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