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