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