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/rcupdate.h> 67 #include <linux/kallsyms.h> 68 #include <linux/stacktrace.h> 69 #include <linux/resource.h> 70 #include <linux/module.h> 71 #include <linux/mount.h> 72 #include <linux/security.h> 73 #include <linux/ptrace.h> 74 #include <linux/tracehook.h> 75 #include <linux/cgroup.h> 76 #include <linux/cpuset.h> 77 #include <linux/audit.h> 78 #include <linux/poll.h> 79 #include <linux/nsproxy.h> 80 #include <linux/oom.h> 81 #include <linux/elf.h> 82 #include <linux/pid_namespace.h> 83 #include <linux/fs_struct.h> 84 #include <linux/slab.h> 85 #include "internal.h" 86 87 /* NOTE: 88 * Implementing inode permission operations in /proc is almost 89 * certainly an error. Permission checks need to happen during 90 * each system call not at open time. The reason is that most of 91 * what we wish to check for permissions in /proc varies at runtime. 92 * 93 * The classic example of a problem is opening file descriptors 94 * in /proc for a task before it execs a suid executable. 95 */ 96 97 struct pid_entry { 98 char *name; 99 int len; 100 mode_t mode; 101 const struct inode_operations *iop; 102 const struct file_operations *fop; 103 union proc_op op; 104 }; 105 106 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 107 .name = (NAME), \ 108 .len = sizeof(NAME) - 1, \ 109 .mode = MODE, \ 110 .iop = IOP, \ 111 .fop = FOP, \ 112 .op = OP, \ 113 } 114 115 #define DIR(NAME, MODE, iops, fops) \ 116 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) 117 #define LNK(NAME, get_link) \ 118 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 119 &proc_pid_link_inode_operations, NULL, \ 120 { .proc_get_link = get_link } ) 121 #define REG(NAME, MODE, fops) \ 122 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) 123 #define INF(NAME, MODE, read) \ 124 NOD(NAME, (S_IFREG|(MODE)), \ 125 NULL, &proc_info_file_operations, \ 126 { .proc_read = read } ) 127 #define ONE(NAME, MODE, show) \ 128 NOD(NAME, (S_IFREG|(MODE)), \ 129 NULL, &proc_single_file_operations, \ 130 { .proc_show = show } ) 131 132 /* 133 * Count the number of hardlinks for the pid_entry table, excluding the . 134 * and .. links. 135 */ 136 static unsigned int pid_entry_count_dirs(const struct pid_entry *entries, 137 unsigned int n) 138 { 139 unsigned int i; 140 unsigned int count; 141 142 count = 0; 143 for (i = 0; i < n; ++i) { 144 if (S_ISDIR(entries[i].mode)) 145 ++count; 146 } 147 148 return count; 149 } 150 151 static int get_fs_path(struct task_struct *task, struct path *path, bool root) 152 { 153 struct fs_struct *fs; 154 int result = -ENOENT; 155 156 task_lock(task); 157 fs = task->fs; 158 if (fs) { 159 read_lock(&fs->lock); 160 *path = root ? fs->root : fs->pwd; 161 path_get(path); 162 read_unlock(&fs->lock); 163 result = 0; 164 } 165 task_unlock(task); 166 return result; 167 } 168 169 static int proc_cwd_link(struct inode *inode, struct path *path) 170 { 171 struct task_struct *task = get_proc_task(inode); 172 int result = -ENOENT; 173 174 if (task) { 175 result = get_fs_path(task, path, 0); 176 put_task_struct(task); 177 } 178 return result; 179 } 180 181 static int proc_root_link(struct inode *inode, struct path *path) 182 { 183 struct task_struct *task = get_proc_task(inode); 184 int result = -ENOENT; 185 186 if (task) { 187 result = get_fs_path(task, path, 1); 188 put_task_struct(task); 189 } 190 return result; 191 } 192 193 /* 194 * Return zero if current may access user memory in @task, -error if not. 195 */ 196 static int check_mem_permission(struct task_struct *task) 197 { 198 /* 199 * A task can always look at itself, in case it chooses 200 * to use system calls instead of load instructions. 201 */ 202 if (task == current) 203 return 0; 204 205 /* 206 * If current is actively ptrace'ing, and would also be 207 * permitted to freshly attach with ptrace now, permit it. 208 */ 209 if (task_is_stopped_or_traced(task)) { 210 int match; 211 rcu_read_lock(); 212 match = (tracehook_tracer_task(task) == current); 213 rcu_read_unlock(); 214 if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH)) 215 return 0; 216 } 217 218 /* 219 * Noone else is allowed. 220 */ 221 return -EPERM; 222 } 223 224 struct mm_struct *mm_for_maps(struct task_struct *task) 225 { 226 struct mm_struct *mm; 227 228 if (mutex_lock_killable(&task->cred_guard_mutex)) 229 return NULL; 230 231 mm = get_task_mm(task); 232 if (mm && mm != current->mm && 233 !ptrace_may_access(task, PTRACE_MODE_READ)) { 234 mmput(mm); 235 mm = NULL; 236 } 237 mutex_unlock(&task->cred_guard_mutex); 238 239 return mm; 240 } 241 242 static int proc_pid_cmdline(struct task_struct *task, char * buffer) 243 { 244 int res = 0; 245 unsigned int len; 246 struct mm_struct *mm = get_task_mm(task); 247 if (!mm) 248 goto out; 249 if (!mm->arg_end) 250 goto out_mm; /* Shh! No looking before we're done */ 251 252 len = mm->arg_end - mm->arg_start; 253 254 if (len > PAGE_SIZE) 255 len = PAGE_SIZE; 256 257 res = access_process_vm(task, mm->arg_start, buffer, len, 0); 258 259 // If the nul at the end of args has been overwritten, then 260 // assume application is using setproctitle(3). 261 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { 262 len = strnlen(buffer, res); 263 if (len < res) { 264 res = len; 265 } else { 266 len = mm->env_end - mm->env_start; 267 if (len > PAGE_SIZE - res) 268 len = PAGE_SIZE - res; 269 res += access_process_vm(task, mm->env_start, buffer+res, len, 0); 270 res = strnlen(buffer, res); 271 } 272 } 273 out_mm: 274 mmput(mm); 275 out: 276 return res; 277 } 278 279 static int proc_pid_auxv(struct task_struct *task, char *buffer) 280 { 281 int res = 0; 282 struct mm_struct *mm = get_task_mm(task); 283 if (mm) { 284 unsigned int nwords = 0; 285 do { 286 nwords += 2; 287 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 288 res = nwords * sizeof(mm->saved_auxv[0]); 289 if (res > PAGE_SIZE) 290 res = PAGE_SIZE; 291 memcpy(buffer, mm->saved_auxv, res); 292 mmput(mm); 293 } 294 return res; 295 } 296 297 298 #ifdef CONFIG_KALLSYMS 299 /* 300 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 301 * Returns the resolved symbol. If that fails, simply return the address. 302 */ 303 static int proc_pid_wchan(struct task_struct *task, char *buffer) 304 { 305 unsigned long wchan; 306 char symname[KSYM_NAME_LEN]; 307 308 wchan = get_wchan(task); 309 310 if (lookup_symbol_name(wchan, symname) < 0) 311 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 312 return 0; 313 else 314 return sprintf(buffer, "%lu", wchan); 315 else 316 return sprintf(buffer, "%s", symname); 317 } 318 #endif /* CONFIG_KALLSYMS */ 319 320 #ifdef CONFIG_STACKTRACE 321 322 #define MAX_STACK_TRACE_DEPTH 64 323 324 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, 325 struct pid *pid, struct task_struct *task) 326 { 327 struct stack_trace trace; 328 unsigned long *entries; 329 int i; 330 331 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL); 332 if (!entries) 333 return -ENOMEM; 334 335 trace.nr_entries = 0; 336 trace.max_entries = MAX_STACK_TRACE_DEPTH; 337 trace.entries = entries; 338 trace.skip = 0; 339 save_stack_trace_tsk(task, &trace); 340 341 for (i = 0; i < trace.nr_entries; i++) { 342 seq_printf(m, "[<%p>] %pS\n", 343 (void *)entries[i], (void *)entries[i]); 344 } 345 kfree(entries); 346 347 return 0; 348 } 349 #endif 350 351 #ifdef CONFIG_SCHEDSTATS 352 /* 353 * Provides /proc/PID/schedstat 354 */ 355 static int proc_pid_schedstat(struct task_struct *task, char *buffer) 356 { 357 return sprintf(buffer, "%llu %llu %lu\n", 358 (unsigned long long)task->se.sum_exec_runtime, 359 (unsigned long long)task->sched_info.run_delay, 360 task->sched_info.pcount); 361 } 362 #endif 363 364 #ifdef CONFIG_LATENCYTOP 365 static int lstats_show_proc(struct seq_file *m, void *v) 366 { 367 int i; 368 struct inode *inode = m->private; 369 struct task_struct *task = get_proc_task(inode); 370 371 if (!task) 372 return -ESRCH; 373 seq_puts(m, "Latency Top version : v0.1\n"); 374 for (i = 0; i < 32; i++) { 375 if (task->latency_record[i].backtrace[0]) { 376 int q; 377 seq_printf(m, "%i %li %li ", 378 task->latency_record[i].count, 379 task->latency_record[i].time, 380 task->latency_record[i].max); 381 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 382 char sym[KSYM_SYMBOL_LEN]; 383 char *c; 384 if (!task->latency_record[i].backtrace[q]) 385 break; 386 if (task->latency_record[i].backtrace[q] == ULONG_MAX) 387 break; 388 sprint_symbol(sym, task->latency_record[i].backtrace[q]); 389 c = strchr(sym, '+'); 390 if (c) 391 *c = 0; 392 seq_printf(m, "%s ", sym); 393 } 394 seq_printf(m, "\n"); 395 } 396 397 } 398 put_task_struct(task); 399 return 0; 400 } 401 402 static int lstats_open(struct inode *inode, struct file *file) 403 { 404 return single_open(file, lstats_show_proc, inode); 405 } 406 407 static ssize_t lstats_write(struct file *file, const char __user *buf, 408 size_t count, loff_t *offs) 409 { 410 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 411 412 if (!task) 413 return -ESRCH; 414 clear_all_latency_tracing(task); 415 put_task_struct(task); 416 417 return count; 418 } 419 420 static const struct file_operations proc_lstats_operations = { 421 .open = lstats_open, 422 .read = seq_read, 423 .write = lstats_write, 424 .llseek = seq_lseek, 425 .release = single_release, 426 }; 427 428 #endif 429 430 /* The badness from the OOM killer */ 431 unsigned long badness(struct task_struct *p, unsigned long uptime); 432 static int proc_oom_score(struct task_struct *task, char *buffer) 433 { 434 unsigned long points = 0; 435 struct timespec uptime; 436 437 do_posix_clock_monotonic_gettime(&uptime); 438 read_lock(&tasklist_lock); 439 if (pid_alive(task)) 440 points = badness(task, uptime.tv_sec); 441 read_unlock(&tasklist_lock); 442 return sprintf(buffer, "%lu\n", points); 443 } 444 445 struct limit_names { 446 char *name; 447 char *unit; 448 }; 449 450 static const struct limit_names lnames[RLIM_NLIMITS] = { 451 [RLIMIT_CPU] = {"Max cpu time", "seconds"}, 452 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 453 [RLIMIT_DATA] = {"Max data size", "bytes"}, 454 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 455 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 456 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 457 [RLIMIT_NPROC] = {"Max processes", "processes"}, 458 [RLIMIT_NOFILE] = {"Max open files", "files"}, 459 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 460 [RLIMIT_AS] = {"Max address space", "bytes"}, 461 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 462 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 463 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 464 [RLIMIT_NICE] = {"Max nice priority", NULL}, 465 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 466 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 467 }; 468 469 /* Display limits for a process */ 470 static int proc_pid_limits(struct task_struct *task, char *buffer) 471 { 472 unsigned int i; 473 int count = 0; 474 unsigned long flags; 475 char *bufptr = buffer; 476 477 struct rlimit rlim[RLIM_NLIMITS]; 478 479 if (!lock_task_sighand(task, &flags)) 480 return 0; 481 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 482 unlock_task_sighand(task, &flags); 483 484 /* 485 * print the file header 486 */ 487 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n", 488 "Limit", "Soft Limit", "Hard Limit", "Units"); 489 490 for (i = 0; i < RLIM_NLIMITS; i++) { 491 if (rlim[i].rlim_cur == RLIM_INFINITY) 492 count += sprintf(&bufptr[count], "%-25s %-20s ", 493 lnames[i].name, "unlimited"); 494 else 495 count += sprintf(&bufptr[count], "%-25s %-20lu ", 496 lnames[i].name, rlim[i].rlim_cur); 497 498 if (rlim[i].rlim_max == RLIM_INFINITY) 499 count += sprintf(&bufptr[count], "%-20s ", "unlimited"); 500 else 501 count += sprintf(&bufptr[count], "%-20lu ", 502 rlim[i].rlim_max); 503 504 if (lnames[i].unit) 505 count += sprintf(&bufptr[count], "%-10s\n", 506 lnames[i].unit); 507 else 508 count += sprintf(&bufptr[count], "\n"); 509 } 510 511 return count; 512 } 513 514 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 515 static int proc_pid_syscall(struct task_struct *task, char *buffer) 516 { 517 long nr; 518 unsigned long args[6], sp, pc; 519 520 if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) 521 return sprintf(buffer, "running\n"); 522 523 if (nr < 0) 524 return sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc); 525 526 return sprintf(buffer, 527 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 528 nr, 529 args[0], args[1], args[2], args[3], args[4], args[5], 530 sp, pc); 531 } 532 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ 533 534 /************************************************************************/ 535 /* Here the fs part begins */ 536 /************************************************************************/ 537 538 /* permission checks */ 539 static int proc_fd_access_allowed(struct inode *inode) 540 { 541 struct task_struct *task; 542 int allowed = 0; 543 /* Allow access to a task's file descriptors if it is us or we 544 * may use ptrace attach to the process and find out that 545 * information. 546 */ 547 task = get_proc_task(inode); 548 if (task) { 549 allowed = ptrace_may_access(task, PTRACE_MODE_READ); 550 put_task_struct(task); 551 } 552 return allowed; 553 } 554 555 static int proc_setattr(struct dentry *dentry, struct iattr *attr) 556 { 557 int error; 558 struct inode *inode = dentry->d_inode; 559 560 if (attr->ia_valid & ATTR_MODE) 561 return -EPERM; 562 563 error = inode_change_ok(inode, attr); 564 if (!error) 565 error = inode_setattr(inode, attr); 566 return error; 567 } 568 569 static const struct inode_operations proc_def_inode_operations = { 570 .setattr = proc_setattr, 571 }; 572 573 static int mounts_open_common(struct inode *inode, struct file *file, 574 const struct seq_operations *op) 575 { 576 struct task_struct *task = get_proc_task(inode); 577 struct nsproxy *nsp; 578 struct mnt_namespace *ns = NULL; 579 struct path root; 580 struct proc_mounts *p; 581 int ret = -EINVAL; 582 583 if (task) { 584 rcu_read_lock(); 585 nsp = task_nsproxy(task); 586 if (nsp) { 587 ns = nsp->mnt_ns; 588 if (ns) 589 get_mnt_ns(ns); 590 } 591 rcu_read_unlock(); 592 if (ns && get_fs_path(task, &root, 1) == 0) 593 ret = 0; 594 put_task_struct(task); 595 } 596 597 if (!ns) 598 goto err; 599 if (ret) 600 goto err_put_ns; 601 602 ret = -ENOMEM; 603 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); 604 if (!p) 605 goto err_put_path; 606 607 file->private_data = &p->m; 608 ret = seq_open(file, op); 609 if (ret) 610 goto err_free; 611 612 p->m.private = p; 613 p->ns = ns; 614 p->root = root; 615 p->event = ns->event; 616 617 return 0; 618 619 err_free: 620 kfree(p); 621 err_put_path: 622 path_put(&root); 623 err_put_ns: 624 put_mnt_ns(ns); 625 err: 626 return ret; 627 } 628 629 static int mounts_release(struct inode *inode, struct file *file) 630 { 631 struct proc_mounts *p = file->private_data; 632 path_put(&p->root); 633 put_mnt_ns(p->ns); 634 return seq_release(inode, file); 635 } 636 637 static unsigned mounts_poll(struct file *file, poll_table *wait) 638 { 639 struct proc_mounts *p = file->private_data; 640 unsigned res = POLLIN | POLLRDNORM; 641 642 poll_wait(file, &p->ns->poll, wait); 643 if (mnt_had_events(p)) 644 res |= POLLERR | POLLPRI; 645 646 return res; 647 } 648 649 static int mounts_open(struct inode *inode, struct file *file) 650 { 651 return mounts_open_common(inode, file, &mounts_op); 652 } 653 654 static const struct file_operations proc_mounts_operations = { 655 .open = mounts_open, 656 .read = seq_read, 657 .llseek = seq_lseek, 658 .release = mounts_release, 659 .poll = mounts_poll, 660 }; 661 662 static int mountinfo_open(struct inode *inode, struct file *file) 663 { 664 return mounts_open_common(inode, file, &mountinfo_op); 665 } 666 667 static const struct file_operations proc_mountinfo_operations = { 668 .open = mountinfo_open, 669 .read = seq_read, 670 .llseek = seq_lseek, 671 .release = mounts_release, 672 .poll = mounts_poll, 673 }; 674 675 static int mountstats_open(struct inode *inode, struct file *file) 676 { 677 return mounts_open_common(inode, file, &mountstats_op); 678 } 679 680 static const struct file_operations proc_mountstats_operations = { 681 .open = mountstats_open, 682 .read = seq_read, 683 .llseek = seq_lseek, 684 .release = mounts_release, 685 }; 686 687 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 688 689 static ssize_t proc_info_read(struct file * file, char __user * buf, 690 size_t count, loff_t *ppos) 691 { 692 struct inode * inode = file->f_path.dentry->d_inode; 693 unsigned long page; 694 ssize_t length; 695 struct task_struct *task = get_proc_task(inode); 696 697 length = -ESRCH; 698 if (!task) 699 goto out_no_task; 700 701 if (count > PROC_BLOCK_SIZE) 702 count = PROC_BLOCK_SIZE; 703 704 length = -ENOMEM; 705 if (!(page = __get_free_page(GFP_TEMPORARY))) 706 goto out; 707 708 length = PROC_I(inode)->op.proc_read(task, (char*)page); 709 710 if (length >= 0) 711 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 712 free_page(page); 713 out: 714 put_task_struct(task); 715 out_no_task: 716 return length; 717 } 718 719 static const struct file_operations proc_info_file_operations = { 720 .read = proc_info_read, 721 .llseek = generic_file_llseek, 722 }; 723 724 static int proc_single_show(struct seq_file *m, void *v) 725 { 726 struct inode *inode = m->private; 727 struct pid_namespace *ns; 728 struct pid *pid; 729 struct task_struct *task; 730 int ret; 731 732 ns = inode->i_sb->s_fs_info; 733 pid = proc_pid(inode); 734 task = get_pid_task(pid, PIDTYPE_PID); 735 if (!task) 736 return -ESRCH; 737 738 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 739 740 put_task_struct(task); 741 return ret; 742 } 743 744 static int proc_single_open(struct inode *inode, struct file *filp) 745 { 746 int ret; 747 ret = single_open(filp, proc_single_show, NULL); 748 if (!ret) { 749 struct seq_file *m = filp->private_data; 750 751 m->private = inode; 752 } 753 return ret; 754 } 755 756 static const struct file_operations proc_single_file_operations = { 757 .open = proc_single_open, 758 .read = seq_read, 759 .llseek = seq_lseek, 760 .release = single_release, 761 }; 762 763 static int mem_open(struct inode* inode, struct file* file) 764 { 765 file->private_data = (void*)((long)current->self_exec_id); 766 return 0; 767 } 768 769 static ssize_t mem_read(struct file * file, char __user * buf, 770 size_t count, loff_t *ppos) 771 { 772 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 773 char *page; 774 unsigned long src = *ppos; 775 int ret = -ESRCH; 776 struct mm_struct *mm; 777 778 if (!task) 779 goto out_no_task; 780 781 if (check_mem_permission(task)) 782 goto out; 783 784 ret = -ENOMEM; 785 page = (char *)__get_free_page(GFP_TEMPORARY); 786 if (!page) 787 goto out; 788 789 ret = 0; 790 791 mm = get_task_mm(task); 792 if (!mm) 793 goto out_free; 794 795 ret = -EIO; 796 797 if (file->private_data != (void*)((long)current->self_exec_id)) 798 goto out_put; 799 800 ret = 0; 801 802 while (count > 0) { 803 int this_len, retval; 804 805 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 806 retval = access_process_vm(task, src, page, this_len, 0); 807 if (!retval || check_mem_permission(task)) { 808 if (!ret) 809 ret = -EIO; 810 break; 811 } 812 813 if (copy_to_user(buf, page, retval)) { 814 ret = -EFAULT; 815 break; 816 } 817 818 ret += retval; 819 src += retval; 820 buf += retval; 821 count -= retval; 822 } 823 *ppos = src; 824 825 out_put: 826 mmput(mm); 827 out_free: 828 free_page((unsigned long) page); 829 out: 830 put_task_struct(task); 831 out_no_task: 832 return ret; 833 } 834 835 #define mem_write NULL 836 837 #ifndef mem_write 838 /* This is a security hazard */ 839 static ssize_t mem_write(struct file * file, const char __user *buf, 840 size_t count, loff_t *ppos) 841 { 842 int copied; 843 char *page; 844 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 845 unsigned long dst = *ppos; 846 847 copied = -ESRCH; 848 if (!task) 849 goto out_no_task; 850 851 if (check_mem_permission(task)) 852 goto out; 853 854 copied = -ENOMEM; 855 page = (char *)__get_free_page(GFP_TEMPORARY); 856 if (!page) 857 goto out; 858 859 copied = 0; 860 while (count > 0) { 861 int this_len, retval; 862 863 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 864 if (copy_from_user(page, buf, this_len)) { 865 copied = -EFAULT; 866 break; 867 } 868 retval = access_process_vm(task, dst, page, this_len, 1); 869 if (!retval) { 870 if (!copied) 871 copied = -EIO; 872 break; 873 } 874 copied += retval; 875 buf += retval; 876 dst += retval; 877 count -= retval; 878 } 879 *ppos = dst; 880 free_page((unsigned long) page); 881 out: 882 put_task_struct(task); 883 out_no_task: 884 return copied; 885 } 886 #endif 887 888 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 889 { 890 switch (orig) { 891 case 0: 892 file->f_pos = offset; 893 break; 894 case 1: 895 file->f_pos += offset; 896 break; 897 default: 898 return -EINVAL; 899 } 900 force_successful_syscall_return(); 901 return file->f_pos; 902 } 903 904 static const struct file_operations proc_mem_operations = { 905 .llseek = mem_lseek, 906 .read = mem_read, 907 .write = mem_write, 908 .open = mem_open, 909 }; 910 911 static ssize_t environ_read(struct file *file, char __user *buf, 912 size_t count, loff_t *ppos) 913 { 914 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 915 char *page; 916 unsigned long src = *ppos; 917 int ret = -ESRCH; 918 struct mm_struct *mm; 919 920 if (!task) 921 goto out_no_task; 922 923 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 924 goto out; 925 926 ret = -ENOMEM; 927 page = (char *)__get_free_page(GFP_TEMPORARY); 928 if (!page) 929 goto out; 930 931 ret = 0; 932 933 mm = get_task_mm(task); 934 if (!mm) 935 goto out_free; 936 937 while (count > 0) { 938 int this_len, retval, max_len; 939 940 this_len = mm->env_end - (mm->env_start + src); 941 942 if (this_len <= 0) 943 break; 944 945 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 946 this_len = (this_len > max_len) ? max_len : this_len; 947 948 retval = access_process_vm(task, (mm->env_start + src), 949 page, this_len, 0); 950 951 if (retval <= 0) { 952 ret = retval; 953 break; 954 } 955 956 if (copy_to_user(buf, page, retval)) { 957 ret = -EFAULT; 958 break; 959 } 960 961 ret += retval; 962 src += retval; 963 buf += retval; 964 count -= retval; 965 } 966 *ppos = src; 967 968 mmput(mm); 969 out_free: 970 free_page((unsigned long) page); 971 out: 972 put_task_struct(task); 973 out_no_task: 974 return ret; 975 } 976 977 static const struct file_operations proc_environ_operations = { 978 .read = environ_read, 979 .llseek = generic_file_llseek, 980 }; 981 982 static ssize_t oom_adjust_read(struct file *file, char __user *buf, 983 size_t count, loff_t *ppos) 984 { 985 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 986 char buffer[PROC_NUMBUF]; 987 size_t len; 988 int oom_adjust = OOM_DISABLE; 989 unsigned long flags; 990 991 if (!task) 992 return -ESRCH; 993 994 if (lock_task_sighand(task, &flags)) { 995 oom_adjust = task->signal->oom_adj; 996 unlock_task_sighand(task, &flags); 997 } 998 999 put_task_struct(task); 1000 1001 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust); 1002 1003 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1004 } 1005 1006 static ssize_t oom_adjust_write(struct file *file, const char __user *buf, 1007 size_t count, loff_t *ppos) 1008 { 1009 struct task_struct *task; 1010 char buffer[PROC_NUMBUF]; 1011 long oom_adjust; 1012 unsigned long flags; 1013 int err; 1014 1015 memset(buffer, 0, sizeof(buffer)); 1016 if (count > sizeof(buffer) - 1) 1017 count = sizeof(buffer) - 1; 1018 if (copy_from_user(buffer, buf, count)) 1019 return -EFAULT; 1020 1021 err = strict_strtol(strstrip(buffer), 0, &oom_adjust); 1022 if (err) 1023 return -EINVAL; 1024 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) && 1025 oom_adjust != OOM_DISABLE) 1026 return -EINVAL; 1027 1028 task = get_proc_task(file->f_path.dentry->d_inode); 1029 if (!task) 1030 return -ESRCH; 1031 if (!lock_task_sighand(task, &flags)) { 1032 put_task_struct(task); 1033 return -ESRCH; 1034 } 1035 1036 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) { 1037 unlock_task_sighand(task, &flags); 1038 put_task_struct(task); 1039 return -EACCES; 1040 } 1041 1042 task->signal->oom_adj = oom_adjust; 1043 1044 unlock_task_sighand(task, &flags); 1045 put_task_struct(task); 1046 1047 return count; 1048 } 1049 1050 static const struct file_operations proc_oom_adjust_operations = { 1051 .read = oom_adjust_read, 1052 .write = oom_adjust_write, 1053 .llseek = generic_file_llseek, 1054 }; 1055 1056 #ifdef CONFIG_AUDITSYSCALL 1057 #define TMPBUFLEN 21 1058 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 1059 size_t count, loff_t *ppos) 1060 { 1061 struct inode * inode = file->f_path.dentry->d_inode; 1062 struct task_struct *task = get_proc_task(inode); 1063 ssize_t length; 1064 char tmpbuf[TMPBUFLEN]; 1065 1066 if (!task) 1067 return -ESRCH; 1068 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1069 audit_get_loginuid(task)); 1070 put_task_struct(task); 1071 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1072 } 1073 1074 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1075 size_t count, loff_t *ppos) 1076 { 1077 struct inode * inode = file->f_path.dentry->d_inode; 1078 char *page, *tmp; 1079 ssize_t length; 1080 uid_t loginuid; 1081 1082 if (!capable(CAP_AUDIT_CONTROL)) 1083 return -EPERM; 1084 1085 rcu_read_lock(); 1086 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) { 1087 rcu_read_unlock(); 1088 return -EPERM; 1089 } 1090 rcu_read_unlock(); 1091 1092 if (count >= PAGE_SIZE) 1093 count = PAGE_SIZE - 1; 1094 1095 if (*ppos != 0) { 1096 /* No partial writes. */ 1097 return -EINVAL; 1098 } 1099 page = (char*)__get_free_page(GFP_TEMPORARY); 1100 if (!page) 1101 return -ENOMEM; 1102 length = -EFAULT; 1103 if (copy_from_user(page, buf, count)) 1104 goto out_free_page; 1105 1106 page[count] = '\0'; 1107 loginuid = simple_strtoul(page, &tmp, 10); 1108 if (tmp == page) { 1109 length = -EINVAL; 1110 goto out_free_page; 1111 1112 } 1113 length = audit_set_loginuid(current, loginuid); 1114 if (likely(length == 0)) 1115 length = count; 1116 1117 out_free_page: 1118 free_page((unsigned long) page); 1119 return length; 1120 } 1121 1122 static const struct file_operations proc_loginuid_operations = { 1123 .read = proc_loginuid_read, 1124 .write = proc_loginuid_write, 1125 .llseek = generic_file_llseek, 1126 }; 1127 1128 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1129 size_t count, loff_t *ppos) 1130 { 1131 struct inode * inode = file->f_path.dentry->d_inode; 1132 struct task_struct *task = get_proc_task(inode); 1133 ssize_t length; 1134 char tmpbuf[TMPBUFLEN]; 1135 1136 if (!task) 1137 return -ESRCH; 1138 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1139 audit_get_sessionid(task)); 1140 put_task_struct(task); 1141 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1142 } 1143 1144 static const struct file_operations proc_sessionid_operations = { 1145 .read = proc_sessionid_read, 1146 .llseek = generic_file_llseek, 1147 }; 1148 #endif 1149 1150 #ifdef CONFIG_FAULT_INJECTION 1151 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1152 size_t count, loff_t *ppos) 1153 { 1154 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 1155 char buffer[PROC_NUMBUF]; 1156 size_t len; 1157 int make_it_fail; 1158 1159 if (!task) 1160 return -ESRCH; 1161 make_it_fail = task->make_it_fail; 1162 put_task_struct(task); 1163 1164 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1165 1166 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1167 } 1168 1169 static ssize_t proc_fault_inject_write(struct file * file, 1170 const char __user * buf, size_t count, loff_t *ppos) 1171 { 1172 struct task_struct *task; 1173 char buffer[PROC_NUMBUF], *end; 1174 int make_it_fail; 1175 1176 if (!capable(CAP_SYS_RESOURCE)) 1177 return -EPERM; 1178 memset(buffer, 0, sizeof(buffer)); 1179 if (count > sizeof(buffer) - 1) 1180 count = sizeof(buffer) - 1; 1181 if (copy_from_user(buffer, buf, count)) 1182 return -EFAULT; 1183 make_it_fail = simple_strtol(strstrip(buffer), &end, 0); 1184 if (*end) 1185 return -EINVAL; 1186 task = get_proc_task(file->f_dentry->d_inode); 1187 if (!task) 1188 return -ESRCH; 1189 task->make_it_fail = make_it_fail; 1190 put_task_struct(task); 1191 1192 return count; 1193 } 1194 1195 static const struct file_operations proc_fault_inject_operations = { 1196 .read = proc_fault_inject_read, 1197 .write = proc_fault_inject_write, 1198 .llseek = generic_file_llseek, 1199 }; 1200 #endif 1201 1202 1203 #ifdef CONFIG_SCHED_DEBUG 1204 /* 1205 * Print out various scheduling related per-task fields: 1206 */ 1207 static int sched_show(struct seq_file *m, void *v) 1208 { 1209 struct inode *inode = m->private; 1210 struct task_struct *p; 1211 1212 p = get_proc_task(inode); 1213 if (!p) 1214 return -ESRCH; 1215 proc_sched_show_task(p, m); 1216 1217 put_task_struct(p); 1218 1219 return 0; 1220 } 1221 1222 static ssize_t 1223 sched_write(struct file *file, const char __user *buf, 1224 size_t count, loff_t *offset) 1225 { 1226 struct inode *inode = file->f_path.dentry->d_inode; 1227 struct task_struct *p; 1228 1229 p = get_proc_task(inode); 1230 if (!p) 1231 return -ESRCH; 1232 proc_sched_set_task(p); 1233 1234 put_task_struct(p); 1235 1236 return count; 1237 } 1238 1239 static int sched_open(struct inode *inode, struct file *filp) 1240 { 1241 int ret; 1242 1243 ret = single_open(filp, sched_show, NULL); 1244 if (!ret) { 1245 struct seq_file *m = filp->private_data; 1246 1247 m->private = inode; 1248 } 1249 return ret; 1250 } 1251 1252 static const struct file_operations proc_pid_sched_operations = { 1253 .open = sched_open, 1254 .read = seq_read, 1255 .write = sched_write, 1256 .llseek = seq_lseek, 1257 .release = single_release, 1258 }; 1259 1260 #endif 1261 1262 static ssize_t comm_write(struct file *file, const char __user *buf, 1263 size_t count, loff_t *offset) 1264 { 1265 struct inode *inode = file->f_path.dentry->d_inode; 1266 struct task_struct *p; 1267 char buffer[TASK_COMM_LEN]; 1268 1269 memset(buffer, 0, sizeof(buffer)); 1270 if (count > sizeof(buffer) - 1) 1271 count = sizeof(buffer) - 1; 1272 if (copy_from_user(buffer, buf, count)) 1273 return -EFAULT; 1274 1275 p = get_proc_task(inode); 1276 if (!p) 1277 return -ESRCH; 1278 1279 if (same_thread_group(current, p)) 1280 set_task_comm(p, buffer); 1281 else 1282 count = -EINVAL; 1283 1284 put_task_struct(p); 1285 1286 return count; 1287 } 1288 1289 static int comm_show(struct seq_file *m, void *v) 1290 { 1291 struct inode *inode = m->private; 1292 struct task_struct *p; 1293 1294 p = get_proc_task(inode); 1295 if (!p) 1296 return -ESRCH; 1297 1298 task_lock(p); 1299 seq_printf(m, "%s\n", p->comm); 1300 task_unlock(p); 1301 1302 put_task_struct(p); 1303 1304 return 0; 1305 } 1306 1307 static int comm_open(struct inode *inode, struct file *filp) 1308 { 1309 int ret; 1310 1311 ret = single_open(filp, comm_show, NULL); 1312 if (!ret) { 1313 struct seq_file *m = filp->private_data; 1314 1315 m->private = inode; 1316 } 1317 return ret; 1318 } 1319 1320 static const struct file_operations proc_pid_set_comm_operations = { 1321 .open = comm_open, 1322 .read = seq_read, 1323 .write = comm_write, 1324 .llseek = seq_lseek, 1325 .release = single_release, 1326 }; 1327 1328 /* 1329 * We added or removed a vma mapping the executable. The vmas are only mapped 1330 * during exec and are not mapped with the mmap system call. 1331 * Callers must hold down_write() on the mm's mmap_sem for these 1332 */ 1333 void added_exe_file_vma(struct mm_struct *mm) 1334 { 1335 mm->num_exe_file_vmas++; 1336 } 1337 1338 void removed_exe_file_vma(struct mm_struct *mm) 1339 { 1340 mm->num_exe_file_vmas--; 1341 if ((mm->num_exe_file_vmas == 0) && mm->exe_file){ 1342 fput(mm->exe_file); 1343 mm->exe_file = NULL; 1344 } 1345 1346 } 1347 1348 void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file) 1349 { 1350 if (new_exe_file) 1351 get_file(new_exe_file); 1352 if (mm->exe_file) 1353 fput(mm->exe_file); 1354 mm->exe_file = new_exe_file; 1355 mm->num_exe_file_vmas = 0; 1356 } 1357 1358 struct file *get_mm_exe_file(struct mm_struct *mm) 1359 { 1360 struct file *exe_file; 1361 1362 /* We need mmap_sem to protect against races with removal of 1363 * VM_EXECUTABLE vmas */ 1364 down_read(&mm->mmap_sem); 1365 exe_file = mm->exe_file; 1366 if (exe_file) 1367 get_file(exe_file); 1368 up_read(&mm->mmap_sem); 1369 return exe_file; 1370 } 1371 1372 void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm) 1373 { 1374 /* It's safe to write the exe_file pointer without exe_file_lock because 1375 * this is called during fork when the task is not yet in /proc */ 1376 newmm->exe_file = get_mm_exe_file(oldmm); 1377 } 1378 1379 static int proc_exe_link(struct inode *inode, struct path *exe_path) 1380 { 1381 struct task_struct *task; 1382 struct mm_struct *mm; 1383 struct file *exe_file; 1384 1385 task = get_proc_task(inode); 1386 if (!task) 1387 return -ENOENT; 1388 mm = get_task_mm(task); 1389 put_task_struct(task); 1390 if (!mm) 1391 return -ENOENT; 1392 exe_file = get_mm_exe_file(mm); 1393 mmput(mm); 1394 if (exe_file) { 1395 *exe_path = exe_file->f_path; 1396 path_get(&exe_file->f_path); 1397 fput(exe_file); 1398 return 0; 1399 } else 1400 return -ENOENT; 1401 } 1402 1403 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1404 { 1405 struct inode *inode = dentry->d_inode; 1406 int error = -EACCES; 1407 1408 /* We don't need a base pointer in the /proc filesystem */ 1409 path_put(&nd->path); 1410 1411 /* Are we allowed to snoop on the tasks file descriptors? */ 1412 if (!proc_fd_access_allowed(inode)) 1413 goto out; 1414 1415 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path); 1416 out: 1417 return ERR_PTR(error); 1418 } 1419 1420 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1421 { 1422 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1423 char *pathname; 1424 int len; 1425 1426 if (!tmp) 1427 return -ENOMEM; 1428 1429 pathname = d_path(path, tmp, PAGE_SIZE); 1430 len = PTR_ERR(pathname); 1431 if (IS_ERR(pathname)) 1432 goto out; 1433 len = tmp + PAGE_SIZE - 1 - pathname; 1434 1435 if (len > buflen) 1436 len = buflen; 1437 if (copy_to_user(buffer, pathname, len)) 1438 len = -EFAULT; 1439 out: 1440 free_page((unsigned long)tmp); 1441 return len; 1442 } 1443 1444 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1445 { 1446 int error = -EACCES; 1447 struct inode *inode = dentry->d_inode; 1448 struct path path; 1449 1450 /* Are we allowed to snoop on the tasks file descriptors? */ 1451 if (!proc_fd_access_allowed(inode)) 1452 goto out; 1453 1454 error = PROC_I(inode)->op.proc_get_link(inode, &path); 1455 if (error) 1456 goto out; 1457 1458 error = do_proc_readlink(&path, buffer, buflen); 1459 path_put(&path); 1460 out: 1461 return error; 1462 } 1463 1464 static const struct inode_operations proc_pid_link_inode_operations = { 1465 .readlink = proc_pid_readlink, 1466 .follow_link = proc_pid_follow_link, 1467 .setattr = proc_setattr, 1468 }; 1469 1470 1471 /* building an inode */ 1472 1473 static int task_dumpable(struct task_struct *task) 1474 { 1475 int dumpable = 0; 1476 struct mm_struct *mm; 1477 1478 task_lock(task); 1479 mm = task->mm; 1480 if (mm) 1481 dumpable = get_dumpable(mm); 1482 task_unlock(task); 1483 if(dumpable == 1) 1484 return 1; 1485 return 0; 1486 } 1487 1488 1489 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) 1490 { 1491 struct inode * inode; 1492 struct proc_inode *ei; 1493 const struct cred *cred; 1494 1495 /* We need a new inode */ 1496 1497 inode = new_inode(sb); 1498 if (!inode) 1499 goto out; 1500 1501 /* Common stuff */ 1502 ei = PROC_I(inode); 1503 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1504 inode->i_op = &proc_def_inode_operations; 1505 1506 /* 1507 * grab the reference to task. 1508 */ 1509 ei->pid = get_task_pid(task, PIDTYPE_PID); 1510 if (!ei->pid) 1511 goto out_unlock; 1512 1513 if (task_dumpable(task)) { 1514 rcu_read_lock(); 1515 cred = __task_cred(task); 1516 inode->i_uid = cred->euid; 1517 inode->i_gid = cred->egid; 1518 rcu_read_unlock(); 1519 } 1520 security_task_to_inode(task, inode); 1521 1522 out: 1523 return inode; 1524 1525 out_unlock: 1526 iput(inode); 1527 return NULL; 1528 } 1529 1530 static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 1531 { 1532 struct inode *inode = dentry->d_inode; 1533 struct task_struct *task; 1534 const struct cred *cred; 1535 1536 generic_fillattr(inode, stat); 1537 1538 rcu_read_lock(); 1539 stat->uid = 0; 1540 stat->gid = 0; 1541 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1542 if (task) { 1543 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1544 task_dumpable(task)) { 1545 cred = __task_cred(task); 1546 stat->uid = cred->euid; 1547 stat->gid = cred->egid; 1548 } 1549 } 1550 rcu_read_unlock(); 1551 return 0; 1552 } 1553 1554 /* dentry stuff */ 1555 1556 /* 1557 * Exceptional case: normally we are not allowed to unhash a busy 1558 * directory. In this case, however, we can do it - no aliasing problems 1559 * due to the way we treat inodes. 1560 * 1561 * Rewrite the inode's ownerships here because the owning task may have 1562 * performed a setuid(), etc. 1563 * 1564 * Before the /proc/pid/status file was created the only way to read 1565 * the effective uid of a /process was to stat /proc/pid. Reading 1566 * /proc/pid/status is slow enough that procps and other packages 1567 * kept stating /proc/pid. To keep the rules in /proc simple I have 1568 * made this apply to all per process world readable and executable 1569 * directories. 1570 */ 1571 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) 1572 { 1573 struct inode *inode = dentry->d_inode; 1574 struct task_struct *task = get_proc_task(inode); 1575 const struct cred *cred; 1576 1577 if (task) { 1578 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1579 task_dumpable(task)) { 1580 rcu_read_lock(); 1581 cred = __task_cred(task); 1582 inode->i_uid = cred->euid; 1583 inode->i_gid = cred->egid; 1584 rcu_read_unlock(); 1585 } else { 1586 inode->i_uid = 0; 1587 inode->i_gid = 0; 1588 } 1589 inode->i_mode &= ~(S_ISUID | S_ISGID); 1590 security_task_to_inode(task, inode); 1591 put_task_struct(task); 1592 return 1; 1593 } 1594 d_drop(dentry); 1595 return 0; 1596 } 1597 1598 static int pid_delete_dentry(struct dentry * dentry) 1599 { 1600 /* Is the task we represent dead? 1601 * If so, then don't put the dentry on the lru list, 1602 * kill it immediately. 1603 */ 1604 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first; 1605 } 1606 1607 static const struct dentry_operations pid_dentry_operations = 1608 { 1609 .d_revalidate = pid_revalidate, 1610 .d_delete = pid_delete_dentry, 1611 }; 1612 1613 /* Lookups */ 1614 1615 typedef struct dentry *instantiate_t(struct inode *, struct dentry *, 1616 struct task_struct *, const void *); 1617 1618 /* 1619 * Fill a directory entry. 1620 * 1621 * If possible create the dcache entry and derive our inode number and 1622 * file type from dcache entry. 1623 * 1624 * Since all of the proc inode numbers are dynamically generated, the inode 1625 * numbers do not exist until the inode is cache. This means creating the 1626 * the dcache entry in readdir is necessary to keep the inode numbers 1627 * reported by readdir in sync with the inode numbers reported 1628 * by stat. 1629 */ 1630 static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 1631 char *name, int len, 1632 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1633 { 1634 struct dentry *child, *dir = filp->f_path.dentry; 1635 struct inode *inode; 1636 struct qstr qname; 1637 ino_t ino = 0; 1638 unsigned type = DT_UNKNOWN; 1639 1640 qname.name = name; 1641 qname.len = len; 1642 qname.hash = full_name_hash(name, len); 1643 1644 child = d_lookup(dir, &qname); 1645 if (!child) { 1646 struct dentry *new; 1647 new = d_alloc(dir, &qname); 1648 if (new) { 1649 child = instantiate(dir->d_inode, new, task, ptr); 1650 if (child) 1651 dput(new); 1652 else 1653 child = new; 1654 } 1655 } 1656 if (!child || IS_ERR(child) || !child->d_inode) 1657 goto end_instantiate; 1658 inode = child->d_inode; 1659 if (inode) { 1660 ino = inode->i_ino; 1661 type = inode->i_mode >> 12; 1662 } 1663 dput(child); 1664 end_instantiate: 1665 if (!ino) 1666 ino = find_inode_number(dir, &qname); 1667 if (!ino) 1668 ino = 1; 1669 return filldir(dirent, name, len, filp->f_pos, ino, type); 1670 } 1671 1672 static unsigned name_to_int(struct dentry *dentry) 1673 { 1674 const char *name = dentry->d_name.name; 1675 int len = dentry->d_name.len; 1676 unsigned n = 0; 1677 1678 if (len > 1 && *name == '0') 1679 goto out; 1680 while (len-- > 0) { 1681 unsigned c = *name++ - '0'; 1682 if (c > 9) 1683 goto out; 1684 if (n >= (~0U-9)/10) 1685 goto out; 1686 n *= 10; 1687 n += c; 1688 } 1689 return n; 1690 out: 1691 return ~0U; 1692 } 1693 1694 #define PROC_FDINFO_MAX 64 1695 1696 static int proc_fd_info(struct inode *inode, struct path *path, char *info) 1697 { 1698 struct task_struct *task = get_proc_task(inode); 1699 struct files_struct *files = NULL; 1700 struct file *file; 1701 int fd = proc_fd(inode); 1702 1703 if (task) { 1704 files = get_files_struct(task); 1705 put_task_struct(task); 1706 } 1707 if (files) { 1708 /* 1709 * We are not taking a ref to the file structure, so we must 1710 * hold ->file_lock. 1711 */ 1712 spin_lock(&files->file_lock); 1713 file = fcheck_files(files, fd); 1714 if (file) { 1715 if (path) { 1716 *path = file->f_path; 1717 path_get(&file->f_path); 1718 } 1719 if (info) 1720 snprintf(info, PROC_FDINFO_MAX, 1721 "pos:\t%lli\n" 1722 "flags:\t0%o\n", 1723 (long long) file->f_pos, 1724 file->f_flags); 1725 spin_unlock(&files->file_lock); 1726 put_files_struct(files); 1727 return 0; 1728 } 1729 spin_unlock(&files->file_lock); 1730 put_files_struct(files); 1731 } 1732 return -ENOENT; 1733 } 1734 1735 static int proc_fd_link(struct inode *inode, struct path *path) 1736 { 1737 return proc_fd_info(inode, path, NULL); 1738 } 1739 1740 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) 1741 { 1742 struct inode *inode = dentry->d_inode; 1743 struct task_struct *task = get_proc_task(inode); 1744 int fd = proc_fd(inode); 1745 struct files_struct *files; 1746 const struct cred *cred; 1747 1748 if (task) { 1749 files = get_files_struct(task); 1750 if (files) { 1751 rcu_read_lock(); 1752 if (fcheck_files(files, fd)) { 1753 rcu_read_unlock(); 1754 put_files_struct(files); 1755 if (task_dumpable(task)) { 1756 rcu_read_lock(); 1757 cred = __task_cred(task); 1758 inode->i_uid = cred->euid; 1759 inode->i_gid = cred->egid; 1760 rcu_read_unlock(); 1761 } else { 1762 inode->i_uid = 0; 1763 inode->i_gid = 0; 1764 } 1765 inode->i_mode &= ~(S_ISUID | S_ISGID); 1766 security_task_to_inode(task, inode); 1767 put_task_struct(task); 1768 return 1; 1769 } 1770 rcu_read_unlock(); 1771 put_files_struct(files); 1772 } 1773 put_task_struct(task); 1774 } 1775 d_drop(dentry); 1776 return 0; 1777 } 1778 1779 static const struct dentry_operations tid_fd_dentry_operations = 1780 { 1781 .d_revalidate = tid_fd_revalidate, 1782 .d_delete = pid_delete_dentry, 1783 }; 1784 1785 static struct dentry *proc_fd_instantiate(struct inode *dir, 1786 struct dentry *dentry, struct task_struct *task, const void *ptr) 1787 { 1788 unsigned fd = *(const unsigned *)ptr; 1789 struct file *file; 1790 struct files_struct *files; 1791 struct inode *inode; 1792 struct proc_inode *ei; 1793 struct dentry *error = ERR_PTR(-ENOENT); 1794 1795 inode = proc_pid_make_inode(dir->i_sb, task); 1796 if (!inode) 1797 goto out; 1798 ei = PROC_I(inode); 1799 ei->fd = fd; 1800 files = get_files_struct(task); 1801 if (!files) 1802 goto out_iput; 1803 inode->i_mode = S_IFLNK; 1804 1805 /* 1806 * We are not taking a ref to the file structure, so we must 1807 * hold ->file_lock. 1808 */ 1809 spin_lock(&files->file_lock); 1810 file = fcheck_files(files, fd); 1811 if (!file) 1812 goto out_unlock; 1813 if (file->f_mode & FMODE_READ) 1814 inode->i_mode |= S_IRUSR | S_IXUSR; 1815 if (file->f_mode & FMODE_WRITE) 1816 inode->i_mode |= S_IWUSR | S_IXUSR; 1817 spin_unlock(&files->file_lock); 1818 put_files_struct(files); 1819 1820 inode->i_op = &proc_pid_link_inode_operations; 1821 inode->i_size = 64; 1822 ei->op.proc_get_link = proc_fd_link; 1823 dentry->d_op = &tid_fd_dentry_operations; 1824 d_add(dentry, inode); 1825 /* Close the race of the process dying before we return the dentry */ 1826 if (tid_fd_revalidate(dentry, NULL)) 1827 error = NULL; 1828 1829 out: 1830 return error; 1831 out_unlock: 1832 spin_unlock(&files->file_lock); 1833 put_files_struct(files); 1834 out_iput: 1835 iput(inode); 1836 goto out; 1837 } 1838 1839 static struct dentry *proc_lookupfd_common(struct inode *dir, 1840 struct dentry *dentry, 1841 instantiate_t instantiate) 1842 { 1843 struct task_struct *task = get_proc_task(dir); 1844 unsigned fd = name_to_int(dentry); 1845 struct dentry *result = ERR_PTR(-ENOENT); 1846 1847 if (!task) 1848 goto out_no_task; 1849 if (fd == ~0U) 1850 goto out; 1851 1852 result = instantiate(dir, dentry, task, &fd); 1853 out: 1854 put_task_struct(task); 1855 out_no_task: 1856 return result; 1857 } 1858 1859 static int proc_readfd_common(struct file * filp, void * dirent, 1860 filldir_t filldir, instantiate_t instantiate) 1861 { 1862 struct dentry *dentry = filp->f_path.dentry; 1863 struct inode *inode = dentry->d_inode; 1864 struct task_struct *p = get_proc_task(inode); 1865 unsigned int fd, ino; 1866 int retval; 1867 struct files_struct * files; 1868 1869 retval = -ENOENT; 1870 if (!p) 1871 goto out_no_task; 1872 retval = 0; 1873 1874 fd = filp->f_pos; 1875 switch (fd) { 1876 case 0: 1877 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) 1878 goto out; 1879 filp->f_pos++; 1880 case 1: 1881 ino = parent_ino(dentry); 1882 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1883 goto out; 1884 filp->f_pos++; 1885 default: 1886 files = get_files_struct(p); 1887 if (!files) 1888 goto out; 1889 rcu_read_lock(); 1890 for (fd = filp->f_pos-2; 1891 fd < files_fdtable(files)->max_fds; 1892 fd++, filp->f_pos++) { 1893 char name[PROC_NUMBUF]; 1894 int len; 1895 1896 if (!fcheck_files(files, fd)) 1897 continue; 1898 rcu_read_unlock(); 1899 1900 len = snprintf(name, sizeof(name), "%d", fd); 1901 if (proc_fill_cache(filp, dirent, filldir, 1902 name, len, instantiate, 1903 p, &fd) < 0) { 1904 rcu_read_lock(); 1905 break; 1906 } 1907 rcu_read_lock(); 1908 } 1909 rcu_read_unlock(); 1910 put_files_struct(files); 1911 } 1912 out: 1913 put_task_struct(p); 1914 out_no_task: 1915 return retval; 1916 } 1917 1918 static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry, 1919 struct nameidata *nd) 1920 { 1921 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate); 1922 } 1923 1924 static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir) 1925 { 1926 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate); 1927 } 1928 1929 static ssize_t proc_fdinfo_read(struct file *file, char __user *buf, 1930 size_t len, loff_t *ppos) 1931 { 1932 char tmp[PROC_FDINFO_MAX]; 1933 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp); 1934 if (!err) 1935 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp)); 1936 return err; 1937 } 1938 1939 static const struct file_operations proc_fdinfo_file_operations = { 1940 .open = nonseekable_open, 1941 .read = proc_fdinfo_read, 1942 }; 1943 1944 static const struct file_operations proc_fd_operations = { 1945 .read = generic_read_dir, 1946 .readdir = proc_readfd, 1947 }; 1948 1949 /* 1950 * /proc/pid/fd needs a special permission handler so that a process can still 1951 * access /proc/self/fd after it has executed a setuid(). 1952 */ 1953 static int proc_fd_permission(struct inode *inode, int mask) 1954 { 1955 int rv; 1956 1957 rv = generic_permission(inode, mask, NULL); 1958 if (rv == 0) 1959 return 0; 1960 if (task_pid(current) == proc_pid(inode)) 1961 rv = 0; 1962 return rv; 1963 } 1964 1965 /* 1966 * proc directories can do almost nothing.. 1967 */ 1968 static const struct inode_operations proc_fd_inode_operations = { 1969 .lookup = proc_lookupfd, 1970 .permission = proc_fd_permission, 1971 .setattr = proc_setattr, 1972 }; 1973 1974 static struct dentry *proc_fdinfo_instantiate(struct inode *dir, 1975 struct dentry *dentry, struct task_struct *task, const void *ptr) 1976 { 1977 unsigned fd = *(unsigned *)ptr; 1978 struct inode *inode; 1979 struct proc_inode *ei; 1980 struct dentry *error = ERR_PTR(-ENOENT); 1981 1982 inode = proc_pid_make_inode(dir->i_sb, task); 1983 if (!inode) 1984 goto out; 1985 ei = PROC_I(inode); 1986 ei->fd = fd; 1987 inode->i_mode = S_IFREG | S_IRUSR; 1988 inode->i_fop = &proc_fdinfo_file_operations; 1989 dentry->d_op = &tid_fd_dentry_operations; 1990 d_add(dentry, inode); 1991 /* Close the race of the process dying before we return the dentry */ 1992 if (tid_fd_revalidate(dentry, NULL)) 1993 error = NULL; 1994 1995 out: 1996 return error; 1997 } 1998 1999 static struct dentry *proc_lookupfdinfo(struct inode *dir, 2000 struct dentry *dentry, 2001 struct nameidata *nd) 2002 { 2003 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate); 2004 } 2005 2006 static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir) 2007 { 2008 return proc_readfd_common(filp, dirent, filldir, 2009 proc_fdinfo_instantiate); 2010 } 2011 2012 static const struct file_operations proc_fdinfo_operations = { 2013 .read = generic_read_dir, 2014 .readdir = proc_readfdinfo, 2015 }; 2016 2017 /* 2018 * proc directories can do almost nothing.. 2019 */ 2020 static const struct inode_operations proc_fdinfo_inode_operations = { 2021 .lookup = proc_lookupfdinfo, 2022 .setattr = proc_setattr, 2023 }; 2024 2025 2026 static struct dentry *proc_pident_instantiate(struct inode *dir, 2027 struct dentry *dentry, struct task_struct *task, const void *ptr) 2028 { 2029 const struct pid_entry *p = ptr; 2030 struct inode *inode; 2031 struct proc_inode *ei; 2032 struct dentry *error = ERR_PTR(-ENOENT); 2033 2034 inode = proc_pid_make_inode(dir->i_sb, task); 2035 if (!inode) 2036 goto out; 2037 2038 ei = PROC_I(inode); 2039 inode->i_mode = p->mode; 2040 if (S_ISDIR(inode->i_mode)) 2041 inode->i_nlink = 2; /* Use getattr to fix if necessary */ 2042 if (p->iop) 2043 inode->i_op = p->iop; 2044 if (p->fop) 2045 inode->i_fop = p->fop; 2046 ei->op = p->op; 2047 dentry->d_op = &pid_dentry_operations; 2048 d_add(dentry, inode); 2049 /* Close the race of the process dying before we return the dentry */ 2050 if (pid_revalidate(dentry, NULL)) 2051 error = NULL; 2052 out: 2053 return error; 2054 } 2055 2056 static struct dentry *proc_pident_lookup(struct inode *dir, 2057 struct dentry *dentry, 2058 const struct pid_entry *ents, 2059 unsigned int nents) 2060 { 2061 struct dentry *error; 2062 struct task_struct *task = get_proc_task(dir); 2063 const struct pid_entry *p, *last; 2064 2065 error = ERR_PTR(-ENOENT); 2066 2067 if (!task) 2068 goto out_no_task; 2069 2070 /* 2071 * Yes, it does not scale. And it should not. Don't add 2072 * new entries into /proc/<tgid>/ without very good reasons. 2073 */ 2074 last = &ents[nents - 1]; 2075 for (p = ents; p <= last; p++) { 2076 if (p->len != dentry->d_name.len) 2077 continue; 2078 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2079 break; 2080 } 2081 if (p > last) 2082 goto out; 2083 2084 error = proc_pident_instantiate(dir, dentry, task, p); 2085 out: 2086 put_task_struct(task); 2087 out_no_task: 2088 return error; 2089 } 2090 2091 static int proc_pident_fill_cache(struct file *filp, void *dirent, 2092 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 2093 { 2094 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 2095 proc_pident_instantiate, task, p); 2096 } 2097 2098 static int proc_pident_readdir(struct file *filp, 2099 void *dirent, filldir_t filldir, 2100 const struct pid_entry *ents, unsigned int nents) 2101 { 2102 int i; 2103 struct dentry *dentry = filp->f_path.dentry; 2104 struct inode *inode = dentry->d_inode; 2105 struct task_struct *task = get_proc_task(inode); 2106 const struct pid_entry *p, *last; 2107 ino_t ino; 2108 int ret; 2109 2110 ret = -ENOENT; 2111 if (!task) 2112 goto out_no_task; 2113 2114 ret = 0; 2115 i = filp->f_pos; 2116 switch (i) { 2117 case 0: 2118 ino = inode->i_ino; 2119 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 2120 goto out; 2121 i++; 2122 filp->f_pos++; 2123 /* fall through */ 2124 case 1: 2125 ino = parent_ino(dentry); 2126 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 2127 goto out; 2128 i++; 2129 filp->f_pos++; 2130 /* fall through */ 2131 default: 2132 i -= 2; 2133 if (i >= nents) { 2134 ret = 1; 2135 goto out; 2136 } 2137 p = ents + i; 2138 last = &ents[nents - 1]; 2139 while (p <= last) { 2140 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) 2141 goto out; 2142 filp->f_pos++; 2143 p++; 2144 } 2145 } 2146 2147 ret = 1; 2148 out: 2149 put_task_struct(task); 2150 out_no_task: 2151 return ret; 2152 } 2153 2154 #ifdef CONFIG_SECURITY 2155 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 2156 size_t count, loff_t *ppos) 2157 { 2158 struct inode * inode = file->f_path.dentry->d_inode; 2159 char *p = NULL; 2160 ssize_t length; 2161 struct task_struct *task = get_proc_task(inode); 2162 2163 if (!task) 2164 return -ESRCH; 2165 2166 length = security_getprocattr(task, 2167 (char*)file->f_path.dentry->d_name.name, 2168 &p); 2169 put_task_struct(task); 2170 if (length > 0) 2171 length = simple_read_from_buffer(buf, count, ppos, p, length); 2172 kfree(p); 2173 return length; 2174 } 2175 2176 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 2177 size_t count, loff_t *ppos) 2178 { 2179 struct inode * inode = file->f_path.dentry->d_inode; 2180 char *page; 2181 ssize_t length; 2182 struct task_struct *task = get_proc_task(inode); 2183 2184 length = -ESRCH; 2185 if (!task) 2186 goto out_no_task; 2187 if (count > PAGE_SIZE) 2188 count = PAGE_SIZE; 2189 2190 /* No partial writes. */ 2191 length = -EINVAL; 2192 if (*ppos != 0) 2193 goto out; 2194 2195 length = -ENOMEM; 2196 page = (char*)__get_free_page(GFP_TEMPORARY); 2197 if (!page) 2198 goto out; 2199 2200 length = -EFAULT; 2201 if (copy_from_user(page, buf, count)) 2202 goto out_free; 2203 2204 /* Guard against adverse ptrace interaction */ 2205 length = mutex_lock_interruptible(&task->cred_guard_mutex); 2206 if (length < 0) 2207 goto out_free; 2208 2209 length = security_setprocattr(task, 2210 (char*)file->f_path.dentry->d_name.name, 2211 (void*)page, count); 2212 mutex_unlock(&task->cred_guard_mutex); 2213 out_free: 2214 free_page((unsigned long) page); 2215 out: 2216 put_task_struct(task); 2217 out_no_task: 2218 return length; 2219 } 2220 2221 static const struct file_operations proc_pid_attr_operations = { 2222 .read = proc_pid_attr_read, 2223 .write = proc_pid_attr_write, 2224 .llseek = generic_file_llseek, 2225 }; 2226 2227 static const struct pid_entry attr_dir_stuff[] = { 2228 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2229 REG("prev", S_IRUGO, proc_pid_attr_operations), 2230 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2231 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2232 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2233 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), 2234 }; 2235 2236 static int proc_attr_dir_readdir(struct file * filp, 2237 void * dirent, filldir_t filldir) 2238 { 2239 return proc_pident_readdir(filp,dirent,filldir, 2240 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); 2241 } 2242 2243 static const struct file_operations proc_attr_dir_operations = { 2244 .read = generic_read_dir, 2245 .readdir = proc_attr_dir_readdir, 2246 }; 2247 2248 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2249 struct dentry *dentry, struct nameidata *nd) 2250 { 2251 return proc_pident_lookup(dir, dentry, 2252 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2253 } 2254 2255 static const struct inode_operations proc_attr_dir_inode_operations = { 2256 .lookup = proc_attr_dir_lookup, 2257 .getattr = pid_getattr, 2258 .setattr = proc_setattr, 2259 }; 2260 2261 #endif 2262 2263 #ifdef CONFIG_ELF_CORE 2264 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2265 size_t count, loff_t *ppos) 2266 { 2267 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 2268 struct mm_struct *mm; 2269 char buffer[PROC_NUMBUF]; 2270 size_t len; 2271 int ret; 2272 2273 if (!task) 2274 return -ESRCH; 2275 2276 ret = 0; 2277 mm = get_task_mm(task); 2278 if (mm) { 2279 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2280 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2281 MMF_DUMP_FILTER_SHIFT)); 2282 mmput(mm); 2283 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2284 } 2285 2286 put_task_struct(task); 2287 2288 return ret; 2289 } 2290 2291 static ssize_t proc_coredump_filter_write(struct file *file, 2292 const char __user *buf, 2293 size_t count, 2294 loff_t *ppos) 2295 { 2296 struct task_struct *task; 2297 struct mm_struct *mm; 2298 char buffer[PROC_NUMBUF], *end; 2299 unsigned int val; 2300 int ret; 2301 int i; 2302 unsigned long mask; 2303 2304 ret = -EFAULT; 2305 memset(buffer, 0, sizeof(buffer)); 2306 if (count > sizeof(buffer) - 1) 2307 count = sizeof(buffer) - 1; 2308 if (copy_from_user(buffer, buf, count)) 2309 goto out_no_task; 2310 2311 ret = -EINVAL; 2312 val = (unsigned int)simple_strtoul(buffer, &end, 0); 2313 if (*end == '\n') 2314 end++; 2315 if (end - buffer == 0) 2316 goto out_no_task; 2317 2318 ret = -ESRCH; 2319 task = get_proc_task(file->f_dentry->d_inode); 2320 if (!task) 2321 goto out_no_task; 2322 2323 ret = end - buffer; 2324 mm = get_task_mm(task); 2325 if (!mm) 2326 goto out_no_mm; 2327 2328 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2329 if (val & mask) 2330 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2331 else 2332 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2333 } 2334 2335 mmput(mm); 2336 out_no_mm: 2337 put_task_struct(task); 2338 out_no_task: 2339 return ret; 2340 } 2341 2342 static const struct file_operations proc_coredump_filter_operations = { 2343 .read = proc_coredump_filter_read, 2344 .write = proc_coredump_filter_write, 2345 .llseek = generic_file_llseek, 2346 }; 2347 #endif 2348 2349 /* 2350 * /proc/self: 2351 */ 2352 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 2353 int buflen) 2354 { 2355 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2356 pid_t tgid = task_tgid_nr_ns(current, ns); 2357 char tmp[PROC_NUMBUF]; 2358 if (!tgid) 2359 return -ENOENT; 2360 sprintf(tmp, "%d", tgid); 2361 return vfs_readlink(dentry,buffer,buflen,tmp); 2362 } 2363 2364 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 2365 { 2366 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2367 pid_t tgid = task_tgid_nr_ns(current, ns); 2368 char *name = ERR_PTR(-ENOENT); 2369 if (tgid) { 2370 name = __getname(); 2371 if (!name) 2372 name = ERR_PTR(-ENOMEM); 2373 else 2374 sprintf(name, "%d", tgid); 2375 } 2376 nd_set_link(nd, name); 2377 return NULL; 2378 } 2379 2380 static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd, 2381 void *cookie) 2382 { 2383 char *s = nd_get_link(nd); 2384 if (!IS_ERR(s)) 2385 __putname(s); 2386 } 2387 2388 static const struct inode_operations proc_self_inode_operations = { 2389 .readlink = proc_self_readlink, 2390 .follow_link = proc_self_follow_link, 2391 .put_link = proc_self_put_link, 2392 }; 2393 2394 /* 2395 * proc base 2396 * 2397 * These are the directory entries in the root directory of /proc 2398 * that properly belong to the /proc filesystem, as they describe 2399 * describe something that is process related. 2400 */ 2401 static const struct pid_entry proc_base_stuff[] = { 2402 NOD("self", S_IFLNK|S_IRWXUGO, 2403 &proc_self_inode_operations, NULL, {}), 2404 }; 2405 2406 /* 2407 * Exceptional case: normally we are not allowed to unhash a busy 2408 * directory. In this case, however, we can do it - no aliasing problems 2409 * due to the way we treat inodes. 2410 */ 2411 static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd) 2412 { 2413 struct inode *inode = dentry->d_inode; 2414 struct task_struct *task = get_proc_task(inode); 2415 if (task) { 2416 put_task_struct(task); 2417 return 1; 2418 } 2419 d_drop(dentry); 2420 return 0; 2421 } 2422 2423 static const struct dentry_operations proc_base_dentry_operations = 2424 { 2425 .d_revalidate = proc_base_revalidate, 2426 .d_delete = pid_delete_dentry, 2427 }; 2428 2429 static struct dentry *proc_base_instantiate(struct inode *dir, 2430 struct dentry *dentry, struct task_struct *task, const void *ptr) 2431 { 2432 const struct pid_entry *p = ptr; 2433 struct inode *inode; 2434 struct proc_inode *ei; 2435 struct dentry *error; 2436 2437 /* Allocate the inode */ 2438 error = ERR_PTR(-ENOMEM); 2439 inode = new_inode(dir->i_sb); 2440 if (!inode) 2441 goto out; 2442 2443 /* Initialize the inode */ 2444 ei = PROC_I(inode); 2445 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 2446 2447 /* 2448 * grab the reference to the task. 2449 */ 2450 ei->pid = get_task_pid(task, PIDTYPE_PID); 2451 if (!ei->pid) 2452 goto out_iput; 2453 2454 inode->i_mode = p->mode; 2455 if (S_ISDIR(inode->i_mode)) 2456 inode->i_nlink = 2; 2457 if (S_ISLNK(inode->i_mode)) 2458 inode->i_size = 64; 2459 if (p->iop) 2460 inode->i_op = p->iop; 2461 if (p->fop) 2462 inode->i_fop = p->fop; 2463 ei->op = p->op; 2464 dentry->d_op = &proc_base_dentry_operations; 2465 d_add(dentry, inode); 2466 error = NULL; 2467 out: 2468 return error; 2469 out_iput: 2470 iput(inode); 2471 goto out; 2472 } 2473 2474 static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) 2475 { 2476 struct dentry *error; 2477 struct task_struct *task = get_proc_task(dir); 2478 const struct pid_entry *p, *last; 2479 2480 error = ERR_PTR(-ENOENT); 2481 2482 if (!task) 2483 goto out_no_task; 2484 2485 /* Lookup the directory entry */ 2486 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1]; 2487 for (p = proc_base_stuff; p <= last; p++) { 2488 if (p->len != dentry->d_name.len) 2489 continue; 2490 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2491 break; 2492 } 2493 if (p > last) 2494 goto out; 2495 2496 error = proc_base_instantiate(dir, dentry, task, p); 2497 2498 out: 2499 put_task_struct(task); 2500 out_no_task: 2501 return error; 2502 } 2503 2504 static int proc_base_fill_cache(struct file *filp, void *dirent, 2505 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 2506 { 2507 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 2508 proc_base_instantiate, task, p); 2509 } 2510 2511 #ifdef CONFIG_TASK_IO_ACCOUNTING 2512 static int do_io_accounting(struct task_struct *task, char *buffer, int whole) 2513 { 2514 struct task_io_accounting acct = task->ioac; 2515 unsigned long flags; 2516 2517 if (whole && lock_task_sighand(task, &flags)) { 2518 struct task_struct *t = task; 2519 2520 task_io_accounting_add(&acct, &task->signal->ioac); 2521 while_each_thread(task, t) 2522 task_io_accounting_add(&acct, &t->ioac); 2523 2524 unlock_task_sighand(task, &flags); 2525 } 2526 return sprintf(buffer, 2527 "rchar: %llu\n" 2528 "wchar: %llu\n" 2529 "syscr: %llu\n" 2530 "syscw: %llu\n" 2531 "read_bytes: %llu\n" 2532 "write_bytes: %llu\n" 2533 "cancelled_write_bytes: %llu\n", 2534 (unsigned long long)acct.rchar, 2535 (unsigned long long)acct.wchar, 2536 (unsigned long long)acct.syscr, 2537 (unsigned long long)acct.syscw, 2538 (unsigned long long)acct.read_bytes, 2539 (unsigned long long)acct.write_bytes, 2540 (unsigned long long)acct.cancelled_write_bytes); 2541 } 2542 2543 static int proc_tid_io_accounting(struct task_struct *task, char *buffer) 2544 { 2545 return do_io_accounting(task, buffer, 0); 2546 } 2547 2548 static int proc_tgid_io_accounting(struct task_struct *task, char *buffer) 2549 { 2550 return do_io_accounting(task, buffer, 1); 2551 } 2552 #endif /* CONFIG_TASK_IO_ACCOUNTING */ 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 seq_printf(m, "%08x\n", task->personality); 2558 return 0; 2559 } 2560 2561 /* 2562 * Thread groups 2563 */ 2564 static const struct file_operations proc_task_operations; 2565 static const struct inode_operations proc_task_inode_operations; 2566 2567 static const struct pid_entry tgid_base_stuff[] = { 2568 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), 2569 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2570 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2571 #ifdef CONFIG_NET 2572 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), 2573 #endif 2574 REG("environ", S_IRUSR, proc_environ_operations), 2575 INF("auxv", S_IRUSR, proc_pid_auxv), 2576 ONE("status", S_IRUGO, proc_pid_status), 2577 ONE("personality", S_IRUSR, proc_pid_personality), 2578 INF("limits", S_IRUSR, proc_pid_limits), 2579 #ifdef CONFIG_SCHED_DEBUG 2580 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), 2581 #endif 2582 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), 2583 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK 2584 INF("syscall", S_IRUSR, proc_pid_syscall), 2585 #endif 2586 INF("cmdline", S_IRUGO, proc_pid_cmdline), 2587 ONE("stat", S_IRUGO, proc_tgid_stat), 2588 ONE("statm", S_IRUGO, proc_pid_statm), 2589 REG("maps", S_IRUGO, proc_maps_operations), 2590 #ifdef CONFIG_NUMA 2591 REG("numa_maps", S_IRUGO, proc_numa_maps_operations), 2592 #endif 2593 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2594 LNK("cwd", proc_cwd_link), 2595 LNK("root", proc_root_link), 2596 LNK("exe", proc_exe_link), 2597 REG("mounts", S_IRUGO, proc_mounts_operations), 2598 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2599 REG("mountstats", S_IRUSR, proc_mountstats_operations), 2600 #ifdef CONFIG_PROC_PAGE_MONITOR 2601 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2602 REG("smaps", S_IRUGO, proc_smaps_operations), 2603 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2604 #endif 2605 #ifdef CONFIG_SECURITY 2606 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2607 #endif 2608 #ifdef CONFIG_KALLSYMS 2609 INF("wchan", S_IRUGO, proc_pid_wchan), 2610 #endif 2611 #ifdef CONFIG_STACKTRACE 2612 ONE("stack", S_IRUSR, proc_pid_stack), 2613 #endif 2614 #ifdef CONFIG_SCHEDSTATS 2615 INF("schedstat", S_IRUGO, proc_pid_schedstat), 2616 #endif 2617 #ifdef CONFIG_LATENCYTOP 2618 REG("latency", S_IRUGO, proc_lstats_operations), 2619 #endif 2620 #ifdef CONFIG_PROC_PID_CPUSET 2621 REG("cpuset", S_IRUGO, proc_cpuset_operations), 2622 #endif 2623 #ifdef CONFIG_CGROUPS 2624 REG("cgroup", S_IRUGO, proc_cgroup_operations), 2625 #endif 2626 INF("oom_score", S_IRUGO, proc_oom_score), 2627 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations), 2628 #ifdef CONFIG_AUDITSYSCALL 2629 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2630 REG("sessionid", S_IRUGO, proc_sessionid_operations), 2631 #endif 2632 #ifdef CONFIG_FAULT_INJECTION 2633 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2634 #endif 2635 #ifdef CONFIG_ELF_CORE 2636 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), 2637 #endif 2638 #ifdef CONFIG_TASK_IO_ACCOUNTING 2639 INF("io", S_IRUGO, proc_tgid_io_accounting), 2640 #endif 2641 }; 2642 2643 static int proc_tgid_base_readdir(struct file * filp, 2644 void * dirent, filldir_t filldir) 2645 { 2646 return proc_pident_readdir(filp,dirent,filldir, 2647 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 2648 } 2649 2650 static const struct file_operations proc_tgid_base_operations = { 2651 .read = generic_read_dir, 2652 .readdir = proc_tgid_base_readdir, 2653 }; 2654 2655 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 2656 return proc_pident_lookup(dir, dentry, 2657 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2658 } 2659 2660 static const struct inode_operations proc_tgid_base_inode_operations = { 2661 .lookup = proc_tgid_base_lookup, 2662 .getattr = pid_getattr, 2663 .setattr = proc_setattr, 2664 }; 2665 2666 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 2667 { 2668 struct dentry *dentry, *leader, *dir; 2669 char buf[PROC_NUMBUF]; 2670 struct qstr name; 2671 2672 name.name = buf; 2673 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2674 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 2675 if (dentry) { 2676 shrink_dcache_parent(dentry); 2677 d_drop(dentry); 2678 dput(dentry); 2679 } 2680 2681 name.name = buf; 2682 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 2683 leader = d_hash_and_lookup(mnt->mnt_root, &name); 2684 if (!leader) 2685 goto out; 2686 2687 name.name = "task"; 2688 name.len = strlen(name.name); 2689 dir = d_hash_and_lookup(leader, &name); 2690 if (!dir) 2691 goto out_put_leader; 2692 2693 name.name = buf; 2694 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2695 dentry = d_hash_and_lookup(dir, &name); 2696 if (dentry) { 2697 shrink_dcache_parent(dentry); 2698 d_drop(dentry); 2699 dput(dentry); 2700 } 2701 2702 dput(dir); 2703 out_put_leader: 2704 dput(leader); 2705 out: 2706 return; 2707 } 2708 2709 /** 2710 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 2711 * @task: task that should be flushed. 2712 * 2713 * When flushing dentries from proc, one needs to flush them from global 2714 * proc (proc_mnt) and from all the namespaces' procs this task was seen 2715 * in. This call is supposed to do all of this job. 2716 * 2717 * Looks in the dcache for 2718 * /proc/@pid 2719 * /proc/@tgid/task/@pid 2720 * if either directory is present flushes it and all of it'ts children 2721 * from the dcache. 2722 * 2723 * It is safe and reasonable to cache /proc entries for a task until 2724 * that task exits. After that they just clog up the dcache with 2725 * useless entries, possibly causing useful dcache entries to be 2726 * flushed instead. This routine is proved to flush those useless 2727 * dcache entries at process exit time. 2728 * 2729 * NOTE: This routine is just an optimization so it does not guarantee 2730 * that no dcache entries will exist at process exit time it 2731 * just makes it very unlikely that any will persist. 2732 */ 2733 2734 void proc_flush_task(struct task_struct *task) 2735 { 2736 int i; 2737 struct pid *pid, *tgid; 2738 struct upid *upid; 2739 2740 pid = task_pid(task); 2741 tgid = task_tgid(task); 2742 2743 for (i = 0; i <= pid->level; i++) { 2744 upid = &pid->numbers[i]; 2745 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 2746 tgid->numbers[i].nr); 2747 } 2748 2749 upid = &pid->numbers[pid->level]; 2750 if (upid->nr == 1) 2751 pid_ns_release_proc(upid->ns); 2752 } 2753 2754 static struct dentry *proc_pid_instantiate(struct inode *dir, 2755 struct dentry * dentry, 2756 struct task_struct *task, const void *ptr) 2757 { 2758 struct dentry *error = ERR_PTR(-ENOENT); 2759 struct inode *inode; 2760 2761 inode = proc_pid_make_inode(dir->i_sb, task); 2762 if (!inode) 2763 goto out; 2764 2765 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2766 inode->i_op = &proc_tgid_base_inode_operations; 2767 inode->i_fop = &proc_tgid_base_operations; 2768 inode->i_flags|=S_IMMUTABLE; 2769 2770 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff, 2771 ARRAY_SIZE(tgid_base_stuff)); 2772 2773 dentry->d_op = &pid_dentry_operations; 2774 2775 d_add(dentry, inode); 2776 /* Close the race of the process dying before we return the dentry */ 2777 if (pid_revalidate(dentry, NULL)) 2778 error = NULL; 2779 out: 2780 return error; 2781 } 2782 2783 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2784 { 2785 struct dentry *result; 2786 struct task_struct *task; 2787 unsigned tgid; 2788 struct pid_namespace *ns; 2789 2790 result = proc_base_lookup(dir, dentry); 2791 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT) 2792 goto out; 2793 2794 tgid = name_to_int(dentry); 2795 if (tgid == ~0U) 2796 goto out; 2797 2798 ns = dentry->d_sb->s_fs_info; 2799 rcu_read_lock(); 2800 task = find_task_by_pid_ns(tgid, ns); 2801 if (task) 2802 get_task_struct(task); 2803 rcu_read_unlock(); 2804 if (!task) 2805 goto out; 2806 2807 result = proc_pid_instantiate(dir, dentry, task, NULL); 2808 put_task_struct(task); 2809 out: 2810 return result; 2811 } 2812 2813 /* 2814 * Find the first task with tgid >= tgid 2815 * 2816 */ 2817 struct tgid_iter { 2818 unsigned int tgid; 2819 struct task_struct *task; 2820 }; 2821 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 2822 { 2823 struct pid *pid; 2824 2825 if (iter.task) 2826 put_task_struct(iter.task); 2827 rcu_read_lock(); 2828 retry: 2829 iter.task = NULL; 2830 pid = find_ge_pid(iter.tgid, ns); 2831 if (pid) { 2832 iter.tgid = pid_nr_ns(pid, ns); 2833 iter.task = pid_task(pid, PIDTYPE_PID); 2834 /* What we to know is if the pid we have find is the 2835 * pid of a thread_group_leader. Testing for task 2836 * being a thread_group_leader is the obvious thing 2837 * todo but there is a window when it fails, due to 2838 * the pid transfer logic in de_thread. 2839 * 2840 * So we perform the straight forward test of seeing 2841 * if the pid we have found is the pid of a thread 2842 * group leader, and don't worry if the task we have 2843 * found doesn't happen to be a thread group leader. 2844 * As we don't care in the case of readdir. 2845 */ 2846 if (!iter.task || !has_group_leader_pid(iter.task)) { 2847 iter.tgid += 1; 2848 goto retry; 2849 } 2850 get_task_struct(iter.task); 2851 } 2852 rcu_read_unlock(); 2853 return iter; 2854 } 2855 2856 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff)) 2857 2858 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 2859 struct tgid_iter iter) 2860 { 2861 char name[PROC_NUMBUF]; 2862 int len = snprintf(name, sizeof(name), "%d", iter.tgid); 2863 return proc_fill_cache(filp, dirent, filldir, name, len, 2864 proc_pid_instantiate, iter.task, NULL); 2865 } 2866 2867 /* for the /proc/ directory itself, after non-process stuff has been done */ 2868 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2869 { 2870 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2871 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode); 2872 struct tgid_iter iter; 2873 struct pid_namespace *ns; 2874 2875 if (!reaper) 2876 goto out_no_task; 2877 2878 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { 2879 const struct pid_entry *p = &proc_base_stuff[nr]; 2880 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) 2881 goto out; 2882 } 2883 2884 ns = filp->f_dentry->d_sb->s_fs_info; 2885 iter.task = NULL; 2886 iter.tgid = filp->f_pos - TGID_OFFSET; 2887 for (iter = next_tgid(ns, iter); 2888 iter.task; 2889 iter.tgid += 1, iter = next_tgid(ns, iter)) { 2890 filp->f_pos = iter.tgid + TGID_OFFSET; 2891 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) { 2892 put_task_struct(iter.task); 2893 goto out; 2894 } 2895 } 2896 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; 2897 out: 2898 put_task_struct(reaper); 2899 out_no_task: 2900 return 0; 2901 } 2902 2903 /* 2904 * Tasks 2905 */ 2906 static const struct pid_entry tid_base_stuff[] = { 2907 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), 2908 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), 2909 REG("environ", S_IRUSR, proc_environ_operations), 2910 INF("auxv", S_IRUSR, proc_pid_auxv), 2911 ONE("status", S_IRUGO, proc_pid_status), 2912 ONE("personality", S_IRUSR, proc_pid_personality), 2913 INF("limits", S_IRUSR, 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 INF("syscall", S_IRUSR, proc_pid_syscall), 2920 #endif 2921 INF("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_maps_operations), 2925 #ifdef CONFIG_NUMA 2926 REG("numa_maps", S_IRUGO, proc_numa_maps_operations), 2927 #endif 2928 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), 2929 LNK("cwd", proc_cwd_link), 2930 LNK("root", proc_root_link), 2931 LNK("exe", proc_exe_link), 2932 REG("mounts", S_IRUGO, proc_mounts_operations), 2933 REG("mountinfo", S_IRUGO, proc_mountinfo_operations), 2934 #ifdef CONFIG_PROC_PAGE_MONITOR 2935 REG("clear_refs", S_IWUSR, proc_clear_refs_operations), 2936 REG("smaps", S_IRUGO, proc_smaps_operations), 2937 REG("pagemap", S_IRUSR, proc_pagemap_operations), 2938 #endif 2939 #ifdef CONFIG_SECURITY 2940 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), 2941 #endif 2942 #ifdef CONFIG_KALLSYMS 2943 INF("wchan", S_IRUGO, proc_pid_wchan), 2944 #endif 2945 #ifdef CONFIG_STACKTRACE 2946 ONE("stack", S_IRUSR, proc_pid_stack), 2947 #endif 2948 #ifdef CONFIG_SCHEDSTATS 2949 INF("schedstat", S_IRUGO, proc_pid_schedstat), 2950 #endif 2951 #ifdef CONFIG_LATENCYTOP 2952 REG("latency", S_IRUGO, proc_lstats_operations), 2953 #endif 2954 #ifdef CONFIG_PROC_PID_CPUSET 2955 REG("cpuset", S_IRUGO, proc_cpuset_operations), 2956 #endif 2957 #ifdef CONFIG_CGROUPS 2958 REG("cgroup", S_IRUGO, proc_cgroup_operations), 2959 #endif 2960 INF("oom_score", S_IRUGO, proc_oom_score), 2961 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations), 2962 #ifdef CONFIG_AUDITSYSCALL 2963 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), 2964 REG("sessionid", S_IRUSR, proc_sessionid_operations), 2965 #endif 2966 #ifdef CONFIG_FAULT_INJECTION 2967 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), 2968 #endif 2969 #ifdef CONFIG_TASK_IO_ACCOUNTING 2970 INF("io", S_IRUGO, proc_tid_io_accounting), 2971 #endif 2972 }; 2973 2974 static int proc_tid_base_readdir(struct file * filp, 2975 void * dirent, filldir_t filldir) 2976 { 2977 return proc_pident_readdir(filp,dirent,filldir, 2978 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 2979 } 2980 2981 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 2982 return proc_pident_lookup(dir, dentry, 2983 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 2984 } 2985 2986 static const struct file_operations proc_tid_base_operations = { 2987 .read = generic_read_dir, 2988 .readdir = proc_tid_base_readdir, 2989 }; 2990 2991 static const struct inode_operations proc_tid_base_inode_operations = { 2992 .lookup = proc_tid_base_lookup, 2993 .getattr = pid_getattr, 2994 .setattr = proc_setattr, 2995 }; 2996 2997 static struct dentry *proc_task_instantiate(struct inode *dir, 2998 struct dentry *dentry, struct task_struct *task, const void *ptr) 2999 { 3000 struct dentry *error = ERR_PTR(-ENOENT); 3001 struct inode *inode; 3002 inode = proc_pid_make_inode(dir->i_sb, task); 3003 3004 if (!inode) 3005 goto out; 3006 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 3007 inode->i_op = &proc_tid_base_inode_operations; 3008 inode->i_fop = &proc_tid_base_operations; 3009 inode->i_flags|=S_IMMUTABLE; 3010 3011 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff, 3012 ARRAY_SIZE(tid_base_stuff)); 3013 3014 dentry->d_op = &pid_dentry_operations; 3015 3016 d_add(dentry, inode); 3017 /* Close the race of the process dying before we return the dentry */ 3018 if (pid_revalidate(dentry, NULL)) 3019 error = NULL; 3020 out: 3021 return error; 3022 } 3023 3024 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 3025 { 3026 struct dentry *result = ERR_PTR(-ENOENT); 3027 struct task_struct *task; 3028 struct task_struct *leader = get_proc_task(dir); 3029 unsigned tid; 3030 struct pid_namespace *ns; 3031 3032 if (!leader) 3033 goto out_no_task; 3034 3035 tid = name_to_int(dentry); 3036 if (tid == ~0U) 3037 goto out; 3038 3039 ns = dentry->d_sb->s_fs_info; 3040 rcu_read_lock(); 3041 task = find_task_by_pid_ns(tid, ns); 3042 if (task) 3043 get_task_struct(task); 3044 rcu_read_unlock(); 3045 if (!task) 3046 goto out; 3047 if (!same_thread_group(leader, task)) 3048 goto out_drop_task; 3049 3050 result = proc_task_instantiate(dir, dentry, task, NULL); 3051 out_drop_task: 3052 put_task_struct(task); 3053 out: 3054 put_task_struct(leader); 3055 out_no_task: 3056 return result; 3057 } 3058 3059 /* 3060 * Find the first tid of a thread group to return to user space. 3061 * 3062 * Usually this is just the thread group leader, but if the users 3063 * buffer was too small or there was a seek into the middle of the 3064 * directory we have more work todo. 3065 * 3066 * In the case of a short read we start with find_task_by_pid. 3067 * 3068 * In the case of a seek we start with the leader and walk nr 3069 * threads past it. 3070 */ 3071 static struct task_struct *first_tid(struct task_struct *leader, 3072 int tid, int nr, struct pid_namespace *ns) 3073 { 3074 struct task_struct *pos; 3075 3076 rcu_read_lock(); 3077 /* Attempt to start with the pid of a thread */ 3078 if (tid && (nr > 0)) { 3079 pos = find_task_by_pid_ns(tid, ns); 3080 if (pos && (pos->group_leader == leader)) 3081 goto found; 3082 } 3083 3084 /* If nr exceeds the number of threads there is nothing todo */ 3085 pos = NULL; 3086 if (nr && nr >= get_nr_threads(leader)) 3087 goto out; 3088 3089 /* If we haven't found our starting place yet start 3090 * with the leader and walk nr threads forward. 3091 */ 3092 for (pos = leader; nr > 0; --nr) { 3093 pos = next_thread(pos); 3094 if (pos == leader) { 3095 pos = NULL; 3096 goto out; 3097 } 3098 } 3099 found: 3100 get_task_struct(pos); 3101 out: 3102 rcu_read_unlock(); 3103 return pos; 3104 } 3105 3106 /* 3107 * Find the next thread in the thread list. 3108 * Return NULL if there is an error or no next thread. 3109 * 3110 * The reference to the input task_struct is released. 3111 */ 3112 static struct task_struct *next_tid(struct task_struct *start) 3113 { 3114 struct task_struct *pos = NULL; 3115 rcu_read_lock(); 3116 if (pid_alive(start)) { 3117 pos = next_thread(start); 3118 if (thread_group_leader(pos)) 3119 pos = NULL; 3120 else 3121 get_task_struct(pos); 3122 } 3123 rcu_read_unlock(); 3124 put_task_struct(start); 3125 return pos; 3126 } 3127 3128 static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 3129 struct task_struct *task, int tid) 3130 { 3131 char name[PROC_NUMBUF]; 3132 int len = snprintf(name, sizeof(name), "%d", tid); 3133 return proc_fill_cache(filp, dirent, filldir, name, len, 3134 proc_task_instantiate, task, NULL); 3135 } 3136 3137 /* for the /proc/TGID/task/ directories */ 3138 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 3139 { 3140 struct dentry *dentry = filp->f_path.dentry; 3141 struct inode *inode = dentry->d_inode; 3142 struct task_struct *leader = NULL; 3143 struct task_struct *task; 3144 int retval = -ENOENT; 3145 ino_t ino; 3146 int tid; 3147 struct pid_namespace *ns; 3148 3149 task = get_proc_task(inode); 3150 if (!task) 3151 goto out_no_task; 3152 rcu_read_lock(); 3153 if (pid_alive(task)) { 3154 leader = task->group_leader; 3155 get_task_struct(leader); 3156 } 3157 rcu_read_unlock(); 3158 put_task_struct(task); 3159 if (!leader) 3160 goto out_no_task; 3161 retval = 0; 3162 3163 switch ((unsigned long)filp->f_pos) { 3164 case 0: 3165 ino = inode->i_ino; 3166 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0) 3167 goto out; 3168 filp->f_pos++; 3169 /* fall through */ 3170 case 1: 3171 ino = parent_ino(dentry); 3172 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0) 3173 goto out; 3174 filp->f_pos++; 3175 /* fall through */ 3176 } 3177 3178 /* f_version caches the tgid value that the last readdir call couldn't 3179 * return. lseek aka telldir automagically resets f_version to 0. 3180 */ 3181 ns = filp->f_dentry->d_sb->s_fs_info; 3182 tid = (int)filp->f_version; 3183 filp->f_version = 0; 3184 for (task = first_tid(leader, tid, filp->f_pos - 2, ns); 3185 task; 3186 task = next_tid(task), filp->f_pos++) { 3187 tid = task_pid_nr_ns(task, ns); 3188 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { 3189 /* returning this tgid failed, save it as the first 3190 * pid for the next readir call */ 3191 filp->f_version = (u64)tid; 3192 put_task_struct(task); 3193 break; 3194 } 3195 } 3196 out: 3197 put_task_struct(leader); 3198 out_no_task: 3199 return retval; 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 }; 3221 3222 static const struct file_operations proc_task_operations = { 3223 .read = generic_read_dir, 3224 .readdir = proc_task_readdir, 3225 }; 3226