copied; 803 char *page; 804 unsigned int flags; 805 806 if (!mm) 807 return 0; 808 809 page = (char *)__get_free_page(GFP_KERNEL); 810 if (!page) 811 return -ENOMEM; 812 813 copied = 0; 814 if (!mmget_not_zero(mm)) 815 goto free; 816 817 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0); 818 819 while (count > 0) { 820 int this_len = min_t(int, count, PAGE_SIZE); 821 822 if (write && copy_from_user(page, buf, this_len)) { 823 copied = -EFAULT; 824 break; 825 } 826 827 this_len = access_remote_vm(mm, addr, page, this_len, flags); 828 if (!this_len) { 829 if (!copied) 830 copied = -EIO; 831 break; 832 } 833 834 if (!write && copy_to_user(buf, page, this_len)) { 835 copied = -EFAULT; 836 break; 837 } 838 839 buf += this_len; 840 addr += this_len; 841 copied += this_len; 842 count -= this_len; 843 } 844 *ppos = addr; 845 846 mmput(mm); 847 free: 848 free_page((unsigned long) page); 849 return copied; 850 } 851 852 static ssize_t mem_read(struct file *file, char __user *buf, 853 size_t count, loff_t *ppos) 854 { 855 return mem_rw(file, buf, count, ppos, 0); 856 } 857 858 static ssize_t mem_write(struct file *file, const char __user *buf, 859 size_t count, loff_t *ppos) 860 { 861 return mem_rw(file, (char __user*)buf, count, ppos, 1); 862 } 863 864 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 865 { 866 switch (orig) { 867 case 0: 868 file->f_pos = offset; 869 break; 870 case 1: 871 file->f_pos += offset; 872 break; 873 default: 874 return -EINVAL; 875 } 876 force_successful_syscall_return(); 877 return file->f_pos; 878 } 879 880 static int mem_release(struct inode *inode, struct file *file) 881 { 882 struct mm_struct *mm = file->private_data; 883 if (mm) 884 mmdrop(mm); 885 return 0; 886 } 887 888 static const struct file_operations proc_mem_operations = { 889 .llseek = mem_lseek, 890 .read = mem_read, 891 .write = mem_write, 892 .open = mem_open, 893 .release = mem_release, 894 }; 895 896 static int environ_open(struct inode *inode, struct file *file) 897 { 898 return __mem_open(inode, file, PTRACE_MODE_READ); 899 } 900 901 static ssize_t environ_read(struct file *file, char __user *buf, 902 size_t count, loff_t *ppos) 903 { 904 char *page; 905 unsigned long src = *ppos; 906 int ret = 0; 907 struct mm_struct *mm = file->private_data; 908 unsigned long env_start, env_end; 909 910 /* Ensure the process spawned far enough to have an environment. */ 911 if (!mm || !mm->env_end) 912 return 0; 913 914 page = (char *)__get_free_page(GFP_KERNEL); 915 if (!page) 916 return -ENOMEM; 917 918 ret = 0; 919 if (!mmget_not_zero(mm)) 920 goto free; 921 922 spin_lock(&mm->arg_lock); 923 env_start = mm->env_start; 924 env_end = mm->env_end; 925 spin_unlock(&mm->arg_lock); 926 927 while (count > 0) { 928 size_t this_len, max_len; 929 int retval; 930 931 if (src >= (env_end - env_start)) 932 break; 933 934 this_len = env_end - (env_start + src); 935 936 max_len = min_t(size_t, PAGE_SIZE, count); 937 this_len = min(max_len, this_len); 938 939 retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON); 940 941 if (retval <= 0) { 942 ret = retval; 943 break; 944 } 945 946 if (copy_to_user(buf, page, retval)) { 947 ret = -EFAULT; 948 break; 949 } 950 951 ret += retval; 952 src += retval; 953 buf += retval; 954 count -= retval; 955 } 956 *ppos = src; 957 mmput(mm); 958 959 free: 960 free_page((unsigned long) page); 961 return ret; 962 } 963 964 static const struct file_operations proc_environ_operations = { 965 .open = environ_open, 966 .read = environ_read, 967 .llseek = generic_file_llseek, 968 .release = mem_release, 969 }; 970 971 static int auxv_open(struct inode *inode, struct file *file) 972 { 973 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); 974 } 975 976 static ssize_t auxv_read(struct file *file, char __user *buf, 977 size_t count, loff_t *ppos) 978 { 979 struct mm_struct *mm = file->private_data; 980 unsigned int nwords = 0; 981 982 if (!mm) 983 return 0; 984 do { 985 nwords += 2; 986 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 987 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv, 988 nwords * sizeof(mm->saved_auxv[0])); 989 } 990 991 static const struct file_operations proc_auxv_operations = { 992 .open = auxv_open, 993 .read = auxv_read, 994 .llseek = generic_file_llseek, 995 .release = mem_release, 996 }; 997 998 static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, 999 loff_t *ppos) 1000 { 1001 struct task_struct *task = get_proc_task(file_inode(file)); 1002 char buffer[PROC_NUMBUF]; 1003 int oom_adj = OOM_ADJUST_MIN; 1004 size_t len; 1005 1006 if (!task) 1007 return -ESRCH; 1008 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) 1009 oom_adj = OOM_ADJUST_MAX; 1010 else 1011 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / 1012 OOM_SCORE_ADJ_MAX; 1013 put_task_struct(task); 1014 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj); 1015 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1016 } 1017 1018 static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) 1019 { 1020 static DEFINE_MUTEX(oom_adj_mutex); 1021 struct mm_struct *mm = NULL; 1022 struct task_struct *task; 1023 int err = 0; 1024 1025 task = get_proc_task(file_inode(file)); 1026 if (!task) 1027 return -ESRCH; 1028 1029 mutex_lock(&oom_adj_mutex); 1030 if (legacy) { 1031 if (oom_adj < task->signal->oom_score_adj && 1032 !capable(CAP_SYS_RESOURCE)) { 1033 err = -EACCES; 1034 goto err_unlock; 1035 } 1036 /* 1037 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use 1038 * /proc/pid/oom_score_adj instead. 1039 */ 1040 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", 1041 current->comm, task_pid_nr(current), task_pid_nr(task), 1042 task_pid_nr(task)); 1043 } else { 1044 if ((short)oom_adj < task->signal->oom_score_adj_min && 1045 !capable(CAP_SYS_RESOURCE)) { 1046 err = -EACCES; 1047 goto err_unlock; 1048 } 1049 } 1050 1051 /* 1052 * Make sure we will check other processes sharing the mm if this is 1053 * not vfrok which wants its own oom_score_adj. 1054 * pin the mm so it doesn't go away and get reused after task_unlock 1055 */ 1056 if (!task->vfork_done) { 1057 struct task_struct *p = find_lock_task_mm(task); 1058 1059 if (p) { 1060 if (atomic_read(&p->mm->mm_users) > 1) { 1061 mm = p->mm; 1062 mmgrab(mm); 1063 } 1064 task_unlock(p); 1065 } 1066 } 1067 1068 task->signal->oom_score_adj = oom_adj; 1069 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1070 task->signal->oom_score_adj_min = (short)oom_adj; 1071 trace_oom_score_adj_update(task); 1072 1073 if (mm) { 1074 struct task_struct *p; 1075 1076 rcu_read_lock(); 1077 for_each_process(p) { 1078 if (same_thread_group(task, p)) 1079 continue; 1080 1081 /* do not touch kernel threads or the global init */ 1082 if (p->flags & PF_KTHREAD || is_global_init(p)) 1083 continue; 1084 1085 task_lock(p); 1086 if (!p->vfork_done && process_shares_mm(p, mm)) { 1087 pr_info("updating oom_score_adj for %d (%s) from %d to %d because it shares mm with %d (%s). Report if this is unexpected.\n", 1088 task_pid_nr(p), p->comm, 1089 p->signal->oom_score_adj, oom_adj, 1090 task_pid_nr(task), task->comm); 1091 p->signal->oom_score_adj = oom_adj; 1092 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1093 p->signal->oom_score_adj_min = (short)oom_adj; 1094 } 1095 task_unlock(p); 1096 } 1097 rcu_read_unlock(); 1098 mmdrop(mm); 1099 } 1100 err_unlock: 1101 mutex_unlock(&oom_adj_mutex); 1102 put_task_struct(task); 1103 return err; 1104 } 1105 1106 /* 1107 * /proc/pid/oom_adj exists solely for backwards compatibility with previous 1108 * kernels. The effective policy is defined by oom_score_adj, which has a 1109 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly. 1110 * Values written to oom_adj are simply mapped linearly to oom_score_adj. 1111 * Processes that become oom disabled via oom_adj will still be oom disabled 1112 * with this implementation. 1113 * 1114 * oom_adj cannot be removed since existing userspace binaries use it. 1115 */ 1116 static ssize_t oom_adj_write(struct file *file, const char __user *buf, 1117 size_t count, loff_t *ppos) 1118 { 1119 char buffer[PROC_NUMBUF]; 1120 int oom_adj; 1121 int err; 1122 1123 memset(buffer, 0, sizeof(buffer)); 1124 if (count > sizeof(buffer) - 1) 1125 count = sizeof(buffer) - 1; 1126 if (copy_from_user(buffer, buf, count)) { 1127 err = -EFAULT; 1128 goto out; 1129 } 1130 1131 err = kstrtoint(strstrip(buffer), 0, &oom_adj); 1132 if (err) 1133 goto out; 1134 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && 1135 oom_adj != OOM_DISABLE) { 1136 err = -EINVAL; 1137 goto out; 1138 } 1139 1140 /* 1141 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum 1142 * value is always attainable. 1143 */ 1144 if (oom_adj == OOM_ADJUST_MAX) 1145 oom_adj = OOM_SCORE_ADJ_MAX; 1146 else 1147 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; 1148 1149 err = __set_oom_adj(file, oom_adj, true); 1150 out: 1151 return err < 0 ? err : count; 1152 } 1153 1154 static const struct file_operations proc_oom_adj_operations = { 1155 .read = oom_adj_read, 1156 .write = oom_adj_write, 1157 .llseek = generic_file_llseek, 1158 }; 1159 1160 static ssize_t oom_score_adj_read(struct file *file, char __user *buf, 1161 size_t count, loff_t *ppos) 1162 { 1163 struct task_struct *task = get_proc_task(file_inode(file)); 1164 char buffer[PROC_NUMBUF]; 1165 short oom_score_adj = OOM_SCORE_ADJ_MIN; 1166 size_t len; 1167 1168 if (!task) 1169 return -ESRCH; 1170 oom_score_adj = task->signal->oom_score_adj; 1171 put_task_struct(task); 1172 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj); 1173 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1174 } 1175 1176 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, 1177 size_t count, loff_t *ppos) 1178 { 1179 char buffer[PROC_NUMBUF]; 1180 int oom_score_adj; 1181 int err; 1182 1183 memset(buffer, 0, sizeof(buffer)); 1184 if (count > sizeof(buffer) - 1) 1185 count = sizeof(buffer) - 1; 1186 if (copy_from_user(buffer, buf, count)) { 1187 err = -EFAULT; 1188 goto out; 1189 } 1190 1191 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj); 1192 if (err) 1193 goto out; 1194 if (oom_score_adj < OOM_SCORE_ADJ_MIN || 1195 oom_score_adj > OOM_SCORE_ADJ_MAX) { 1196 err = -EINVAL; 1197 goto out; 1198 } 1199 1200 err = __set_oom_adj(file, oom_score_adj, false); 1201 out: 1202 return err < 0 ? err : count; 1203 } 1204 1205 static const struct file_operations proc_oom_score_adj_operations = { 1206 .read = oom_score_adj_read, 1207 .write = oom_score_adj_write, 1208 .llseek = default_llseek, 1209 }; 1210 1211 #ifdef CONFIG_AUDITSYSCALL 1212 #define TMPBUFLEN 11 1213 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1214 size_t count, loff_t *ppos) 1215 { 1216 struct inode * inode = file_inode(file); 1217 struct task_struct *task = get_proc_task(inode); 1218 ssize_t length; 1219 char tmpbuf[TMPBUFLEN]; 1220 1221 if (!task) 1222 return -ESRCH; 1223 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1224 from_kuid(file->f_cred->user_ns, 1225 audit_get_loginuid(task))); 1226 put_task_struct(task); 1227 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1228 } 1229 1230 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1231 size_t count, loff_t *ppos) 1232 { 1233 struct inode * inode = file_inode(file); 1234 uid_t loginuid; 1235 kuid_t kloginuid; 1236 int rv; 1237 1238 rcu_read_lock(); 1239 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 1240 rcu_read_unlock(); 1241 return -EPERM; 1242 } 1243 rcu_read_unlock(); 1244 1245 if (*ppos != 0) { 1246 /* No partial writes. */ 1247 return -EINVAL; 1248 } 1249 1250 rv = kstrtou32_from_user(buf, count, 10, &loginuid); 1251 if (rv < 0) 1252 return rv; 1253 1254 /* is userspace tring to explicitly UNSET the loginuid? */ 1255 if (loginuid == AUDIT_UID_UNSET) { 1256 kloginuid = INVALID_UID; 1257 } else { 1258 kloginuid = make_kuid(file->f_cred->user_ns, loginuid); 1259 if (!uid_valid(kloginuid)) 1260 return -EINVAL; 1261 } 1262 1263 rv = audit_set_loginuid(kloginuid); 1264 if (rv < 0) 1265 return rv; 1266 return count; 1267 } 1268 1269 static const struct file_operations proc_loginuid_operations = { 1270 .read = proc_loginuid_read, 1271 .write = proc_loginuid_write, 1272 .llseek = generic_file_llseek, 1273 }; 1274 1275 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1276 size_t count, loff_t *ppos) 1277 { 1278 struct inode * inode = file_inode(file); 1279 struct task_struct *task = get_proc_task(inode); 1280 ssize_t length; 1281 char tmpbuf[TMPBUFLEN]; 1282 1283 if (!task) 1284 return -ESRCH; 1285 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1286 audit_get_sessionid(task)); 1287 put_task_struct(task); 1288 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1289 } 1290 1291 static const struct file_operations proc_sessionid_operations = { 1292 .read = proc_sessionid_read, 1293 .llseek = generic_file_llseek, 1294 }; 1295 #endif 1296 1297 #ifdef CONFIG_FAULT_INJECTION 1298 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1299 size_t count, loff_t *ppos) 1300 { 1301 struct task_struct *task = get_proc_task(file_inode(file)); 1302 char buffer[PROC_NUMBUF]; 1303 size_t len; 1304 int make_it_fail; 1305 1306 if (!task) 1307 return -ESRCH; 1308 make_it_fail = task->make_it_fail; 1309 put_task_struct(task); 1310 1311 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1312 1313 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1314 } 1315 1316 static ssize_t proc_fault_inject_write(struct file * file, 1317 const char __user * buf, size_t count, loff_t *ppos) 1318 { 1319 struct task_struct *task; 1320 char buffer[PROC_NUMBUF]; 1321 int make_it_fail; 1322 int rv; 1323 1324 if (!capable(CAP_SYS_RESOURCE)) 1325 return -EPERM; 1326 memset(buffer, 0, sizeof(buffer)); 1327 if (count > sizeof(buffer) - 1) 1328 count = sizeof(buffer) - 1; 1329 if (copy_from_user(buffer, buf, count)) 1330 return -EFAULT; 1331 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail); 1332 if (rv < 0) 1333 return rv; 1334 if (make_it_fail < 0 || make_it_fail > 1) 1335 return -EINVAL; 1336 1337 task = get_proc_task(file_inode(file)); 1338 if (!task) 1339 return -ESRCH; 1340 task->make_it_fail = make_it_fail; 1341 put_task_struct(task); 1342 1343 return count; 1344 } 1345 1346 static const struct file_operations proc_fault_inject_operations = { 1347 .read = proc_fault_inject_read, 1348 .write = proc_fault_inject_write, 1349 .llseek = generic_file_llseek, 1350 }; 1351 1352 static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf, 1353 size_t count, loff_t *ppos) 1354 { 1355 struct task_struct *task; 1356 int err; 1357 unsigned int n; 1358 1359 err = kstrtouint_from_user(buf, count, 0, &n); 1360 if (err) 1361 return err; 1362 1363 task = get_proc_task(file_inode(file)); 1364 if (!task) 1365 return -ESRCH; 1366 task->fail_nth = n; 1367 put_task_struct(task); 1368 1369 return count; 1370 } 1371 1372 static ssize_t proc_fail_nth_read(struct file *file, char __user *buf, 1373 size_t count, loff_t *ppos) 1374 { 1375 struct task_struct *task; 1376 char numbuf[PROC_NUMBUF]; 1377 ssize_t len; 1378 1379 task = get_proc_task(file_inode(file)); 1380 if (!task) 1381 return -ESRCH; 1382 len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth); 1383 put_task_struct(task); 1384 return simple_read_from_buffer(buf, count, ppos, numbuf, len); 1385 } 1386 1387 static const struct file_operations proc_fail_nth_operations = { 1388 .read = proc_fail_nth_read, 1389 .write = proc_fail_nth_write, 1390 }; 1391 #endif 1392 1393 1394 #ifdef CONFIG_SCHED_DEBUG 1395 /* 1396 * Print out various scheduling related per-task fields: 1397 */ 1398 static int sched_show(struct seq_file *m, void *v) 1399 { 1400 struct inode *inode = m->private; 1401 struct pid_namespace *ns = proc_pid_ns(inode); 1402 struct task_struct *p; 1403 1404 p = get_proc_task(inode); 1405 if (!p) 1406 return -ESRCH; 1407 proc_sched_show_task(p, ns, m); 1408 1409 put_task_struct(p); 1410 1411 return 0; 1412 } 1413 1414 static ssize_t 1415 sched_write(struct file *file, const char __user *buf, 1416 size_t count, loff_t *offset) 1417 { 1418 struct inode *inode = file_inode(file); 1419 struct task_struct *p; 1420 1421 p = get_proc_task(inode); 1422 if (!p) 1423 return -ESRCH; 1424 proc_sched_set_task(p); 1425 1426 put_task_struct(p); 1427 1428 return count; 1429 } 1430 1431 static int sched_open(struct inode *inode, struct file *filp) 1432 { 1433 return single_open(filp, sched_show, inode); 1434 } 1435 1436 static const struct file_operations proc_pid_sched_operations = { 1437 .open = sched_open, 1438 .read = seq_read, 1439 .write = sched_write, 1440 .llseek = seq_lseek, 1441 .release = single_release, 1442 }; 1443 1444 #endif 1445 1446 #ifdef CONFIG_SCHED_AUTOGROUP 1447 /* 1448 * Print out autogroup related information: 1449 */ 1450 static int sched_autogroup_show(struct seq_file *m, void *v) 1451 { 1452 struct inode *inode = m->private; 1453 struct task_struct *p; 1454 1455 p = get_proc_task(inode); 1456 if (!p) 1457 return -ESRCH; 1458 proc_sched_autogroup_show_task(p, m); 1459 1460 put_task_struct(p); 1461 1462 return 0; 1463 } 1464 1465 static ssize_t 1466 sched_autogroup_write(struct file *file, const char __user *buf, 1467 size_t count, loff_t *offset) 1468 { 1469 struct inode *inode = file_inode(file); 1470 struct task_struct *p; 1471 char buffer[PROC_NUMBUF]; 1472 int nice; 1473 int err; 1474 1475 memset(buffer, 0, sizeof(buffer)); 1476 if (count > sizeof(buffer) - 1) 1477 count = sizeof(buffer) - 1; 1478 if (copy_from_user(buffer, buf, count)) 1479 return -EFAULT; 1480 1481 err = kstrtoint(strstrip(buffer), 0, &nice); 1482 if (err < 0) 1483 return err; 1484 1485 p = get_proc_task(inode); 1486 if (!p) 1487 return -ESRCH; 1488 1489 err = proc_sched_autogroup_set_nice(p, nice); 1490 if (err) 1491 count = err; 1492 1493 put_task_struct(p); 1494 1495 return count; 1496 } 1497 1498 static int sched_autogroup_open(struct inode *inode, struct file *filp) 1499 { 1500 int ret; 1501 1502 ret = single_open(filp, sched_autogroup_show, NULL); 1503 if (!ret) { 1504 struct seq_file *m = filp->private_data; 1505 1506 m->private = inode; 1507 } 1508 return ret; 1509 } 1510 1511 static const struct file_operations proc_pid_sched_autogroup_operations = { 1512 .open = sched_autogroup_open, 1513 .read = seq_read, 1514 .write = sched_autogroup_write, 1515 .llseek = seq_lseek, 1516 .release = single_release, 1517 }; 1518 1519 #endif /* CONFIG_SCHED_AUTOGROUP */ 1520 1521 static ssize_t comm_write(struct file *file, const char __user *buf, 1522 size_t count, loff_t *offset) 1523 { 1524 struct inode *inode = file_inode(file); 1525 struct task_struct *p; 1526 char buffer[TASK_COMM_LEN]; 1527 const size_t maxlen = sizeof(buffer) - 1; 1528 1529 memset(buffer, 0, sizeof(buffer)); 1530 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count)) 1531 return -EFAULT; 1532 1533 p = get_proc_task(inode); 1534 if (!p) 1535 return -ESRCH; 1536 1537 if (same_thread_group(current, p)) 1538 set_task_comm(p, buffer); 1539 else 1540 count = -EINVAL; 1541 1542 put_task_struct(p); 1543 1544 return count; 1545 } 1546 1547 static int comm_show(struct seq_file *m, void *v) 1548 { 1549 struct inode *inode = m->private; 1550 struct task_struct *p; 1551 1552 p = get_proc_task(inode); 1553 if (!p) 1554 return -ESRCH; 1555 1556 proc_task_name(m, p, false); 1557 seq_putc(m, '\n'); 1558 1559 put_task_struct(p); 1560 1561 return 0; 1562 } 1563 1564 static int comm_open(struct inode *inode, struct file *filp) 1565 { 1566 return single_open(filp, comm_show, inode); 1567 } 1568 1569 static const struct file_operations proc_pid_set_comm_operations = { 1570 .open = comm_open, 1571 .read = seq_read, 1572 .write = comm_write, 1573 .llseek = seq_lseek, 1574 .release = single_release, 1575 }; 1576 1577 static int proc_exe_link(struct dentry *dentry, struct path *exe_path) 1578 { 1579 struct task_struct *task; 1580 struct file *exe_file; 1581 1582 task = get_proc_task(d_inode(dentry)); 1583 if (!task) 1584 return -ENOENT; 1585 exe_file = get_task_exe_file(task); 1586 put_task_struct(task); 1587 if (exe_file) { 1588 *exe_path = exe_file->f_path; 1589 path_get(&exe_file->f_path); 1590 fput(exe_file); 1591 return 0; 1592 } else 1593 return -ENOENT; 1594 } 1595 1596 static const char *proc_pid_get_link(struct dentry *dentry, 1597 struct inode *inode, 1598 struct delayed_call *done) 1599 { 1600 struct path path; 1601 int error = -EACCES; 1602 1603 if (!dentry) 1604 return ERR_PTR(-ECHILD); 1605 1606 /* Are we allowed to snoop on the tasks file descriptors? */ 1607 if (!proc_fd_access_allowed(inode)) 1608 goto out; 1609 1610 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1611 if (error) 1612 goto out; 1613 1614 nd_jump_link(&path); 1615 return NULL; 1616 out: 1617 return ERR_PTR(error); 1618 } 1619 1620 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1621 { 1622 char *tmp = (char *)__get_free_page(GFP_KERNEL); 1623 char *pathname; 1624 int len; 1625 1626 if (!tmp) 1627 return -ENOMEM; 1628 1629 pathname = d_path(path, tmp, PAGE_SIZE); 1630 len = PTR_ERR(pathname); 1631 if (IS_ERR(pathname)) 1632 goto out; 1633 len = tmp + PAGE_SIZE - 1 - pathname; 1634 1635 if (len > buflen) 1636 len = buflen; 1637 if (copy_to_user(buffer, pathname, len)) 1638 len = -EFAULT; 1639 out: 1640 free_page((unsigned long)tmp); 1641 return len; 1642 } 1643 1644 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1645 { 1646 int error = -EACCES; 1647 struct inode *inode = d_inode(dentry); 1648 struct path path; 1649 1650 /* Are we allowed to snoop on the tasks file descriptors? */ 1651 if (!proc_fd_access_allowed(inode)) 1652 goto out; 1653 1654 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1655 if (error) 1656 goto out; 1657 1658 error = do_proc_readlink(&path, buffer, buflen); 1659 path_put(&path); 1660 out: 1661 return error; 1662 } 1663 1664 const struct inode_operations proc_pid_link_inode_operations = { 1665 .readlink = proc_pid_readlink, 1666 .get_link = proc_pid_get_link, 1667 .setattr = proc_setattr, 1668 }; 1669 1670 1671 /* building an inode */ 1672 1673 void task_dump_owner(struct task_struct *task, umode_t mode, 1674 kuid_t *ruid, kgid_t *rgid) 1675 { 1676 /* Depending on the state of dumpable compute who should own a 1677 * proc file for a task. 1678 */ 1679 const struct cred *cred; 1680 kuid_t uid; 1681 kgid_t gid; 1682 1683 if (unlikely(task->flags & PF_KTHREAD)) { 1684 *ruid = GLOBAL_ROOT_UID; 1685 *rgid = GLOBAL_ROOT_GID; 1686 return; 1687 } 1688 1689 /* Default to the tasks effective ownership */ 1690 rcu_read_lock(); 1691 cred = __task_cred(task); 1692 uid = cred->euid; 1693 gid = cred->egid; 1694 rcu_read_unlock(); 1695 1696 /* 1697 * Before the /proc/pid/status file was created the only way to read 1698 * the effective uid of a /process was to stat /proc/pid. Reading 1699 * /proc/pid/status is slow enough that procps and other packages 1700 * kept stating /proc/pid. To keep the rules in /proc simple I have 1701 * made this apply to all per process world readable and executable 1702 * directories. 1703 */ 1704 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) { 1705 struct mm_struct *mm; 1706 task_lock(task); 1707 mm = task->mm; 1708 /* Make non-dumpable tasks owned by some root */ 1709 if (mm) { 1710 if (get_dumpable(mm) != SUID_DUMP_USER) { 1711 struct user_namespace *user_ns = mm->user_ns; 1712 1713 uid = make_kuid(user_ns, 0); 1714 if (!uid_valid(uid)) 1715 uid = GLOBAL_ROOT_UID; 1716 1717 gid = make_kgid(user_ns, 0); 1718 if (!gid_valid(gid)) 1719 gid = GLOBAL_ROOT_GID; 1720 } 1721 } else { 1722 uid = GLOBAL_ROOT_UID; 1723 gid = GLOBAL_ROOT_GID; 1724 } 1725 task_unlock(task); 1726 } 1727 *ruid = uid; 1728 *rgid = gid; 1729 } 1730 1731 struct inode *proc_pid_make_inode(struct super_block * sb, 1732 struct task_struct *task, umode_t mode) 1733 { 1734 struct inode * inode; 1735 struct proc_inode *ei; 1736 1737 /* We need a new inode */ 1738 1739 inode = new_inode(sb); 1740 if (!inode) 1741 goto out; 1742 1743 /* Common stuff */ 1744 ei = PROC_I(inode); 1745 inode->i_mode = mode; 1746 inode->i_ino = get_next_ino(); 1747 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); 1748 inode->i_op = &proc_def_inode_operations; 1749 1750 /* 1751 * grab the reference to task. 1752 */ 1753 ei->pid = get_task_pid(task, PIDTYPE_PID); 1754 if (!ei->pid) 1755 goto out_unlock; 1756 1757 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1758 security_task_to_inode(task, inode); 1759 1760 out: 1761 return inode; 1762 1763 out_unlock: 1764 iput(inode); 1765 return NULL; 1766 } 1767 1768 int pid_getattr(const struct path *path, struct kstat *stat, 1769 u32 request_mask, unsigned int query_flags) 1770 { 1771 struct inode *inode = d_inode(path->dentry); 1772 struct pid_namespace *pid = proc_pid_ns(inode); 1773 struct task_struct *task; 1774 1775 generic_fillattr(inode, stat); 1776 1777 stat->uid = GLOBAL_ROOT_UID; 1778 stat->gid = GLOBAL_ROOT_GID; 1779 rcu_read_lock(); 1780 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1781 if (task) { 1782 if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) { 1783 rcu_read_unlock(); 1784 /* 1785 * This doesn't prevent learning whether PID exists, 1786 * it only makes getattr() consistent with readdir(). 1787 */ 1788 return -ENOENT; 1789 } 1790 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid); 1791 } 1792 rcu_read_unlock(); 1793 return 0; 1794 } 1795 1796 /* dentry stuff */ 1797 1798 /* 1799 * Set <pid>/... inode ownership (can change due to setuid(), etc.) 1800 */ 1801 void pid_update_inode(struct task_struct *task, struct inode *inode) 1802 { 1803 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid); 1804 1805 inode->i_mode &= ~(S_ISUID | S_ISGID); 1806 security_task_to_inode(task, inode); 1807 } 1808 1809 /* 1810 * Rewrite the inode's ownerships here because the owning task may have 1811 * performed a setuid(), etc. 1812 * 1813 */ 1814 static int pid_revalidate(struct dentry *dentry, unsigned int flags) 1815 { 1816 struct inode *inode; 1817 struct task_struct *task; 1818 1819 if (flags & LOOKUP_RCU) 1820 return -ECHILD; 1821 1822 inode = d_inode(dentry); 1823 task = get_proc_task(inode); 1824 1825 if (task) { 1826 pid_update_inode(task, inode); 1827 put_task_struct(task); 1828 return 1; 1829 } 1830 return 0; 1831 } 1832 1833 static inline bool proc_inode_is_dead(struct inode *inode) 1834 { 1835 return !proc_pid(inode)->tasks[PIDTYPE_PID].first; 1836 } 1837 1838 int pid_delete_dentry(const struct dentry *dentry) 1839 { 1840 /* Is the task we represent dead? 1841 * If so, then don't put the dentry on the lru list, 1842 * kill it immediately. 1843 */ 1844 return proc_inode_is_dead(d_inode(dentry)); 1845 } 1846 1847 const struct dentry_operations pid_dentry_operations = 1848 { 1849 .d_revalidate = pid_revalidate, 1850 .d_delete = pid_delete_dentry, 1851 }; 1852 1853 /* Lookups */ 1854 1855 /* 1856 * Fill a directory entry. 1857 * 1858 * If possible create the dcache entry and derive our inode number and 1859 * file type from dcache entry. 1860 * 1861 * Since all of the proc inode numbers are dynamically generated, the inode 1862 * numbers do not exist until the inode is cache. This means creating the 1863 * the dcache entry in readdir is necessary to keep the inode numbers 1864 * reported by readdir in sync with the inode numbers reported 1865 * by stat. 1866 */ 1867 bool proc_fill_cache(struct file *file, struct dir_context *ctx, 1868 const char *name, unsigned int len, 1869 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1870 { 1871 struct dentry *child, *dir = file->f_path.dentry; 1872 struct qstr qname = QSTR_INIT(name, len); 1873 struct inode *inode; 1874 unsigned type = DT_UNKNOWN; 1875 ino_t ino = 1; 1876 1877 child = d_hash_and_lookup(dir, &qname); 1878 if (!child) { 1879 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); 1880 child = d_alloc_parallel(dir, &qname, &wq); 1881 if (IS_ERR(child)) 1882 goto end_instantiate; 1883 if (d_in_lookup(child)) { 1884 struct dentry *res; 1885 res = instantiate(child, task, ptr); 1886 d_lookup_done(child); 1887 if (unlikely(res)) { 1888 dput(child); 1889 child = res; 1890 if (IS_ERR(child)) 1891 goto end_instantiate; 1892 } 1893 } 1894 } 1895 inode = d_inode(child); 1896 ino = inode->i_ino; 1897 type = inode->i_mode >> 12; 1898 dput(child); 1899 end_instantiate: 1900 return dir_emit(ctx, name, len, ino, type); 1901 } 1902 1903 /* 1904 * dname_to_vma_addr - maps a dentry name into two unsigned longs 1905 * which represent vma start and end addresses. 1906 */ 1907 static int dname_to_vma_addr(struct dentry *dentry, 1908 unsigned long *start, unsigned long *end) 1909 { 1910 const char *str = dentry->d_name.name; 1911 unsigned long long sval, eval; 1912 unsigned int len; 1913 1914 if (str[0] == '0' && str[1] != '-') 1915 return -EINVAL; 1916 len = _parse_integer(str, 16, &sval); 1917 if (len & KSTRTOX_OVERFLOW) 1918 return -EINVAL; 1919 if (sval != (unsigned long)sval) 1920 return -EINVAL; 1921 str += len; 1922 1923 if (*str != '-') 1924 return -EINVAL; 1925 str++; 1926 1927 if (str[0] == '0' && str[1]) 1928 return -EINVAL; 1929 len = _parse_integer(str, 16, &eval); 1930 if (len & KSTRTOX_OVERFLOW) 1931 return -EINVAL; 1932 if (eval != (unsigned long)eval) 1933 return -EINVAL; 1934 str += len; 1935 1936 if (*str != '\0') 1937 return -EINVAL; 1938 1939 *start = sval; 1940 *end = eval; 1941 1942 return 0; 1943 } 1944 1945 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) 1946 { 1947 unsigned long vm_start, vm_end; 1948 bool exact_vma_exists = false; 1949 struct mm_struct *mm = NULL; 1950 struct task_struct *task; 1951 struct inode *inode; 1952 int status = 0; 1953 1954 if (flags & LOOKUP_RCU) 1955 return -ECHILD; 1956 1957 inode = d_inode(dentry); 1958 task = get_proc_task(inode); 1959 if (!task) 1960 goto out_notask; 1961 1962 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); 1963 if (IS_ERR_OR_NULL(mm)) 1964 goto out; 1965 1966 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { 1967 down_read(&mm->mmap_sem); 1968 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); 1969 up_read(&mm->mmap_sem); 1970 } 1971 1972 mmput(mm); 1973 1974 if (exact_vma_exists) { 1975 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1976 1977 security_task_to_inode(task, inode); 1978 status = 1; 1979 } 1980 1981 out: 1982 put_task_struct(task); 1983 1984 out_notask: 1985 return status; 1986 } 1987 1988 static const struct dentry_operations tid_map_files_dentry_operations = { 1989 .d_revalidate = map_files_d_revalidate, 1990 .d_delete = pid_delete_dentry, 1991 }; 1992 1993 static int map_files_get_link(struct dentry *dentry, struct path *path) 1994 { 1995 unsigned long vm_start, vm_end; 1996 struct vm_area_struct *vma; 1997 struct task_struct *task; 1998 struct mm_struct *mm; 1999 int rc; 2000 2001 rc = -ENOENT; 2002 task = get_proc_task(d_inode(dentry)); 2003 if (!task) 2004 goto out; 2005 2006 mm = get_task_mm(task); 2007 put_task_struct(task); 2008 if (!mm) 2009 goto out; 2010 2011 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); 2012 if (rc) 2013 goto out_mmput; 2014 2015 rc = -ENOENT; 2016 down_read(&mm->mmap_sem); 2017 vma = find_exact_vma(mm, vm_start, vm_end); 2018 if (vma && vma->vm_file) { 2019 *path = vma->vm_file->f_path; 2020 path_get(path); 2021 rc = 0; 2022 } 2023 up_read(&mm->mmap_sem); 2024 2025 out_mmput: 2026 mmput(mm); 2027 out: 2028 return rc; 2029 } 2030 2031 struct map_files_info { 2032 unsigned long start; 2033 unsigned long end; 2034 fmode_t mode; 2035 }; 2036 2037 /* 2038 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the 2039 * symlinks may be used to bypass permissions on ancestor directories in the 2040 * path to the file in question. 2041 */ 2042 static const char * 2043 proc_map_files_get_link(struct dentry *dentry, 2044 struct inode *inode, 2045 struct delayed_call *done) 2046 { 2047 if (!capable(CAP_SYS_ADMIN)) 2048 return ERR_PTR(-EPERM); 2049 2050 return proc_pid_get_link(dentry, inode, done); 2051 } 2052 2053 /* 2054 * Identical to proc_pid_link_inode_operations except for get_link() 2055 */ 2056 static const struct inode_operations proc_map_files_link_inode_operations = { 2057 .readlink = proc_pid_readlink, 2058 .get_link = proc_map_files_get_link, 2059 .setattr = proc_setattr, 2060 }; 2061 2062 static struct dentry * 2063 proc_map_files_instantiate(struct dentry *dentry, 2064 struct task_struct *task, const void *ptr) 2065 { 2066 fmode_t mode = (fmode_t)(unsigned long)ptr; 2067 struct proc_inode *ei; 2068 struct inode *inode; 2069 2070 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK | 2071 ((mode & FMODE_READ ) ? S_IRUSR : 0) | 2072 ((mode & FMODE_WRITE) ? S_IWUSR : 0)); 2073 if (!inode) 2074 return ERR_PTR(-ENOENT); 2075 2076 ei = PROC_I(inode); 2077 ei->op.proc_get_link = map_files_get_link; 2078 2079 inode->i_op = &proc_map_files_link_inode_operations; 2080 inode->i_size = 64; 2081 2082 d_set_d_op(dentry, &tid_map_files_dentry_operations); 2083 return d_splice_alias(inode, dentry); 2084 } 2085 2086 static struct dentry *proc_map_files_lookup(struct inode *dir, 2087 struct dentry *dentry, unsigned int flags) 2088 { 2089 unsigned long vm_start, vm_end; 2090 struct vm_area_struct *vma; 2091 struct task_struct *task; 2092 struct dentry *result; 2093 struct mm_struct *mm; 2094 2095 result = ERR_PTR(-ENOENT); 2096 task = get_proc_task(dir); 2097 if (!task) 2098 goto out; 2099 2100 result = ERR_PTR(-EACCES); 2101 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2102 goto out_put_task; 2103 2104 result = ERR_PTR(-ENOENT); 2105 if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) 2106 goto out_put_task; 2107 2108 mm = get_task_mm(task); 2109 if (!mm) 2110 goto out_put_task; 2111 2112 down_read(&mm->mmap_sem); 2113 vma = find_exact_vma(mm, vm_start, vm_end); 2114 if (!vma) 2115 goto out_no_vma; 2116 2117 if (vma->vm_file) 2118 result = proc_map_files_instantiate(dentry, task, 2119 (void *)(unsigned long)vma->vm_file->f_mode); 2120 2121 out_no_vma: 2122 up_read(&mm->mmap_sem); 2123 mmput(mm); 2124 out_put_task: 2125 put_task_struct(task); 2126 out: 2127 return result; 2128 } 2129 2130 static const struct inode_operations proc_map_files_inode_operations = { 2131 .lookup = proc_map_files_lookup, 2132 .permission = proc_fd_permission, 2133 .setattr = proc_setattr, 2134 }; 2135 2136 static int 2137 proc_map_files_readdir(struct file *file, struct dir_context *ctx) 2138 { 2139 struct vm_area_struct *vma; 2140 struct task_struct *task; 2141 struct mm_struct *mm; 2142 unsigned long nr_files, pos, i; 2143 struct flex_array *fa = NULL; 2144 struct map_files_info info; 2145 struct map_files_info *p; 2146 int ret; 2147 2148 ret = -ENOENT; 2149 task = get_proc_task(file_inode(file)); 2150 if (!task) 2151 goto out; 2152 2153 ret = -EACCES; 2154 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2155 goto out_put_task; 2156 2157 ret = 0; 2158 if (!dir_emit_dots(file, ctx)) 2159 goto out_put_task; 2160 2161 mm = get_task_mm(task); 2162 if (!mm) 2163 goto out_put_task; 2164 down_read(&mm->mmap_sem); 2165 2166 nr_files = 0; 2167 2168 /* 2169 * We need two passes here: 2170 * 2171 * 1) Collect vmas of mapped files with mmap_sem taken 2172 * 2) Release mmap_sem and instantiate entries 2173 * 2174 * otherwise we get lockdep complained, since filldir() 2175 * routine might require mmap_sem taken in might_fault(). 2176 */ 2177 2178 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { 2179 if (vma->vm_file && ++pos > ctx->pos) 2180 nr_files++; 2181 } 2182 2183 if (nr_files) { 2184 fa = flex_array_alloc(sizeof(info), nr_files, 2185 GFP_KERNEL); 2186 if (!fa || flex_array_prealloc(fa, 0, nr_files, 2187 GFP_KERNEL)) { 2188 ret = -ENOMEM; 2189 if (fa) 2190 flex_array_free(fa); 2191 up_read(&mm->mmap_sem); 2192 mmput(mm); 2193 goto out_put_task; 2194 } 2195 for (i = 0, vma = mm->mmap, pos = 2; vma; 2196 vma = vma->vm_next) { 2197 if (!vma->vm_file) 2198 continue; 2199 if (++pos <= ctx->pos) 2200 continue; 2201 2202 info.start = vma->vm_start; 2203 info.end = vma->vm_end; 2204 info.mode = vma->vm_file->f_mode; 2205 if (flex_array_put(fa, i++, &info, GFP_KERNEL)) 2206 BUG(); 2207 } 2208 } 2209 up_read(&mm->mmap_sem); 2210 mmput(mm); 2211 2212 for (i = 0; i < nr_files; i++) { 2213 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */ 2214 unsigned int len; 2215 2216 p = flex_array_get(fa, i); 2217 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end); 2218 if (!proc_fill_cache(file, ctx, 2219 buf, len, 2220 proc_map_files_instantiate, 2221 task, 2222 (void *)(unsigned long)p->mode)) 2223 break; 2224 ctx->pos++; 2225 } 2226 if (fa) 2227 flex_array_free(fa); 2228 2229 out_put_task: 2230 put_task_struct(task); 2231 out: 2232 return ret; 2233 } 2234 2235 static const struct file_operations proc_map_files_operations = { 2236 .read = generic_read_dir, 2237 .iterate_shared = proc_map_files_readdir, 2238 .llseek = generic_file_llseek, 2239 }; 2240 2241 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 2242 struct timers_private { 2243 struct pid *pid; 2244 struct task_struct *task; 2245 struct sighand_struct *sighand; 2246 struct pid_namespace *ns; 2247 unsigned long flags; 2248 }; 2249 2250 static void *timers_start(struct seq_file *m, loff_t *pos) 2251 { 2252 struct timers_private *tp = m->private; 2253 2254 tp->task = get_pid_task(tp->pid, PIDTYPE_PID); 2255 if (!tp->task) 2256 return ERR_PTR(-ESRCH); 2257 2258 tp->sighand = lock_task_sighand(tp->task, &tp->flags); 2259 if (!tp->sighand) 2260 return ERR_PTR(-ESRCH); 2261 2262 return seq_list_start(&tp->task->signal->posix_timers, *pos); 2263 } 2264 2265 static void *timers_next(struct seq_file *m, void *v, loff_t *pos) 2266 { 2267 struct timers_private *tp = m->private; 2268 return seq_list_next(v, &tp->task->signal->posix_timers, pos); 2269 } 2270 2271 static void timers_stop(struct seq_file *m, void *v) 2272 { 2273 struct timers_private *tp = m->private; 2274 2275 if (tp->sighand) { 2276 unlock_task_sighand(tp->task, &tp->flags); 2277 tp->sighand = NULL; 2278 } 2279 2280 if (tp->task) { 2281 put_task_struct(tp->task); 2282 tp->task = NULL; 2283 } 2284 } 2285 2286 static int show_timer(struct seq_file *m, void *v) 2287 { 2288 struct k_itimer *timer; 2289 struct timers_private *tp = m->private; 2290 int notify; 2291 static const char * const nstr[] = { 2292 [SIGEV_SIGNAL] = "signal", 2293 [SIGEV_NONE] = "none", 2294 [SIGEV_THREAD] = "thread", 2295 }; 2296 2297 timer = list_entry((struct list_head *)v, struct k_itimer, list); 2298 notify = timer->it_sigev_notify; 2299 2300 seq_printf(m, "ID: %d\n", timer->it_id); 2301 seq_printf(m, "signal: %d/%px\n", 2302 timer->sigq->info.si_signo, 2303 timer->sigq->info.si_value.sival_ptr); 2304 seq_printf(m, "notify: %s/%s.%d\n", 2305 nstr[notify & ~SIGEV_THREAD_ID], 2306 (notify & SIGEV_THREAD_ID) ? "tid" : "pid", 2307 pid_nr_ns(timer->it_pid, tp->ns)); 2308 seq_printf(m, "ClockID: %d\n", timer->it_clock); 2309 2310 return 0; 2311 } 2312 2313 static const struct seq_operations proc_timers_seq_ops = { 2314 .start = timers_start, 2315 .next = timers_next, 2316 .stop = timers_stop, 2317 .show = show_timer, 2318 }; 2319 2320 static int proc_timers_open(struct inode *inode, struct file *file) 2321 { 2322 struct timers_private *tp; 2323 2324 tp = __seq_open_private(file, &proc_timers_seq_ops, 2325 sizeof(struct timers_private)); 2326 if (!tp) 2327 return -ENOMEM; 2328 2329 tp->pid = proc_pid(inode); 2330 tp->ns = proc_pid_ns(inode); 2331 return 0; 2332 } 2333 2334 static const struct file_operations proc_timers_operations = { 2335 .open = proc_timers_open, 2336 .read = seq_read, 2337 .llseek = seq_lseek, 2338 .release = seq_release_private, 2339 }; 2340 #endif 2341 2342 static ssize_t timerslack_ns_write(struct file *file, const char __user *buf, 2343 size_t count, loff_t *offset) 2344 { 2345 struct inode *inode = file_inode(file); 2346 struct task_struct *p; 2347 u64 slack_ns; 2348 int err; 2349 2350 err = kstrtoull_from_user(buf, count, 10, &slack_ns); 2351 if (err < 0) 2352 return err; 2353 2354 p = get_proc_task(inode); 2355 if (!p) 2356 return -ESRCH; 2357 2358 if (p != current) { 2359 if (!capable(CAP_SYS_NICE)) { 2360 count = -EPERM; 2361 goto out; 2362 } 2363 2364 err = security_task_setscheduler(p); 2365 if (err) { 2366 count = err; 2367 goto out; 2368 } 2369 } 2370 2371 task_lock(p); 2372 if (slack_ns == 0) 2373 p->timer_slack_ns = p->default_timer_slack_ns; 2374 else 2375 p->timer_slack_ns = slack_ns; 2376 task_unlock(p); 2377 2378 out: 2379 put_task_struct(p); 2380 2381 return count; 2382 } 2383 2384 static int timerslack_ns_show(struct seq_file *m, void *v) 2385 { 2386 struct inode *inode = m->private; 2387 struct task_struct *p; 2388 int err = 0; 2389 2390 p = get_proc_task(inode); 2391 if (!p) 2392 return -ESRCH; 2393 2394 if (p != current) { 2395 2396 if (!capable(CAP_SYS_NICE)) { 2397 err = -EPERM; 2398 goto out; 2399 } 2400 err = security_task_getscheduler(p); 2401 if (err) 2402 goto out; 2403 } 2404 2405 task_lock(p); 2406 seq_printf(m, "%llu\n", p->timer_slack_ns); 2407 task_unlock(p); 2408 2409 out: 2410 put_task_struct(p); 2411 2412 return err; 2413 } 2414 2415 static int timerslack_ns_open(struct inode *inode, struct file *filp) 2416 { 2417 return single_open(filp, timerslack_ns_show, inode); 2418 } 2419 2420 static const struct file_operations proc_pid_set_timerslack_ns_operations = { 2421 .open = timerslack_ns_open, 2422 .read = seq_read, 2423 .write = timerslack_ns_write, 2424 .llseek = seq_lseek, 2425 .release = single_release, 2426 }; 2427 2428 static struct dentry *proc_pident_instantiate(struct dentry *dentry, 2429 struct task_struct *task, const void *ptr) 2430 { 2431 const struct pid_entry *p = ptr; 2432 struct inode *inode; 2433 struct proc_inode *ei; 2434 2435 inode = proc_pid_make_inode(dentry->d_sb, task, p->mode); 2436 if (!inode) 2437 return ERR_PTR(-ENOENT); 2438 2439 ei = PROC_I(inode); 2440 if (S_ISDIR(inode->i_mode)) 2441 set_nlink(inode, 2); /* Use getattr to fix if necessary */ 2442 if (p->iop) 2443 inode->i_op = p->iop; 2444 if (p->fop) 2445 inode->i_fop = p->fop; 2446 ei->op = p->op; 2447 pid_update_inode(task, inode); 2448 d_set_d_op(dentry, &pid_dentry_operations); 2449 return d_splice_alias(inode, dentry); 2450 } 2451 2452 static struct dentry *proc_pident_lookup(struct inode *dir, 2453 struct dentry *dentry, 2454 const struct pid_entry *ents, 2455 unsigned int nents) 2456 { 2457 struct task_struct *task = get_proc_task(dir); 2458 const struct pid_entry *p, *last; 2459 struct dentry *res = ERR_PTR(-ENOENT); 2460 2461 if (!task) 2462 goto out_no_task; 2463 2464 /* 2465 * Yes, it does not scale. And it should not. Don't add 2466 * new entries into /proc/<tgid>/ without very good reasons. 2467 */ 2468 last = &ents[nents]; 2469 for (p = ents; p < last; p++) { 2470 if (p->len != dentry->d_name.len) 2471 continue; 2472 if (!memcmp(dentry->d_name.name, p->name, p->len)) { 2473 res = proc_pident_instantiate(dentry, task, p); 2474 break; 2475 } 2476 } 2477 put_task_struct(task); 2478 out_no_task: 2479 return res; 2480 } 2481 2482 static int proc_pident_readdir(struct file *file, struct dir_context *ctx, 2483 const struct pid_entry *ents, unsigned int nents) 2484 { 2485 struct task_struct *task = get_proc_task(file_inode(file)); 2486 const struct pid_entry *p; 2487 2488 if (!task) 2489 return -ENOENT; 2490 2491 if (!dir_emit_dots(file, ctx)) 2492 goto out; 2493 2494 if (ctx->pos >= nents + 2) 2495 goto out; 2496 2497 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) { 2498 if (!proc_fill_cache(file, ctx, p->name, p->len, 2499 proc_pident_instantiate, task, p)) 2500 break; 2501 ctx->pos++; 2502 } 2503 out: 2504 put_task_struct(task); 2505 return 0; 2506 } 2507 2508 #ifdef CONFIG_SECURITY 2509 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2510 size_t count, loff_t *ppos) 2511 { 2512 struct inode * inode = file_inode(file); 2513 char *p = NULL; 2514 ssize_t length; 2515 struct task_struct *task = get_proc_task(inode); 2516 2517 if (!task) 2518 return -ESRCH; 2519 2520 length = security_getprocattr(task, 2521 (char*)file->f_path.dentry->d_name.name, 2522 &p); 2523 put_task_struct(task); 2524 if (length > 0) 2525 length = simple_read_from_buffer(buf, count, ppos, p, length); 2526 kfree(p); 2527 return length; 2528 } 2529 2530 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2531 size_t count, loff_t *ppos) 2532 { 2533 struct inode * inode = file_inode(file); 2534 struct task_struct *task; 2535 void *page; 2536 int rv; 2537 2538 rcu_read_lock(); 2539 task = pid_task(proc_pid(inode), PIDTYPE_PID); 2540 if (!task) { 2541 rcu_read_unlock(); 2542 return -ESRCH; 2543 } 2544 /* A task may only write its own attributes. */ 2545 if (current != task) { 2546 rcu_read_unlock(); 2547 return -EACCES; 2548 } 2549 rcu_read_unlock(); 2550 2551 if (count > PAGE_SIZE) 2552 count = PAGE_SIZE; 2553 2554 /* No partial writes. */ 2555 if (*ppos != 0) 2556 return -EINVAL; 2557 2558 page = memdup_user(buf, count); 2559 if (IS_ERR(page)) { 2560 rv = PTR_ERR(page); 2561 goto out; 2562 } 2563 2564 /* Guard against adverse ptrace interaction */ 2565 rv = mutex_lock_interruptible(¤t->signal->cred_guard_mutex); 2566 if (rv < 0) 2567 goto out_free; 2568 2569 rv = security_setprocattr(file->f_path.dentry->d_name.name, page, count); 2570 mutex_unlock(¤t->signal->cred_guard_mutex); 2571 out_free: 2572 kfree(page); 2573 out: 2574 return rv; 2575 } 2576 2577 static const struct file_operations proc_pid_attr_operations = { 2578 .read = proc_pid_attr_read, 2579 .write = proc_pid_attr_write, 2580 .llseek = generic_file_llseek, 2581 }; 2582 2583 static const struct pid_entry attr_dir_stuff[] = { 2584 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2585 REG("prev", S_IRUGO, proc_pid_attr_operations), 2586 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2587 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2588 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2589 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2590 }; 2591 2592 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) 2593 { 2594 return proc_pident_readdir(file, ctx, 2595 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2596 } 2597 2598 static const struct file_operations proc_attr_dir_operations = { 2599 .read = generic_read_dir, 2600 .iterate_shared = proc_attr_dir_readdir, 2601 .llseek = generic_file_llseek, 2602 }; 2603 2604 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2605 struct dentry *dentry, unsigned int flags) 2606 { 2607 return proc_pident_lookup(dir, dentry, 2608 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2609 } 2610 2611 static const struct inode_operations proc_attr_dir_inode_operations = { 2612 .lookup = proc_attr_dir_lookup, 2613 .getattr = pid_getattr, 2614 .setattr = proc_setattr, 2615 }; 2616 2617 #endif 2618 2619 #ifdef CONFIG_ELF_CORE 2620 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2621 size_t count, loff_t *ppos) 2622 { 2623 struct task_struct *task = get_proc_task(file_inode(file)); 2624 struct mm_struct *mm; 2625 char buffer[PROC_NUMBUF]; 2626 size_t len; 2627 int ret; 2628 2629 if (!task) 2630 return -ESRCH; 2631 2632 ret = 0; 2633 mm = get_task_mm(task); 2634 if (mm) { 2635 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2636 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2637 MMF_DUMP_FILTER_SHIFT)); 2638 mmput(mm); 2639 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2640 } 2641 2642 put_task_struct(task); 2643 2644 return ret; 2645 } 2646 2647 static ssize_t proc_coredump_filter_write(struct file *file, 2648 const char __user *buf, 2649 size_t count, 2650 loff_t *ppos) 2651 { 2652 struct task_struct *task; 2653 struct mm_struct *mm; 2654 unsigned int val; 2655 int ret; 2656 int i; 2657 unsigned long mask; 2658 2659 ret = kstrtouint_from_user(buf, count, 0, &val); 2660 if (ret < 0) 2661 return ret; 2662 2663 ret = -ESRCH; 2664 task = get_proc_task(file_inode(file)); 2665 if (!task) 2666 goto out_no_task; 2667 2668 mm = get_task_mm(task); 2669 if (!mm) 2670 goto out_no_mm; 2671 ret = 0; 2672 2673 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2674 if (val & mask) 2675 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2676 else 2677 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2678 } 2679 2680 mmput(mm); 2681 out_no_mm: 2682 put_task_struct(task); 2683 out_no_task: 2684 if (ret < 0) 2685 return ret; 2686 return count; 2687 } 2688 2689 static const struct file_operations proc_coredump_filter_operations = { 2690 .read = proc_coredump_filter_read, 2691 .write = proc_coredump_filter_write, 2692 .llseek = generic_file_llseek, 2693 }; 2694 #endif 2695 2696 #ifdef CONFIG_TASK_IO_ACCOUNTING 2697 static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) 2698 { 2699 struct task_io_accounting acct = task->ioac; 2700 unsigned long flags; 2701 int result; 2702 2703 result = mutex_lock_killable(&task->signal->cred_guard_mutex); 2704 if (result) 2705 return result; 2706 2707 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { 2708 result = -EACCES; 2709 goto out_unlock; 2710 } 2711 2712 if (whole && lock_task_sighand(task, &flags)) { 2713 struct task_struct *t = task; 2714 2715 task_io_accounting_add(&acct, &task->signal->ioac); 2716 while_each_thread(task, t) 2717 task_io_accounting_add(&acct, &t->ioac); 2718 2719 unlock_task_sighand(task, &flags); 2720 } 2721 seq_printf(m, 2722 "rchar: %llu\n" 2723 "wchar: %llu\n" 2724 "syscr: %llu\n" 2725 "syscw: %llu\n" 2726 "read_bytes: %llu\n" 2727 "write_bytes: %llu\n" 2728 "cancelled_write_bytes: %llu\n", 2729 (unsigned long long)acct.rchar, 2730 (unsigned long long)acct.wchar, 2731 (unsigned long long)acct.syscr, 2732 (unsigned long long)acct.syscw, 2733 (unsigned long long)acct.read_bytes, 2734 (unsigned long long)acct.write_bytes, 2735 (unsigned long long)acct.cancelled_write_bytes); 2736 result = 0; 2737 2738 out_unlock: 2739 mutex_unlock(&task->signal->cred_guard_mutex); 2740 return result; 2741 } 2742 2743 static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2744 struct pid *pid, struct task_struct *task) 2745 { 2746 return do_io_accounting(task, m, 0); 2747 } 2748 2749 static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2750 struct pid *pid, struct task_struct *task) 2751 { 2752 return do_io_accounting(task, m, 1); 2753 } 2754 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2755 2756 #ifdef CONFIG_USER_NS 2757 static int proc_id_map_open(struct inode *inode, struct file *file, 2758 const struct seq_operations *seq_ops) 2759 { 2760 struct user_namespace *ns = NULL; 2761 struct task_struct *task; 2762 struct seq_file *seq; 2763 int ret = -EINVAL; 2764 2765 task = get_proc_task(inode); 2766 if (task) { 2767 rcu_read_lock(); 2768 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2769 rcu_read_unlock(); 2770 put_task_struct(task); 2771 } 2772 if (!ns) 2773 goto err; 2774 2775 ret = seq_open(file, seq_ops); 2776 if (ret) 2777 goto err_put_ns; 2778 2779 seq = file->private_data; 2780 seq->private = ns; 2781 2782 return 0; 2783 err_put_ns: 2784 put_user_ns(ns); 2785 err: 2786 return ret; 2787 } 2788 2789 static int proc_id_map_release(struct inode *inode, struct file *file) 2790 { 2791 struct seq_file *seq = file->private_data; 2792 struct user_namespace *ns = seq->private; 2793 put_user_ns(ns); 2794 return seq_release(inode, file); 2795 } 2796 2797 static int proc_uid_map_open(struct inode *inode, struct file *file) 2798 { 2799 return proc_id_map_open(inode, file, &proc_uid_seq_operations); 2800 } 2801 2802 static int proc_gid_map_open(struct inode *inode, struct file *file) 2803 { 2804 return proc_id_map_open(inode, file, &proc_gid_seq_operations); 2805 } 2806 2807 static int proc_projid_map_open(struct inode *inode, struct file *file) 2808 { 2809 return proc_id_map_open(inode, file, &proc_projid_seq_operations); 2810 } 2811 2812 static const struct file_operations proc_uid_map_operations = { 2813 .open = proc_uid_map_open, 2814 .write = proc_uid_map_write, 2815 .read = seq_read, 2816 .llseek = seq_lseek, 2817 .release = proc_id_map_release, 2818 }; 2819 2820 static const struct file_operations proc_gid_map_operations = { 2821 .open = proc_gid_map_open, 2822 .write = proc_gid_map_write, 2823 .read = seq_read, 2824 .llseek = seq_lseek, 2825 .release = proc_id_map_release, 2826 }; 2827 2828 static const struct file_operations proc_projid_map_operations = { 2829 .open = proc_projid_map_open, 2830 .write = proc_projid_map_write, 2831 .read = seq_read, 2832 .llseek = seq_lseek, 2833 .release = proc_id_map_release, 2834 }; 2835 2836 static int proc_setgroups_open(struct inode *inode, struct file *file) 2837 { 2838 struct user_namespace *ns = NULL; 2839 struct task_struct *task; 2840 int ret; 2841 2842 ret = -ESRCH; 2843 task = get_proc_task(inode); 2844 if (task) { 2845 rcu_read_lock(); 2846 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2847 rcu_read_unlock(); 2848 put_task_struct(task); 2849 } 2850 if (!ns) 2851 goto err; 2852 2853 if (file->f_mode & FMODE_WRITE) { 2854 ret = -EACCES; 2855 if (!ns_capable(ns, CAP_SYS_ADMIN)) 2856 goto err_put_ns; 2857 } 2858 2859 ret = single_open(file, &proc_setgroups_show, ns); 2860 if (ret) 2861 goto err_put_ns; 2862 2863 return 0; 2864 err_put_ns: 2865 put_user_ns(ns); 2866 err: 2867 return ret; 2868 } 2869 2870 static int proc_setgroups_release(struct inode *inode, struct file *file) 2871 { 2872 struct seq_file *seq = file->private_data; 2873 struct user_namespace *ns = seq->private; 2874 int ret = single_release(inode, file); 2875 put_user_ns(ns); 2876 return ret; 2877 } 2878 2879 static const struct file_operations proc_setgroups_operations = { 2880 .open = proc_setgroups_open, 2881 .write = proc_setgroups_write, 2882 .read = seq_read, 2883 .llseek = seq_lseek, 2884 .release = proc_setgroups_release, 2885 }; 2886 #endif /* CONFIG_USER_NS */ 2887 2888 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2889 struct pid *pid, struct task_struct *task) 2890 { 2891 int err = lock_trace(task); 2892 if (!err) { 2893 seq_printf(m, "%08x\n", task->personality); 2894 unlock_trace(task); 2895 } 2896 return err; 2897 } 2898 2899 #ifdef CONFIG_LIVEPATCH 2900 static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns, 2901 struct pid *pid, struct task_struct *task) 2902 { 2903 seq_printf(m, "%d\n", task->patch_state); 2904 return 0; 2905 } 2906 #endif /* CONFIG_LIVEPATCH */ 2907 2908 /* 2909 * Thread groups 2910 */ 2911 static const struct file_operations proc_task_operations; 2912 static const struct inode_operations proc_task_inode_operations; 2913 2914 static const struct pid_entry tgid_base_stuff[] = { 2915 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2916 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2917 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), 2918 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2919 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2920 #ifdef CONFIG_NET 2921 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2922 #endif 2923 REG("environ", S_IRUSR, proc_environ_operations), 2924 REG("auxv", S_IRUSR, proc_auxv_operations), 2925 ONE("status", S_IRUGO, proc_pid_status), 2926 ONE("personality", S_IRUSR, proc_pid_personality), 2927 ONE("limits", S_IRUGO, proc_pid_limits), 2928 #ifdef CONFIG_SCHED_DEBUG 2929 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2930 #endif 2931 #ifdef CONFIG_SCHED_AUTOGROUP 2932 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), 2933 #endif 2934 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2935 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2936 ONE("syscall", S_IRUSR, proc_pid_syscall), 2937 #endif 2938 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 2939 ONE("stat", S_IRUGO, proc_tgid_stat), 2940 ONE("statm", S_IRUGO, proc_pid_statm), 2941 REG("maps", S_IRUGO, proc_pid_maps_operations), 2942 #ifdef CONFIG_NUMA 2943 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 2944 #endif 2945 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2946 LNK("cwd", proc_cwd_link), 2947 LNK("root", proc_root_link), 2948 LNK("exe", proc_exe_link), 2949 REG("mounts", S_IRUGO, proc_mounts_operations), 2950 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2951 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2952 #ifdef CONFIG_PROC_PAGE_MONITOR 2953 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2954 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 2955 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), 2956 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2957 #endif 2958 #ifdef CONFIG_SECURITY 2959 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2960 #endif 2961 #ifdef CONFIG_KALLSYMS 2962 ONE("wchan", S_IRUGO, proc_pid_wchan), 2963 #endif 2964 #ifdef CONFIG_STACKTRACE 2965 ONE("stack", S_IRUSR, proc_pid_stack), 2966 #endif 2967 #ifdef CONFIG_SCHED_INFO 2968 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 2969 #endif 2970 #ifdef CONFIG_LATENCYTOP 2971 REG("latency", S_IRUGO, proc_lstats_operations), 2972 #endif 2973 #ifdef CONFIG_PROC_PID_CPUSET 2974 ONE("cpuset", S_IRUGO, proc_cpuset_show), 2975 #endif 2976 #ifdef CONFIG_CGROUPS 2977 ONE("cgroup", S_IRUGO, proc_cgroup_show), 2978 #endif 2979 ONE("oom_score", S_IRUGO, proc_oom_score), 2980 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 2981 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2982 #ifdef CONFIG_AUDITSYSCALL 2983 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2984 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2985 #endif 2986 #ifdef CONFIG_FAULT_INJECTION 2987 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2988 REG("fail-nth", 0644, proc_fail_nth_operations), 2989 #endif 2990 #ifdef CONFIG_ELF_CORE 2991 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2992 #endif 2993 #ifdef CONFIG_TASK_IO_ACCOUNTING 2994 ONE("io", S_IRUSR, proc_tgid_io_accounting), 2995 #endif 2996 #ifdef CONFIG_USER_NS 2997 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2998 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2999 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 3000 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 3001 #endif 3002 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 3003 REG("timers", S_IRUGO, proc_timers_operations), 3004 #endif 3005 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations), 3006 #ifdef CONFIG_LIVEPATCH 3007 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 3008 #endif 3009 }; 3010 3011 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) 3012 { 3013 return proc_pident_readdir(file, ctx, 3014 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3015 } 3016 3017 static const struct file_operations proc_tgid_base_operations = { 3018 .read = generic_read_dir, 3019 .iterate_shared = proc_tgid_base_readdir, 3020 .llseek = generic_file_llseek, 3021 }; 3022 3023 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3024 { 3025 return proc_pident_lookup(dir, dentry, 3026 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3027 } 3028 3029 static const struct inode_operations proc_tgid_base_inode_operations = { 3030 .lookup = proc_tgid_base_lookup, 3031 .getattr = pid_getattr, 3032 .setattr = proc_setattr, 3033 .permission = proc_pid_permission, 3034 }; 3035 3036 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 3037 { 3038 struct dentry *dentry, *leader, *dir; 3039 char buf[10 + 1]; 3040 struct qstr name; 3041 3042 name.name = buf; 3043 name.len = snprintf(buf, sizeof(buf), "%u", pid); 3044 /* no ->d_hash() rejects on procfs */ 3045 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 3046 if (dentry) { 3047 d_invalidate(dentry); 3048 dput(dentry); 3049 } 3050 3051 if (pid == tgid) 3052 return; 3053 3054 name.name = buf; 3055 name.len = snprintf(buf, sizeof(buf), "%u", tgid); 3056 leader = d_hash_and_lookup(mnt->mnt_root, &name); 3057 if (!leader) 3058 goto out; 3059 3060 name.name = "task"; 3061 name.len = strlen(name.name); 3062 dir = d_hash_and_lookup(leader, &name); 3063 if (!dir) 3064 goto out_put_leader; 3065 3066 name.name = buf; 3067 name.len = snprintf(buf, sizeof(buf), "%u", pid); 3068 dentry = d_hash_and_lookup(dir, &name); 3069 if (dentry) { 3070 d_invalidate(dentry); 3071 dput(dentry); 3072 } 3073 3074 dput(dir); 3075 out_put_leader: 3076 dput(leader); 3077 out: 3078 return; 3079 } 3080 3081 /** 3082 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 3083 * @task: task that should be flushed. 3084 * 3085 * When flushing dentries from proc, one needs to flush them from global 3086 * proc (proc_mnt) and from all the namespaces' procs this task was seen 3087 * in. This call is supposed to do all of this job. 3088 * 3089 * Looks in the dcache for 3090 * /proc/@pid 3091 * /proc/@tgid/task/@pid 3092 * if either directory is present flushes it and all of it'ts children 3093 * from the dcache. 3094 * 3095 * It is safe and reasonable to cache /proc entries for a task until 3096 * that task exits. After that they just clog up the dcache with 3097 * useless entries, possibly causing useful dcache entries to be 3098 * flushed instead. This routine is proved to flush those useless 3099 * dcache entries at process exit time. 3100 * 3101 * NOTE: This routine is just an optimization so it does not guarantee 3102 * that no dcache entries will exist at process exit time it 3103 * just makes it very unlikely that any will persist. 3104 */ 3105 3106 void proc_flush_task(struct task_struct *task) 3107 { 3108 int i; 3109 struct pid *pid, *tgid; 3110 struct upid *upid; 3111 3112 pid = task_pid(task); 3113 tgid = task_tgid(task); 3114 3115 for (i = 0; i <= pid->level; i++) { 3116 upid = &pid->numbers[i]; 3117 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 3118 tgid->numbers[i].nr); 3119 } 3120 } 3121 3122 static struct dentry *proc_pid_instantiate(struct dentry * dentry, 3123 struct task_struct *task, const void *ptr) 3124 { 3125 struct inode *inode; 3126 3127 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); 3128 if (!inode) 3129 return ERR_PTR(-ENOENT); 3130 3131 inode->i_op = &proc_tgid_base_inode_operations; 3132 inode->i_fop = &proc_tgid_base_operations; 3133 inode->i_flags|=S_IMMUTABLE; 3134 3135 set_nlink(inode, nlink_tgid); 3136 pid_update_inode(task, inode); 3137 3138 d_set_d_op(dentry, &pid_dentry_operations); 3139 return d_splice_alias(inode, dentry); 3140 } 3141 3142 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3143 { 3144 struct task_struct *task; 3145 unsigned tgid; 3146 struct pid_namespace *ns; 3147 struct dentry *result = ERR_PTR(-ENOENT); 3148 3149 tgid = name_to_int(&dentry->d_name); 3150 if (tgid == ~0U) 3151 goto out; 3152 3153 ns = dentry->d_sb->s_fs_info; 3154 rcu_read_lock(); 3155 task = find_task_by_pid_ns(tgid, ns); 3156 if (task) 3157 get_task_struct(task); 3158 rcu_read_unlock(); 3159 if (!task) 3160 goto out; 3161 3162 result = proc_pid_instantiate(dentry, task, NULL); 3163 put_task_struct(task); 3164 out: 3165 return result; 3166 } 3167 3168 /* 3169 * Find the first task with tgid >= tgid 3170 * 3171 */ 3172 struct tgid_iter { 3173 unsigned int tgid; 3174 struct task_struct *task; 3175 }; 3176 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 3177 { 3178 struct pid *pid; 3179 3180 if (iter.task) 3181 put_task_struct(iter.task); 3182 rcu_read_lock(); 3183 retry: 3184 iter.task = NULL; 3185 pid = find_ge_pid(iter.tgid, ns); 3186 if (pid) { 3187 iter.tgid = pid_nr_ns(pid, ns); 3188 iter.task = pid_task(pid, PIDTYPE_PID); 3189 /* What we to know is if the pid we have find is the 3190 * pid of a thread_group_leader. Testing for task 3191 * being a thread_group_leader is the obvious thing 3192 * todo but there is a window when it fails, due to 3193 * the pid transfer logic in de_thread. 3194 * 3195 * So we perform the straight forward test of seeing 3196 * if the pid we have found is the pid of a thread 3197 * group leader, and don't worry if the task we have 3198 * found doesn't happen to be a thread group leader. 3199 * As we don't care in the case of readdir. 3200 */ 3201 if (!iter.task || !has_group_leader_pid(iter.task)) { 3202 iter.tgid += 1; 3203 goto retry; 3204 } 3205 get_task_struct(iter.task); 3206 } 3207 rcu_read_unlock(); 3208 return iter; 3209 } 3210 3211 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) 3212 3213 /* for the /proc/ directory itself, after non-process stuff has been done */ 3214 int proc_pid_readdir(struct file *file, struct dir_context *ctx) 3215 { 3216 struct tgid_iter iter; 3217 struct pid_namespace *ns = proc_pid_ns(file_inode(file)); 3218 loff_t pos = ctx->pos; 3219 3220 if (pos >= PID_MAX_LIMIT + TGID_OFFSET) 3221 return 0; 3222 3223 if (pos == TGID_OFFSET - 2) { 3224 struct inode *inode = d_inode(ns->proc_self); 3225 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK)) 3226 return 0; 3227 ctx->pos = pos = pos + 1; 3228 } 3229 if (pos == TGID_OFFSET - 1) { 3230 struct inode *inode = d_inode(ns->proc_thread_self); 3231 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK)) 3232 return 0; 3233 ctx->pos = pos = pos + 1; 3234 } 3235 iter.tgid = pos - TGID_OFFSET; 3236 iter.task = NULL; 3237 for (iter = next_tgid(ns, iter); 3238 iter.task; 3239 iter.tgid += 1, iter = next_tgid(ns, iter)) { 3240 char name[10 + 1]; 3241 unsigned int len; 3242 3243 cond_resched(); 3244 if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE)) 3245 continue; 3246 3247 len = snprintf(name, sizeof(name), "%u", iter.tgid); 3248 ctx->pos = iter.tgid + TGID_OFFSET; 3249 if (!proc_fill_cache(file, ctx, name, len, 3250 proc_pid_instantiate, iter.task, NULL)) { 3251 put_task_struct(iter.task); 3252 return 0; 3253 } 3254 } 3255 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; 3256 return 0; 3257 } 3258 3259 /* 3260 * proc_tid_comm_permission is a special permission function exclusively 3261 * used for the node /proc/<pid>/task/<tid>/comm. 3262 * It bypasses generic permission checks in the case where a task of the same 3263 * task group attempts to access the node. 3264 * The rationale behind this is that glibc and bionic access this node for 3265 * cross thread naming (pthread_set/getname_np(!self)). However, if 3266 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0, 3267 * which locks out the cross thread naming implementation. 3268 * This function makes sure that the node is always accessible for members of 3269 * same thread group. 3270 */ 3271 static int proc_tid_comm_permission(struct inode *inode, int mask) 3272 { 3273 bool is_same_tgroup; 3274 struct task_struct *task; 3275 3276 task = get_proc_task(inode); 3277 if (!task) 3278 return -ESRCH; 3279 is_same_tgroup = same_thread_group(current, task); 3280 put_task_struct(task); 3281 3282 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) { 3283 /* This file (/proc/<pid>/task/<tid>/comm) can always be 3284 * read or written by the members of the corresponding 3285 * thread group. 3286 */ 3287 return 0; 3288 } 3289 3290 return generic_permission(inode, mask); 3291 } 3292 3293 static const struct inode_operations proc_tid_comm_inode_operations = { 3294 .permission = proc_tid_comm_permission, 3295 }; 3296 3297 /* 3298 * Tasks 3299 */ 3300 static const struct pid_entry tid_base_stuff[] = { 3301 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 3302 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 3303 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 3304 #ifdef CONFIG_NET 3305 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 3306 #endif 3307 REG("environ", S_IRUSR, proc_environ_operations), 3308 REG("auxv", S_IRUSR, proc_auxv_operations), 3309 ONE("status", S_IRUGO, proc_pid_status), 3310 ONE("personality", S_IRUSR, proc_pid_personality), 3311 ONE("limits", S_IRUGO, proc_pid_limits), 3312 #ifdef CONFIG_SCHED_DEBUG 3313 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 3314 #endif 3315 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR, 3316 &proc_tid_comm_inode_operations, 3317 &proc_pid_set_comm_operations, {}), 3318 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 3319 ONE("syscall", S_IRUSR, proc_pid_syscall), 3320 #endif 3321 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 3322 ONE("stat", S_IRUGO, proc_tid_stat), 3323 ONE("statm", S_IRUGO, proc_pid_statm), 3324 REG("maps", S_IRUGO, proc_pid_maps_operations), 3325 #ifdef CONFIG_PROC_CHILDREN 3326 REG("children", S_IRUGO, proc_tid_children_operations), 3327 #endif 3328 #ifdef CONFIG_NUMA 3329 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 3330 #endif 3331 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 3332 LNK("cwd", proc_cwd_link), 3333 LNK("root", proc_root_link), 3334 LNK("exe", proc_exe_link), 3335 REG("mounts", S_IRUGO, proc_mounts_operations), 3336 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 3337 #ifdef CONFIG_PROC_PAGE_MONITOR 3338 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 3339 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 3340 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations), 3341 REG("pagemap", S_IRUSR, proc_pagemap_operations), 3342 #endif 3343 #ifdef CONFIG_SECURITY 3344 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 3345 #endif 3346 #ifdef CONFIG_KALLSYMS 3347 ONE("wchan", S_IRUGO, proc_pid_wchan), 3348 #endif 3349 #ifdef CONFIG_STACKTRACE 3350 ONE("stack", S_IRUSR, proc_pid_stack), 3351 #endif 3352 #ifdef CONFIG_SCHED_INFO 3353 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 3354 #endif 3355 #ifdef CONFIG_LATENCYTOP 3356 REG("latency", S_IRUGO, proc_lstats_operations), 3357 #endif 3358 #ifdef CONFIG_PROC_PID_CPUSET 3359 ONE("cpuset", S_IRUGO, proc_cpuset_show), 3360 #endif 3361 #ifdef CONFIG_CGROUPS 3362 ONE("cgroup", S_IRUGO, proc_cgroup_show), 3363 #endif 3364 ONE("oom_score", S_IRUGO, proc_oom_score), 3365 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 3366 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 3367 #ifdef CONFIG_AUDITSYSCALL 3368 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 3369 REG("sessionid", S_IRUGO, proc_sessionid_operations), 3370 #endif 3371 #ifdef CONFIG_FAULT_INJECTION 3372 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 3373 REG("fail-nth", 0644, proc_fail_nth_operations), 3374 #endif 3375 #ifdef CONFIG_TASK_IO_ACCOUNTING 3376 ONE("io", S_IRUSR, proc_tid_io_accounting), 3377 #endif 3378 #ifdef CONFIG_USER_NS 3379 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 3380 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 3381 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 3382 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 3383 #endif 3384 #ifdef CONFIG_LIVEPATCH 3385 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 3386 #endif 3387 }; 3388 3389 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) 3390 { 3391 return proc_pident_readdir(file, ctx, 3392 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3393 } 3394 3395 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3396 { 3397 return proc_pident_lookup(dir, dentry, 3398 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3399 } 3400 3401 static const struct file_operations proc_tid_base_operations = { 3402 .read = generic_read_dir, 3403 .iterate_shared = proc_tid_base_readdir, 3404 .llseek = generic_file_llseek, 3405 }; 3406 3407 static const struct inode_operations proc_tid_base_inode_operations = { 3408 .lookup = proc_tid_base_lookup, 3409 .getattr = pid_getattr, 3410 .setattr = proc_setattr, 3411 }; 3412 3413 static struct dentry *proc_task_instantiate(struct dentry *dentry, 3414 struct task_struct *task, const void *ptr) 3415 { 3416 struct inode *inode; 3417 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); 3418 if (!inode) 3419 return ERR_PTR(-ENOENT); 3420 3421 inode->i_op = &proc_tid_base_inode_operations; 3422 inode->i_fop = &proc_tid_base_operations; 3423 inode->i_flags |= S_IMMUTABLE; 3424 3425 set_nlink(inode, nlink_tid); 3426 pid_update_inode(task, inode); 3427 3428 d_set_d_op(dentry, &pid_dentry_operations); 3429 return d_splice_alias(inode, dentry); 3430 } 3431 3432 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3433 { 3434 struct task_struct *task; 3435 struct task_struct *leader = get_proc_task(dir); 3436 unsigned tid; 3437 struct pid_namespace *ns; 3438 struct dentry *result = ERR_PTR(-ENOENT); 3439 3440 if (!leader) 3441 goto out_no_task; 3442 3443 tid = name_to_int(&dentry->d_name); 3444 if (tid == ~0U) 3445 goto out; 3446 3447 ns = dentry->d_sb->s_fs_info; 3448 rcu_read_lock(); 3449 task = find_task_by_pid_ns(tid, ns); 3450 if (task) 3451 get_task_struct(task); 3452 rcu_read_unlock(); 3453 if (!task) 3454 goto out; 3455 if (!same_thread_group(leader, task)) 3456 goto out_drop_task; 3457 3458 result = proc_task_instantiate(dentry, task, NULL); 3459 out_drop_task: 3460 put_task_struct(task); 3461 out: 3462 put_task_struct(leader); 3463 out_no_task: 3464 return result; 3465 } 3466 3467 /* 3468 * Find the first tid of a thread group to return to user space. 3469 * 3470 * Usually this is just the thread group leader, but if the users 3471 * buffer was too small or there was a seek into the middle of the 3472 * directory we have more work todo. 3473 * 3474 * In the case of a short read we start with find_task_by_pid. 3475 * 3476 * In the case of a seek we start with the leader and walk nr 3477 * threads past it. 3478 */ 3479 static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos, 3480 struct pid_namespace *ns) 3481 { 3482 struct task_struct *pos, *task; 3483 unsigned long nr = f_pos; 3484 3485 if (nr != f_pos) /* 32bit overflow? */ 3486 return NULL; 3487 3488 rcu_read_lock(); 3489 task = pid_task(pid, PIDTYPE_PID); 3490 if (!task) 3491 goto fail; 3492 3493 /* Attempt to start with the tid of a thread */ 3494 if (tid && nr) { 3495 pos = find_task_by_pid_ns(tid, ns); 3496 if (pos && same_thread_group(pos, task)) 3497 goto found; 3498 } 3499 3500 /* If nr exceeds the number of threads there is nothing todo */ 3501 if (nr >= get_nr_threads(task)) 3502 goto fail; 3503 3504 /* If we haven't found our starting place yet start 3505 * with the leader and walk nr threads forward. 3506 */ 3507 pos = task = task->group_leader; 3508 do { 3509 if (!nr--) 3510 goto found; 3511 } while_each_thread(task, pos); 3512 fail: 3513 pos = NULL; 3514 goto out; 3515 found: 3516 get_task_struct(pos); 3517 out: 3518 rcu_read_unlock(); 3519 return pos; 3520 } 3521 3522 /* 3523 * Find the next thread in the thread list. 3524 * Return NULL if there is an error or no next thread. 3525 * 3526 * The reference to the input task_struct is released. 3527 */ 3528 static struct task_struct *next_tid(struct task_struct *start) 3529 { 3530 struct task_struct *pos = NULL; 3531 rcu_read_lock(); 3532 if (pid_alive(start)) { 3533 pos = next_thread(start); 3534 if (thread_group_leader(pos)) 3535 pos = NULL; 3536 else 3537 get_task_struct(pos); 3538 } 3539 rcu_read_unlock(); 3540 put_task_struct(start); 3541 return pos; 3542 } 3543 3544 /* for the /proc/TGID/task/ directories */ 3545 static int proc_task_readdir(struct file *file, struct dir_context *ctx) 3546 { 3547 struct inode *inode = file_inode(file); 3548 struct task_struct *task; 3549 struct pid_namespace *ns; 3550 int tid; 3551 3552 if (proc_inode_is_dead(inode)) 3553 return -ENOENT; 3554 3555 if (!dir_emit_dots(file, ctx)) 3556 return 0; 3557 3558 /* f_version caches the tgid value that the last readdir call couldn't 3559 * return. lseek aka telldir automagically resets f_version to 0. 3560 */ 3561 ns = proc_pid_ns(inode); 3562 tid = (int)file->f_version; 3563 file->f_version = 0; 3564 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns); 3565 task; 3566 task = next_tid(task), ctx->pos++) { 3567 char name[10 + 1]; 3568 unsigned int len; 3569 tid = task_pid_nr_ns(task, ns); 3570 len = snprintf(name, sizeof(name), "%u", tid); 3571 if (!proc_fill_cache(file, ctx, name, len, 3572 proc_task_instantiate, task, NULL)) { 3573 /* returning this tgid failed, save it as the first 3574 * pid for the next readir call */ 3575 file->f_version = (u64)tid; 3576 put_task_struct(task); 3577 break; 3578 } 3579 } 3580 3581 return 0; 3582 } 3583 3584 static int proc_task_getattr(const struct path *path, struct kstat *stat, 3585 u32 request_mask, unsigned int query_flags) 3586 { 3587 struct inode *inode = d_inode(path->dentry); 3588 struct task_struct *p = get_proc_task(inode); 3589 generic_fillattr(inode, stat); 3590 3591 if (p) { 3592 stat->nlink += get_nr_threads(p); 3593 put_task_struct(p); 3594 } 3595 3596 return 0; 3597 } 3598 3599 static const struct inode_operations proc_task_inode_operations = { 3600 .lookup = proc_task_lookup, 3601 .getattr = proc_task_getattr, 3602 .setattr = proc_setattr, 3603 .permission = proc_pid_permission, 3604 }; 3605 3606 static const struct file_operations proc_task_operations = { 3607 .read = generic_read_dir, 3608 .iterate_shared = proc_task_readdir, 3609 .llseek = generic_file_llseek, 3610 }; 3611 3612 void __init set_proc_pid_nlink(void) 3613 { 3614 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3615 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3616 } 3617