1 /* 2 * linux/fs/proc/base.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * proc base directory handling functions 7 * 8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part. 9 * Instead of using magical inumbers to determine the kind of object 10 * we allocate and fill in-core inodes upon lookup. They don't even 11 * go into icache. We cache the reference to task_struct upon lookup too. 12 * Eventually it should become a filesystem in its own. We don't use the 13 * rest of procfs anymore. 14 * 15 * 16 * Changelog: 17 * 17-Jan-2005 18 * Allan Bezerra 19 * Bruna Moreira <bruna.moreira@indt.org.br> 20 * Edjard Mota <edjard.mota@indt.org.br> 21 * Ilias Biris <ilias.biris@indt.org.br> 22 * Mauricio Lin <mauricio.lin@indt.org.br> 23 * 24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 25 * 26 * A new process specific entry (smaps) included in /proc. It shows the 27 * size of rss for each memory area. The maps entry lacks information 28 * about physical memory size (rss) for each mapped file, i.e., 29 * rss information for executables and library files. 30 * This additional information is useful for any tools that need to know 31 * about physical memory consumption for a process specific library. 32 * 33 * Changelog: 34 * 21-Feb-2005 35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT 36 * Pud inclusion in the page table walking. 37 * 38 * ChangeLog: 39 * 10-Mar-2005 40 * 10LE Instituto Nokia de Tecnologia - INdT: 41 * A better way to walks through the page table as suggested by Hugh Dickins. 42 * 43 * Simo Piiroinen <simo.piiroinen@nokia.com>: 44 * Smaps information related to shared, private, clean and dirty pages. 45 * 46 * Paul Mundt <paul.mundt@nokia.com>: 47 * Overall revision about smaps. 48 */ 49 50 #include <linux/uaccess.h> 51 52 #include <linux/errno.h> 53 #include <linux/time.h> 54 #include <linux/proc_fs.h> 55 #include <linux/stat.h> 56 #include <linux/task_io_accounting_ops.h> 57 #include <linux/init.h> 58 #include <linux/capability.h> 59 #include <linux/file.h> 60 #include <linux/fdtable.h> 61 #include <linux/string.h> 62 #include <linux/seq_file.h> 63 #include <linux/namei.h> 64 #include <linux/mnt_namespace.h> 65 #include <linux/mm.h> 66 #include <linux/swap.h> 67 #include <linux/rcupdate.h> 68 #include <linux/kallsyms.h> 69 #include <linux/stacktrace.h> 70 #include <linux/resource.h> 71 #include <linux/module.h> 72 #include <linux/mount.h> 73 #include <linux/security.h> 74 #include <linux/ptrace.h> 75 #include <linux/tracehook.h> 76 #include <linux/printk.h> 77 #include <linux/cgroup.h> 78 #include <linux/cpuset.h> 79 #include <linux/audit.h> 80 #include <linux/poll.h> 81 #include <linux/nsproxy.h> 82 #include <linux/oom.h> 83 #include <linux/elf.h> 84 #include <linux/pid_namespace.h> 85 #include <linux/user_namespace.h> 86 #include <linux/fs_struct.h> 87 #include <linux/slab.h> 88 #include <linux/sched/autogroup.h> 89 #include <linux/sched/mm.h> 90 #include <linux/sched/coredump.h> 91 #include <linux/sched/debug.h> 92 #include <linux/sched/stat.h> 93 #include <linux/flex_array.h> 94 #include <linux/posix-timers.h> 95 #ifdef CONFIG_HARDWALL 96 #include <asm/hardwall.h> 97 #endif 98 #include <trace/events/oom.h> 99 #include "internal.h" 100 #include "fd.h" 101 102 /* NOTE: 103 * Implementing inode permission operations in /proc is almost 104 * certainly an error. Permission checks need to happen during 105 * each system call not at open time. The reason is that most of 106 * what we wish to check for permissions in /proc varies at runtime. 107 * 108 * The classic example of a problem is opening file descriptors 109 * in /proc for a task before it execs a suid executable. 110 */ 111 112 static u8 nlink_tid; 113 static u8 nlink_tgid; 114 115 struct pid_entry { 116 const char *name; 117 unsigned int len; 118 umode_t mode; 119 const struct inode_operations *iop; 120 const struct file_operations *fop; 121 union proc_op op; 122 }; 123 124 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 125 .name = (NAME), \ 126 .len = sizeof(NAME) - 1, \ 127 .mode = MODE, \ 128 .iop = IOP, \ 129 .fop = FOP, \ 130 .op = OP, \ 131 } 132 133 #define DIR(NAME, MODE, iops, fops) \ 134 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 135 #define LNK(NAME, get_link) \ 136 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 137 &proc_pid_link_inode_operations, NULL, \ 138 { .proc_get_link = get_link } ) 139 #define REG(NAME, MODE, fops) \ 140 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 141 #define ONE(NAME, MODE, show) \ 142 NOD(NAME, (S_IFREG|(MODE)), \ 143 NULL, &proc_single_file_operations, \ 144 { .proc_show = show } ) 145 146 /* 147 * Count the number of hardlinks for the pid_entry table, excluding the . 148 * and .. links. 149 */ 150 static unsigned int __init pid_entry_nlink(const struct pid_entry *entries, 151 unsigned int n) 152 { 153 unsigned int i; 154 unsigned int count; 155 156 count = 2; 157 for (i = 0; i < n; ++i) { 158 if (S_ISDIR(entries[i].mode)) 159 ++count; 160 } 161 162 return count; 163 } 164 165 static int get_task_root(struct task_struct *task, struct path *root) 166 { 167 int result = -ENOENT; 168 169 task_lock(task); 170 if (task->fs) { 171 get_fs_root(task->fs, root); 172 result = 0; 173 } 174 task_unlock(task); 175 return result; 176 } 177 178 static int proc_cwd_link(struct dentry *dentry, struct path *path) 179 { 180 struct task_struct *task = get_proc_task(d_inode(dentry)); 181 int result = -ENOENT; 182 183 if (task) { 184 task_lock(task); 185 if (task->fs) { 186 get_fs_pwd(task->fs, path); 187 result = 0; 188 } 189 task_unlock(task); 190 put_task_struct(task); 191 } 192 return result; 193 } 194 195 static int proc_root_link(struct dentry *dentry, struct path *path) 196 { 197 struct task_struct *task = get_proc_task(d_inode(dentry)); 198 int result = -ENOENT; 199 200 if (task) { 201 result = get_task_root(task, path); 202 put_task_struct(task); 203 } 204 return result; 205 } 206 207 static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf, 208 size_t _count, loff_t *pos) 209 { 210 struct task_struct *tsk; 211 struct mm_struct *mm; 212 char *page; 213 unsigned long count = _count; 214 unsigned long arg_start, arg_end, env_start, env_end; 215 unsigned long len1, len2, len; 216 unsigned long p; 217 char c; 218 ssize_t rv; 219 220 BUG_ON(*pos < 0); 221 222 tsk = get_proc_task(file_inode(file)); 223 if (!tsk) 224 return -ESRCH; 225 mm = get_task_mm(tsk); 226 put_task_struct(tsk); 227 if (!mm) 228 return 0; 229 /* Check if process spawned far enough to have cmdline. */ 230 if (!mm->env_end) { 231 rv = 0; 232 goto out_mmput; 233 } 234 235 page = (char *)__get_free_page(GFP_TEMPORARY); 236 if (!page) { 237 rv = -ENOMEM; 238 goto out_mmput; 239 } 240 241 down_read(&mm->mmap_sem); 242 arg_start = mm->arg_start; 243 arg_end = mm->arg_end; 244 env_start = mm->env_start; 245 env_end = mm->env_end; 246 up_read(&mm->mmap_sem); 247 248 BUG_ON(arg_start > arg_end); 249 BUG_ON(env_start > env_end); 250 251 len1 = arg_end - arg_start; 252 len2 = env_end - env_start; 253 254 /* Empty ARGV. */ 255 if (len1 == 0) { 256 rv = 0; 257 goto out_free_page; 258 } 259 /* 260 * Inherently racy -- command line shares address space 261 * with code and data. 262 */ 263 rv = access_remote_vm(mm, arg_end - 1, &c, 1, 0); 264 if (rv <= 0) 265 goto out_free_page; 266 267 rv = 0; 268 269 if (c == '\0') { 270 /* Command line (set of strings) occupies whole ARGV. */ 271 if (len1 <= *pos) 272 goto out_free_page; 273 274 p = arg_start + *pos; 275 len = len1 - *pos; 276 while (count > 0 && len > 0) { 277 unsigned int _count; 278 int nr_read; 279 280 _count = min3(count, len, PAGE_SIZE); 281 nr_read = access_remote_vm(mm, p, page, _count, 0); 282 if (nr_read < 0) 283 rv = nr_read; 284 if (nr_read <= 0) 285 goto out_free_page; 286 287 if (copy_to_user(buf, page, nr_read)) { 288 rv = -EFAULT; 289 goto out_free_page; 290 } 291 292 p += nr_read; 293 len -= nr_read; 294 buf += nr_read; 295 count -= nr_read; 296 rv += nr_read; 297 } 298 } else { 299 /* 300 * Command line (1 string) occupies ARGV and 301 * extends into ENVP. 302 */ 303 struct { 304 unsigned long p; 305 unsigned long len; 306 } cmdline[2] = { 307 { .p = arg_start, .len = len1 }, 308 { .p = env_start, .len = len2 }, 309 }; 310 loff_t pos1 = *pos; 311 unsigned int i; 312 313 i = 0; 314 while (i < 2 && pos1 >= cmdline[i].len) { 315 pos1 -= cmdline[i].len; 316 i++; 317 } 318 while (i < 2) { 319 p = cmdline[i].p + pos1; 320 len = cmdline[i].len - pos1; 321 while (count > 0 && len > 0) { 322 unsigned int _count, l; 323 int nr_read; 324 bool final; 325 326 _count = min3(count, len, PAGE_SIZE); 327 nr_read = access_remote_vm(mm, p, page, _count, 0); 328 if (nr_read < 0) 329 rv = nr_read; 330 if (nr_read <= 0) 331 goto out_free_page; 332 333 /* 334 * Command line can be shorter than whole ARGV 335 * even if last "marker" byte says it is not. 336 */ 337 final = false; 338 l = strnlen(page, nr_read); 339 if (l < nr_read) { 340 nr_read = l; 341 final = true; 342 } 343 344 if (copy_to_user(buf, page, nr_read)) { 345 rv = -EFAULT; 346 goto out_free_page; 347 } 348 349 p += nr_read; 350 len -= nr_read; 351 buf += nr_read; 352 count -= nr_read; 353 rv += nr_read; 354 355 if (final) 356 goto out_free_page; 357 } 358 359 /* Only first chunk can be read partially. */ 360 pos1 = 0; 361 i++; 362 } 363 } 364 365 out_free_page: 366 free_page((unsigned long)page); 367 out_mmput: 368 mmput(mm); 369 if (rv > 0) 370 *pos += rv; 371 return rv; 372 } 373 374 static const struct file_operations proc_pid_cmdline_ops = { 375 .read = proc_pid_cmdline_read, 376 .llseek = generic_file_llseek, 377 }; 378 379 #ifdef CONFIG_KALLSYMS 380 /* 381 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 382 * Returns the resolved symbol. If that fails, simply return the address. 383 */ 384 static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns, 385 struct pid *pid, struct task_struct *task) 386 { 387 unsigned long wchan; 388 char symname[KSYM_NAME_LEN]; 389 390 wchan = get_wchan(task); 391 392 if (wchan && ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS) 393 && !lookup_symbol_name(wchan, symname)) 394 seq_printf(m, "%s", symname); 395 else 396 seq_putc(m, '0'); 397 398 return 0; 399 } 400 #endif /* CONFIG_KALLSYMS */ 401 402 static int lock_trace(struct task_struct *task) 403 { 404 int err = mutex_lock_killable(&task->signal->cred_guard_mutex); 405 if (err) 406 return err; 407 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) { 408 mutex_unlock(&task->signal->cred_guard_mutex); 409 return -EPERM; 410 } 411 return 0; 412 } 413 414 static void unlock_trace(struct task_struct *task) 415 { 416 mutex_unlock(&task->signal->cred_guard_mutex); 417 } 418 419 #ifdef CONFIG_STACKTRACE 420 421 #define MAX_STACK_TRACE_DEPTH 64 422 423 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 424 struct pid *pid, struct task_struct *task) 425 { 426 struct stack_trace trace; 427 unsigned long *entries; 428 int err; 429 int i; 430 431 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL); 432 if (!entries) 433 return -ENOMEM; 434 435 trace.nr_entries = 0; 436 trace.max_entries = MAX_STACK_TRACE_DEPTH; 437 trace.entries = entries; 438 trace.skip = 0; 439 440 err = lock_trace(task); 441 if (!err) { 442 save_stack_trace_tsk(task, &trace); 443 444 for (i = 0; i < trace.nr_entries; i++) { 445 seq_printf(m, "[<%pK>] %pB\n", 446 (void *)entries[i], (void *)entries[i]); 447 } 448 unlock_trace(task); 449 } 450 kfree(entries); 451 452 return err; 453 } 454 #endif 455 456 #ifdef CONFIG_SCHED_INFO 457 /* 458 * Provides /proc/PID/schedstat 459 */ 460 static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, 461 struct pid *pid, struct task_struct *task) 462 { 463 if (unlikely(!sched_info_on())) 464 seq_printf(m, "0 0 0\n"); 465 else 466 seq_printf(m, "%llu %llu %lu\n", 467 (unsigned long long)task->se.sum_exec_runtime, 468 (unsigned long long)task->sched_info.run_delay, 469 task->sched_info.pcount); 470 471 return 0; 472 } 473 #endif 474 475 #ifdef CONFIG_LATENCYTOP 476 static int lstats_show_proc(struct seq_file *m, void *v) 477 { 478 int i; 479 struct inode *inode = m->private; 480 struct task_struct *task = get_proc_task(inode); 481 482 if (!task) 483 return -ESRCH; 484 seq_puts(m, "Latency Top version : v0.1\n"); 485 for (i = 0; i < 32; i++) { 486 struct latency_record *lr = &task->latency_record[i]; 487 if (lr->backtrace[0]) { 488 int q; 489 seq_printf(m, "%i %li %li", 490 lr->count, lr->time, lr->max); 491 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 492 unsigned long bt = lr->backtrace[q]; 493 if (!bt) 494 break; 495 if (bt == ULONG_MAX) 496 break; 497 seq_printf(m, " %ps", (void *)bt); 498 } 499 seq_putc(m, '\n'); 500 } 501 502 } 503 put_task_struct(task); 504 return 0; 505 } 506 507 static int lstats_open(struct inode *inode, struct file *file) 508 { 509 return single_open(file, lstats_show_proc, inode); 510 } 511 512 static ssize_t lstats_write(struct file *file, const char __user *buf, 513 size_t count, loff_t *offs) 514 { 515 struct task_struct *task = get_proc_task(file_inode(file)); 516 517 if (!task) 518 return -ESRCH; 519 clear_all_latency_tracing(task); 520 put_task_struct(task); 521 522 return count; 523 } 524 525 static const struct file_operations proc_lstats_operations = { 526 .open = lstats_open, 527 .read = seq_read, 528 .write = lstats_write, 529 .llseek = seq_lseek, 530 .release = single_release, 531 }; 532 533 #endif 534 535 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, 536 struct pid *pid, struct task_struct *task) 537 { 538 unsigned long totalpages = totalram_pages + total_swap_pages; 539 unsigned long points = 0; 540 541 points = oom_badness(task, NULL, NULL, totalpages) * 542 1000 / totalpages; 543 seq_printf(m, "%lu\n", points); 544 545 return 0; 546 } 547 548 struct limit_names { 549 const char *name; 550 const char *unit; 551 }; 552 553 static const struct limit_names lnames[RLIM_NLIMITS] = { 554 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 555 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 556 [RLIMIT_DATA] = {"Max data size", "bytes"}, 557 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 558 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 559 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 560 [RLIMIT_NPROC] = {"Max processes", "processes"}, 561 [RLIMIT_NOFILE] = {"Max open files", "files"}, 562 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 563 [RLIMIT_AS] = {"Max address space", "bytes"}, 564 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 565 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 566 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 567 [RLIMIT_NICE] = {"Max nice priority", NULL}, 568 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 569 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 570 }; 571 572 /* Display limits for a process */ 573 static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns, 574 struct pid *pid, struct task_struct *task) 575 { 576 unsigned int i; 577 unsigned long flags; 578 579 struct rlimit rlim[RLIM_NLIMITS]; 580 581 if (!lock_task_sighand(task, &flags)) 582 return 0; 583 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 584 unlock_task_sighand(task, &flags); 585 586 /* 587 * print the file header 588 */ 589 seq_printf(m, "%-25s %-20s %-20s %-10s\n", 590 "Limit", "Soft Limit", "Hard Limit", "Units"); 591 592 for (i = 0; i < RLIM_NLIMITS; i++) { 593 if (rlim[i].rlim_cur == RLIM_INFINITY) 594 seq_printf(m, "%-25s %-20s ", 595 lnames[i].name, "unlimited"); 596 else 597 seq_printf(m, "%-25s %-20lu ", 598 lnames[i].name, rlim[i].rlim_cur); 599 600 if (rlim[i].rlim_max == RLIM_INFINITY) 601 seq_printf(m, "%-20s ", "unlimited"); 602 else 603 seq_printf(m, "%-20lu ", rlim[i].rlim_max); 604 605 if (lnames[i].unit) 606 seq_printf(m, "%-10s\n", lnames[i].unit); 607 else 608 seq_putc(m, '\n'); 609 } 610 611 return 0; 612 } 613 614 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 615 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns, 616 struct pid *pid, struct task_struct *task) 617 { 618 long nr; 619 unsigned long args[6], sp, pc; 620 int res; 621 622 res = lock_trace(task); 623 if (res) 624 return res; 625 626 if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) 627 seq_puts(m, "running\n"); 628 else if (nr < 0) 629 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc); 630 else 631 seq_printf(m, 632 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 633 nr, 634 args[0], args[1], args[2], args[3], args[4], args[5], 635 sp, pc); 636 unlock_trace(task); 637 638 return 0; 639 } 640 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 641 642 /************************************************************************/ 643 /* Here the fs part begins */ 644 /************************************************************************/ 645 646 /* permission checks */ 647 static int proc_fd_access_allowed(struct inode *inode) 648 { 649 struct task_struct *task; 650 int allowed = 0; 651 /* Allow access to a task's file descriptors if it is us or we 652 * may use ptrace attach to the process and find out that 653 * information. 654 */ 655 task = get_proc_task(inode); 656 if (task) { 657 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 658 put_task_struct(task); 659 } 660 return allowed; 661 } 662 663 int proc_setattr(struct dentry *dentry, struct iattr *attr) 664 { 665 int error; 666 struct inode *inode = d_inode(dentry); 667 668 if (attr->ia_valid & ATTR_MODE) 669 return -EPERM; 670 671 error = setattr_prepare(dentry, attr); 672 if (error) 673 return error; 674 675 setattr_copy(inode, attr); 676 mark_inode_dirty(inode); 677 return 0; 678 } 679 680 /* 681 * May current process learn task's sched/cmdline info (for hide_pid_min=1) 682 * or euid/egid (for hide_pid_min=2)? 683 */ 684 static bool has_pid_permissions(struct pid_namespace *pid, 685 struct task_struct *task, 686 int hide_pid_min) 687 { 688 if (pid->hide_pid < hide_pid_min) 689 return true; 690 if (in_group_p(pid->pid_gid)) 691 return true; 692 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS); 693 } 694 695 696 static int proc_pid_permission(struct inode *inode, int mask) 697 { 698 struct pid_namespace *pid = inode->i_sb->s_fs_info; 699 struct task_struct *task; 700 bool has_perms; 701 702 task = get_proc_task(inode); 703 if (!task) 704 return -ESRCH; 705 has_perms = has_pid_permissions(pid, task, HIDEPID_NO_ACCESS); 706 put_task_struct(task); 707 708 if (!has_perms) { 709 if (pid->hide_pid == HIDEPID_INVISIBLE) { 710 /* 711 * Let's make getdents(), stat(), and open() 712 * consistent with each other. If a process 713 * may not stat() a file, it shouldn't be seen 714 * in procfs at all. 715 */ 716 return -ENOENT; 717 } 718 719 return -EPERM; 720 } 721 return generic_permission(inode, mask); 722 } 723 724 725 726 static const struct inode_operations proc_def_inode_operations = { 727 .setattr = proc_setattr, 728 }; 729 730 static int proc_single_show(struct seq_file *m, void *v) 731 { 732 struct inode *inode = m->private; 733 struct pid_namespace *ns; 734 struct pid *pid; 735 struct task_struct *task; 736 int ret; 737 738 ns = inode->i_sb->s_fs_info; 739 pid = proc_pid(inode); 740 task = get_pid_task(pid, PIDTYPE_PID); 741 if (!task) 742 return -ESRCH; 743 744 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 745 746 put_task_struct(task); 747 return ret; 748 } 749 750 static int proc_single_open(struct inode *inode, struct file *filp) 751 { 752 return single_open(filp, proc_single_show, inode); 753 } 754 755 static const struct file_operations proc_single_file_operations = { 756 .open = proc_single_open, 757 .read = seq_read, 758 .llseek = seq_lseek, 759 .release = single_release, 760 }; 761 762 763 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode) 764 { 765 struct task_struct *task = get_proc_task(inode); 766 struct mm_struct *mm = ERR_PTR(-ESRCH); 767 768 if (task) { 769 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS); 770 put_task_struct(task); 771 772 if (!IS_ERR_OR_NULL(mm)) { 773 /* ensure this mm_struct can't be freed */ 774 mmgrab(mm); 775 /* but do not pin its memory */ 776 mmput(mm); 777 } 778 } 779 780 return mm; 781 } 782 783 static int __mem_open(struct inode *inode, struct file *file, unsigned int mode) 784 { 785 struct mm_struct *mm = proc_mem_open(inode, mode); 786 787 if (IS_ERR(mm)) 788 return PTR_ERR(mm); 789 790 file->private_data = mm; 791 return 0; 792 } 793 794 static int mem_open(struct inode *inode, struct file *file) 795 { 796 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH); 797 798 /* OK to pass negative loff_t, we can catch out-of-range */ 799 file->f_mode |= FMODE_UNSIGNED_OFFSET; 800 801 return ret; 802 } 803 804 static ssize_t mem_rw(struct file *file, char __user *buf, 805 size_t count, loff_t *ppos, int write) 806 { 807 struct mm_struct *mm = file->private_data; 808 unsigned long addr = *ppos; 809 ssize_t copied; 810 char *page; 811 unsigned int flags; 812 813 if (!mm) 814 return 0; 815 816 page = (char *)__get_free_page(GFP_TEMPORARY); 817 if (!page) 818 return -ENOMEM; 819 820 copied = 0; 821 if (!mmget_not_zero(mm)) 822 goto free; 823 824 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0); 825 826 while (count > 0) { 827 int this_len = min_t(int, count, PAGE_SIZE); 828 829 if (write && copy_from_user(page, buf, this_len)) { 830 copied = -EFAULT; 831 break; 832 } 833 834 this_len = access_remote_vm(mm, addr, page, this_len, flags); 835 if (!this_len) { 836 if (!copied) 837 copied = -EIO; 838 break; 839 } 840 841 if (!write && copy_to_user(buf, page, this_len)) { 842 copied = -EFAULT; 843 break; 844 } 845 846 buf += this_len; 847 addr += this_len; 848 copied += this_len; 849 count -= this_len; 850 } 851 *ppos = addr; 852 853 mmput(mm); 854 free: 855 free_page((unsigned long) page); 856 return copied; 857 } 858 859 static ssize_t mem_read(struct file *file, char __user *buf, 860 size_t count, loff_t *ppos) 861 { 862 return mem_rw(file, buf, count, ppos, 0); 863 } 864 865 static ssize_t mem_write(struct file *file, const char __user *buf, 866 size_t count, loff_t *ppos) 867 { 868 return mem_rw(file, (char __user*)buf, count, ppos, 1); 869 } 870 871 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 872 { 873 switch (orig) { 874 case 0: 875 file->f_pos = offset; 876 break; 877 case 1: 878 file->f_pos += offset; 879 break; 880 default: 881 return -EINVAL; 882 } 883 force_successful_syscall_return(); 884 return file->f_pos; 885 } 886 887 static int mem_release(struct inode *inode, struct file *file) 888 { 889 struct mm_struct *mm = file->private_data; 890 if (mm) 891 mmdrop(mm); 892 return 0; 893 } 894 895 static const struct file_operations proc_mem_operations = { 896 .llseek = mem_lseek, 897 .read = mem_read, 898 .write = mem_write, 899 .open = mem_open, 900 .release = mem_release, 901 }; 902 903 static int environ_open(struct inode *inode, struct file *file) 904 { 905 return __mem_open(inode, file, PTRACE_MODE_READ); 906 } 907 908 static ssize_t environ_read(struct file *file, char __user *buf, 909 size_t count, loff_t *ppos) 910 { 911 char *page; 912 unsigned long src = *ppos; 913 int ret = 0; 914 struct mm_struct *mm = file->private_data; 915 unsigned long env_start, env_end; 916 917 /* Ensure the process spawned far enough to have an environment. */ 918 if (!mm || !mm->env_end) 919 return 0; 920 921 page = (char *)__get_free_page(GFP_TEMPORARY); 922 if (!page) 923 return -ENOMEM; 924 925 ret = 0; 926 if (!mmget_not_zero(mm)) 927 goto free; 928 929 down_read(&mm->mmap_sem); 930 env_start = mm->env_start; 931 env_end = mm->env_end; 932 up_read(&mm->mmap_sem); 933 934 while (count > 0) { 935 size_t this_len, max_len; 936 int retval; 937 938 if (src >= (env_end - env_start)) 939 break; 940 941 this_len = env_end - (env_start + src); 942 943 max_len = min_t(size_t, PAGE_SIZE, count); 944 this_len = min(max_len, this_len); 945 946 retval = access_remote_vm(mm, (env_start + src), page, this_len, 0); 947 948 if (retval <= 0) { 949 ret = retval; 950 break; 951 } 952 953 if (copy_to_user(buf, page, retval)) { 954 ret = -EFAULT; 955 break; 956 } 957 958 ret += retval; 959 src += retval; 960 buf += retval; 961 count -= retval; 962 } 963 *ppos = src; 964 mmput(mm); 965 966 free: 967 free_page((unsigned long) page); 968 return ret; 969 } 970 971 static const struct file_operations proc_environ_operations = { 972 .open = environ_open, 973 .read = environ_read, 974 .llseek = generic_file_llseek, 975 .release = mem_release, 976 }; 977 978 static int auxv_open(struct inode *inode, struct file *file) 979 { 980 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS); 981 } 982 983 static ssize_t auxv_read(struct file *file, char __user *buf, 984 size_t count, loff_t *ppos) 985 { 986 struct mm_struct *mm = file->private_data; 987 unsigned int nwords = 0; 988 989 if (!mm) 990 return 0; 991 do { 992 nwords += 2; 993 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 994 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv, 995 nwords * sizeof(mm->saved_auxv[0])); 996 } 997 998 static const struct file_operations proc_auxv_operations = { 999 .open = auxv_open, 1000 .read = auxv_read, 1001 .llseek = generic_file_llseek, 1002 .release = mem_release, 1003 }; 1004 1005 static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count, 1006 loff_t *ppos) 1007 { 1008 struct task_struct *task = get_proc_task(file_inode(file)); 1009 char buffer[PROC_NUMBUF]; 1010 int oom_adj = OOM_ADJUST_MIN; 1011 size_t len; 1012 1013 if (!task) 1014 return -ESRCH; 1015 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX) 1016 oom_adj = OOM_ADJUST_MAX; 1017 else 1018 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) / 1019 OOM_SCORE_ADJ_MAX; 1020 put_task_struct(task); 1021 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj); 1022 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1023 } 1024 1025 static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) 1026 { 1027 static DEFINE_MUTEX(oom_adj_mutex); 1028 struct mm_struct *mm = NULL; 1029 struct task_struct *task; 1030 int err = 0; 1031 1032 task = get_proc_task(file_inode(file)); 1033 if (!task) 1034 return -ESRCH; 1035 1036 mutex_lock(&oom_adj_mutex); 1037 if (legacy) { 1038 if (oom_adj < task->signal->oom_score_adj && 1039 !capable(CAP_SYS_RESOURCE)) { 1040 err = -EACCES; 1041 goto err_unlock; 1042 } 1043 /* 1044 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use 1045 * /proc/pid/oom_score_adj instead. 1046 */ 1047 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", 1048 current->comm, task_pid_nr(current), task_pid_nr(task), 1049 task_pid_nr(task)); 1050 } else { 1051 if ((short)oom_adj < task->signal->oom_score_adj_min && 1052 !capable(CAP_SYS_RESOURCE)) { 1053 err = -EACCES; 1054 goto err_unlock; 1055 } 1056 } 1057 1058 /* 1059 * Make sure we will check other processes sharing the mm if this is 1060 * not vfrok which wants its own oom_score_adj. 1061 * pin the mm so it doesn't go away and get reused after task_unlock 1062 */ 1063 if (!task->vfork_done) { 1064 struct task_struct *p = find_lock_task_mm(task); 1065 1066 if (p) { 1067 if (atomic_read(&p->mm->mm_users) > 1) { 1068 mm = p->mm; 1069 mmgrab(mm); 1070 } 1071 task_unlock(p); 1072 } 1073 } 1074 1075 task->signal->oom_score_adj = oom_adj; 1076 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1077 task->signal->oom_score_adj_min = (short)oom_adj; 1078 trace_oom_score_adj_update(task); 1079 1080 if (mm) { 1081 struct task_struct *p; 1082 1083 rcu_read_lock(); 1084 for_each_process(p) { 1085 if (same_thread_group(task, p)) 1086 continue; 1087 1088 /* do not touch kernel threads or the global init */ 1089 if (p->flags & PF_KTHREAD || is_global_init(p)) 1090 continue; 1091 1092 task_lock(p); 1093 if (!p->vfork_done && process_shares_mm(p, mm)) { 1094 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", 1095 task_pid_nr(p), p->comm, 1096 p->signal->oom_score_adj, oom_adj, 1097 task_pid_nr(task), task->comm); 1098 p->signal->oom_score_adj = oom_adj; 1099 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) 1100 p->signal->oom_score_adj_min = (short)oom_adj; 1101 } 1102 task_unlock(p); 1103 } 1104 rcu_read_unlock(); 1105 mmdrop(mm); 1106 } 1107 err_unlock: 1108 mutex_unlock(&oom_adj_mutex); 1109 put_task_struct(task); 1110 return err; 1111 } 1112 1113 /* 1114 * /proc/pid/oom_adj exists solely for backwards compatibility with previous 1115 * kernels. The effective policy is defined by oom_score_adj, which has a 1116 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly. 1117 * Values written to oom_adj are simply mapped linearly to oom_score_adj. 1118 * Processes that become oom disabled via oom_adj will still be oom disabled 1119 * with this implementation. 1120 * 1121 * oom_adj cannot be removed since existing userspace binaries use it. 1122 */ 1123 static ssize_t oom_adj_write(struct file *file, const char __user *buf, 1124 size_t count, loff_t *ppos) 1125 { 1126 char buffer[PROC_NUMBUF]; 1127 int oom_adj; 1128 int err; 1129 1130 memset(buffer, 0, sizeof(buffer)); 1131 if (count > sizeof(buffer) - 1) 1132 count = sizeof(buffer) - 1; 1133 if (copy_from_user(buffer, buf, count)) { 1134 err = -EFAULT; 1135 goto out; 1136 } 1137 1138 err = kstrtoint(strstrip(buffer), 0, &oom_adj); 1139 if (err) 1140 goto out; 1141 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) && 1142 oom_adj != OOM_DISABLE) { 1143 err = -EINVAL; 1144 goto out; 1145 } 1146 1147 /* 1148 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum 1149 * value is always attainable. 1150 */ 1151 if (oom_adj == OOM_ADJUST_MAX) 1152 oom_adj = OOM_SCORE_ADJ_MAX; 1153 else 1154 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; 1155 1156 err = __set_oom_adj(file, oom_adj, true); 1157 out: 1158 return err < 0 ? err : count; 1159 } 1160 1161 static const struct file_operations proc_oom_adj_operations = { 1162 .read = oom_adj_read, 1163 .write = oom_adj_write, 1164 .llseek = generic_file_llseek, 1165 }; 1166 1167 static ssize_t oom_score_adj_read(struct file *file, char __user *buf, 1168 size_t count, loff_t *ppos) 1169 { 1170 struct task_struct *task = get_proc_task(file_inode(file)); 1171 char buffer[PROC_NUMBUF]; 1172 short oom_score_adj = OOM_SCORE_ADJ_MIN; 1173 size_t len; 1174 1175 if (!task) 1176 return -ESRCH; 1177 oom_score_adj = task->signal->oom_score_adj; 1178 put_task_struct(task); 1179 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj); 1180 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1181 } 1182 1183 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, 1184 size_t count, loff_t *ppos) 1185 { 1186 char buffer[PROC_NUMBUF]; 1187 int oom_score_adj; 1188 int err; 1189 1190 memset(buffer, 0, sizeof(buffer)); 1191 if (count > sizeof(buffer) - 1) 1192 count = sizeof(buffer) - 1; 1193 if (copy_from_user(buffer, buf, count)) { 1194 err = -EFAULT; 1195 goto out; 1196 } 1197 1198 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj); 1199 if (err) 1200 goto out; 1201 if (oom_score_adj < OOM_SCORE_ADJ_MIN || 1202 oom_score_adj > OOM_SCORE_ADJ_MAX) { 1203 err = -EINVAL; 1204 goto out; 1205 } 1206 1207 err = __set_oom_adj(file, oom_score_adj, false); 1208 out: 1209 return err < 0 ? err : count; 1210 } 1211 1212 static const struct file_operations proc_oom_score_adj_operations = { 1213 .read = oom_score_adj_read, 1214 .write = oom_score_adj_write, 1215 .llseek = default_llseek, 1216 }; 1217 1218 #ifdef CONFIG_AUDITSYSCALL 1219 #define TMPBUFLEN 11 1220 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1221 size_t count, loff_t *ppos) 1222 { 1223 struct inode * inode = file_inode(file); 1224 struct task_struct *task = get_proc_task(inode); 1225 ssize_t length; 1226 char tmpbuf[TMPBUFLEN]; 1227 1228 if (!task) 1229 return -ESRCH; 1230 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1231 from_kuid(file->f_cred->user_ns, 1232 audit_get_loginuid(task))); 1233 put_task_struct(task); 1234 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1235 } 1236 1237 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1238 size_t count, loff_t *ppos) 1239 { 1240 struct inode * inode = file_inode(file); 1241 uid_t loginuid; 1242 kuid_t kloginuid; 1243 int rv; 1244 1245 rcu_read_lock(); 1246 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 1247 rcu_read_unlock(); 1248 return -EPERM; 1249 } 1250 rcu_read_unlock(); 1251 1252 if (*ppos != 0) { 1253 /* No partial writes. */ 1254 return -EINVAL; 1255 } 1256 1257 rv = kstrtou32_from_user(buf, count, 10, &loginuid); 1258 if (rv < 0) 1259 return rv; 1260 1261 /* is userspace tring to explicitly UNSET the loginuid? */ 1262 if (loginuid == AUDIT_UID_UNSET) { 1263 kloginuid = INVALID_UID; 1264 } else { 1265 kloginuid = make_kuid(file->f_cred->user_ns, loginuid); 1266 if (!uid_valid(kloginuid)) 1267 return -EINVAL; 1268 } 1269 1270 rv = audit_set_loginuid(kloginuid); 1271 if (rv < 0) 1272 return rv; 1273 return count; 1274 } 1275 1276 static const struct file_operations proc_loginuid_operations = { 1277 .read = proc_loginuid_read, 1278 .write = proc_loginuid_write, 1279 .llseek = generic_file_llseek, 1280 }; 1281 1282 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1283 size_t count, loff_t *ppos) 1284 { 1285 struct inode * inode = file_inode(file); 1286 struct task_struct *task = get_proc_task(inode); 1287 ssize_t length; 1288 char tmpbuf[TMPBUFLEN]; 1289 1290 if (!task) 1291 return -ESRCH; 1292 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1293 audit_get_sessionid(task)); 1294 put_task_struct(task); 1295 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1296 } 1297 1298 static const struct file_operations proc_sessionid_operations = { 1299 .read = proc_sessionid_read, 1300 .llseek = generic_file_llseek, 1301 }; 1302 #endif 1303 1304 #ifdef CONFIG_FAULT_INJECTION 1305 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1306 size_t count, loff_t *ppos) 1307 { 1308 struct task_struct *task = get_proc_task(file_inode(file)); 1309 char buffer[PROC_NUMBUF]; 1310 size_t len; 1311 int make_it_fail; 1312 1313 if (!task) 1314 return -ESRCH; 1315 make_it_fail = task->make_it_fail; 1316 put_task_struct(task); 1317 1318 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1319 1320 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1321 } 1322 1323 static ssize_t proc_fault_inject_write(struct file * file, 1324 const char __user * buf, size_t count, loff_t *ppos) 1325 { 1326 struct task_struct *task; 1327 char buffer[PROC_NUMBUF]; 1328 int make_it_fail; 1329 int rv; 1330 1331 if (!capable(CAP_SYS_RESOURCE)) 1332 return -EPERM; 1333 memset(buffer, 0, sizeof(buffer)); 1334 if (count > sizeof(buffer) - 1) 1335 count = sizeof(buffer) - 1; 1336 if (copy_from_user(buffer, buf, count)) 1337 return -EFAULT; 1338 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail); 1339 if (rv < 0) 1340 return rv; 1341 if (make_it_fail < 0 || make_it_fail > 1) 1342 return -EINVAL; 1343 1344 task = get_proc_task(file_inode(file)); 1345 if (!task) 1346 return -ESRCH; 1347 task->make_it_fail = make_it_fail; 1348 put_task_struct(task); 1349 1350 return count; 1351 } 1352 1353 static const struct file_operations proc_fault_inject_operations = { 1354 .read = proc_fault_inject_read, 1355 .write = proc_fault_inject_write, 1356 .llseek = generic_file_llseek, 1357 }; 1358 1359 static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf, 1360 size_t count, loff_t *ppos) 1361 { 1362 struct task_struct *task; 1363 int err, n; 1364 1365 task = get_proc_task(file_inode(file)); 1366 if (!task) 1367 return -ESRCH; 1368 put_task_struct(task); 1369 if (task != current) 1370 return -EPERM; 1371 err = kstrtoint_from_user(buf, count, 10, &n); 1372 if (err) 1373 return err; 1374 if (n < 0 || n == INT_MAX) 1375 return -EINVAL; 1376 current->fail_nth = n + 1; 1377 return count; 1378 } 1379 1380 static ssize_t proc_fail_nth_read(struct file *file, char __user *buf, 1381 size_t count, loff_t *ppos) 1382 { 1383 struct task_struct *task; 1384 int err; 1385 1386 task = get_proc_task(file_inode(file)); 1387 if (!task) 1388 return -ESRCH; 1389 put_task_struct(task); 1390 if (task != current) 1391 return -EPERM; 1392 if (count < 1) 1393 return -EINVAL; 1394 err = put_user((char)(current->fail_nth ? 'N' : 'Y'), buf); 1395 if (err) 1396 return err; 1397 current->fail_nth = 0; 1398 return 1; 1399 } 1400 1401 static const struct file_operations proc_fail_nth_operations = { 1402 .read = proc_fail_nth_read, 1403 .write = proc_fail_nth_write, 1404 }; 1405 #endif 1406 1407 1408 #ifdef CONFIG_SCHED_DEBUG 1409 /* 1410 * Print out various scheduling related per-task fields: 1411 */ 1412 static int sched_show(struct seq_file *m, void *v) 1413 { 1414 struct inode *inode = m->private; 1415 struct task_struct *p; 1416 1417 p = get_proc_task(inode); 1418 if (!p) 1419 return -ESRCH; 1420 proc_sched_show_task(p, m); 1421 1422 put_task_struct(p); 1423 1424 return 0; 1425 } 1426 1427 static ssize_t 1428 sched_write(struct file *file, const char __user *buf, 1429 size_t count, loff_t *offset) 1430 { 1431 struct inode *inode = file_inode(file); 1432 struct task_struct *p; 1433 1434 p = get_proc_task(inode); 1435 if (!p) 1436 return -ESRCH; 1437 proc_sched_set_task(p); 1438 1439 put_task_struct(p); 1440 1441 return count; 1442 } 1443 1444 static int sched_open(struct inode *inode, struct file *filp) 1445 { 1446 return single_open(filp, sched_show, inode); 1447 } 1448 1449 static const struct file_operations proc_pid_sched_operations = { 1450 .open = sched_open, 1451 .read = seq_read, 1452 .write = sched_write, 1453 .llseek = seq_lseek, 1454 .release = single_release, 1455 }; 1456 1457 #endif 1458 1459 #ifdef CONFIG_SCHED_AUTOGROUP 1460 /* 1461 * Print out autogroup related information: 1462 */ 1463 static int sched_autogroup_show(struct seq_file *m, void *v) 1464 { 1465 struct inode *inode = m->private; 1466 struct task_struct *p; 1467 1468 p = get_proc_task(inode); 1469 if (!p) 1470 return -ESRCH; 1471 proc_sched_autogroup_show_task(p, m); 1472 1473 put_task_struct(p); 1474 1475 return 0; 1476 } 1477 1478 static ssize_t 1479 sched_autogroup_write(struct file *file, const char __user *buf, 1480 size_t count, loff_t *offset) 1481 { 1482 struct inode *inode = file_inode(file); 1483 struct task_struct *p; 1484 char buffer[PROC_NUMBUF]; 1485 int nice; 1486 int err; 1487 1488 memset(buffer, 0, sizeof(buffer)); 1489 if (count > sizeof(buffer) - 1) 1490 count = sizeof(buffer) - 1; 1491 if (copy_from_user(buffer, buf, count)) 1492 return -EFAULT; 1493 1494 err = kstrtoint(strstrip(buffer), 0, &nice); 1495 if (err < 0) 1496 return err; 1497 1498 p = get_proc_task(inode); 1499 if (!p) 1500 return -ESRCH; 1501 1502 err = proc_sched_autogroup_set_nice(p, nice); 1503 if (err) 1504 count = err; 1505 1506 put_task_struct(p); 1507 1508 return count; 1509 } 1510 1511 static int sched_autogroup_open(struct inode *inode, struct file *filp) 1512 { 1513 int ret; 1514 1515 ret = single_open(filp, sched_autogroup_show, NULL); 1516 if (!ret) { 1517 struct seq_file *m = filp->private_data; 1518 1519 m->private = inode; 1520 } 1521 return ret; 1522 } 1523 1524 static const struct file_operations proc_pid_sched_autogroup_operations = { 1525 .open = sched_autogroup_open, 1526 .read = seq_read, 1527 .write = sched_autogroup_write, 1528 .llseek = seq_lseek, 1529 .release = single_release, 1530 }; 1531 1532 #endif /* CONFIG_SCHED_AUTOGROUP */ 1533 1534 static ssize_t comm_write(struct file *file, const char __user *buf, 1535 size_t count, loff_t *offset) 1536 { 1537 struct inode *inode = file_inode(file); 1538 struct task_struct *p; 1539 char buffer[TASK_COMM_LEN]; 1540 const size_t maxlen = sizeof(buffer) - 1; 1541 1542 memset(buffer, 0, sizeof(buffer)); 1543 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count)) 1544 return -EFAULT; 1545 1546 p = get_proc_task(inode); 1547 if (!p) 1548 return -ESRCH; 1549 1550 if (same_thread_group(current, p)) 1551 set_task_comm(p, buffer); 1552 else 1553 count = -EINVAL; 1554 1555 put_task_struct(p); 1556 1557 return count; 1558 } 1559 1560 static int comm_show(struct seq_file *m, void *v) 1561 { 1562 struct inode *inode = m->private; 1563 struct task_struct *p; 1564 1565 p = get_proc_task(inode); 1566 if (!p) 1567 return -ESRCH; 1568 1569 task_lock(p); 1570 seq_printf(m, "%s\n", p->comm); 1571 task_unlock(p); 1572 1573 put_task_struct(p); 1574 1575 return 0; 1576 } 1577 1578 static int comm_open(struct inode *inode, struct file *filp) 1579 { 1580 return single_open(filp, comm_show, inode); 1581 } 1582 1583 static const struct file_operations proc_pid_set_comm_operations = { 1584 .open = comm_open, 1585 .read = seq_read, 1586 .write = comm_write, 1587 .llseek = seq_lseek, 1588 .release = single_release, 1589 }; 1590 1591 static int proc_exe_link(struct dentry *dentry, struct path *exe_path) 1592 { 1593 struct task_struct *task; 1594 struct file *exe_file; 1595 1596 task = get_proc_task(d_inode(dentry)); 1597 if (!task) 1598 return -ENOENT; 1599 exe_file = get_task_exe_file(task); 1600 put_task_struct(task); 1601 if (exe_file) { 1602 *exe_path = exe_file->f_path; 1603 path_get(&exe_file->f_path); 1604 fput(exe_file); 1605 return 0; 1606 } else 1607 return -ENOENT; 1608 } 1609 1610 static const char *proc_pid_get_link(struct dentry *dentry, 1611 struct inode *inode, 1612 struct delayed_call *done) 1613 { 1614 struct path path; 1615 int error = -EACCES; 1616 1617 if (!dentry) 1618 return ERR_PTR(-ECHILD); 1619 1620 /* Are we allowed to snoop on the tasks file descriptors? */ 1621 if (!proc_fd_access_allowed(inode)) 1622 goto out; 1623 1624 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1625 if (error) 1626 goto out; 1627 1628 nd_jump_link(&path); 1629 return NULL; 1630 out: 1631 return ERR_PTR(error); 1632 } 1633 1634 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1635 { 1636 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1637 char *pathname; 1638 int len; 1639 1640 if (!tmp) 1641 return -ENOMEM; 1642 1643 pathname = d_path(path, tmp, PAGE_SIZE); 1644 len = PTR_ERR(pathname); 1645 if (IS_ERR(pathname)) 1646 goto out; 1647 len = tmp + PAGE_SIZE - 1 - pathname; 1648 1649 if (len > buflen) 1650 len = buflen; 1651 if (copy_to_user(buffer, pathname, len)) 1652 len = -EFAULT; 1653 out: 1654 free_page((unsigned long)tmp); 1655 return len; 1656 } 1657 1658 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1659 { 1660 int error = -EACCES; 1661 struct inode *inode = d_inode(dentry); 1662 struct path path; 1663 1664 /* Are we allowed to snoop on the tasks file descriptors? */ 1665 if (!proc_fd_access_allowed(inode)) 1666 goto out; 1667 1668 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1669 if (error) 1670 goto out; 1671 1672 error = do_proc_readlink(&path, buffer, buflen); 1673 path_put(&path); 1674 out: 1675 return error; 1676 } 1677 1678 const struct inode_operations proc_pid_link_inode_operations = { 1679 .readlink = proc_pid_readlink, 1680 .get_link = proc_pid_get_link, 1681 .setattr = proc_setattr, 1682 }; 1683 1684 1685 /* building an inode */ 1686 1687 void task_dump_owner(struct task_struct *task, mode_t mode, 1688 kuid_t *ruid, kgid_t *rgid) 1689 { 1690 /* Depending on the state of dumpable compute who should own a 1691 * proc file for a task. 1692 */ 1693 const struct cred *cred; 1694 kuid_t uid; 1695 kgid_t gid; 1696 1697 /* Default to the tasks effective ownership */ 1698 rcu_read_lock(); 1699 cred = __task_cred(task); 1700 uid = cred->euid; 1701 gid = cred->egid; 1702 rcu_read_unlock(); 1703 1704 /* 1705 * Before the /proc/pid/status file was created the only way to read 1706 * the effective uid of a /process was to stat /proc/pid. Reading 1707 * /proc/pid/status is slow enough that procps and other packages 1708 * kept stating /proc/pid. To keep the rules in /proc simple I have 1709 * made this apply to all per process world readable and executable 1710 * directories. 1711 */ 1712 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) { 1713 struct mm_struct *mm; 1714 task_lock(task); 1715 mm = task->mm; 1716 /* Make non-dumpable tasks owned by some root */ 1717 if (mm) { 1718 if (get_dumpable(mm) != SUID_DUMP_USER) { 1719 struct user_namespace *user_ns = mm->user_ns; 1720 1721 uid = make_kuid(user_ns, 0); 1722 if (!uid_valid(uid)) 1723 uid = GLOBAL_ROOT_UID; 1724 1725 gid = make_kgid(user_ns, 0); 1726 if (!gid_valid(gid)) 1727 gid = GLOBAL_ROOT_GID; 1728 } 1729 } else { 1730 uid = GLOBAL_ROOT_UID; 1731 gid = GLOBAL_ROOT_GID; 1732 } 1733 task_unlock(task); 1734 } 1735 *ruid = uid; 1736 *rgid = gid; 1737 } 1738 1739 struct inode *proc_pid_make_inode(struct super_block * sb, 1740 struct task_struct *task, umode_t mode) 1741 { 1742 struct inode * inode; 1743 struct proc_inode *ei; 1744 1745 /* We need a new inode */ 1746 1747 inode = new_inode(sb); 1748 if (!inode) 1749 goto out; 1750 1751 /* Common stuff */ 1752 ei = PROC_I(inode); 1753 inode->i_mode = mode; 1754 inode->i_ino = get_next_ino(); 1755 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); 1756 inode->i_op = &proc_def_inode_operations; 1757 1758 /* 1759 * grab the reference to task. 1760 */ 1761 ei->pid = get_task_pid(task, PIDTYPE_PID); 1762 if (!ei->pid) 1763 goto out_unlock; 1764 1765 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1766 security_task_to_inode(task, inode); 1767 1768 out: 1769 return inode; 1770 1771 out_unlock: 1772 iput(inode); 1773 return NULL; 1774 } 1775 1776 int pid_getattr(const struct path *path, struct kstat *stat, 1777 u32 request_mask, unsigned int query_flags) 1778 { 1779 struct inode *inode = d_inode(path->dentry); 1780 struct task_struct *task; 1781 struct pid_namespace *pid = path->dentry->d_sb->s_fs_info; 1782 1783 generic_fillattr(inode, stat); 1784 1785 rcu_read_lock(); 1786 stat->uid = GLOBAL_ROOT_UID; 1787 stat->gid = GLOBAL_ROOT_GID; 1788 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1789 if (task) { 1790 if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) { 1791 rcu_read_unlock(); 1792 /* 1793 * This doesn't prevent learning whether PID exists, 1794 * it only makes getattr() consistent with readdir(). 1795 */ 1796 return -ENOENT; 1797 } 1798 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid); 1799 } 1800 rcu_read_unlock(); 1801 return 0; 1802 } 1803 1804 /* dentry stuff */ 1805 1806 /* 1807 * Exceptional case: normally we are not allowed to unhash a busy 1808 * directory. In this case, however, we can do it - no aliasing problems 1809 * due to the way we treat inodes. 1810 * 1811 * Rewrite the inode's ownerships here because the owning task may have 1812 * performed a setuid(), etc. 1813 * 1814 */ 1815 int pid_revalidate(struct dentry *dentry, unsigned int flags) 1816 { 1817 struct inode *inode; 1818 struct task_struct *task; 1819 1820 if (flags & LOOKUP_RCU) 1821 return -ECHILD; 1822 1823 inode = d_inode(dentry); 1824 task = get_proc_task(inode); 1825 1826 if (task) { 1827 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid); 1828 1829 inode->i_mode &= ~(S_ISUID | S_ISGID); 1830 security_task_to_inode(task, inode); 1831 put_task_struct(task); 1832 return 1; 1833 } 1834 return 0; 1835 } 1836 1837 static inline bool proc_inode_is_dead(struct inode *inode) 1838 { 1839 return !proc_pid(inode)->tasks[PIDTYPE_PID].first; 1840 } 1841 1842 int pid_delete_dentry(const struct dentry *dentry) 1843 { 1844 /* Is the task we represent dead? 1845 * If so, then don't put the dentry on the lru list, 1846 * kill it immediately. 1847 */ 1848 return proc_inode_is_dead(d_inode(dentry)); 1849 } 1850 1851 const struct dentry_operations pid_dentry_operations = 1852 { 1853 .d_revalidate = pid_revalidate, 1854 .d_delete = pid_delete_dentry, 1855 }; 1856 1857 /* Lookups */ 1858 1859 /* 1860 * Fill a directory entry. 1861 * 1862 * If possible create the dcache entry and derive our inode number and 1863 * file type from dcache entry. 1864 * 1865 * Since all of the proc inode numbers are dynamically generated, the inode 1866 * numbers do not exist until the inode is cache. This means creating the 1867 * the dcache entry in readdir is necessary to keep the inode numbers 1868 * reported by readdir in sync with the inode numbers reported 1869 * by stat. 1870 */ 1871 bool proc_fill_cache(struct file *file, struct dir_context *ctx, 1872 const char *name, int len, 1873 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1874 { 1875 struct dentry *child, *dir = file->f_path.dentry; 1876 struct qstr qname = QSTR_INIT(name, len); 1877 struct inode *inode; 1878 unsigned type; 1879 ino_t ino; 1880 1881 child = d_hash_and_lookup(dir, &qname); 1882 if (!child) { 1883 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); 1884 child = d_alloc_parallel(dir, &qname, &wq); 1885 if (IS_ERR(child)) 1886 goto end_instantiate; 1887 if (d_in_lookup(child)) { 1888 int err = instantiate(d_inode(dir), child, task, ptr); 1889 d_lookup_done(child); 1890 if (err < 0) { 1891 dput(child); 1892 goto end_instantiate; 1893 } 1894 } 1895 } 1896 inode = d_inode(child); 1897 ino = inode->i_ino; 1898 type = inode->i_mode >> 12; 1899 dput(child); 1900 return dir_emit(ctx, name, len, ino, type); 1901 1902 end_instantiate: 1903 return dir_emit(ctx, name, len, 1, DT_UNKNOWN); 1904 } 1905 1906 /* 1907 * dname_to_vma_addr - maps a dentry name into two unsigned longs 1908 * which represent vma start and end addresses. 1909 */ 1910 static int dname_to_vma_addr(struct dentry *dentry, 1911 unsigned long *start, unsigned long *end) 1912 { 1913 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2) 1914 return -EINVAL; 1915 1916 return 0; 1917 } 1918 1919 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) 1920 { 1921 unsigned long vm_start, vm_end; 1922 bool exact_vma_exists = false; 1923 struct mm_struct *mm = NULL; 1924 struct task_struct *task; 1925 struct inode *inode; 1926 int status = 0; 1927 1928 if (flags & LOOKUP_RCU) 1929 return -ECHILD; 1930 1931 inode = d_inode(dentry); 1932 task = get_proc_task(inode); 1933 if (!task) 1934 goto out_notask; 1935 1936 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); 1937 if (IS_ERR_OR_NULL(mm)) 1938 goto out; 1939 1940 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { 1941 down_read(&mm->mmap_sem); 1942 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); 1943 up_read(&mm->mmap_sem); 1944 } 1945 1946 mmput(mm); 1947 1948 if (exact_vma_exists) { 1949 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1950 1951 security_task_to_inode(task, inode); 1952 status = 1; 1953 } 1954 1955 out: 1956 put_task_struct(task); 1957 1958 out_notask: 1959 return status; 1960 } 1961 1962 static const struct dentry_operations tid_map_files_dentry_operations = { 1963 .d_revalidate = map_files_d_revalidate, 1964 .d_delete = pid_delete_dentry, 1965 }; 1966 1967 static int map_files_get_link(struct dentry *dentry, struct path *path) 1968 { 1969 unsigned long vm_start, vm_end; 1970 struct vm_area_struct *vma; 1971 struct task_struct *task; 1972 struct mm_struct *mm; 1973 int rc; 1974 1975 rc = -ENOENT; 1976 task = get_proc_task(d_inode(dentry)); 1977 if (!task) 1978 goto out; 1979 1980 mm = get_task_mm(task); 1981 put_task_struct(task); 1982 if (!mm) 1983 goto out; 1984 1985 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); 1986 if (rc) 1987 goto out_mmput; 1988 1989 rc = -ENOENT; 1990 down_read(&mm->mmap_sem); 1991 vma = find_exact_vma(mm, vm_start, vm_end); 1992 if (vma && vma->vm_file) { 1993 *path = vma->vm_file->f_path; 1994 path_get(path); 1995 rc = 0; 1996 } 1997 up_read(&mm->mmap_sem); 1998 1999 out_mmput: 2000 mmput(mm); 2001 out: 2002 return rc; 2003 } 2004 2005 struct map_files_info { 2006 fmode_t mode; 2007 unsigned int len; 2008 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */ 2009 }; 2010 2011 /* 2012 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the 2013 * symlinks may be used to bypass permissions on ancestor directories in the 2014 * path to the file in question. 2015 */ 2016 static const char * 2017 proc_map_files_get_link(struct dentry *dentry, 2018 struct inode *inode, 2019 struct delayed_call *done) 2020 { 2021 if (!capable(CAP_SYS_ADMIN)) 2022 return ERR_PTR(-EPERM); 2023 2024 return proc_pid_get_link(dentry, inode, done); 2025 } 2026 2027 /* 2028 * Identical to proc_pid_link_inode_operations except for get_link() 2029 */ 2030 static const struct inode_operations proc_map_files_link_inode_operations = { 2031 .readlink = proc_pid_readlink, 2032 .get_link = proc_map_files_get_link, 2033 .setattr = proc_setattr, 2034 }; 2035 2036 static int 2037 proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, 2038 struct task_struct *task, const void *ptr) 2039 { 2040 fmode_t mode = (fmode_t)(unsigned long)ptr; 2041 struct proc_inode *ei; 2042 struct inode *inode; 2043 2044 inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK | 2045 ((mode & FMODE_READ ) ? S_IRUSR : 0) | 2046 ((mode & FMODE_WRITE) ? S_IWUSR : 0)); 2047 if (!inode) 2048 return -ENOENT; 2049 2050 ei = PROC_I(inode); 2051 ei->op.proc_get_link = map_files_get_link; 2052 2053 inode->i_op = &proc_map_files_link_inode_operations; 2054 inode->i_size = 64; 2055 2056 d_set_d_op(dentry, &tid_map_files_dentry_operations); 2057 d_add(dentry, inode); 2058 2059 return 0; 2060 } 2061 2062 static struct dentry *proc_map_files_lookup(struct inode *dir, 2063 struct dentry *dentry, unsigned int flags) 2064 { 2065 unsigned long vm_start, vm_end; 2066 struct vm_area_struct *vma; 2067 struct task_struct *task; 2068 int result; 2069 struct mm_struct *mm; 2070 2071 result = -ENOENT; 2072 task = get_proc_task(dir); 2073 if (!task) 2074 goto out; 2075 2076 result = -EACCES; 2077 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2078 goto out_put_task; 2079 2080 result = -ENOENT; 2081 if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) 2082 goto out_put_task; 2083 2084 mm = get_task_mm(task); 2085 if (!mm) 2086 goto out_put_task; 2087 2088 down_read(&mm->mmap_sem); 2089 vma = find_exact_vma(mm, vm_start, vm_end); 2090 if (!vma) 2091 goto out_no_vma; 2092 2093 if (vma->vm_file) 2094 result = proc_map_files_instantiate(dir, dentry, task, 2095 (void *)(unsigned long)vma->vm_file->f_mode); 2096 2097 out_no_vma: 2098 up_read(&mm->mmap_sem); 2099 mmput(mm); 2100 out_put_task: 2101 put_task_struct(task); 2102 out: 2103 return ERR_PTR(result); 2104 } 2105 2106 static const struct inode_operations proc_map_files_inode_operations = { 2107 .lookup = proc_map_files_lookup, 2108 .permission = proc_fd_permission, 2109 .setattr = proc_setattr, 2110 }; 2111 2112 static int 2113 proc_map_files_readdir(struct file *file, struct dir_context *ctx) 2114 { 2115 struct vm_area_struct *vma; 2116 struct task_struct *task; 2117 struct mm_struct *mm; 2118 unsigned long nr_files, pos, i; 2119 struct flex_array *fa = NULL; 2120 struct map_files_info info; 2121 struct map_files_info *p; 2122 int ret; 2123 2124 ret = -ENOENT; 2125 task = get_proc_task(file_inode(file)); 2126 if (!task) 2127 goto out; 2128 2129 ret = -EACCES; 2130 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2131 goto out_put_task; 2132 2133 ret = 0; 2134 if (!dir_emit_dots(file, ctx)) 2135 goto out_put_task; 2136 2137 mm = get_task_mm(task); 2138 if (!mm) 2139 goto out_put_task; 2140 down_read(&mm->mmap_sem); 2141 2142 nr_files = 0; 2143 2144 /* 2145 * We need two passes here: 2146 * 2147 * 1) Collect vmas of mapped files with mmap_sem taken 2148 * 2) Release mmap_sem and instantiate entries 2149 * 2150 * otherwise we get lockdep complained, since filldir() 2151 * routine might require mmap_sem taken in might_fault(). 2152 */ 2153 2154 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { 2155 if (vma->vm_file && ++pos > ctx->pos) 2156 nr_files++; 2157 } 2158 2159 if (nr_files) { 2160 fa = flex_array_alloc(sizeof(info), nr_files, 2161 GFP_KERNEL); 2162 if (!fa || flex_array_prealloc(fa, 0, nr_files, 2163 GFP_KERNEL)) { 2164 ret = -ENOMEM; 2165 if (fa) 2166 flex_array_free(fa); 2167 up_read(&mm->mmap_sem); 2168 mmput(mm); 2169 goto out_put_task; 2170 } 2171 for (i = 0, vma = mm->mmap, pos = 2; vma; 2172 vma = vma->vm_next) { 2173 if (!vma->vm_file) 2174 continue; 2175 if (++pos <= ctx->pos) 2176 continue; 2177 2178 info.mode = vma->vm_file->f_mode; 2179 info.len = snprintf(info.name, 2180 sizeof(info.name), "%lx-%lx", 2181 vma->vm_start, vma->vm_end); 2182 if (flex_array_put(fa, i++, &info, GFP_KERNEL)) 2183 BUG(); 2184 } 2185 } 2186 up_read(&mm->mmap_sem); 2187 2188 for (i = 0; i < nr_files; i++) { 2189 p = flex_array_get(fa, i); 2190 if (!proc_fill_cache(file, ctx, 2191 p->name, p->len, 2192 proc_map_files_instantiate, 2193 task, 2194 (void *)(unsigned long)p->mode)) 2195 break; 2196 ctx->pos++; 2197 } 2198 if (fa) 2199 flex_array_free(fa); 2200 mmput(mm); 2201 2202 out_put_task: 2203 put_task_struct(task); 2204 out: 2205 return ret; 2206 } 2207 2208 static const struct file_operations proc_map_files_operations = { 2209 .read = generic_read_dir, 2210 .iterate_shared = proc_map_files_readdir, 2211 .llseek = generic_file_llseek, 2212 }; 2213 2214 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 2215 struct timers_private { 2216 struct pid *pid; 2217 struct task_struct *task; 2218 struct sighand_struct *sighand; 2219 struct pid_namespace *ns; 2220 unsigned long flags; 2221 }; 2222 2223 static void *timers_start(struct seq_file *m, loff_t *pos) 2224 { 2225 struct timers_private *tp = m->private; 2226 2227 tp->task = get_pid_task(tp->pid, PIDTYPE_PID); 2228 if (!tp->task) 2229 return ERR_PTR(-ESRCH); 2230 2231 tp->sighand = lock_task_sighand(tp->task, &tp->flags); 2232 if (!tp->sighand) 2233 return ERR_PTR(-ESRCH); 2234 2235 return seq_list_start(&tp->task->signal->posix_timers, *pos); 2236 } 2237 2238 static void *timers_next(struct seq_file *m, void *v, loff_t *pos) 2239 { 2240 struct timers_private *tp = m->private; 2241 return seq_list_next(v, &tp->task->signal->posix_timers, pos); 2242 } 2243 2244 static void timers_stop(struct seq_file *m, void *v) 2245 { 2246 struct timers_private *tp = m->private; 2247 2248 if (tp->sighand) { 2249 unlock_task_sighand(tp->task, &tp->flags); 2250 tp->sighand = NULL; 2251 } 2252 2253 if (tp->task) { 2254 put_task_struct(tp->task); 2255 tp->task = NULL; 2256 } 2257 } 2258 2259 static int show_timer(struct seq_file *m, void *v) 2260 { 2261 struct k_itimer *timer; 2262 struct timers_private *tp = m->private; 2263 int notify; 2264 static const char * const nstr[] = { 2265 [SIGEV_SIGNAL] = "signal", 2266 [SIGEV_NONE] = "none", 2267 [SIGEV_THREAD] = "thread", 2268 }; 2269 2270 timer = list_entry((struct list_head *)v, struct k_itimer, list); 2271 notify = timer->it_sigev_notify; 2272 2273 seq_printf(m, "ID: %d\n", timer->it_id); 2274 seq_printf(m, "signal: %d/%p\n", 2275 timer->sigq->info.si_signo, 2276 timer->sigq->info.si_value.sival_ptr); 2277 seq_printf(m, "notify: %s/%s.%d\n", 2278 nstr[notify & ~SIGEV_THREAD_ID], 2279 (notify & SIGEV_THREAD_ID) ? "tid" : "pid", 2280 pid_nr_ns(timer->it_pid, tp->ns)); 2281 seq_printf(m, "ClockID: %d\n", timer->it_clock); 2282 2283 return 0; 2284 } 2285 2286 static const struct seq_operations proc_timers_seq_ops = { 2287 .start = timers_start, 2288 .next = timers_next, 2289 .stop = timers_stop, 2290 .show = show_timer, 2291 }; 2292 2293 static int proc_timers_open(struct inode *inode, struct file *file) 2294 { 2295 struct timers_private *tp; 2296 2297 tp = __seq_open_private(file, &proc_timers_seq_ops, 2298 sizeof(struct timers_private)); 2299 if (!tp) 2300 return -ENOMEM; 2301 2302 tp->pid = proc_pid(inode); 2303 tp->ns = inode->i_sb->s_fs_info; 2304 return 0; 2305 } 2306 2307 static const struct file_operations proc_timers_operations = { 2308 .open = proc_timers_open, 2309 .read = seq_read, 2310 .llseek = seq_lseek, 2311 .release = seq_release_private, 2312 }; 2313 #endif 2314 2315 static ssize_t timerslack_ns_write(struct file *file, const char __user *buf, 2316 size_t count, loff_t *offset) 2317 { 2318 struct inode *inode = file_inode(file); 2319 struct task_struct *p; 2320 u64 slack_ns; 2321 int err; 2322 2323 err = kstrtoull_from_user(buf, count, 10, &slack_ns); 2324 if (err < 0) 2325 return err; 2326 2327 p = get_proc_task(inode); 2328 if (!p) 2329 return -ESRCH; 2330 2331 if (p != current) { 2332 if (!capable(CAP_SYS_NICE)) { 2333 count = -EPERM; 2334 goto out; 2335 } 2336 2337 err = security_task_setscheduler(p); 2338 if (err) { 2339 count = err; 2340 goto out; 2341 } 2342 } 2343 2344 task_lock(p); 2345 if (slack_ns == 0) 2346 p->timer_slack_ns = p->default_timer_slack_ns; 2347 else 2348 p->timer_slack_ns = slack_ns; 2349 task_unlock(p); 2350 2351 out: 2352 put_task_struct(p); 2353 2354 return count; 2355 } 2356 2357 static int timerslack_ns_show(struct seq_file *m, void *v) 2358 { 2359 struct inode *inode = m->private; 2360 struct task_struct *p; 2361 int err = 0; 2362 2363 p = get_proc_task(inode); 2364 if (!p) 2365 return -ESRCH; 2366 2367 if (p != current) { 2368 2369 if (!capable(CAP_SYS_NICE)) { 2370 err = -EPERM; 2371 goto out; 2372 } 2373 err = security_task_getscheduler(p); 2374 if (err) 2375 goto out; 2376 } 2377 2378 task_lock(p); 2379 seq_printf(m, "%llu\n", p->timer_slack_ns); 2380 task_unlock(p); 2381 2382 out: 2383 put_task_struct(p); 2384 2385 return err; 2386 } 2387 2388 static int timerslack_ns_open(struct inode *inode, struct file *filp) 2389 { 2390 return single_open(filp, timerslack_ns_show, inode); 2391 } 2392 2393 static const struct file_operations proc_pid_set_timerslack_ns_operations = { 2394 .open = timerslack_ns_open, 2395 .read = seq_read, 2396 .write = timerslack_ns_write, 2397 .llseek = seq_lseek, 2398 .release = single_release, 2399 }; 2400 2401 static int proc_pident_instantiate(struct inode *dir, 2402 struct dentry *dentry, struct task_struct *task, const void *ptr) 2403 { 2404 const struct pid_entry *p = ptr; 2405 struct inode *inode; 2406 struct proc_inode *ei; 2407 2408 inode = proc_pid_make_inode(dir->i_sb, task, p->mode); 2409 if (!inode) 2410 goto out; 2411 2412 ei = PROC_I(inode); 2413 if (S_ISDIR(inode->i_mode)) 2414 set_nlink(inode, 2); /* Use getattr to fix if necessary */ 2415 if (p->iop) 2416 inode->i_op = p->iop; 2417 if (p->fop) 2418 inode->i_fop = p->fop; 2419 ei->op = p->op; 2420 d_set_d_op(dentry, &pid_dentry_operations); 2421 d_add(dentry, inode); 2422 /* Close the race of the process dying before we return the dentry */ 2423 if (pid_revalidate(dentry, 0)) 2424 return 0; 2425 out: 2426 return -ENOENT; 2427 } 2428 2429 static struct dentry *proc_pident_lookup(struct inode *dir, 2430 struct dentry *dentry, 2431 const struct pid_entry *ents, 2432 unsigned int nents) 2433 { 2434 int error; 2435 struct task_struct *task = get_proc_task(dir); 2436 const struct pid_entry *p, *last; 2437 2438 error = -ENOENT; 2439 2440 if (!task) 2441 goto out_no_task; 2442 2443 /* 2444 * Yes, it does not scale. And it should not. Don't add 2445 * new entries into /proc/<tgid>/ without very good reasons. 2446 */ 2447 last = &ents[nents]; 2448 for (p = ents; p < last; p++) { 2449 if (p->len != dentry->d_name.len) 2450 continue; 2451 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2452 break; 2453 } 2454 if (p >= last) 2455 goto out; 2456 2457 error = proc_pident_instantiate(dir, dentry, task, p); 2458 out: 2459 put_task_struct(task); 2460 out_no_task: 2461 return ERR_PTR(error); 2462 } 2463 2464 static int proc_pident_readdir(struct file *file, struct dir_context *ctx, 2465 const struct pid_entry *ents, unsigned int nents) 2466 { 2467 struct task_struct *task = get_proc_task(file_inode(file)); 2468 const struct pid_entry *p; 2469 2470 if (!task) 2471 return -ENOENT; 2472 2473 if (!dir_emit_dots(file, ctx)) 2474 goto out; 2475 2476 if (ctx->pos >= nents + 2) 2477 goto out; 2478 2479 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) { 2480 if (!proc_fill_cache(file, ctx, p->name, p->len, 2481 proc_pident_instantiate, task, p)) 2482 break; 2483 ctx->pos++; 2484 } 2485 out: 2486 put_task_struct(task); 2487 return 0; 2488 } 2489 2490 #ifdef CONFIG_SECURITY 2491 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2492 size_t count, loff_t *ppos) 2493 { 2494 struct inode * inode = file_inode(file); 2495 char *p = NULL; 2496 ssize_t length; 2497 struct task_struct *task = get_proc_task(inode); 2498 2499 if (!task) 2500 return -ESRCH; 2501 2502 length = security_getprocattr(task, 2503 (char*)file->f_path.dentry->d_name.name, 2504 &p); 2505 put_task_struct(task); 2506 if (length > 0) 2507 length = simple_read_from_buffer(buf, count, ppos, p, length); 2508 kfree(p); 2509 return length; 2510 } 2511 2512 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2513 size_t count, loff_t *ppos) 2514 { 2515 struct inode * inode = file_inode(file); 2516 void *page; 2517 ssize_t length; 2518 struct task_struct *task = get_proc_task(inode); 2519 2520 length = -ESRCH; 2521 if (!task) 2522 goto out_no_task; 2523 2524 /* A task may only write its own attributes. */ 2525 length = -EACCES; 2526 if (current != task) 2527 goto out; 2528 2529 if (count > PAGE_SIZE) 2530 count = PAGE_SIZE; 2531 2532 /* No partial writes. */ 2533 length = -EINVAL; 2534 if (*ppos != 0) 2535 goto out; 2536 2537 page = memdup_user(buf, count); 2538 if (IS_ERR(page)) { 2539 length = PTR_ERR(page); 2540 goto out; 2541 } 2542 2543 /* Guard against adverse ptrace interaction */ 2544 length = mutex_lock_interruptible(¤t->signal->cred_guard_mutex); 2545 if (length < 0) 2546 goto out_free; 2547 2548 length = security_setprocattr(file->f_path.dentry->d_name.name, 2549 page, count); 2550 mutex_unlock(¤t->signal->cred_guard_mutex); 2551 out_free: 2552 kfree(page); 2553 out: 2554 put_task_struct(task); 2555 out_no_task: 2556 return length; 2557 } 2558 2559 static const struct file_operations proc_pid_attr_operations = { 2560 .read = proc_pid_attr_read, 2561 .write = proc_pid_attr_write, 2562 .llseek = generic_file_llseek, 2563 }; 2564 2565 static const struct pid_entry attr_dir_stuff[] = { 2566 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2567 REG("prev", S_IRUGO, proc_pid_attr_operations), 2568 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2569 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2570 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2571 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2572 }; 2573 2574 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) 2575 { 2576 return proc_pident_readdir(file, ctx, 2577 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2578 } 2579 2580 static const struct file_operations proc_attr_dir_operations = { 2581 .read = generic_read_dir, 2582 .iterate_shared = proc_attr_dir_readdir, 2583 .llseek = generic_file_llseek, 2584 }; 2585 2586 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2587 struct dentry *dentry, unsigned int flags) 2588 { 2589 return proc_pident_lookup(dir, dentry, 2590 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2591 } 2592 2593 static const struct inode_operations proc_attr_dir_inode_operations = { 2594 .lookup = proc_attr_dir_lookup, 2595 .getattr = pid_getattr, 2596 .setattr = proc_setattr, 2597 }; 2598 2599 #endif 2600 2601 #ifdef CONFIG_ELF_CORE 2602 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2603 size_t count, loff_t *ppos) 2604 { 2605 struct task_struct *task = get_proc_task(file_inode(file)); 2606 struct mm_struct *mm; 2607 char buffer[PROC_NUMBUF]; 2608 size_t len; 2609 int ret; 2610 2611 if (!task) 2612 return -ESRCH; 2613 2614 ret = 0; 2615 mm = get_task_mm(task); 2616 if (mm) { 2617 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2618 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2619 MMF_DUMP_FILTER_SHIFT)); 2620 mmput(mm); 2621 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2622 } 2623 2624 put_task_struct(task); 2625 2626 return ret; 2627 } 2628 2629 static ssize_t proc_coredump_filter_write(struct file *file, 2630 const char __user *buf, 2631 size_t count, 2632 loff_t *ppos) 2633 { 2634 struct task_struct *task; 2635 struct mm_struct *mm; 2636 unsigned int val; 2637 int ret; 2638 int i; 2639 unsigned long mask; 2640 2641 ret = kstrtouint_from_user(buf, count, 0, &val); 2642 if (ret < 0) 2643 return ret; 2644 2645 ret = -ESRCH; 2646 task = get_proc_task(file_inode(file)); 2647 if (!task) 2648 goto out_no_task; 2649 2650 mm = get_task_mm(task); 2651 if (!mm) 2652 goto out_no_mm; 2653 ret = 0; 2654 2655 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2656 if (val & mask) 2657 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2658 else 2659 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2660 } 2661 2662 mmput(mm); 2663 out_no_mm: 2664 put_task_struct(task); 2665 out_no_task: 2666 if (ret < 0) 2667 return ret; 2668 return count; 2669 } 2670 2671 static const struct file_operations proc_coredump_filter_operations = { 2672 .read = proc_coredump_filter_read, 2673 .write = proc_coredump_filter_write, 2674 .llseek = generic_file_llseek, 2675 }; 2676 #endif 2677 2678 #ifdef CONFIG_TASK_IO_ACCOUNTING 2679 static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) 2680 { 2681 struct task_io_accounting acct = task->ioac; 2682 unsigned long flags; 2683 int result; 2684 2685 result = mutex_lock_killable(&task->signal->cred_guard_mutex); 2686 if (result) 2687 return result; 2688 2689 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { 2690 result = -EACCES; 2691 goto out_unlock; 2692 } 2693 2694 if (whole && lock_task_sighand(task, &flags)) { 2695 struct task_struct *t = task; 2696 2697 task_io_accounting_add(&acct, &task->signal->ioac); 2698 while_each_thread(task, t) 2699 task_io_accounting_add(&acct, &t->ioac); 2700 2701 unlock_task_sighand(task, &flags); 2702 } 2703 seq_printf(m, 2704 "rchar: %llu\n" 2705 "wchar: %llu\n" 2706 "syscr: %llu\n" 2707 "syscw: %llu\n" 2708 "read_bytes: %llu\n" 2709 "write_bytes: %llu\n" 2710 "cancelled_write_bytes: %llu\n", 2711 (unsigned long long)acct.rchar, 2712 (unsigned long long)acct.wchar, 2713 (unsigned long long)acct.syscr, 2714 (unsigned long long)acct.syscw, 2715 (unsigned long long)acct.read_bytes, 2716 (unsigned long long)acct.write_bytes, 2717 (unsigned long long)acct.cancelled_write_bytes); 2718 result = 0; 2719 2720 out_unlock: 2721 mutex_unlock(&task->signal->cred_guard_mutex); 2722 return result; 2723 } 2724 2725 static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2726 struct pid *pid, struct task_struct *task) 2727 { 2728 return do_io_accounting(task, m, 0); 2729 } 2730 2731 static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2732 struct pid *pid, struct task_struct *task) 2733 { 2734 return do_io_accounting(task, m, 1); 2735 } 2736 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2737 2738 #ifdef CONFIG_USER_NS 2739 static int proc_id_map_open(struct inode *inode, struct file *file, 2740 const struct seq_operations *seq_ops) 2741 { 2742 struct user_namespace *ns = NULL; 2743 struct task_struct *task; 2744 struct seq_file *seq; 2745 int ret = -EINVAL; 2746 2747 task = get_proc_task(inode); 2748 if (task) { 2749 rcu_read_lock(); 2750 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2751 rcu_read_unlock(); 2752 put_task_struct(task); 2753 } 2754 if (!ns) 2755 goto err; 2756 2757 ret = seq_open(file, seq_ops); 2758 if (ret) 2759 goto err_put_ns; 2760 2761 seq = file->private_data; 2762 seq->private = ns; 2763 2764 return 0; 2765 err_put_ns: 2766 put_user_ns(ns); 2767 err: 2768 return ret; 2769 } 2770 2771 static int proc_id_map_release(struct inode *inode, struct file *file) 2772 { 2773 struct seq_file *seq = file->private_data; 2774 struct user_namespace *ns = seq->private; 2775 put_user_ns(ns); 2776 return seq_release(inode, file); 2777 } 2778 2779 static int proc_uid_map_open(struct inode *inode, struct file *file) 2780 { 2781 return proc_id_map_open(inode, file, &proc_uid_seq_operations); 2782 } 2783 2784 static int proc_gid_map_open(struct inode *inode, struct file *file) 2785 { 2786 return proc_id_map_open(inode, file, &proc_gid_seq_operations); 2787 } 2788 2789 static int proc_projid_map_open(struct inode *inode, struct file *file) 2790 { 2791 return proc_id_map_open(inode, file, &proc_projid_seq_operations); 2792 } 2793 2794 static const struct file_operations proc_uid_map_operations = { 2795 .open = proc_uid_map_open, 2796 .write = proc_uid_map_write, 2797 .read = seq_read, 2798 .llseek = seq_lseek, 2799 .release = proc_id_map_release, 2800 }; 2801 2802 static const struct file_operations proc_gid_map_operations = { 2803 .open = proc_gid_map_open, 2804 .write = proc_gid_map_write, 2805 .read = seq_read, 2806 .llseek = seq_lseek, 2807 .release = proc_id_map_release, 2808 }; 2809 2810 static const struct file_operations proc_projid_map_operations = { 2811 .open = proc_projid_map_open, 2812 .write = proc_projid_map_write, 2813 .read = seq_read, 2814 .llseek = seq_lseek, 2815 .release = proc_id_map_release, 2816 }; 2817 2818 static int proc_setgroups_open(struct inode *inode, struct file *file) 2819 { 2820 struct user_namespace *ns = NULL; 2821 struct task_struct *task; 2822 int ret; 2823 2824 ret = -ESRCH; 2825 task = get_proc_task(inode); 2826 if (task) { 2827 rcu_read_lock(); 2828 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2829 rcu_read_unlock(); 2830 put_task_struct(task); 2831 } 2832 if (!ns) 2833 goto err; 2834 2835 if (file->f_mode & FMODE_WRITE) { 2836 ret = -EACCES; 2837 if (!ns_capable(ns, CAP_SYS_ADMIN)) 2838 goto err_put_ns; 2839 } 2840 2841 ret = single_open(file, &proc_setgroups_show, ns); 2842 if (ret) 2843 goto err_put_ns; 2844 2845 return 0; 2846 err_put_ns: 2847 put_user_ns(ns); 2848 err: 2849 return ret; 2850 } 2851 2852 static int proc_setgroups_release(struct inode *inode, struct file *file) 2853 { 2854 struct seq_file *seq = file->private_data; 2855 struct user_namespace *ns = seq->private; 2856 int ret = single_release(inode, file); 2857 put_user_ns(ns); 2858 return ret; 2859 } 2860 2861 static const struct file_operations proc_setgroups_operations = { 2862 .open = proc_setgroups_open, 2863 .write = proc_setgroups_write, 2864 .read = seq_read, 2865 .llseek = seq_lseek, 2866 .release = proc_setgroups_release, 2867 }; 2868 #endif /* CONFIG_USER_NS */ 2869 2870 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2871 struct pid *pid, struct task_struct *task) 2872 { 2873 int err = lock_trace(task); 2874 if (!err) { 2875 seq_printf(m, "%08x\n", task->personality); 2876 unlock_trace(task); 2877 } 2878 return err; 2879 } 2880 2881 #ifdef CONFIG_LIVEPATCH 2882 static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns, 2883 struct pid *pid, struct task_struct *task) 2884 { 2885 seq_printf(m, "%d\n", task->patch_state); 2886 return 0; 2887 } 2888 #endif /* CONFIG_LIVEPATCH */ 2889 2890 /* 2891 * Thread groups 2892 */ 2893 static const struct file_operations proc_task_operations; 2894 static const struct inode_operations proc_task_inode_operations; 2895 2896 static const struct pid_entry tgid_base_stuff[] = { 2897 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2898 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2899 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), 2900 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2901 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2902 #ifdef CONFIG_NET 2903 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2904 #endif 2905 REG("environ", S_IRUSR, proc_environ_operations), 2906 REG("auxv", S_IRUSR, proc_auxv_operations), 2907 ONE("status", S_IRUGO, proc_pid_status), 2908 ONE("personality", S_IRUSR, proc_pid_personality), 2909 ONE("limits", S_IRUGO, proc_pid_limits), 2910 #ifdef CONFIG_SCHED_DEBUG 2911 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2912 #endif 2913 #ifdef CONFIG_SCHED_AUTOGROUP 2914 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), 2915 #endif 2916 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2917 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2918 ONE("syscall", S_IRUSR, proc_pid_syscall), 2919 #endif 2920 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 2921 ONE("stat", S_IRUGO, proc_tgid_stat), 2922 ONE("statm", S_IRUGO, proc_pid_statm), 2923 REG("maps", S_IRUGO, proc_pid_maps_operations), 2924 #ifdef CONFIG_NUMA 2925 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 2926 #endif 2927 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2928 LNK("cwd", proc_cwd_link), 2929 LNK("root", proc_root_link), 2930 LNK("exe", proc_exe_link), 2931 REG("mounts", S_IRUGO, proc_mounts_operations), 2932 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2933 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2934 #ifdef CONFIG_PROC_PAGE_MONITOR 2935 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2936 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 2937 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2938 #endif 2939 #ifdef CONFIG_SECURITY 2940 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2941 #endif 2942 #ifdef CONFIG_KALLSYMS 2943 ONE("wchan", S_IRUGO, proc_pid_wchan), 2944 #endif 2945 #ifdef CONFIG_STACKTRACE 2946 ONE("stack", S_IRUSR, proc_pid_stack), 2947 #endif 2948 #ifdef CONFIG_SCHED_INFO 2949 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 2950 #endif 2951 #ifdef CONFIG_LATENCYTOP 2952 REG("latency", S_IRUGO, proc_lstats_operations), 2953 #endif 2954 #ifdef CONFIG_PROC_PID_CPUSET 2955 ONE("cpuset", S_IRUGO, proc_cpuset_show), 2956 #endif 2957 #ifdef CONFIG_CGROUPS 2958 ONE("cgroup", S_IRUGO, proc_cgroup_show), 2959 #endif 2960 ONE("oom_score", S_IRUGO, proc_oom_score), 2961 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 2962 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2963 #ifdef CONFIG_AUDITSYSCALL 2964 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2965 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2966 #endif 2967 #ifdef CONFIG_FAULT_INJECTION 2968 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2969 #endif 2970 #ifdef CONFIG_ELF_CORE 2971 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2972 #endif 2973 #ifdef CONFIG_TASK_IO_ACCOUNTING 2974 ONE("io", S_IRUSR, proc_tgid_io_accounting), 2975 #endif 2976 #ifdef CONFIG_HARDWALL 2977 ONE("hardwall", S_IRUGO, proc_pid_hardwall), 2978 #endif 2979 #ifdef CONFIG_USER_NS 2980 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2981 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2982 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 2983 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 2984 #endif 2985 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 2986 REG("timers", S_IRUGO, proc_timers_operations), 2987 #endif 2988 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations), 2989 #ifdef CONFIG_LIVEPATCH 2990 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 2991 #endif 2992 }; 2993 2994 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) 2995 { 2996 return proc_pident_readdir(file, ctx, 2997 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2998 } 2999 3000 static const struct file_operations proc_tgid_base_operations = { 3001 .read = generic_read_dir, 3002 .iterate_shared = proc_tgid_base_readdir, 3003 .llseek = generic_file_llseek, 3004 }; 3005 3006 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3007 { 3008 return proc_pident_lookup(dir, dentry, 3009 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3010 } 3011 3012 static const struct inode_operations proc_tgid_base_inode_operations = { 3013 .lookup = proc_tgid_base_lookup, 3014 .getattr = pid_getattr, 3015 .setattr = proc_setattr, 3016 .permission = proc_pid_permission, 3017 }; 3018 3019 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 3020 { 3021 struct dentry *dentry, *leader, *dir; 3022 char buf[PROC_NUMBUF]; 3023 struct qstr name; 3024 3025 name.name = buf; 3026 name.len = snprintf(buf, sizeof(buf), "%d", pid); 3027 /* no ->d_hash() rejects on procfs */ 3028 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 3029 if (dentry) { 3030 d_invalidate(dentry); 3031 dput(dentry); 3032 } 3033 3034 if (pid == tgid) 3035 return; 3036 3037 name.name = buf; 3038 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 3039 leader = d_hash_and_lookup(mnt->mnt_root, &name); 3040 if (!leader) 3041 goto out; 3042 3043 name.name = "task"; 3044 name.len = strlen(name.name); 3045 dir = d_hash_and_lookup(leader, &name); 3046 if (!dir) 3047 goto out_put_leader; 3048 3049 name.name = buf; 3050 name.len = snprintf(buf, sizeof(buf), "%d", pid); 3051 dentry = d_hash_and_lookup(dir, &name); 3052 if (dentry) { 3053 d_invalidate(dentry); 3054 dput(dentry); 3055 } 3056 3057 dput(dir); 3058 out_put_leader: 3059 dput(leader); 3060 out: 3061 return; 3062 } 3063 3064 /** 3065 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 3066 * @task: task that should be flushed. 3067 * 3068 * When flushing dentries from proc, one needs to flush them from global 3069 * proc (proc_mnt) and from all the namespaces' procs this task was seen 3070 * in. This call is supposed to do all of this job. 3071 * 3072 * Looks in the dcache for 3073 * /proc/@pid 3074 * /proc/@tgid/task/@pid 3075 * if either directory is present flushes it and all of it'ts children 3076 * from the dcache. 3077 * 3078 * It is safe and reasonable to cache /proc entries for a task until 3079 * that task exits. After that they just clog up the dcache with 3080 * useless entries, possibly causing useful dcache entries to be 3081 * flushed instead. This routine is proved to flush those useless 3082 * dcache entries at process exit time. 3083 * 3084 * NOTE: This routine is just an optimization so it does not guarantee 3085 * that no dcache entries will exist at process exit time it 3086 * just makes it very unlikely that any will persist. 3087 */ 3088 3089 void proc_flush_task(struct task_struct *task) 3090 { 3091 int i; 3092 struct pid *pid, *tgid; 3093 struct upid *upid; 3094 3095 pid = task_pid(task); 3096 tgid = task_tgid(task); 3097 3098 for (i = 0; i <= pid->level; i++) { 3099 upid = &pid->numbers[i]; 3100 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 3101 tgid->numbers[i].nr); 3102 } 3103 } 3104 3105 static int proc_pid_instantiate(struct inode *dir, 3106 struct dentry * dentry, 3107 struct task_struct *task, const void *ptr) 3108 { 3109 struct inode *inode; 3110 3111 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); 3112 if (!inode) 3113 goto out; 3114 3115 inode->i_op = &proc_tgid_base_inode_operations; 3116 inode->i_fop = &proc_tgid_base_operations; 3117 inode->i_flags|=S_IMMUTABLE; 3118 3119 set_nlink(inode, nlink_tgid); 3120 3121 d_set_d_op(dentry, &pid_dentry_operations); 3122 3123 d_add(dentry, inode); 3124 /* Close the race of the process dying before we return the dentry */ 3125 if (pid_revalidate(dentry, 0)) 3126 return 0; 3127 out: 3128 return -ENOENT; 3129 } 3130 3131 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3132 { 3133 int result = -ENOENT; 3134 struct task_struct *task; 3135 unsigned tgid; 3136 struct pid_namespace *ns; 3137 3138 tgid = name_to_int(&dentry->d_name); 3139 if (tgid == ~0U) 3140 goto out; 3141 3142 ns = dentry->d_sb->s_fs_info; 3143 rcu_read_lock(); 3144 task = find_task_by_pid_ns(tgid, ns); 3145 if (task) 3146 get_task_struct(task); 3147 rcu_read_unlock(); 3148 if (!task) 3149 goto out; 3150 3151 result = proc_pid_instantiate(dir, dentry, task, NULL); 3152 put_task_struct(task); 3153 out: 3154 return ERR_PTR(result); 3155 } 3156 3157 /* 3158 * Find the first task with tgid >= tgid 3159 * 3160 */ 3161 struct tgid_iter { 3162 unsigned int tgid; 3163 struct task_struct *task; 3164 }; 3165 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 3166 { 3167 struct pid *pid; 3168 3169 if (iter.task) 3170 put_task_struct(iter.task); 3171 rcu_read_lock(); 3172 retry: 3173 iter.task = NULL; 3174 pid = find_ge_pid(iter.tgid, ns); 3175 if (pid) { 3176 iter.tgid = pid_nr_ns(pid, ns); 3177 iter.task = pid_task(pid, PIDTYPE_PID); 3178 /* What we to know is if the pid we have find is the 3179 * pid of a thread_group_leader. Testing for task 3180 * being a thread_group_leader is the obvious thing 3181 * todo but there is a window when it fails, due to 3182 * the pid transfer logic in de_thread. 3183 * 3184 * So we perform the straight forward test of seeing 3185 * if the pid we have found is the pid of a thread 3186 * group leader, and don't worry if the task we have 3187 * found doesn't happen to be a thread group leader. 3188 * As we don't care in the case of readdir. 3189 */ 3190 if (!iter.task || !has_group_leader_pid(iter.task)) { 3191 iter.tgid += 1; 3192 goto retry; 3193 } 3194 get_task_struct(iter.task); 3195 } 3196 rcu_read_unlock(); 3197 return iter; 3198 } 3199 3200 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) 3201 3202 /* for the /proc/ directory itself, after non-process stuff has been done */ 3203 int proc_pid_readdir(struct file *file, struct dir_context *ctx) 3204 { 3205 struct tgid_iter iter; 3206 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info; 3207 loff_t pos = ctx->pos; 3208 3209 if (pos >= PID_MAX_LIMIT + TGID_OFFSET) 3210 return 0; 3211 3212 if (pos == TGID_OFFSET - 2) { 3213 struct inode *inode = d_inode(ns->proc_self); 3214 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK)) 3215 return 0; 3216 ctx->pos = pos = pos + 1; 3217 } 3218 if (pos == TGID_OFFSET - 1) { 3219 struct inode *inode = d_inode(ns->proc_thread_self); 3220 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK)) 3221 return 0; 3222 ctx->pos = pos = pos + 1; 3223 } 3224 iter.tgid = pos - TGID_OFFSET; 3225 iter.task = NULL; 3226 for (iter = next_tgid(ns, iter); 3227 iter.task; 3228 iter.tgid += 1, iter = next_tgid(ns, iter)) { 3229 char name[PROC_NUMBUF]; 3230 int len; 3231 3232 cond_resched(); 3233 if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE)) 3234 continue; 3235 3236 len = snprintf(name, sizeof(name), "%d", iter.tgid); 3237 ctx->pos = iter.tgid + TGID_OFFSET; 3238 if (!proc_fill_cache(file, ctx, name, len, 3239 proc_pid_instantiate, iter.task, NULL)) { 3240 put_task_struct(iter.task); 3241 return 0; 3242 } 3243 } 3244 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; 3245 return 0; 3246 } 3247 3248 /* 3249 * proc_tid_comm_permission is a special permission function exclusively 3250 * used for the node /proc/<pid>/task/<tid>/comm. 3251 * It bypasses generic permission checks in the case where a task of the same 3252 * task group attempts to access the node. 3253 * The rationale behind this is that glibc and bionic access this node for 3254 * cross thread naming (pthread_set/getname_np(!self)). However, if 3255 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0, 3256 * which locks out the cross thread naming implementation. 3257 * This function makes sure that the node is always accessible for members of 3258 * same thread group. 3259 */ 3260 static int proc_tid_comm_permission(struct inode *inode, int mask) 3261 { 3262 bool is_same_tgroup; 3263 struct task_struct *task; 3264 3265 task = get_proc_task(inode); 3266 if (!task) 3267 return -ESRCH; 3268 is_same_tgroup = same_thread_group(current, task); 3269 put_task_struct(task); 3270 3271 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) { 3272 /* This file (/proc/<pid>/task/<tid>/comm) can always be 3273 * read or written by the members of the corresponding 3274 * thread group. 3275 */ 3276 return 0; 3277 } 3278 3279 return generic_permission(inode, mask); 3280 } 3281 3282 static const struct inode_operations proc_tid_comm_inode_operations = { 3283 .permission = proc_tid_comm_permission, 3284 }; 3285 3286 /* 3287 * Tasks 3288 */ 3289 static const struct pid_entry tid_base_stuff[] = { 3290 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 3291 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 3292 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 3293 #ifdef CONFIG_NET 3294 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 3295 #endif 3296 REG("environ", S_IRUSR, proc_environ_operations), 3297 REG("auxv", S_IRUSR, proc_auxv_operations), 3298 ONE("status", S_IRUGO, proc_pid_status), 3299 ONE("personality", S_IRUSR, proc_pid_personality), 3300 ONE("limits", S_IRUGO, proc_pid_limits), 3301 #ifdef CONFIG_SCHED_DEBUG 3302 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 3303 #endif 3304 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR, 3305 &proc_tid_comm_inode_operations, 3306 &proc_pid_set_comm_operations, {}), 3307 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 3308 ONE("syscall", S_IRUSR, proc_pid_syscall), 3309 #endif 3310 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 3311 ONE("stat", S_IRUGO, proc_tid_stat), 3312 ONE("statm", S_IRUGO, proc_pid_statm), 3313 REG("maps", S_IRUGO, proc_tid_maps_operations), 3314 #ifdef CONFIG_PROC_CHILDREN 3315 REG("children", S_IRUGO, proc_tid_children_operations), 3316 #endif 3317 #ifdef CONFIG_NUMA 3318 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations), 3319 #endif 3320 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 3321 LNK("cwd", proc_cwd_link), 3322 LNK("root", proc_root_link), 3323 LNK("exe", proc_exe_link), 3324 REG("mounts", S_IRUGO, proc_mounts_operations), 3325 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 3326 #ifdef CONFIG_PROC_PAGE_MONITOR 3327 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 3328 REG("smaps", S_IRUGO, proc_tid_smaps_operations), 3329 REG("pagemap", S_IRUSR, proc_pagemap_operations), 3330 #endif 3331 #ifdef CONFIG_SECURITY 3332 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 3333 #endif 3334 #ifdef CONFIG_KALLSYMS 3335 ONE("wchan", S_IRUGO, proc_pid_wchan), 3336 #endif 3337 #ifdef CONFIG_STACKTRACE 3338 ONE("stack", S_IRUSR, proc_pid_stack), 3339 #endif 3340 #ifdef CONFIG_SCHED_INFO 3341 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 3342 #endif 3343 #ifdef CONFIG_LATENCYTOP 3344 REG("latency", S_IRUGO, proc_lstats_operations), 3345 #endif 3346 #ifdef CONFIG_PROC_PID_CPUSET 3347 ONE("cpuset", S_IRUGO, proc_cpuset_show), 3348 #endif 3349 #ifdef CONFIG_CGROUPS 3350 ONE("cgroup", S_IRUGO, proc_cgroup_show), 3351 #endif 3352 ONE("oom_score", S_IRUGO, proc_oom_score), 3353 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 3354 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 3355 #ifdef CONFIG_AUDITSYSCALL 3356 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 3357 REG("sessionid", S_IRUGO, proc_sessionid_operations), 3358 #endif 3359 #ifdef CONFIG_FAULT_INJECTION 3360 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 3361 /* 3362 * Operations on the file check that the task is current, 3363 * so we create it with 0666 to support testing under unprivileged user. 3364 */ 3365 REG("fail-nth", 0666, proc_fail_nth_operations), 3366 #endif 3367 #ifdef CONFIG_TASK_IO_ACCOUNTING 3368 ONE("io", S_IRUSR, proc_tid_io_accounting), 3369 #endif 3370 #ifdef CONFIG_HARDWALL 3371 ONE("hardwall", S_IRUGO, proc_pid_hardwall), 3372 #endif 3373 #ifdef CONFIG_USER_NS 3374 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 3375 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 3376 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 3377 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 3378 #endif 3379 #ifdef CONFIG_LIVEPATCH 3380 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 3381 #endif 3382 }; 3383 3384 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) 3385 { 3386 return proc_pident_readdir(file, ctx, 3387 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3388 } 3389 3390 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3391 { 3392 return proc_pident_lookup(dir, dentry, 3393 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3394 } 3395 3396 static const struct file_operations proc_tid_base_operations = { 3397 .read = generic_read_dir, 3398 .iterate_shared = proc_tid_base_readdir, 3399 .llseek = generic_file_llseek, 3400 }; 3401 3402 static const struct inode_operations proc_tid_base_inode_operations = { 3403 .lookup = proc_tid_base_lookup, 3404 .getattr = pid_getattr, 3405 .setattr = proc_setattr, 3406 }; 3407 3408 static int proc_task_instantiate(struct inode *dir, 3409 struct dentry *dentry, struct task_struct *task, const void *ptr) 3410 { 3411 struct inode *inode; 3412 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); 3413 3414 if (!inode) 3415 goto out; 3416 inode->i_op = &proc_tid_base_inode_operations; 3417 inode->i_fop = &proc_tid_base_operations; 3418 inode->i_flags|=S_IMMUTABLE; 3419 3420 set_nlink(inode, nlink_tid); 3421 3422 d_set_d_op(dentry, &pid_dentry_operations); 3423 3424 d_add(dentry, inode); 3425 /* Close the race of the process dying before we return the dentry */ 3426 if (pid_revalidate(dentry, 0)) 3427 return 0; 3428 out: 3429 return -ENOENT; 3430 } 3431 3432 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3433 { 3434 int result = -ENOENT; 3435 struct task_struct *task; 3436 struct task_struct *leader = get_proc_task(dir); 3437 unsigned tid; 3438 struct pid_namespace *ns; 3439 3440 if (!leader) 3441 goto out_no_task; 3442 3443 tid = name_to_int(&dentry->d_name); 3444 if (tid == ~0U) 3445 goto out; 3446 3447 ns = dentry->d_sb->s_fs_info; 3448 rcu_read_lock(); 3449 task = find_task_by_pid_ns(tid, ns); 3450 if (task) 3451 get_task_struct(task); 3452 rcu_read_unlock(); 3453 if (!task) 3454 goto out; 3455 if (!same_thread_group(leader, task)) 3456 goto out_drop_task; 3457 3458 result = proc_task_instantiate(dir, dentry, task, NULL); 3459 out_drop_task: 3460 put_task_struct(task); 3461 out: 3462 put_task_struct(leader); 3463 out_no_task: 3464 return ERR_PTR(result); 3465 } 3466 3467 /* 3468 * Find the first tid of a thread group to return to user space. 3469 * 3470 * Usually this is just the thread group leader, but if the users 3471 * buffer was too small or there was a seek into the middle of the 3472 * directory we have more work todo. 3473 * 3474 * In the case of a short read we start with find_task_by_pid. 3475 * 3476 * In the case of a seek we start with the leader and walk nr 3477 * threads past it. 3478 */ 3479 static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos, 3480 struct pid_namespace *ns) 3481 { 3482 struct task_struct *pos, *task; 3483 unsigned long nr = f_pos; 3484 3485 if (nr != f_pos) /* 32bit overflow? */ 3486 return NULL; 3487 3488 rcu_read_lock(); 3489 task = pid_task(pid, PIDTYPE_PID); 3490 if (!task) 3491 goto fail; 3492 3493 /* Attempt to start with the tid of a thread */ 3494 if (tid && nr) { 3495 pos = find_task_by_pid_ns(tid, ns); 3496 if (pos && same_thread_group(pos, task)) 3497 goto found; 3498 } 3499 3500 /* If nr exceeds the number of threads there is nothing todo */ 3501 if (nr >= get_nr_threads(task)) 3502 goto fail; 3503 3504 /* If we haven't found our starting place yet start 3505 * with the leader and walk nr threads forward. 3506 */ 3507 pos = task = task->group_leader; 3508 do { 3509 if (!nr--) 3510 goto found; 3511 } while_each_thread(task, pos); 3512 fail: 3513 pos = NULL; 3514 goto out; 3515 found: 3516 get_task_struct(pos); 3517 out: 3518 rcu_read_unlock(); 3519 return pos; 3520 } 3521 3522 /* 3523 * Find the next thread in the thread list. 3524 * Return NULL if there is an error or no next thread. 3525 * 3526 * The reference to the input task_struct is released. 3527 */ 3528 static struct task_struct *next_tid(struct task_struct *start) 3529 { 3530 struct task_struct *pos = NULL; 3531 rcu_read_lock(); 3532 if (pid_alive(start)) { 3533 pos = next_thread(start); 3534 if (thread_group_leader(pos)) 3535 pos = NULL; 3536 else 3537 get_task_struct(pos); 3538 } 3539 rcu_read_unlock(); 3540 put_task_struct(start); 3541 return pos; 3542 } 3543 3544 /* for the /proc/TGID/task/ directories */ 3545 static int proc_task_readdir(struct file *file, struct dir_context *ctx) 3546 { 3547 struct inode *inode = file_inode(file); 3548 struct task_struct *task; 3549 struct pid_namespace *ns; 3550 int tid; 3551 3552 if (proc_inode_is_dead(inode)) 3553 return -ENOENT; 3554 3555 if (!dir_emit_dots(file, ctx)) 3556 return 0; 3557 3558 /* f_version caches the tgid value that the last readdir call couldn't 3559 * return. lseek aka telldir automagically resets f_version to 0. 3560 */ 3561 ns = inode->i_sb->s_fs_info; 3562 tid = (int)file->f_version; 3563 file->f_version = 0; 3564 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns); 3565 task; 3566 task = next_tid(task), ctx->pos++) { 3567 char name[PROC_NUMBUF]; 3568 int len; 3569 tid = task_pid_nr_ns(task, ns); 3570 len = snprintf(name, sizeof(name), "%d", tid); 3571 if (!proc_fill_cache(file, ctx, name, len, 3572 proc_task_instantiate, task, NULL)) { 3573 /* returning this tgid failed, save it as the first 3574 * pid for the next readir call */ 3575 file->f_version = (u64)tid; 3576 put_task_struct(task); 3577 break; 3578 } 3579 } 3580 3581 return 0; 3582 } 3583 3584 static int proc_task_getattr(const struct path *path, struct kstat *stat, 3585 u32 request_mask, unsigned int query_flags) 3586 { 3587 struct inode *inode = d_inode(path->dentry); 3588 struct task_struct *p = get_proc_task(inode); 3589 generic_fillattr(inode, stat); 3590 3591 if (p) { 3592 stat->nlink += get_nr_threads(p); 3593 put_task_struct(p); 3594 } 3595 3596 return 0; 3597 } 3598 3599 static const struct inode_operations proc_task_inode_operations = { 3600 .lookup = proc_task_lookup, 3601 .getattr = proc_task_getattr, 3602 .setattr = proc_setattr, 3603 .permission = proc_pid_permission, 3604 }; 3605 3606 static const struct file_operations proc_task_operations = { 3607 .read = generic_read_dir, 3608 .iterate_shared = proc_task_readdir, 3609 .llseek = generic_file_llseek, 3610 }; 3611 3612 void __init set_proc_pid_nlink(void) 3613 { 3614 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3615 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3616 } 3617