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