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; 1364 unsigned int n; 1365 1366 err = kstrtouint_from_user(buf, count, 0, &n); 1367 if (err) 1368 return err; 1369 1370 task = get_proc_task(file_inode(file)); 1371 if (!task) 1372 return -ESRCH; 1373 WRITE_ONCE(task->fail_nth, n); 1374 put_task_struct(task); 1375 1376 return count; 1377 } 1378 1379 static ssize_t proc_fail_nth_read(struct file *file, char __user *buf, 1380 size_t count, loff_t *ppos) 1381 { 1382 struct task_struct *task; 1383 char numbuf[PROC_NUMBUF]; 1384 ssize_t len; 1385 1386 task = get_proc_task(file_inode(file)); 1387 if (!task) 1388 return -ESRCH; 1389 len = snprintf(numbuf, sizeof(numbuf), "%u\n", 1390 READ_ONCE(task->fail_nth)); 1391 len = simple_read_from_buffer(buf, count, ppos, numbuf, len); 1392 put_task_struct(task); 1393 1394 return len; 1395 } 1396 1397 static const struct file_operations proc_fail_nth_operations = { 1398 .read = proc_fail_nth_read, 1399 .write = proc_fail_nth_write, 1400 }; 1401 #endif 1402 1403 1404 #ifdef CONFIG_SCHED_DEBUG 1405 /* 1406 * Print out various scheduling related per-task fields: 1407 */ 1408 static int sched_show(struct seq_file *m, void *v) 1409 { 1410 struct inode *inode = m->private; 1411 struct task_struct *p; 1412 1413 p = get_proc_task(inode); 1414 if (!p) 1415 return -ESRCH; 1416 proc_sched_show_task(p, m); 1417 1418 put_task_struct(p); 1419 1420 return 0; 1421 } 1422 1423 static ssize_t 1424 sched_write(struct file *file, const char __user *buf, 1425 size_t count, loff_t *offset) 1426 { 1427 struct inode *inode = file_inode(file); 1428 struct task_struct *p; 1429 1430 p = get_proc_task(inode); 1431 if (!p) 1432 return -ESRCH; 1433 proc_sched_set_task(p); 1434 1435 put_task_struct(p); 1436 1437 return count; 1438 } 1439 1440 static int sched_open(struct inode *inode, struct file *filp) 1441 { 1442 return single_open(filp, sched_show, inode); 1443 } 1444 1445 static const struct file_operations proc_pid_sched_operations = { 1446 .open = sched_open, 1447 .read = seq_read, 1448 .write = sched_write, 1449 .llseek = seq_lseek, 1450 .release = single_release, 1451 }; 1452 1453 #endif 1454 1455 #ifdef CONFIG_SCHED_AUTOGROUP 1456 /* 1457 * Print out autogroup related information: 1458 */ 1459 static int sched_autogroup_show(struct seq_file *m, void *v) 1460 { 1461 struct inode *inode = m->private; 1462 struct task_struct *p; 1463 1464 p = get_proc_task(inode); 1465 if (!p) 1466 return -ESRCH; 1467 proc_sched_autogroup_show_task(p, m); 1468 1469 put_task_struct(p); 1470 1471 return 0; 1472 } 1473 1474 static ssize_t 1475 sched_autogroup_write(struct file *file, const char __user *buf, 1476 size_t count, loff_t *offset) 1477 { 1478 struct inode *inode = file_inode(file); 1479 struct task_struct *p; 1480 char buffer[PROC_NUMBUF]; 1481 int nice; 1482 int err; 1483 1484 memset(buffer, 0, sizeof(buffer)); 1485 if (count > sizeof(buffer) - 1) 1486 count = sizeof(buffer) - 1; 1487 if (copy_from_user(buffer, buf, count)) 1488 return -EFAULT; 1489 1490 err = kstrtoint(strstrip(buffer), 0, &nice); 1491 if (err < 0) 1492 return err; 1493 1494 p = get_proc_task(inode); 1495 if (!p) 1496 return -ESRCH; 1497 1498 err = proc_sched_autogroup_set_nice(p, nice); 1499 if (err) 1500 count = err; 1501 1502 put_task_struct(p); 1503 1504 return count; 1505 } 1506 1507 static int sched_autogroup_open(struct inode *inode, struct file *filp) 1508 { 1509 int ret; 1510 1511 ret = single_open(filp, sched_autogroup_show, NULL); 1512 if (!ret) { 1513 struct seq_file *m = filp->private_data; 1514 1515 m->private = inode; 1516 } 1517 return ret; 1518 } 1519 1520 static const struct file_operations proc_pid_sched_autogroup_operations = { 1521 .open = sched_autogroup_open, 1522 .read = seq_read, 1523 .write = sched_autogroup_write, 1524 .llseek = seq_lseek, 1525 .release = single_release, 1526 }; 1527 1528 #endif /* CONFIG_SCHED_AUTOGROUP */ 1529 1530 static ssize_t comm_write(struct file *file, const char __user *buf, 1531 size_t count, loff_t *offset) 1532 { 1533 struct inode *inode = file_inode(file); 1534 struct task_struct *p; 1535 char buffer[TASK_COMM_LEN]; 1536 const size_t maxlen = sizeof(buffer) - 1; 1537 1538 memset(buffer, 0, sizeof(buffer)); 1539 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count)) 1540 return -EFAULT; 1541 1542 p = get_proc_task(inode); 1543 if (!p) 1544 return -ESRCH; 1545 1546 if (same_thread_group(current, p)) 1547 set_task_comm(p, buffer); 1548 else 1549 count = -EINVAL; 1550 1551 put_task_struct(p); 1552 1553 return count; 1554 } 1555 1556 static int comm_show(struct seq_file *m, void *v) 1557 { 1558 struct inode *inode = m->private; 1559 struct task_struct *p; 1560 1561 p = get_proc_task(inode); 1562 if (!p) 1563 return -ESRCH; 1564 1565 task_lock(p); 1566 seq_printf(m, "%s\n", p->comm); 1567 task_unlock(p); 1568 1569 put_task_struct(p); 1570 1571 return 0; 1572 } 1573 1574 static int comm_open(struct inode *inode, struct file *filp) 1575 { 1576 return single_open(filp, comm_show, inode); 1577 } 1578 1579 static const struct file_operations proc_pid_set_comm_operations = { 1580 .open = comm_open, 1581 .read = seq_read, 1582 .write = comm_write, 1583 .llseek = seq_lseek, 1584 .release = single_release, 1585 }; 1586 1587 static int proc_exe_link(struct dentry *dentry, struct path *exe_path) 1588 { 1589 struct task_struct *task; 1590 struct file *exe_file; 1591 1592 task = get_proc_task(d_inode(dentry)); 1593 if (!task) 1594 return -ENOENT; 1595 exe_file = get_task_exe_file(task); 1596 put_task_struct(task); 1597 if (exe_file) { 1598 *exe_path = exe_file->f_path; 1599 path_get(&exe_file->f_path); 1600 fput(exe_file); 1601 return 0; 1602 } else 1603 return -ENOENT; 1604 } 1605 1606 static const char *proc_pid_get_link(struct dentry *dentry, 1607 struct inode *inode, 1608 struct delayed_call *done) 1609 { 1610 struct path path; 1611 int error = -EACCES; 1612 1613 if (!dentry) 1614 return ERR_PTR(-ECHILD); 1615 1616 /* Are we allowed to snoop on the tasks file descriptors? */ 1617 if (!proc_fd_access_allowed(inode)) 1618 goto out; 1619 1620 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1621 if (error) 1622 goto out; 1623 1624 nd_jump_link(&path); 1625 return NULL; 1626 out: 1627 return ERR_PTR(error); 1628 } 1629 1630 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1631 { 1632 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1633 char *pathname; 1634 int len; 1635 1636 if (!tmp) 1637 return -ENOMEM; 1638 1639 pathname = d_path(path, tmp, PAGE_SIZE); 1640 len = PTR_ERR(pathname); 1641 if (IS_ERR(pathname)) 1642 goto out; 1643 len = tmp + PAGE_SIZE - 1 - pathname; 1644 1645 if (len > buflen) 1646 len = buflen; 1647 if (copy_to_user(buffer, pathname, len)) 1648 len = -EFAULT; 1649 out: 1650 free_page((unsigned long)tmp); 1651 return len; 1652 } 1653 1654 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1655 { 1656 int error = -EACCES; 1657 struct inode *inode = d_inode(dentry); 1658 struct path path; 1659 1660 /* Are we allowed to snoop on the tasks file descriptors? */ 1661 if (!proc_fd_access_allowed(inode)) 1662 goto out; 1663 1664 error = PROC_I(inode)->op.proc_get_link(dentry, &path); 1665 if (error) 1666 goto out; 1667 1668 error = do_proc_readlink(&path, buffer, buflen); 1669 path_put(&path); 1670 out: 1671 return error; 1672 } 1673 1674 const struct inode_operations proc_pid_link_inode_operations = { 1675 .readlink = proc_pid_readlink, 1676 .get_link = proc_pid_get_link, 1677 .setattr = proc_setattr, 1678 }; 1679 1680 1681 /* building an inode */ 1682 1683 void task_dump_owner(struct task_struct *task, mode_t mode, 1684 kuid_t *ruid, kgid_t *rgid) 1685 { 1686 /* Depending on the state of dumpable compute who should own a 1687 * proc file for a task. 1688 */ 1689 const struct cred *cred; 1690 kuid_t uid; 1691 kgid_t gid; 1692 1693 /* Default to the tasks effective ownership */ 1694 rcu_read_lock(); 1695 cred = __task_cred(task); 1696 uid = cred->euid; 1697 gid = cred->egid; 1698 rcu_read_unlock(); 1699 1700 /* 1701 * Before the /proc/pid/status file was created the only way to read 1702 * the effective uid of a /process was to stat /proc/pid. Reading 1703 * /proc/pid/status is slow enough that procps and other packages 1704 * kept stating /proc/pid. To keep the rules in /proc simple I have 1705 * made this apply to all per process world readable and executable 1706 * directories. 1707 */ 1708 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) { 1709 struct mm_struct *mm; 1710 task_lock(task); 1711 mm = task->mm; 1712 /* Make non-dumpable tasks owned by some root */ 1713 if (mm) { 1714 if (get_dumpable(mm) != SUID_DUMP_USER) { 1715 struct user_namespace *user_ns = mm->user_ns; 1716 1717 uid = make_kuid(user_ns, 0); 1718 if (!uid_valid(uid)) 1719 uid = GLOBAL_ROOT_UID; 1720 1721 gid = make_kgid(user_ns, 0); 1722 if (!gid_valid(gid)) 1723 gid = GLOBAL_ROOT_GID; 1724 } 1725 } else { 1726 uid = GLOBAL_ROOT_UID; 1727 gid = GLOBAL_ROOT_GID; 1728 } 1729 task_unlock(task); 1730 } 1731 *ruid = uid; 1732 *rgid = gid; 1733 } 1734 1735 struct inode *proc_pid_make_inode(struct super_block * sb, 1736 struct task_struct *task, umode_t mode) 1737 { 1738 struct inode * inode; 1739 struct proc_inode *ei; 1740 1741 /* We need a new inode */ 1742 1743 inode = new_inode(sb); 1744 if (!inode) 1745 goto out; 1746 1747 /* Common stuff */ 1748 ei = PROC_I(inode); 1749 inode->i_mode = mode; 1750 inode->i_ino = get_next_ino(); 1751 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); 1752 inode->i_op = &proc_def_inode_operations; 1753 1754 /* 1755 * grab the reference to task. 1756 */ 1757 ei->pid = get_task_pid(task, PIDTYPE_PID); 1758 if (!ei->pid) 1759 goto out_unlock; 1760 1761 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1762 security_task_to_inode(task, inode); 1763 1764 out: 1765 return inode; 1766 1767 out_unlock: 1768 iput(inode); 1769 return NULL; 1770 } 1771 1772 int pid_getattr(const struct path *path, struct kstat *stat, 1773 u32 request_mask, unsigned int query_flags) 1774 { 1775 struct inode *inode = d_inode(path->dentry); 1776 struct task_struct *task; 1777 struct pid_namespace *pid = path->dentry->d_sb->s_fs_info; 1778 1779 generic_fillattr(inode, stat); 1780 1781 rcu_read_lock(); 1782 stat->uid = GLOBAL_ROOT_UID; 1783 stat->gid = GLOBAL_ROOT_GID; 1784 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1785 if (task) { 1786 if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) { 1787 rcu_read_unlock(); 1788 /* 1789 * This doesn't prevent learning whether PID exists, 1790 * it only makes getattr() consistent with readdir(). 1791 */ 1792 return -ENOENT; 1793 } 1794 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid); 1795 } 1796 rcu_read_unlock(); 1797 return 0; 1798 } 1799 1800 /* dentry stuff */ 1801 1802 /* 1803 * Exceptional case: normally we are not allowed to unhash a busy 1804 * directory. In this case, however, we can do it - no aliasing problems 1805 * due to the way we treat inodes. 1806 * 1807 * Rewrite the inode's ownerships here because the owning task may have 1808 * performed a setuid(), etc. 1809 * 1810 */ 1811 int pid_revalidate(struct dentry *dentry, unsigned int flags) 1812 { 1813 struct inode *inode; 1814 struct task_struct *task; 1815 1816 if (flags & LOOKUP_RCU) 1817 return -ECHILD; 1818 1819 inode = d_inode(dentry); 1820 task = get_proc_task(inode); 1821 1822 if (task) { 1823 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid); 1824 1825 inode->i_mode &= ~(S_ISUID | S_ISGID); 1826 security_task_to_inode(task, inode); 1827 put_task_struct(task); 1828 return 1; 1829 } 1830 return 0; 1831 } 1832 1833 static inline bool proc_inode_is_dead(struct inode *inode) 1834 { 1835 return !proc_pid(inode)->tasks[PIDTYPE_PID].first; 1836 } 1837 1838 int pid_delete_dentry(const struct dentry *dentry) 1839 { 1840 /* Is the task we represent dead? 1841 * If so, then don't put the dentry on the lru list, 1842 * kill it immediately. 1843 */ 1844 return proc_inode_is_dead(d_inode(dentry)); 1845 } 1846 1847 const struct dentry_operations pid_dentry_operations = 1848 { 1849 .d_revalidate = pid_revalidate, 1850 .d_delete = pid_delete_dentry, 1851 }; 1852 1853 /* Lookups */ 1854 1855 /* 1856 * Fill a directory entry. 1857 * 1858 * If possible create the dcache entry and derive our inode number and 1859 * file type from dcache entry. 1860 * 1861 * Since all of the proc inode numbers are dynamically generated, the inode 1862 * numbers do not exist until the inode is cache. This means creating the 1863 * the dcache entry in readdir is necessary to keep the inode numbers 1864 * reported by readdir in sync with the inode numbers reported 1865 * by stat. 1866 */ 1867 bool proc_fill_cache(struct file *file, struct dir_context *ctx, 1868 const char *name, int len, 1869 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1870 { 1871 struct dentry *child, *dir = file->f_path.dentry; 1872 struct qstr qname = QSTR_INIT(name, len); 1873 struct inode *inode; 1874 unsigned type; 1875 ino_t ino; 1876 1877 child = d_hash_and_lookup(dir, &qname); 1878 if (!child) { 1879 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); 1880 child = d_alloc_parallel(dir, &qname, &wq); 1881 if (IS_ERR(child)) 1882 goto end_instantiate; 1883 if (d_in_lookup(child)) { 1884 int err = instantiate(d_inode(dir), child, task, ptr); 1885 d_lookup_done(child); 1886 if (err < 0) { 1887 dput(child); 1888 goto end_instantiate; 1889 } 1890 } 1891 } 1892 inode = d_inode(child); 1893 ino = inode->i_ino; 1894 type = inode->i_mode >> 12; 1895 dput(child); 1896 return dir_emit(ctx, name, len, ino, type); 1897 1898 end_instantiate: 1899 return dir_emit(ctx, name, len, 1, DT_UNKNOWN); 1900 } 1901 1902 /* 1903 * dname_to_vma_addr - maps a dentry name into two unsigned longs 1904 * which represent vma start and end addresses. 1905 */ 1906 static int dname_to_vma_addr(struct dentry *dentry, 1907 unsigned long *start, unsigned long *end) 1908 { 1909 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2) 1910 return -EINVAL; 1911 1912 return 0; 1913 } 1914 1915 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags) 1916 { 1917 unsigned long vm_start, vm_end; 1918 bool exact_vma_exists = false; 1919 struct mm_struct *mm = NULL; 1920 struct task_struct *task; 1921 struct inode *inode; 1922 int status = 0; 1923 1924 if (flags & LOOKUP_RCU) 1925 return -ECHILD; 1926 1927 inode = d_inode(dentry); 1928 task = get_proc_task(inode); 1929 if (!task) 1930 goto out_notask; 1931 1932 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); 1933 if (IS_ERR_OR_NULL(mm)) 1934 goto out; 1935 1936 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) { 1937 down_read(&mm->mmap_sem); 1938 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end); 1939 up_read(&mm->mmap_sem); 1940 } 1941 1942 mmput(mm); 1943 1944 if (exact_vma_exists) { 1945 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid); 1946 1947 security_task_to_inode(task, inode); 1948 status = 1; 1949 } 1950 1951 out: 1952 put_task_struct(task); 1953 1954 out_notask: 1955 return status; 1956 } 1957 1958 static const struct dentry_operations tid_map_files_dentry_operations = { 1959 .d_revalidate = map_files_d_revalidate, 1960 .d_delete = pid_delete_dentry, 1961 }; 1962 1963 static int map_files_get_link(struct dentry *dentry, struct path *path) 1964 { 1965 unsigned long vm_start, vm_end; 1966 struct vm_area_struct *vma; 1967 struct task_struct *task; 1968 struct mm_struct *mm; 1969 int rc; 1970 1971 rc = -ENOENT; 1972 task = get_proc_task(d_inode(dentry)); 1973 if (!task) 1974 goto out; 1975 1976 mm = get_task_mm(task); 1977 put_task_struct(task); 1978 if (!mm) 1979 goto out; 1980 1981 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end); 1982 if (rc) 1983 goto out_mmput; 1984 1985 rc = -ENOENT; 1986 down_read(&mm->mmap_sem); 1987 vma = find_exact_vma(mm, vm_start, vm_end); 1988 if (vma && vma->vm_file) { 1989 *path = vma->vm_file->f_path; 1990 path_get(path); 1991 rc = 0; 1992 } 1993 up_read(&mm->mmap_sem); 1994 1995 out_mmput: 1996 mmput(mm); 1997 out: 1998 return rc; 1999 } 2000 2001 struct map_files_info { 2002 fmode_t mode; 2003 unsigned int len; 2004 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */ 2005 }; 2006 2007 /* 2008 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the 2009 * symlinks may be used to bypass permissions on ancestor directories in the 2010 * path to the file in question. 2011 */ 2012 static const char * 2013 proc_map_files_get_link(struct dentry *dentry, 2014 struct inode *inode, 2015 struct delayed_call *done) 2016 { 2017 if (!capable(CAP_SYS_ADMIN)) 2018 return ERR_PTR(-EPERM); 2019 2020 return proc_pid_get_link(dentry, inode, done); 2021 } 2022 2023 /* 2024 * Identical to proc_pid_link_inode_operations except for get_link() 2025 */ 2026 static const struct inode_operations proc_map_files_link_inode_operations = { 2027 .readlink = proc_pid_readlink, 2028 .get_link = proc_map_files_get_link, 2029 .setattr = proc_setattr, 2030 }; 2031 2032 static int 2033 proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, 2034 struct task_struct *task, const void *ptr) 2035 { 2036 fmode_t mode = (fmode_t)(unsigned long)ptr; 2037 struct proc_inode *ei; 2038 struct inode *inode; 2039 2040 inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK | 2041 ((mode & FMODE_READ ) ? S_IRUSR : 0) | 2042 ((mode & FMODE_WRITE) ? S_IWUSR : 0)); 2043 if (!inode) 2044 return -ENOENT; 2045 2046 ei = PROC_I(inode); 2047 ei->op.proc_get_link = map_files_get_link; 2048 2049 inode->i_op = &proc_map_files_link_inode_operations; 2050 inode->i_size = 64; 2051 2052 d_set_d_op(dentry, &tid_map_files_dentry_operations); 2053 d_add(dentry, inode); 2054 2055 return 0; 2056 } 2057 2058 static struct dentry *proc_map_files_lookup(struct inode *dir, 2059 struct dentry *dentry, unsigned int flags) 2060 { 2061 unsigned long vm_start, vm_end; 2062 struct vm_area_struct *vma; 2063 struct task_struct *task; 2064 int result; 2065 struct mm_struct *mm; 2066 2067 result = -ENOENT; 2068 task = get_proc_task(dir); 2069 if (!task) 2070 goto out; 2071 2072 result = -EACCES; 2073 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2074 goto out_put_task; 2075 2076 result = -ENOENT; 2077 if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) 2078 goto out_put_task; 2079 2080 mm = get_task_mm(task); 2081 if (!mm) 2082 goto out_put_task; 2083 2084 down_read(&mm->mmap_sem); 2085 vma = find_exact_vma(mm, vm_start, vm_end); 2086 if (!vma) 2087 goto out_no_vma; 2088 2089 if (vma->vm_file) 2090 result = proc_map_files_instantiate(dir, dentry, task, 2091 (void *)(unsigned long)vma->vm_file->f_mode); 2092 2093 out_no_vma: 2094 up_read(&mm->mmap_sem); 2095 mmput(mm); 2096 out_put_task: 2097 put_task_struct(task); 2098 out: 2099 return ERR_PTR(result); 2100 } 2101 2102 static const struct inode_operations proc_map_files_inode_operations = { 2103 .lookup = proc_map_files_lookup, 2104 .permission = proc_fd_permission, 2105 .setattr = proc_setattr, 2106 }; 2107 2108 static int 2109 proc_map_files_readdir(struct file *file, struct dir_context *ctx) 2110 { 2111 struct vm_area_struct *vma; 2112 struct task_struct *task; 2113 struct mm_struct *mm; 2114 unsigned long nr_files, pos, i; 2115 struct flex_array *fa = NULL; 2116 struct map_files_info info; 2117 struct map_files_info *p; 2118 int ret; 2119 2120 ret = -ENOENT; 2121 task = get_proc_task(file_inode(file)); 2122 if (!task) 2123 goto out; 2124 2125 ret = -EACCES; 2126 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) 2127 goto out_put_task; 2128 2129 ret = 0; 2130 if (!dir_emit_dots(file, ctx)) 2131 goto out_put_task; 2132 2133 mm = get_task_mm(task); 2134 if (!mm) 2135 goto out_put_task; 2136 down_read(&mm->mmap_sem); 2137 2138 nr_files = 0; 2139 2140 /* 2141 * We need two passes here: 2142 * 2143 * 1) Collect vmas of mapped files with mmap_sem taken 2144 * 2) Release mmap_sem and instantiate entries 2145 * 2146 * otherwise we get lockdep complained, since filldir() 2147 * routine might require mmap_sem taken in might_fault(). 2148 */ 2149 2150 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { 2151 if (vma->vm_file && ++pos > ctx->pos) 2152 nr_files++; 2153 } 2154 2155 if (nr_files) { 2156 fa = flex_array_alloc(sizeof(info), nr_files, 2157 GFP_KERNEL); 2158 if (!fa || flex_array_prealloc(fa, 0, nr_files, 2159 GFP_KERNEL)) { 2160 ret = -ENOMEM; 2161 if (fa) 2162 flex_array_free(fa); 2163 up_read(&mm->mmap_sem); 2164 mmput(mm); 2165 goto out_put_task; 2166 } 2167 for (i = 0, vma = mm->mmap, pos = 2; vma; 2168 vma = vma->vm_next) { 2169 if (!vma->vm_file) 2170 continue; 2171 if (++pos <= ctx->pos) 2172 continue; 2173 2174 info.mode = vma->vm_file->f_mode; 2175 info.len = snprintf(info.name, 2176 sizeof(info.name), "%lx-%lx", 2177 vma->vm_start, vma->vm_end); 2178 if (flex_array_put(fa, i++, &info, GFP_KERNEL)) 2179 BUG(); 2180 } 2181 } 2182 up_read(&mm->mmap_sem); 2183 2184 for (i = 0; i < nr_files; i++) { 2185 p = flex_array_get(fa, i); 2186 if (!proc_fill_cache(file, ctx, 2187 p->name, p->len, 2188 proc_map_files_instantiate, 2189 task, 2190 (void *)(unsigned long)p->mode)) 2191 break; 2192 ctx->pos++; 2193 } 2194 if (fa) 2195 flex_array_free(fa); 2196 mmput(mm); 2197 2198 out_put_task: 2199 put_task_struct(task); 2200 out: 2201 return ret; 2202 } 2203 2204 static const struct file_operations proc_map_files_operations = { 2205 .read = generic_read_dir, 2206 .iterate_shared = proc_map_files_readdir, 2207 .llseek = generic_file_llseek, 2208 }; 2209 2210 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 2211 struct timers_private { 2212 struct pid *pid; 2213 struct task_struct *task; 2214 struct sighand_struct *sighand; 2215 struct pid_namespace *ns; 2216 unsigned long flags; 2217 }; 2218 2219 static void *timers_start(struct seq_file *m, loff_t *pos) 2220 { 2221 struct timers_private *tp = m->private; 2222 2223 tp->task = get_pid_task(tp->pid, PIDTYPE_PID); 2224 if (!tp->task) 2225 return ERR_PTR(-ESRCH); 2226 2227 tp->sighand = lock_task_sighand(tp->task, &tp->flags); 2228 if (!tp->sighand) 2229 return ERR_PTR(-ESRCH); 2230 2231 return seq_list_start(&tp->task->signal->posix_timers, *pos); 2232 } 2233 2234 static void *timers_next(struct seq_file *m, void *v, loff_t *pos) 2235 { 2236 struct timers_private *tp = m->private; 2237 return seq_list_next(v, &tp->task->signal->posix_timers, pos); 2238 } 2239 2240 static void timers_stop(struct seq_file *m, void *v) 2241 { 2242 struct timers_private *tp = m->private; 2243 2244 if (tp->sighand) { 2245 unlock_task_sighand(tp->task, &tp->flags); 2246 tp->sighand = NULL; 2247 } 2248 2249 if (tp->task) { 2250 put_task_struct(tp->task); 2251 tp->task = NULL; 2252 } 2253 } 2254 2255 static int show_timer(struct seq_file *m, void *v) 2256 { 2257 struct k_itimer *timer; 2258 struct timers_private *tp = m->private; 2259 int notify; 2260 static const char * const nstr[] = { 2261 [SIGEV_SIGNAL] = "signal", 2262 [SIGEV_NONE] = "none", 2263 [SIGEV_THREAD] = "thread", 2264 }; 2265 2266 timer = list_entry((struct list_head *)v, struct k_itimer, list); 2267 notify = timer->it_sigev_notify; 2268 2269 seq_printf(m, "ID: %d\n", timer->it_id); 2270 seq_printf(m, "signal: %d/%p\n", 2271 timer->sigq->info.si_signo, 2272 timer->sigq->info.si_value.sival_ptr); 2273 seq_printf(m, "notify: %s/%s.%d\n", 2274 nstr[notify & ~SIGEV_THREAD_ID], 2275 (notify & SIGEV_THREAD_ID) ? "tid" : "pid", 2276 pid_nr_ns(timer->it_pid, tp->ns)); 2277 seq_printf(m, "ClockID: %d\n", timer->it_clock); 2278 2279 return 0; 2280 } 2281 2282 static const struct seq_operations proc_timers_seq_ops = { 2283 .start = timers_start, 2284 .next = timers_next, 2285 .stop = timers_stop, 2286 .show = show_timer, 2287 }; 2288 2289 static int proc_timers_open(struct inode *inode, struct file *file) 2290 { 2291 struct timers_private *tp; 2292 2293 tp = __seq_open_private(file, &proc_timers_seq_ops, 2294 sizeof(struct timers_private)); 2295 if (!tp) 2296 return -ENOMEM; 2297 2298 tp->pid = proc_pid(inode); 2299 tp->ns = inode->i_sb->s_fs_info; 2300 return 0; 2301 } 2302 2303 static const struct file_operations proc_timers_operations = { 2304 .open = proc_timers_open, 2305 .read = seq_read, 2306 .llseek = seq_lseek, 2307 .release = seq_release_private, 2308 }; 2309 #endif 2310 2311 static ssize_t timerslack_ns_write(struct file *file, const char __user *buf, 2312 size_t count, loff_t *offset) 2313 { 2314 struct inode *inode = file_inode(file); 2315 struct task_struct *p; 2316 u64 slack_ns; 2317 int err; 2318 2319 err = kstrtoull_from_user(buf, count, 10, &slack_ns); 2320 if (err < 0) 2321 return err; 2322 2323 p = get_proc_task(inode); 2324 if (!p) 2325 return -ESRCH; 2326 2327 if (p != current) { 2328 if (!capable(CAP_SYS_NICE)) { 2329 count = -EPERM; 2330 goto out; 2331 } 2332 2333 err = security_task_setscheduler(p); 2334 if (err) { 2335 count = err; 2336 goto out; 2337 } 2338 } 2339 2340 task_lock(p); 2341 if (slack_ns == 0) 2342 p->timer_slack_ns = p->default_timer_slack_ns; 2343 else 2344 p->timer_slack_ns = slack_ns; 2345 task_unlock(p); 2346 2347 out: 2348 put_task_struct(p); 2349 2350 return count; 2351 } 2352 2353 static int timerslack_ns_show(struct seq_file *m, void *v) 2354 { 2355 struct inode *inode = m->private; 2356 struct task_struct *p; 2357 int err = 0; 2358 2359 p = get_proc_task(inode); 2360 if (!p) 2361 return -ESRCH; 2362 2363 if (p != current) { 2364 2365 if (!capable(CAP_SYS_NICE)) { 2366 err = -EPERM; 2367 goto out; 2368 } 2369 err = security_task_getscheduler(p); 2370 if (err) 2371 goto out; 2372 } 2373 2374 task_lock(p); 2375 seq_printf(m, "%llu\n", p->timer_slack_ns); 2376 task_unlock(p); 2377 2378 out: 2379 put_task_struct(p); 2380 2381 return err; 2382 } 2383 2384 static int timerslack_ns_open(struct inode *inode, struct file *filp) 2385 { 2386 return single_open(filp, timerslack_ns_show, inode); 2387 } 2388 2389 static const struct file_operations proc_pid_set_timerslack_ns_operations = { 2390 .open = timerslack_ns_open, 2391 .read = seq_read, 2392 .write = timerslack_ns_write, 2393 .llseek = seq_lseek, 2394 .release = single_release, 2395 }; 2396 2397 static int proc_pident_instantiate(struct inode *dir, 2398 struct dentry *dentry, struct task_struct *task, const void *ptr) 2399 { 2400 const struct pid_entry *p = ptr; 2401 struct inode *inode; 2402 struct proc_inode *ei; 2403 2404 inode = proc_pid_make_inode(dir->i_sb, task, p->mode); 2405 if (!inode) 2406 goto out; 2407 2408 ei = PROC_I(inode); 2409 if (S_ISDIR(inode->i_mode)) 2410 set_nlink(inode, 2); /* Use getattr to fix if necessary */ 2411 if (p->iop) 2412 inode->i_op = p->iop; 2413 if (p->fop) 2414 inode->i_fop = p->fop; 2415 ei->op = p->op; 2416 d_set_d_op(dentry, &pid_dentry_operations); 2417 d_add(dentry, inode); 2418 /* Close the race of the process dying before we return the dentry */ 2419 if (pid_revalidate(dentry, 0)) 2420 return 0; 2421 out: 2422 return -ENOENT; 2423 } 2424 2425 static struct dentry *proc_pident_lookup(struct inode *dir, 2426 struct dentry *dentry, 2427 const struct pid_entry *ents, 2428 unsigned int nents) 2429 { 2430 int error; 2431 struct task_struct *task = get_proc_task(dir); 2432 const struct pid_entry *p, *last; 2433 2434 error = -ENOENT; 2435 2436 if (!task) 2437 goto out_no_task; 2438 2439 /* 2440 * Yes, it does not scale. And it should not. Don't add 2441 * new entries into /proc/<tgid>/ without very good reasons. 2442 */ 2443 last = &ents[nents]; 2444 for (p = ents; p < last; p++) { 2445 if (p->len != dentry->d_name.len) 2446 continue; 2447 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2448 break; 2449 } 2450 if (p >= last) 2451 goto out; 2452 2453 error = proc_pident_instantiate(dir, dentry, task, p); 2454 out: 2455 put_task_struct(task); 2456 out_no_task: 2457 return ERR_PTR(error); 2458 } 2459 2460 static int proc_pident_readdir(struct file *file, struct dir_context *ctx, 2461 const struct pid_entry *ents, unsigned int nents) 2462 { 2463 struct task_struct *task = get_proc_task(file_inode(file)); 2464 const struct pid_entry *p; 2465 2466 if (!task) 2467 return -ENOENT; 2468 2469 if (!dir_emit_dots(file, ctx)) 2470 goto out; 2471 2472 if (ctx->pos >= nents + 2) 2473 goto out; 2474 2475 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) { 2476 if (!proc_fill_cache(file, ctx, p->name, p->len, 2477 proc_pident_instantiate, task, p)) 2478 break; 2479 ctx->pos++; 2480 } 2481 out: 2482 put_task_struct(task); 2483 return 0; 2484 } 2485 2486 #ifdef CONFIG_SECURITY 2487 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2488 size_t count, loff_t *ppos) 2489 { 2490 struct inode * inode = file_inode(file); 2491 char *p = NULL; 2492 ssize_t length; 2493 struct task_struct *task = get_proc_task(inode); 2494 2495 if (!task) 2496 return -ESRCH; 2497 2498 length = security_getprocattr(task, 2499 (char*)file->f_path.dentry->d_name.name, 2500 &p); 2501 put_task_struct(task); 2502 if (length > 0) 2503 length = simple_read_from_buffer(buf, count, ppos, p, length); 2504 kfree(p); 2505 return length; 2506 } 2507 2508 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2509 size_t count, loff_t *ppos) 2510 { 2511 struct inode * inode = file_inode(file); 2512 void *page; 2513 ssize_t length; 2514 struct task_struct *task = get_proc_task(inode); 2515 2516 length = -ESRCH; 2517 if (!task) 2518 goto out_no_task; 2519 2520 /* A task may only write its own attributes. */ 2521 length = -EACCES; 2522 if (current != task) 2523 goto out; 2524 2525 if (count > PAGE_SIZE) 2526 count = PAGE_SIZE; 2527 2528 /* No partial writes. */ 2529 length = -EINVAL; 2530 if (*ppos != 0) 2531 goto out; 2532 2533 page = memdup_user(buf, count); 2534 if (IS_ERR(page)) { 2535 length = PTR_ERR(page); 2536 goto out; 2537 } 2538 2539 /* Guard against adverse ptrace interaction */ 2540 length = mutex_lock_interruptible(¤t->signal->cred_guard_mutex); 2541 if (length < 0) 2542 goto out_free; 2543 2544 length = security_setprocattr(file->f_path.dentry->d_name.name, 2545 page, count); 2546 mutex_unlock(¤t->signal->cred_guard_mutex); 2547 out_free: 2548 kfree(page); 2549 out: 2550 put_task_struct(task); 2551 out_no_task: 2552 return length; 2553 } 2554 2555 static const struct file_operations proc_pid_attr_operations = { 2556 .read = proc_pid_attr_read, 2557 .write = proc_pid_attr_write, 2558 .llseek = generic_file_llseek, 2559 }; 2560 2561 static const struct pid_entry attr_dir_stuff[] = { 2562 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2563 REG("prev", S_IRUGO, proc_pid_attr_operations), 2564 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2565 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2566 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2567 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2568 }; 2569 2570 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) 2571 { 2572 return proc_pident_readdir(file, ctx, 2573 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2574 } 2575 2576 static const struct file_operations proc_attr_dir_operations = { 2577 .read = generic_read_dir, 2578 .iterate_shared = proc_attr_dir_readdir, 2579 .llseek = generic_file_llseek, 2580 }; 2581 2582 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2583 struct dentry *dentry, unsigned int flags) 2584 { 2585 return proc_pident_lookup(dir, dentry, 2586 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2587 } 2588 2589 static const struct inode_operations proc_attr_dir_inode_operations = { 2590 .lookup = proc_attr_dir_lookup, 2591 .getattr = pid_getattr, 2592 .setattr = proc_setattr, 2593 }; 2594 2595 #endif 2596 2597 #ifdef CONFIG_ELF_CORE 2598 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2599 size_t count, loff_t *ppos) 2600 { 2601 struct task_struct *task = get_proc_task(file_inode(file)); 2602 struct mm_struct *mm; 2603 char buffer[PROC_NUMBUF]; 2604 size_t len; 2605 int ret; 2606 2607 if (!task) 2608 return -ESRCH; 2609 2610 ret = 0; 2611 mm = get_task_mm(task); 2612 if (mm) { 2613 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2614 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2615 MMF_DUMP_FILTER_SHIFT)); 2616 mmput(mm); 2617 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2618 } 2619 2620 put_task_struct(task); 2621 2622 return ret; 2623 } 2624 2625 static ssize_t proc_coredump_filter_write(struct file *file, 2626 const char __user *buf, 2627 size_t count, 2628 loff_t *ppos) 2629 { 2630 struct task_struct *task; 2631 struct mm_struct *mm; 2632 unsigned int val; 2633 int ret; 2634 int i; 2635 unsigned long mask; 2636 2637 ret = kstrtouint_from_user(buf, count, 0, &val); 2638 if (ret < 0) 2639 return ret; 2640 2641 ret = -ESRCH; 2642 task = get_proc_task(file_inode(file)); 2643 if (!task) 2644 goto out_no_task; 2645 2646 mm = get_task_mm(task); 2647 if (!mm) 2648 goto out_no_mm; 2649 ret = 0; 2650 2651 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2652 if (val & mask) 2653 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2654 else 2655 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2656 } 2657 2658 mmput(mm); 2659 out_no_mm: 2660 put_task_struct(task); 2661 out_no_task: 2662 if (ret < 0) 2663 return ret; 2664 return count; 2665 } 2666 2667 static const struct file_operations proc_coredump_filter_operations = { 2668 .read = proc_coredump_filter_read, 2669 .write = proc_coredump_filter_write, 2670 .llseek = generic_file_llseek, 2671 }; 2672 #endif 2673 2674 #ifdef CONFIG_TASK_IO_ACCOUNTING 2675 static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole) 2676 { 2677 struct task_io_accounting acct = task->ioac; 2678 unsigned long flags; 2679 int result; 2680 2681 result = mutex_lock_killable(&task->signal->cred_guard_mutex); 2682 if (result) 2683 return result; 2684 2685 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) { 2686 result = -EACCES; 2687 goto out_unlock; 2688 } 2689 2690 if (whole && lock_task_sighand(task, &flags)) { 2691 struct task_struct *t = task; 2692 2693 task_io_accounting_add(&acct, &task->signal->ioac); 2694 while_each_thread(task, t) 2695 task_io_accounting_add(&acct, &t->ioac); 2696 2697 unlock_task_sighand(task, &flags); 2698 } 2699 seq_printf(m, 2700 "rchar: %llu\n" 2701 "wchar: %llu\n" 2702 "syscr: %llu\n" 2703 "syscw: %llu\n" 2704 "read_bytes: %llu\n" 2705 "write_bytes: %llu\n" 2706 "cancelled_write_bytes: %llu\n", 2707 (unsigned long long)acct.rchar, 2708 (unsigned long long)acct.wchar, 2709 (unsigned long long)acct.syscr, 2710 (unsigned long long)acct.syscw, 2711 (unsigned long long)acct.read_bytes, 2712 (unsigned long long)acct.write_bytes, 2713 (unsigned long long)acct.cancelled_write_bytes); 2714 result = 0; 2715 2716 out_unlock: 2717 mutex_unlock(&task->signal->cred_guard_mutex); 2718 return result; 2719 } 2720 2721 static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2722 struct pid *pid, struct task_struct *task) 2723 { 2724 return do_io_accounting(task, m, 0); 2725 } 2726 2727 static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns, 2728 struct pid *pid, struct task_struct *task) 2729 { 2730 return do_io_accounting(task, m, 1); 2731 } 2732 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 2733 2734 #ifdef CONFIG_USER_NS 2735 static int proc_id_map_open(struct inode *inode, struct file *file, 2736 const struct seq_operations *seq_ops) 2737 { 2738 struct user_namespace *ns = NULL; 2739 struct task_struct *task; 2740 struct seq_file *seq; 2741 int ret = -EINVAL; 2742 2743 task = get_proc_task(inode); 2744 if (task) { 2745 rcu_read_lock(); 2746 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2747 rcu_read_unlock(); 2748 put_task_struct(task); 2749 } 2750 if (!ns) 2751 goto err; 2752 2753 ret = seq_open(file, seq_ops); 2754 if (ret) 2755 goto err_put_ns; 2756 2757 seq = file->private_data; 2758 seq->private = ns; 2759 2760 return 0; 2761 err_put_ns: 2762 put_user_ns(ns); 2763 err: 2764 return ret; 2765 } 2766 2767 static int proc_id_map_release(struct inode *inode, struct file *file) 2768 { 2769 struct seq_file *seq = file->private_data; 2770 struct user_namespace *ns = seq->private; 2771 put_user_ns(ns); 2772 return seq_release(inode, file); 2773 } 2774 2775 static int proc_uid_map_open(struct inode *inode, struct file *file) 2776 { 2777 return proc_id_map_open(inode, file, &proc_uid_seq_operations); 2778 } 2779 2780 static int proc_gid_map_open(struct inode *inode, struct file *file) 2781 { 2782 return proc_id_map_open(inode, file, &proc_gid_seq_operations); 2783 } 2784 2785 static int proc_projid_map_open(struct inode *inode, struct file *file) 2786 { 2787 return proc_id_map_open(inode, file, &proc_projid_seq_operations); 2788 } 2789 2790 static const struct file_operations proc_uid_map_operations = { 2791 .open = proc_uid_map_open, 2792 .write = proc_uid_map_write, 2793 .read = seq_read, 2794 .llseek = seq_lseek, 2795 .release = proc_id_map_release, 2796 }; 2797 2798 static const struct file_operations proc_gid_map_operations = { 2799 .open = proc_gid_map_open, 2800 .write = proc_gid_map_write, 2801 .read = seq_read, 2802 .llseek = seq_lseek, 2803 .release = proc_id_map_release, 2804 }; 2805 2806 static const struct file_operations proc_projid_map_operations = { 2807 .open = proc_projid_map_open, 2808 .write = proc_projid_map_write, 2809 .read = seq_read, 2810 .llseek = seq_lseek, 2811 .release = proc_id_map_release, 2812 }; 2813 2814 static int proc_setgroups_open(struct inode *inode, struct file *file) 2815 { 2816 struct user_namespace *ns = NULL; 2817 struct task_struct *task; 2818 int ret; 2819 2820 ret = -ESRCH; 2821 task = get_proc_task(inode); 2822 if (task) { 2823 rcu_read_lock(); 2824 ns = get_user_ns(task_cred_xxx(task, user_ns)); 2825 rcu_read_unlock(); 2826 put_task_struct(task); 2827 } 2828 if (!ns) 2829 goto err; 2830 2831 if (file->f_mode & FMODE_WRITE) { 2832 ret = -EACCES; 2833 if (!ns_capable(ns, CAP_SYS_ADMIN)) 2834 goto err_put_ns; 2835 } 2836 2837 ret = single_open(file, &proc_setgroups_show, ns); 2838 if (ret) 2839 goto err_put_ns; 2840 2841 return 0; 2842 err_put_ns: 2843 put_user_ns(ns); 2844 err: 2845 return ret; 2846 } 2847 2848 static int proc_setgroups_release(struct inode *inode, struct file *file) 2849 { 2850 struct seq_file *seq = file->private_data; 2851 struct user_namespace *ns = seq->private; 2852 int ret = single_release(inode, file); 2853 put_user_ns(ns); 2854 return ret; 2855 } 2856 2857 static const struct file_operations proc_setgroups_operations = { 2858 .open = proc_setgroups_open, 2859 .write = proc_setgroups_write, 2860 .read = seq_read, 2861 .llseek = seq_lseek, 2862 .release = proc_setgroups_release, 2863 }; 2864 #endif /* CONFIG_USER_NS */ 2865 2866 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, 2867 struct pid *pid, struct task_struct *task) 2868 { 2869 int err = lock_trace(task); 2870 if (!err) { 2871 seq_printf(m, "%08x\n", task->personality); 2872 unlock_trace(task); 2873 } 2874 return err; 2875 } 2876 2877 #ifdef CONFIG_LIVEPATCH 2878 static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns, 2879 struct pid *pid, struct task_struct *task) 2880 { 2881 seq_printf(m, "%d\n", task->patch_state); 2882 return 0; 2883 } 2884 #endif /* CONFIG_LIVEPATCH */ 2885 2886 /* 2887 * Thread groups 2888 */ 2889 static const struct file_operations proc_task_operations; 2890 static const struct inode_operations proc_task_inode_operations; 2891 2892 static const struct pid_entry tgid_base_stuff[] = { 2893 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2894 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2895 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations), 2896 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2897 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 2898 #ifdef CONFIG_NET 2899 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2900 #endif 2901 REG("environ", S_IRUSR, proc_environ_operations), 2902 REG("auxv", S_IRUSR, proc_auxv_operations), 2903 ONE("status", S_IRUGO, proc_pid_status), 2904 ONE("personality", S_IRUSR, proc_pid_personality), 2905 ONE("limits", S_IRUGO, proc_pid_limits), 2906 #ifdef CONFIG_SCHED_DEBUG 2907 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2908 #endif 2909 #ifdef CONFIG_SCHED_AUTOGROUP 2910 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), 2911 #endif 2912 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2913 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2914 ONE("syscall", S_IRUSR, proc_pid_syscall), 2915 #endif 2916 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 2917 ONE("stat", S_IRUGO, proc_tgid_stat), 2918 ONE("statm", S_IRUGO, proc_pid_statm), 2919 REG("maps", S_IRUGO, proc_pid_maps_operations), 2920 #ifdef CONFIG_NUMA 2921 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations), 2922 #endif 2923 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2924 LNK("cwd", proc_cwd_link), 2925 LNK("root", proc_root_link), 2926 LNK("exe", proc_exe_link), 2927 REG("mounts", S_IRUGO, proc_mounts_operations), 2928 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2929 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2930 #ifdef CONFIG_PROC_PAGE_MONITOR 2931 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2932 REG("smaps", S_IRUGO, proc_pid_smaps_operations), 2933 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2934 #endif 2935 #ifdef CONFIG_SECURITY 2936 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2937 #endif 2938 #ifdef CONFIG_KALLSYMS 2939 ONE("wchan", S_IRUGO, proc_pid_wchan), 2940 #endif 2941 #ifdef CONFIG_STACKTRACE 2942 ONE("stack", S_IRUSR, proc_pid_stack), 2943 #endif 2944 #ifdef CONFIG_SCHED_INFO 2945 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 2946 #endif 2947 #ifdef CONFIG_LATENCYTOP 2948 REG("latency", S_IRUGO, proc_lstats_operations), 2949 #endif 2950 #ifdef CONFIG_PROC_PID_CPUSET 2951 ONE("cpuset", S_IRUGO, proc_cpuset_show), 2952 #endif 2953 #ifdef CONFIG_CGROUPS 2954 ONE("cgroup", S_IRUGO, proc_cgroup_show), 2955 #endif 2956 ONE("oom_score", S_IRUGO, proc_oom_score), 2957 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 2958 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 2959 #ifdef CONFIG_AUDITSYSCALL 2960 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2961 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2962 #endif 2963 #ifdef CONFIG_FAULT_INJECTION 2964 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2965 REG("fail-nth", 0644, proc_fail_nth_operations), 2966 #endif 2967 #ifdef CONFIG_ELF_CORE 2968 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2969 #endif 2970 #ifdef CONFIG_TASK_IO_ACCOUNTING 2971 ONE("io", S_IRUSR, proc_tgid_io_accounting), 2972 #endif 2973 #ifdef CONFIG_HARDWALL 2974 ONE("hardwall", S_IRUGO, proc_pid_hardwall), 2975 #endif 2976 #ifdef CONFIG_USER_NS 2977 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 2978 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 2979 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 2980 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 2981 #endif 2982 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS) 2983 REG("timers", S_IRUGO, proc_timers_operations), 2984 #endif 2985 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations), 2986 #ifdef CONFIG_LIVEPATCH 2987 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 2988 #endif 2989 }; 2990 2991 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) 2992 { 2993 return proc_pident_readdir(file, ctx, 2994 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2995 } 2996 2997 static const struct file_operations proc_tgid_base_operations = { 2998 .read = generic_read_dir, 2999 .iterate_shared = proc_tgid_base_readdir, 3000 .llseek = generic_file_llseek, 3001 }; 3002 3003 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3004 { 3005 return proc_pident_lookup(dir, dentry, 3006 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3007 } 3008 3009 static const struct inode_operations proc_tgid_base_inode_operations = { 3010 .lookup = proc_tgid_base_lookup, 3011 .getattr = pid_getattr, 3012 .setattr = proc_setattr, 3013 .permission = proc_pid_permission, 3014 }; 3015 3016 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 3017 { 3018 struct dentry *dentry, *leader, *dir; 3019 char buf[PROC_NUMBUF]; 3020 struct qstr name; 3021 3022 name.name = buf; 3023 name.len = snprintf(buf, sizeof(buf), "%d", pid); 3024 /* no ->d_hash() rejects on procfs */ 3025 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 3026 if (dentry) { 3027 d_invalidate(dentry); 3028 dput(dentry); 3029 } 3030 3031 if (pid == tgid) 3032 return; 3033 3034 name.name = buf; 3035 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 3036 leader = d_hash_and_lookup(mnt->mnt_root, &name); 3037 if (!leader) 3038 goto out; 3039 3040 name.name = "task"; 3041 name.len = strlen(name.name); 3042 dir = d_hash_and_lookup(leader, &name); 3043 if (!dir) 3044 goto out_put_leader; 3045 3046 name.name = buf; 3047 name.len = snprintf(buf, sizeof(buf), "%d", pid); 3048 dentry = d_hash_and_lookup(dir, &name); 3049 if (dentry) { 3050 d_invalidate(dentry); 3051 dput(dentry); 3052 } 3053 3054 dput(dir); 3055 out_put_leader: 3056 dput(leader); 3057 out: 3058 return; 3059 } 3060 3061 /** 3062 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 3063 * @task: task that should be flushed. 3064 * 3065 * When flushing dentries from proc, one needs to flush them from global 3066 * proc (proc_mnt) and from all the namespaces' procs this task was seen 3067 * in. This call is supposed to do all of this job. 3068 * 3069 * Looks in the dcache for 3070 * /proc/@pid 3071 * /proc/@tgid/task/@pid 3072 * if either directory is present flushes it and all of it'ts children 3073 * from the dcache. 3074 * 3075 * It is safe and reasonable to cache /proc entries for a task until 3076 * that task exits. After that they just clog up the dcache with 3077 * useless entries, possibly causing useful dcache entries to be 3078 * flushed instead. This routine is proved to flush those useless 3079 * dcache entries at process exit time. 3080 * 3081 * NOTE: This routine is just an optimization so it does not guarantee 3082 * that no dcache entries will exist at process exit time it 3083 * just makes it very unlikely that any will persist. 3084 */ 3085 3086 void proc_flush_task(struct task_struct *task) 3087 { 3088 int i; 3089 struct pid *pid, *tgid; 3090 struct upid *upid; 3091 3092 pid = task_pid(task); 3093 tgid = task_tgid(task); 3094 3095 for (i = 0; i <= pid->level; i++) { 3096 upid = &pid->numbers[i]; 3097 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 3098 tgid->numbers[i].nr); 3099 } 3100 } 3101 3102 static int proc_pid_instantiate(struct inode *dir, 3103 struct dentry * dentry, 3104 struct task_struct *task, const void *ptr) 3105 { 3106 struct inode *inode; 3107 3108 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); 3109 if (!inode) 3110 goto out; 3111 3112 inode->i_op = &proc_tgid_base_inode_operations; 3113 inode->i_fop = &proc_tgid_base_operations; 3114 inode->i_flags|=S_IMMUTABLE; 3115 3116 set_nlink(inode, nlink_tgid); 3117 3118 d_set_d_op(dentry, &pid_dentry_operations); 3119 3120 d_add(dentry, inode); 3121 /* Close the race of the process dying before we return the dentry */ 3122 if (pid_revalidate(dentry, 0)) 3123 return 0; 3124 out: 3125 return -ENOENT; 3126 } 3127 3128 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3129 { 3130 int result = -ENOENT; 3131 struct task_struct *task; 3132 unsigned tgid; 3133 struct pid_namespace *ns; 3134 3135 tgid = name_to_int(&dentry->d_name); 3136 if (tgid == ~0U) 3137 goto out; 3138 3139 ns = dentry->d_sb->s_fs_info; 3140 rcu_read_lock(); 3141 task = find_task_by_pid_ns(tgid, ns); 3142 if (task) 3143 get_task_struct(task); 3144 rcu_read_unlock(); 3145 if (!task) 3146 goto out; 3147 3148 result = proc_pid_instantiate(dir, dentry, task, NULL); 3149 put_task_struct(task); 3150 out: 3151 return ERR_PTR(result); 3152 } 3153 3154 /* 3155 * Find the first task with tgid >= tgid 3156 * 3157 */ 3158 struct tgid_iter { 3159 unsigned int tgid; 3160 struct task_struct *task; 3161 }; 3162 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 3163 { 3164 struct pid *pid; 3165 3166 if (iter.task) 3167 put_task_struct(iter.task); 3168 rcu_read_lock(); 3169 retry: 3170 iter.task = NULL; 3171 pid = find_ge_pid(iter.tgid, ns); 3172 if (pid) { 3173 iter.tgid = pid_nr_ns(pid, ns); 3174 iter.task = pid_task(pid, PIDTYPE_PID); 3175 /* What we to know is if the pid we have find is the 3176 * pid of a thread_group_leader. Testing for task 3177 * being a thread_group_leader is the obvious thing 3178 * todo but there is a window when it fails, due to 3179 * the pid transfer logic in de_thread. 3180 * 3181 * So we perform the straight forward test of seeing 3182 * if the pid we have found is the pid of a thread 3183 * group leader, and don't worry if the task we have 3184 * found doesn't happen to be a thread group leader. 3185 * As we don't care in the case of readdir. 3186 */ 3187 if (!iter.task || !has_group_leader_pid(iter.task)) { 3188 iter.tgid += 1; 3189 goto retry; 3190 } 3191 get_task_struct(iter.task); 3192 } 3193 rcu_read_unlock(); 3194 return iter; 3195 } 3196 3197 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2) 3198 3199 /* for the /proc/ directory itself, after non-process stuff has been done */ 3200 int proc_pid_readdir(struct file *file, struct dir_context *ctx) 3201 { 3202 struct tgid_iter iter; 3203 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info; 3204 loff_t pos = ctx->pos; 3205 3206 if (pos >= PID_MAX_LIMIT + TGID_OFFSET) 3207 return 0; 3208 3209 if (pos == TGID_OFFSET - 2) { 3210 struct inode *inode = d_inode(ns->proc_self); 3211 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK)) 3212 return 0; 3213 ctx->pos = pos = pos + 1; 3214 } 3215 if (pos == TGID_OFFSET - 1) { 3216 struct inode *inode = d_inode(ns->proc_thread_self); 3217 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK)) 3218 return 0; 3219 ctx->pos = pos = pos + 1; 3220 } 3221 iter.tgid = pos - TGID_OFFSET; 3222 iter.task = NULL; 3223 for (iter = next_tgid(ns, iter); 3224 iter.task; 3225 iter.tgid += 1, iter = next_tgid(ns, iter)) { 3226 char name[PROC_NUMBUF]; 3227 int len; 3228 3229 cond_resched(); 3230 if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE)) 3231 continue; 3232 3233 len = snprintf(name, sizeof(name), "%d", iter.tgid); 3234 ctx->pos = iter.tgid + TGID_OFFSET; 3235 if (!proc_fill_cache(file, ctx, name, len, 3236 proc_pid_instantiate, iter.task, NULL)) { 3237 put_task_struct(iter.task); 3238 return 0; 3239 } 3240 } 3241 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; 3242 return 0; 3243 } 3244 3245 /* 3246 * proc_tid_comm_permission is a special permission function exclusively 3247 * used for the node /proc/<pid>/task/<tid>/comm. 3248 * It bypasses generic permission checks in the case where a task of the same 3249 * task group attempts to access the node. 3250 * The rationale behind this is that glibc and bionic access this node for 3251 * cross thread naming (pthread_set/getname_np(!self)). However, if 3252 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0, 3253 * which locks out the cross thread naming implementation. 3254 * This function makes sure that the node is always accessible for members of 3255 * same thread group. 3256 */ 3257 static int proc_tid_comm_permission(struct inode *inode, int mask) 3258 { 3259 bool is_same_tgroup; 3260 struct task_struct *task; 3261 3262 task = get_proc_task(inode); 3263 if (!task) 3264 return -ESRCH; 3265 is_same_tgroup = same_thread_group(current, task); 3266 put_task_struct(task); 3267 3268 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) { 3269 /* This file (/proc/<pid>/task/<tid>/comm) can always be 3270 * read or written by the members of the corresponding 3271 * thread group. 3272 */ 3273 return 0; 3274 } 3275 3276 return generic_permission(inode, mask); 3277 } 3278 3279 static const struct inode_operations proc_tid_comm_inode_operations = { 3280 .permission = proc_tid_comm_permission, 3281 }; 3282 3283 /* 3284 * Tasks 3285 */ 3286 static const struct pid_entry tid_base_stuff[] = { 3287 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 3288 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 3289 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations), 3290 #ifdef CONFIG_NET 3291 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 3292 #endif 3293 REG("environ", S_IRUSR, proc_environ_operations), 3294 REG("auxv", S_IRUSR, proc_auxv_operations), 3295 ONE("status", S_IRUGO, proc_pid_status), 3296 ONE("personality", S_IRUSR, proc_pid_personality), 3297 ONE("limits", S_IRUGO, proc_pid_limits), 3298 #ifdef CONFIG_SCHED_DEBUG 3299 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 3300 #endif 3301 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR, 3302 &proc_tid_comm_inode_operations, 3303 &proc_pid_set_comm_operations, {}), 3304 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 3305 ONE("syscall", S_IRUSR, proc_pid_syscall), 3306 #endif 3307 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops), 3308 ONE("stat", S_IRUGO, proc_tid_stat), 3309 ONE("statm", S_IRUGO, proc_pid_statm), 3310 REG("maps", S_IRUGO, proc_tid_maps_operations), 3311 #ifdef CONFIG_PROC_CHILDREN 3312 REG("children", S_IRUGO, proc_tid_children_operations), 3313 #endif 3314 #ifdef CONFIG_NUMA 3315 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations), 3316 #endif 3317 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 3318 LNK("cwd", proc_cwd_link), 3319 LNK("root", proc_root_link), 3320 LNK("exe", proc_exe_link), 3321 REG("mounts", S_IRUGO, proc_mounts_operations), 3322 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 3323 #ifdef CONFIG_PROC_PAGE_MONITOR 3324 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 3325 REG("smaps", S_IRUGO, proc_tid_smaps_operations), 3326 REG("pagemap", S_IRUSR, proc_pagemap_operations), 3327 #endif 3328 #ifdef CONFIG_SECURITY 3329 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 3330 #endif 3331 #ifdef CONFIG_KALLSYMS 3332 ONE("wchan", S_IRUGO, proc_pid_wchan), 3333 #endif 3334 #ifdef CONFIG_STACKTRACE 3335 ONE("stack", S_IRUSR, proc_pid_stack), 3336 #endif 3337 #ifdef CONFIG_SCHED_INFO 3338 ONE("schedstat", S_IRUGO, proc_pid_schedstat), 3339 #endif 3340 #ifdef CONFIG_LATENCYTOP 3341 REG("latency", S_IRUGO, proc_lstats_operations), 3342 #endif 3343 #ifdef CONFIG_PROC_PID_CPUSET 3344 ONE("cpuset", S_IRUGO, proc_cpuset_show), 3345 #endif 3346 #ifdef CONFIG_CGROUPS 3347 ONE("cgroup", S_IRUGO, proc_cgroup_show), 3348 #endif 3349 ONE("oom_score", S_IRUGO, proc_oom_score), 3350 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), 3351 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations), 3352 #ifdef CONFIG_AUDITSYSCALL 3353 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 3354 REG("sessionid", S_IRUGO, proc_sessionid_operations), 3355 #endif 3356 #ifdef CONFIG_FAULT_INJECTION 3357 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 3358 REG("fail-nth", 0644, proc_fail_nth_operations), 3359 #endif 3360 #ifdef CONFIG_TASK_IO_ACCOUNTING 3361 ONE("io", S_IRUSR, proc_tid_io_accounting), 3362 #endif 3363 #ifdef CONFIG_HARDWALL 3364 ONE("hardwall", S_IRUGO, proc_pid_hardwall), 3365 #endif 3366 #ifdef CONFIG_USER_NS 3367 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations), 3368 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations), 3369 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations), 3370 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations), 3371 #endif 3372 #ifdef CONFIG_LIVEPATCH 3373 ONE("patch_state", S_IRUSR, proc_pid_patch_state), 3374 #endif 3375 }; 3376 3377 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) 3378 { 3379 return proc_pident_readdir(file, ctx, 3380 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3381 } 3382 3383 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 3384 { 3385 return proc_pident_lookup(dir, dentry, 3386 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3387 } 3388 3389 static const struct file_operations proc_tid_base_operations = { 3390 .read = generic_read_dir, 3391 .iterate_shared = proc_tid_base_readdir, 3392 .llseek = generic_file_llseek, 3393 }; 3394 3395 static const struct inode_operations proc_tid_base_inode_operations = { 3396 .lookup = proc_tid_base_lookup, 3397 .getattr = pid_getattr, 3398 .setattr = proc_setattr, 3399 }; 3400 3401 static int proc_task_instantiate(struct inode *dir, 3402 struct dentry *dentry, struct task_struct *task, const void *ptr) 3403 { 3404 struct inode *inode; 3405 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); 3406 3407 if (!inode) 3408 goto out; 3409 inode->i_op = &proc_tid_base_inode_operations; 3410 inode->i_fop = &proc_tid_base_operations; 3411 inode->i_flags|=S_IMMUTABLE; 3412 3413 set_nlink(inode, nlink_tid); 3414 3415 d_set_d_op(dentry, &pid_dentry_operations); 3416 3417 d_add(dentry, inode); 3418 /* Close the race of the process dying before we return the dentry */ 3419 if (pid_revalidate(dentry, 0)) 3420 return 0; 3421 out: 3422 return -ENOENT; 3423 } 3424 3425 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) 3426 { 3427 int result = -ENOENT; 3428 struct task_struct *task; 3429 struct task_struct *leader = get_proc_task(dir); 3430 unsigned tid; 3431 struct pid_namespace *ns; 3432 3433 if (!leader) 3434 goto out_no_task; 3435 3436 tid = name_to_int(&dentry->d_name); 3437 if (tid == ~0U) 3438 goto out; 3439 3440 ns = dentry->d_sb->s_fs_info; 3441 rcu_read_lock(); 3442 task = find_task_by_pid_ns(tid, ns); 3443 if (task) 3444 get_task_struct(task); 3445 rcu_read_unlock(); 3446 if (!task) 3447 goto out; 3448 if (!same_thread_group(leader, task)) 3449 goto out_drop_task; 3450 3451 result = proc_task_instantiate(dir, dentry, task, NULL); 3452 out_drop_task: 3453 put_task_struct(task); 3454 out: 3455 put_task_struct(leader); 3456 out_no_task: 3457 return ERR_PTR(result); 3458 } 3459 3460 /* 3461 * Find the first tid of a thread group to return to user space. 3462 * 3463 * Usually this is just the thread group leader, but if the users 3464 * buffer was too small or there was a seek into the middle of the 3465 * directory we have more work todo. 3466 * 3467 * In the case of a short read we start with find_task_by_pid. 3468 * 3469 * In the case of a seek we start with the leader and walk nr 3470 * threads past it. 3471 */ 3472 static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos, 3473 struct pid_namespace *ns) 3474 { 3475 struct task_struct *pos, *task; 3476 unsigned long nr = f_pos; 3477 3478 if (nr != f_pos) /* 32bit overflow? */ 3479 return NULL; 3480 3481 rcu_read_lock(); 3482 task = pid_task(pid, PIDTYPE_PID); 3483 if (!task) 3484 goto fail; 3485 3486 /* Attempt to start with the tid of a thread */ 3487 if (tid && nr) { 3488 pos = find_task_by_pid_ns(tid, ns); 3489 if (pos && same_thread_group(pos, task)) 3490 goto found; 3491 } 3492 3493 /* If nr exceeds the number of threads there is nothing todo */ 3494 if (nr >= get_nr_threads(task)) 3495 goto fail; 3496 3497 /* If we haven't found our starting place yet start 3498 * with the leader and walk nr threads forward. 3499 */ 3500 pos = task = task->group_leader; 3501 do { 3502 if (!nr--) 3503 goto found; 3504 } while_each_thread(task, pos); 3505 fail: 3506 pos = NULL; 3507 goto out; 3508 found: 3509 get_task_struct(pos); 3510 out: 3511 rcu_read_unlock(); 3512 return pos; 3513 } 3514 3515 /* 3516 * Find the next thread in the thread list. 3517 * Return NULL if there is an error or no next thread. 3518 * 3519 * The reference to the input task_struct is released. 3520 */ 3521 static struct task_struct *next_tid(struct task_struct *start) 3522 { 3523 struct task_struct *pos = NULL; 3524 rcu_read_lock(); 3525 if (pid_alive(start)) { 3526 pos = next_thread(start); 3527 if (thread_group_leader(pos)) 3528 pos = NULL; 3529 else 3530 get_task_struct(pos); 3531 } 3532 rcu_read_unlock(); 3533 put_task_struct(start); 3534 return pos; 3535 } 3536 3537 /* for the /proc/TGID/task/ directories */ 3538 static int proc_task_readdir(struct file *file, struct dir_context *ctx) 3539 { 3540 struct inode *inode = file_inode(file); 3541 struct task_struct *task; 3542 struct pid_namespace *ns; 3543 int tid; 3544 3545 if (proc_inode_is_dead(inode)) 3546 return -ENOENT; 3547 3548 if (!dir_emit_dots(file, ctx)) 3549 return 0; 3550 3551 /* f_version caches the tgid value that the last readdir call couldn't 3552 * return. lseek aka telldir automagically resets f_version to 0. 3553 */ 3554 ns = inode->i_sb->s_fs_info; 3555 tid = (int)file->f_version; 3556 file->f_version = 0; 3557 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns); 3558 task; 3559 task = next_tid(task), ctx->pos++) { 3560 char name[PROC_NUMBUF]; 3561 int len; 3562 tid = task_pid_nr_ns(task, ns); 3563 len = snprintf(name, sizeof(name), "%d", tid); 3564 if (!proc_fill_cache(file, ctx, name, len, 3565 proc_task_instantiate, task, NULL)) { 3566 /* returning this tgid failed, save it as the first 3567 * pid for the next readir call */ 3568 file->f_version = (u64)tid; 3569 put_task_struct(task); 3570 break; 3571 } 3572 } 3573 3574 return 0; 3575 } 3576 3577 static int proc_task_getattr(const struct path *path, struct kstat *stat, 3578 u32 request_mask, unsigned int query_flags) 3579 { 3580 struct inode *inode = d_inode(path->dentry); 3581 struct task_struct *p = get_proc_task(inode); 3582 generic_fillattr(inode, stat); 3583 3584 if (p) { 3585 stat->nlink += get_nr_threads(p); 3586 put_task_struct(p); 3587 } 3588 3589 return 0; 3590 } 3591 3592 static const struct inode_operations proc_task_inode_operations = { 3593 .lookup = proc_task_lookup, 3594 .getattr = proc_task_getattr, 3595 .setattr = proc_setattr, 3596 .permission = proc_pid_permission, 3597 }; 3598 3599 static const struct file_operations proc_task_operations = { 3600 .read = generic_read_dir, 3601 .iterate_shared = proc_task_readdir, 3602 .llseek = generic_file_llseek, 3603 }; 3604 3605 void __init set_proc_pid_nlink(void) 3606 { 3607 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 3608 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 3609 } 3610