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/init.h> 57 #include <linux/capability.h> 58 #include <linux/file.h> 59 #include <linux/string.h> 60 #include <linux/seq_file.h> 61 #include <linux/namei.h> 62 #include <linux/mnt_namespace.h> 63 #include <linux/mm.h> 64 #include <linux/rcupdate.h> 65 #include <linux/kallsyms.h> 66 #include <linux/resource.h> 67 #include <linux/module.h> 68 #include <linux/mount.h> 69 #include <linux/security.h> 70 #include <linux/ptrace.h> 71 #include <linux/cgroup.h> 72 #include <linux/cpuset.h> 73 #include <linux/audit.h> 74 #include <linux/poll.h> 75 #include <linux/nsproxy.h> 76 #include <linux/oom.h> 77 #include <linux/elf.h> 78 #include <linux/pid_namespace.h> 79 #include "internal.h" 80 81 /* NOTE: 82 * Implementing inode permission operations in /proc is almost 83 * certainly an error. Permission checks need to happen during 84 * each system call not at open time. The reason is that most of 85 * what we wish to check for permissions in /proc varies at runtime. 86 * 87 * The classic example of a problem is opening file descriptors 88 * in /proc for a task before it execs a suid executable. 89 */ 90 91 struct pid_entry { 92 char *name; 93 int len; 94 mode_t mode; 95 const struct inode_operations *iop; 96 const struct file_operations *fop; 97 union proc_op op; 98 }; 99 100 #define NOD(NAME, MODE, IOP, FOP, OP) { \ 101 .name = (NAME), \ 102 .len = sizeof(NAME) - 1, \ 103 .mode = MODE, \ 104 .iop = IOP, \ 105 .fop = FOP, \ 106 .op = OP, \ 107 } 108 109 #define DIR(NAME, MODE, OTYPE) \ 110 NOD(NAME, (S_IFDIR|(MODE)), \ 111 &proc_##OTYPE##_inode_operations, &proc_##OTYPE##_operations, \ 112 {} ) 113 #define LNK(NAME, OTYPE) \ 114 NOD(NAME, (S_IFLNK|S_IRWXUGO), \ 115 &proc_pid_link_inode_operations, NULL, \ 116 { .proc_get_link = &proc_##OTYPE##_link } ) 117 #define REG(NAME, MODE, OTYPE) \ 118 NOD(NAME, (S_IFREG|(MODE)), NULL, \ 119 &proc_##OTYPE##_operations, {}) 120 #define INF(NAME, MODE, OTYPE) \ 121 NOD(NAME, (S_IFREG|(MODE)), \ 122 NULL, &proc_info_file_operations, \ 123 { .proc_read = &proc_##OTYPE } ) 124 #define ONE(NAME, MODE, OTYPE) \ 125 NOD(NAME, (S_IFREG|(MODE)), \ 126 NULL, &proc_single_file_operations, \ 127 { .proc_show = &proc_##OTYPE } ) 128 129 int maps_protect; 130 EXPORT_SYMBOL(maps_protect); 131 132 static struct fs_struct *get_fs_struct(struct task_struct *task) 133 { 134 struct fs_struct *fs; 135 task_lock(task); 136 fs = task->fs; 137 if(fs) 138 atomic_inc(&fs->count); 139 task_unlock(task); 140 return fs; 141 } 142 143 static int get_nr_threads(struct task_struct *tsk) 144 { 145 /* Must be called with the rcu_read_lock held */ 146 unsigned long flags; 147 int count = 0; 148 149 if (lock_task_sighand(tsk, &flags)) { 150 count = atomic_read(&tsk->signal->count); 151 unlock_task_sighand(tsk, &flags); 152 } 153 return count; 154 } 155 156 static int proc_cwd_link(struct inode *inode, struct path *path) 157 { 158 struct task_struct *task = get_proc_task(inode); 159 struct fs_struct *fs = NULL; 160 int result = -ENOENT; 161 162 if (task) { 163 fs = get_fs_struct(task); 164 put_task_struct(task); 165 } 166 if (fs) { 167 read_lock(&fs->lock); 168 *path = fs->pwd; 169 path_get(&fs->pwd); 170 read_unlock(&fs->lock); 171 result = 0; 172 put_fs_struct(fs); 173 } 174 return result; 175 } 176 177 static int proc_root_link(struct inode *inode, struct path *path) 178 { 179 struct task_struct *task = get_proc_task(inode); 180 struct fs_struct *fs = NULL; 181 int result = -ENOENT; 182 183 if (task) { 184 fs = get_fs_struct(task); 185 put_task_struct(task); 186 } 187 if (fs) { 188 read_lock(&fs->lock); 189 *path = fs->root; 190 path_get(&fs->root); 191 read_unlock(&fs->lock); 192 result = 0; 193 put_fs_struct(fs); 194 } 195 return result; 196 } 197 198 #define MAY_PTRACE(task) \ 199 (task == current || \ 200 (task->parent == current && \ 201 (task->ptrace & PT_PTRACED) && \ 202 (task_is_stopped_or_traced(task)) && \ 203 security_ptrace(current,task) == 0)) 204 205 struct mm_struct *mm_for_maps(struct task_struct *task) 206 { 207 struct mm_struct *mm = get_task_mm(task); 208 if (!mm) 209 return NULL; 210 down_read(&mm->mmap_sem); 211 task_lock(task); 212 if (task->mm != mm) 213 goto out; 214 if (task->mm != current->mm && __ptrace_may_attach(task) < 0) 215 goto out; 216 task_unlock(task); 217 return mm; 218 out: 219 task_unlock(task); 220 up_read(&mm->mmap_sem); 221 mmput(mm); 222 return NULL; 223 } 224 225 static int proc_pid_cmdline(struct task_struct *task, char * buffer) 226 { 227 int res = 0; 228 unsigned int len; 229 struct mm_struct *mm = get_task_mm(task); 230 if (!mm) 231 goto out; 232 if (!mm->arg_end) 233 goto out_mm; /* Shh! No looking before we're done */ 234 235 len = mm->arg_end - mm->arg_start; 236 237 if (len > PAGE_SIZE) 238 len = PAGE_SIZE; 239 240 res = access_process_vm(task, mm->arg_start, buffer, len, 0); 241 242 // If the nul at the end of args has been overwritten, then 243 // assume application is using setproctitle(3). 244 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { 245 len = strnlen(buffer, res); 246 if (len < res) { 247 res = len; 248 } else { 249 len = mm->env_end - mm->env_start; 250 if (len > PAGE_SIZE - res) 251 len = PAGE_SIZE - res; 252 res += access_process_vm(task, mm->env_start, buffer+res, len, 0); 253 res = strnlen(buffer, res); 254 } 255 } 256 out_mm: 257 mmput(mm); 258 out: 259 return res; 260 } 261 262 static int proc_pid_auxv(struct task_struct *task, char *buffer) 263 { 264 int res = 0; 265 struct mm_struct *mm = get_task_mm(task); 266 if (mm) { 267 unsigned int nwords = 0; 268 do 269 nwords += 2; 270 while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 271 res = nwords * sizeof(mm->saved_auxv[0]); 272 if (res > PAGE_SIZE) 273 res = PAGE_SIZE; 274 memcpy(buffer, mm->saved_auxv, res); 275 mmput(mm); 276 } 277 return res; 278 } 279 280 281 #ifdef CONFIG_KALLSYMS 282 /* 283 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 284 * Returns the resolved symbol. If that fails, simply return the address. 285 */ 286 static int proc_pid_wchan(struct task_struct *task, char *buffer) 287 { 288 unsigned long wchan; 289 char symname[KSYM_NAME_LEN]; 290 291 wchan = get_wchan(task); 292 293 if (lookup_symbol_name(wchan, symname) < 0) 294 return sprintf(buffer, "%lu", wchan); 295 else 296 return sprintf(buffer, "%s", symname); 297 } 298 #endif /* CONFIG_KALLSYMS */ 299 300 #ifdef CONFIG_SCHEDSTATS 301 /* 302 * Provides /proc/PID/schedstat 303 */ 304 static int proc_pid_schedstat(struct task_struct *task, char *buffer) 305 { 306 return sprintf(buffer, "%llu %llu %lu\n", 307 task->sched_info.cpu_time, 308 task->sched_info.run_delay, 309 task->sched_info.pcount); 310 } 311 #endif 312 313 #ifdef CONFIG_LATENCYTOP 314 static int lstats_show_proc(struct seq_file *m, void *v) 315 { 316 int i; 317 struct inode *inode = m->private; 318 struct task_struct *task = get_proc_task(inode); 319 320 if (!task) 321 return -ESRCH; 322 seq_puts(m, "Latency Top version : v0.1\n"); 323 for (i = 0; i < 32; i++) { 324 if (task->latency_record[i].backtrace[0]) { 325 int q; 326 seq_printf(m, "%i %li %li ", 327 task->latency_record[i].count, 328 task->latency_record[i].time, 329 task->latency_record[i].max); 330 for (q = 0; q < LT_BACKTRACEDEPTH; q++) { 331 char sym[KSYM_NAME_LEN]; 332 char *c; 333 if (!task->latency_record[i].backtrace[q]) 334 break; 335 if (task->latency_record[i].backtrace[q] == ULONG_MAX) 336 break; 337 sprint_symbol(sym, task->latency_record[i].backtrace[q]); 338 c = strchr(sym, '+'); 339 if (c) 340 *c = 0; 341 seq_printf(m, "%s ", sym); 342 } 343 seq_printf(m, "\n"); 344 } 345 346 } 347 put_task_struct(task); 348 return 0; 349 } 350 351 static int lstats_open(struct inode *inode, struct file *file) 352 { 353 return single_open(file, lstats_show_proc, inode); 354 } 355 356 static ssize_t lstats_write(struct file *file, const char __user *buf, 357 size_t count, loff_t *offs) 358 { 359 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 360 361 if (!task) 362 return -ESRCH; 363 clear_all_latency_tracing(task); 364 put_task_struct(task); 365 366 return count; 367 } 368 369 static const struct file_operations proc_lstats_operations = { 370 .open = lstats_open, 371 .read = seq_read, 372 .write = lstats_write, 373 .llseek = seq_lseek, 374 .release = single_release, 375 }; 376 377 #endif 378 379 /* The badness from the OOM killer */ 380 unsigned long badness(struct task_struct *p, unsigned long uptime); 381 static int proc_oom_score(struct task_struct *task, char *buffer) 382 { 383 unsigned long points; 384 struct timespec uptime; 385 386 do_posix_clock_monotonic_gettime(&uptime); 387 read_lock(&tasklist_lock); 388 points = badness(task, uptime.tv_sec); 389 read_unlock(&tasklist_lock); 390 return sprintf(buffer, "%lu\n", points); 391 } 392 393 struct limit_names { 394 char *name; 395 char *unit; 396 }; 397 398 static const struct limit_names lnames[RLIM_NLIMITS] = { 399 [RLIMIT_CPU] = {"Max cpu time", "ms"}, 400 [RLIMIT_FSIZE] = {"Max file size", "bytes"}, 401 [RLIMIT_DATA] = {"Max data size", "bytes"}, 402 [RLIMIT_STACK] = {"Max stack size", "bytes"}, 403 [RLIMIT_CORE] = {"Max core file size", "bytes"}, 404 [RLIMIT_RSS] = {"Max resident set", "bytes"}, 405 [RLIMIT_NPROC] = {"Max processes", "processes"}, 406 [RLIMIT_NOFILE] = {"Max open files", "files"}, 407 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, 408 [RLIMIT_AS] = {"Max address space", "bytes"}, 409 [RLIMIT_LOCKS] = {"Max file locks", "locks"}, 410 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, 411 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, 412 [RLIMIT_NICE] = {"Max nice priority", NULL}, 413 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, 414 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, 415 }; 416 417 /* Display limits for a process */ 418 static int proc_pid_limits(struct task_struct *task, char *buffer) 419 { 420 unsigned int i; 421 int count = 0; 422 unsigned long flags; 423 char *bufptr = buffer; 424 425 struct rlimit rlim[RLIM_NLIMITS]; 426 427 rcu_read_lock(); 428 if (!lock_task_sighand(task,&flags)) { 429 rcu_read_unlock(); 430 return 0; 431 } 432 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); 433 unlock_task_sighand(task, &flags); 434 rcu_read_unlock(); 435 436 /* 437 * print the file header 438 */ 439 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n", 440 "Limit", "Soft Limit", "Hard Limit", "Units"); 441 442 for (i = 0; i < RLIM_NLIMITS; i++) { 443 if (rlim[i].rlim_cur == RLIM_INFINITY) 444 count += sprintf(&bufptr[count], "%-25s %-20s ", 445 lnames[i].name, "unlimited"); 446 else 447 count += sprintf(&bufptr[count], "%-25s %-20lu ", 448 lnames[i].name, rlim[i].rlim_cur); 449 450 if (rlim[i].rlim_max == RLIM_INFINITY) 451 count += sprintf(&bufptr[count], "%-20s ", "unlimited"); 452 else 453 count += sprintf(&bufptr[count], "%-20lu ", 454 rlim[i].rlim_max); 455 456 if (lnames[i].unit) 457 count += sprintf(&bufptr[count], "%-10s\n", 458 lnames[i].unit); 459 else 460 count += sprintf(&bufptr[count], "\n"); 461 } 462 463 return count; 464 } 465 466 /************************************************************************/ 467 /* Here the fs part begins */ 468 /************************************************************************/ 469 470 /* permission checks */ 471 static int proc_fd_access_allowed(struct inode *inode) 472 { 473 struct task_struct *task; 474 int allowed = 0; 475 /* Allow access to a task's file descriptors if it is us or we 476 * may use ptrace attach to the process and find out that 477 * information. 478 */ 479 task = get_proc_task(inode); 480 if (task) { 481 allowed = ptrace_may_attach(task); 482 put_task_struct(task); 483 } 484 return allowed; 485 } 486 487 static int proc_setattr(struct dentry *dentry, struct iattr *attr) 488 { 489 int error; 490 struct inode *inode = dentry->d_inode; 491 492 if (attr->ia_valid & ATTR_MODE) 493 return -EPERM; 494 495 error = inode_change_ok(inode, attr); 496 if (!error) 497 error = inode_setattr(inode, attr); 498 return error; 499 } 500 501 static const struct inode_operations proc_def_inode_operations = { 502 .setattr = proc_setattr, 503 }; 504 505 extern const struct seq_operations mounts_op; 506 struct proc_mounts { 507 struct seq_file m; 508 int event; 509 }; 510 511 static int mounts_open(struct inode *inode, struct file *file) 512 { 513 struct task_struct *task = get_proc_task(inode); 514 struct nsproxy *nsp; 515 struct mnt_namespace *ns = NULL; 516 struct proc_mounts *p; 517 int ret = -EINVAL; 518 519 if (task) { 520 rcu_read_lock(); 521 nsp = task_nsproxy(task); 522 if (nsp) { 523 ns = nsp->mnt_ns; 524 if (ns) 525 get_mnt_ns(ns); 526 } 527 rcu_read_unlock(); 528 529 put_task_struct(task); 530 } 531 532 if (ns) { 533 ret = -ENOMEM; 534 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); 535 if (p) { 536 file->private_data = &p->m; 537 ret = seq_open(file, &mounts_op); 538 if (!ret) { 539 p->m.private = ns; 540 p->event = ns->event; 541 return 0; 542 } 543 kfree(p); 544 } 545 put_mnt_ns(ns); 546 } 547 return ret; 548 } 549 550 static int mounts_release(struct inode *inode, struct file *file) 551 { 552 struct seq_file *m = file->private_data; 553 struct mnt_namespace *ns = m->private; 554 put_mnt_ns(ns); 555 return seq_release(inode, file); 556 } 557 558 static unsigned mounts_poll(struct file *file, poll_table *wait) 559 { 560 struct proc_mounts *p = file->private_data; 561 struct mnt_namespace *ns = p->m.private; 562 unsigned res = 0; 563 564 poll_wait(file, &ns->poll, wait); 565 566 spin_lock(&vfsmount_lock); 567 if (p->event != ns->event) { 568 p->event = ns->event; 569 res = POLLERR; 570 } 571 spin_unlock(&vfsmount_lock); 572 573 return res; 574 } 575 576 static const struct file_operations proc_mounts_operations = { 577 .open = mounts_open, 578 .read = seq_read, 579 .llseek = seq_lseek, 580 .release = mounts_release, 581 .poll = mounts_poll, 582 }; 583 584 extern const struct seq_operations mountstats_op; 585 static int mountstats_open(struct inode *inode, struct file *file) 586 { 587 int ret = seq_open(file, &mountstats_op); 588 589 if (!ret) { 590 struct seq_file *m = file->private_data; 591 struct nsproxy *nsp; 592 struct mnt_namespace *mnt_ns = NULL; 593 struct task_struct *task = get_proc_task(inode); 594 595 if (task) { 596 rcu_read_lock(); 597 nsp = task_nsproxy(task); 598 if (nsp) { 599 mnt_ns = nsp->mnt_ns; 600 if (mnt_ns) 601 get_mnt_ns(mnt_ns); 602 } 603 rcu_read_unlock(); 604 605 put_task_struct(task); 606 } 607 608 if (mnt_ns) 609 m->private = mnt_ns; 610 else { 611 seq_release(inode, file); 612 ret = -EINVAL; 613 } 614 } 615 return ret; 616 } 617 618 static const struct file_operations proc_mountstats_operations = { 619 .open = mountstats_open, 620 .read = seq_read, 621 .llseek = seq_lseek, 622 .release = mounts_release, 623 }; 624 625 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 626 627 static ssize_t proc_info_read(struct file * file, char __user * buf, 628 size_t count, loff_t *ppos) 629 { 630 struct inode * inode = file->f_path.dentry->d_inode; 631 unsigned long page; 632 ssize_t length; 633 struct task_struct *task = get_proc_task(inode); 634 635 length = -ESRCH; 636 if (!task) 637 goto out_no_task; 638 639 if (count > PROC_BLOCK_SIZE) 640 count = PROC_BLOCK_SIZE; 641 642 length = -ENOMEM; 643 if (!(page = __get_free_page(GFP_TEMPORARY))) 644 goto out; 645 646 length = PROC_I(inode)->op.proc_read(task, (char*)page); 647 648 if (length >= 0) 649 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 650 free_page(page); 651 out: 652 put_task_struct(task); 653 out_no_task: 654 return length; 655 } 656 657 static const struct file_operations proc_info_file_operations = { 658 .read = proc_info_read, 659 }; 660 661 static int proc_single_show(struct seq_file *m, void *v) 662 { 663 struct inode *inode = m->private; 664 struct pid_namespace *ns; 665 struct pid *pid; 666 struct task_struct *task; 667 int ret; 668 669 ns = inode->i_sb->s_fs_info; 670 pid = proc_pid(inode); 671 task = get_pid_task(pid, PIDTYPE_PID); 672 if (!task) 673 return -ESRCH; 674 675 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); 676 677 put_task_struct(task); 678 return ret; 679 } 680 681 static int proc_single_open(struct inode *inode, struct file *filp) 682 { 683 int ret; 684 ret = single_open(filp, proc_single_show, NULL); 685 if (!ret) { 686 struct seq_file *m = filp->private_data; 687 688 m->private = inode; 689 } 690 return ret; 691 } 692 693 static const struct file_operations proc_single_file_operations = { 694 .open = proc_single_open, 695 .read = seq_read, 696 .llseek = seq_lseek, 697 .release = single_release, 698 }; 699 700 static int mem_open(struct inode* inode, struct file* file) 701 { 702 file->private_data = (void*)((long)current->self_exec_id); 703 return 0; 704 } 705 706 static ssize_t mem_read(struct file * file, char __user * buf, 707 size_t count, loff_t *ppos) 708 { 709 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 710 char *page; 711 unsigned long src = *ppos; 712 int ret = -ESRCH; 713 struct mm_struct *mm; 714 715 if (!task) 716 goto out_no_task; 717 718 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 719 goto out; 720 721 ret = -ENOMEM; 722 page = (char *)__get_free_page(GFP_TEMPORARY); 723 if (!page) 724 goto out; 725 726 ret = 0; 727 728 mm = get_task_mm(task); 729 if (!mm) 730 goto out_free; 731 732 ret = -EIO; 733 734 if (file->private_data != (void*)((long)current->self_exec_id)) 735 goto out_put; 736 737 ret = 0; 738 739 while (count > 0) { 740 int this_len, retval; 741 742 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 743 retval = access_process_vm(task, src, page, this_len, 0); 744 if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) { 745 if (!ret) 746 ret = -EIO; 747 break; 748 } 749 750 if (copy_to_user(buf, page, retval)) { 751 ret = -EFAULT; 752 break; 753 } 754 755 ret += retval; 756 src += retval; 757 buf += retval; 758 count -= retval; 759 } 760 *ppos = src; 761 762 out_put: 763 mmput(mm); 764 out_free: 765 free_page((unsigned long) page); 766 out: 767 put_task_struct(task); 768 out_no_task: 769 return ret; 770 } 771 772 #define mem_write NULL 773 774 #ifndef mem_write 775 /* This is a security hazard */ 776 static ssize_t mem_write(struct file * file, const char __user *buf, 777 size_t count, loff_t *ppos) 778 { 779 int copied; 780 char *page; 781 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 782 unsigned long dst = *ppos; 783 784 copied = -ESRCH; 785 if (!task) 786 goto out_no_task; 787 788 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 789 goto out; 790 791 copied = -ENOMEM; 792 page = (char *)__get_free_page(GFP_TEMPORARY); 793 if (!page) 794 goto out; 795 796 copied = 0; 797 while (count > 0) { 798 int this_len, retval; 799 800 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 801 if (copy_from_user(page, buf, this_len)) { 802 copied = -EFAULT; 803 break; 804 } 805 retval = access_process_vm(task, dst, page, this_len, 1); 806 if (!retval) { 807 if (!copied) 808 copied = -EIO; 809 break; 810 } 811 copied += retval; 812 buf += retval; 813 dst += retval; 814 count -= retval; 815 } 816 *ppos = dst; 817 free_page((unsigned long) page); 818 out: 819 put_task_struct(task); 820 out_no_task: 821 return copied; 822 } 823 #endif 824 825 loff_t mem_lseek(struct file *file, loff_t offset, int orig) 826 { 827 switch (orig) { 828 case 0: 829 file->f_pos = offset; 830 break; 831 case 1: 832 file->f_pos += offset; 833 break; 834 default: 835 return -EINVAL; 836 } 837 force_successful_syscall_return(); 838 return file->f_pos; 839 } 840 841 static const struct file_operations proc_mem_operations = { 842 .llseek = mem_lseek, 843 .read = mem_read, 844 .write = mem_write, 845 .open = mem_open, 846 }; 847 848 static ssize_t environ_read(struct file *file, char __user *buf, 849 size_t count, loff_t *ppos) 850 { 851 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 852 char *page; 853 unsigned long src = *ppos; 854 int ret = -ESRCH; 855 struct mm_struct *mm; 856 857 if (!task) 858 goto out_no_task; 859 860 if (!ptrace_may_attach(task)) 861 goto out; 862 863 ret = -ENOMEM; 864 page = (char *)__get_free_page(GFP_TEMPORARY); 865 if (!page) 866 goto out; 867 868 ret = 0; 869 870 mm = get_task_mm(task); 871 if (!mm) 872 goto out_free; 873 874 while (count > 0) { 875 int this_len, retval, max_len; 876 877 this_len = mm->env_end - (mm->env_start + src); 878 879 if (this_len <= 0) 880 break; 881 882 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 883 this_len = (this_len > max_len) ? max_len : this_len; 884 885 retval = access_process_vm(task, (mm->env_start + src), 886 page, this_len, 0); 887 888 if (retval <= 0) { 889 ret = retval; 890 break; 891 } 892 893 if (copy_to_user(buf, page, retval)) { 894 ret = -EFAULT; 895 break; 896 } 897 898 ret += retval; 899 src += retval; 900 buf += retval; 901 count -= retval; 902 } 903 *ppos = src; 904 905 mmput(mm); 906 out_free: 907 free_page((unsigned long) page); 908 out: 909 put_task_struct(task); 910 out_no_task: 911 return ret; 912 } 913 914 static const struct file_operations proc_environ_operations = { 915 .read = environ_read, 916 }; 917 918 static ssize_t oom_adjust_read(struct file *file, char __user *buf, 919 size_t count, loff_t *ppos) 920 { 921 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 922 char buffer[PROC_NUMBUF]; 923 size_t len; 924 int oom_adjust; 925 926 if (!task) 927 return -ESRCH; 928 oom_adjust = task->oomkilladj; 929 put_task_struct(task); 930 931 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust); 932 933 return simple_read_from_buffer(buf, count, ppos, buffer, len); 934 } 935 936 static ssize_t oom_adjust_write(struct file *file, const char __user *buf, 937 size_t count, loff_t *ppos) 938 { 939 struct task_struct *task; 940 char buffer[PROC_NUMBUF], *end; 941 int oom_adjust; 942 943 memset(buffer, 0, sizeof(buffer)); 944 if (count > sizeof(buffer) - 1) 945 count = sizeof(buffer) - 1; 946 if (copy_from_user(buffer, buf, count)) 947 return -EFAULT; 948 oom_adjust = simple_strtol(buffer, &end, 0); 949 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) && 950 oom_adjust != OOM_DISABLE) 951 return -EINVAL; 952 if (*end == '\n') 953 end++; 954 task = get_proc_task(file->f_path.dentry->d_inode); 955 if (!task) 956 return -ESRCH; 957 if (oom_adjust < task->oomkilladj && !capable(CAP_SYS_RESOURCE)) { 958 put_task_struct(task); 959 return -EACCES; 960 } 961 task->oomkilladj = oom_adjust; 962 put_task_struct(task); 963 if (end - buffer == 0) 964 return -EIO; 965 return end - buffer; 966 } 967 968 static const struct file_operations proc_oom_adjust_operations = { 969 .read = oom_adjust_read, 970 .write = oom_adjust_write, 971 }; 972 973 #ifdef CONFIG_AUDITSYSCALL 974 #define TMPBUFLEN 21 975 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 976 size_t count, loff_t *ppos) 977 { 978 struct inode * inode = file->f_path.dentry->d_inode; 979 struct task_struct *task = get_proc_task(inode); 980 ssize_t length; 981 char tmpbuf[TMPBUFLEN]; 982 983 if (!task) 984 return -ESRCH; 985 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 986 audit_get_loginuid(task)); 987 put_task_struct(task); 988 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 989 } 990 991 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 992 size_t count, loff_t *ppos) 993 { 994 struct inode * inode = file->f_path.dentry->d_inode; 995 char *page, *tmp; 996 ssize_t length; 997 uid_t loginuid; 998 999 if (!capable(CAP_AUDIT_CONTROL)) 1000 return -EPERM; 1001 1002 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) 1003 return -EPERM; 1004 1005 if (count >= PAGE_SIZE) 1006 count = PAGE_SIZE - 1; 1007 1008 if (*ppos != 0) { 1009 /* No partial writes. */ 1010 return -EINVAL; 1011 } 1012 page = (char*)__get_free_page(GFP_TEMPORARY); 1013 if (!page) 1014 return -ENOMEM; 1015 length = -EFAULT; 1016 if (copy_from_user(page, buf, count)) 1017 goto out_free_page; 1018 1019 page[count] = '\0'; 1020 loginuid = simple_strtoul(page, &tmp, 10); 1021 if (tmp == page) { 1022 length = -EINVAL; 1023 goto out_free_page; 1024 1025 } 1026 length = audit_set_loginuid(current, loginuid); 1027 if (likely(length == 0)) 1028 length = count; 1029 1030 out_free_page: 1031 free_page((unsigned long) page); 1032 return length; 1033 } 1034 1035 static const struct file_operations proc_loginuid_operations = { 1036 .read = proc_loginuid_read, 1037 .write = proc_loginuid_write, 1038 }; 1039 1040 static ssize_t proc_sessionid_read(struct file * file, char __user * buf, 1041 size_t count, loff_t *ppos) 1042 { 1043 struct inode * inode = file->f_path.dentry->d_inode; 1044 struct task_struct *task = get_proc_task(inode); 1045 ssize_t length; 1046 char tmpbuf[TMPBUFLEN]; 1047 1048 if (!task) 1049 return -ESRCH; 1050 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 1051 audit_get_sessionid(task)); 1052 put_task_struct(task); 1053 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 1054 } 1055 1056 static const struct file_operations proc_sessionid_operations = { 1057 .read = proc_sessionid_read, 1058 }; 1059 #endif 1060 1061 #ifdef CONFIG_FAULT_INJECTION 1062 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, 1063 size_t count, loff_t *ppos) 1064 { 1065 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 1066 char buffer[PROC_NUMBUF]; 1067 size_t len; 1068 int make_it_fail; 1069 1070 if (!task) 1071 return -ESRCH; 1072 make_it_fail = task->make_it_fail; 1073 put_task_struct(task); 1074 1075 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); 1076 1077 return simple_read_from_buffer(buf, count, ppos, buffer, len); 1078 } 1079 1080 static ssize_t proc_fault_inject_write(struct file * file, 1081 const char __user * buf, size_t count, loff_t *ppos) 1082 { 1083 struct task_struct *task; 1084 char buffer[PROC_NUMBUF], *end; 1085 int make_it_fail; 1086 1087 if (!capable(CAP_SYS_RESOURCE)) 1088 return -EPERM; 1089 memset(buffer, 0, sizeof(buffer)); 1090 if (count > sizeof(buffer) - 1) 1091 count = sizeof(buffer) - 1; 1092 if (copy_from_user(buffer, buf, count)) 1093 return -EFAULT; 1094 make_it_fail = simple_strtol(buffer, &end, 0); 1095 if (*end == '\n') 1096 end++; 1097 task = get_proc_task(file->f_dentry->d_inode); 1098 if (!task) 1099 return -ESRCH; 1100 task->make_it_fail = make_it_fail; 1101 put_task_struct(task); 1102 if (end - buffer == 0) 1103 return -EIO; 1104 return end - buffer; 1105 } 1106 1107 static const struct file_operations proc_fault_inject_operations = { 1108 .read = proc_fault_inject_read, 1109 .write = proc_fault_inject_write, 1110 }; 1111 #endif 1112 1113 1114 #ifdef CONFIG_SCHED_DEBUG 1115 /* 1116 * Print out various scheduling related per-task fields: 1117 */ 1118 static int sched_show(struct seq_file *m, void *v) 1119 { 1120 struct inode *inode = m->private; 1121 struct task_struct *p; 1122 1123 WARN_ON(!inode); 1124 1125 p = get_proc_task(inode); 1126 if (!p) 1127 return -ESRCH; 1128 proc_sched_show_task(p, m); 1129 1130 put_task_struct(p); 1131 1132 return 0; 1133 } 1134 1135 static ssize_t 1136 sched_write(struct file *file, const char __user *buf, 1137 size_t count, loff_t *offset) 1138 { 1139 struct inode *inode = file->f_path.dentry->d_inode; 1140 struct task_struct *p; 1141 1142 WARN_ON(!inode); 1143 1144 p = get_proc_task(inode); 1145 if (!p) 1146 return -ESRCH; 1147 proc_sched_set_task(p); 1148 1149 put_task_struct(p); 1150 1151 return count; 1152 } 1153 1154 static int sched_open(struct inode *inode, struct file *filp) 1155 { 1156 int ret; 1157 1158 ret = single_open(filp, sched_show, NULL); 1159 if (!ret) { 1160 struct seq_file *m = filp->private_data; 1161 1162 m->private = inode; 1163 } 1164 return ret; 1165 } 1166 1167 static const struct file_operations proc_pid_sched_operations = { 1168 .open = sched_open, 1169 .read = seq_read, 1170 .write = sched_write, 1171 .llseek = seq_lseek, 1172 .release = single_release, 1173 }; 1174 1175 #endif 1176 1177 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1178 { 1179 struct inode *inode = dentry->d_inode; 1180 int error = -EACCES; 1181 1182 /* We don't need a base pointer in the /proc filesystem */ 1183 path_put(&nd->path); 1184 1185 /* Are we allowed to snoop on the tasks file descriptors? */ 1186 if (!proc_fd_access_allowed(inode)) 1187 goto out; 1188 1189 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path); 1190 nd->last_type = LAST_BIND; 1191 out: 1192 return ERR_PTR(error); 1193 } 1194 1195 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) 1196 { 1197 char *tmp = (char*)__get_free_page(GFP_TEMPORARY); 1198 char *pathname; 1199 int len; 1200 1201 if (!tmp) 1202 return -ENOMEM; 1203 1204 pathname = d_path(path, tmp, PAGE_SIZE); 1205 len = PTR_ERR(pathname); 1206 if (IS_ERR(pathname)) 1207 goto out; 1208 len = tmp + PAGE_SIZE - 1 - pathname; 1209 1210 if (len > buflen) 1211 len = buflen; 1212 if (copy_to_user(buffer, pathname, len)) 1213 len = -EFAULT; 1214 out: 1215 free_page((unsigned long)tmp); 1216 return len; 1217 } 1218 1219 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1220 { 1221 int error = -EACCES; 1222 struct inode *inode = dentry->d_inode; 1223 struct path path; 1224 1225 /* Are we allowed to snoop on the tasks file descriptors? */ 1226 if (!proc_fd_access_allowed(inode)) 1227 goto out; 1228 1229 error = PROC_I(inode)->op.proc_get_link(inode, &path); 1230 if (error) 1231 goto out; 1232 1233 error = do_proc_readlink(&path, buffer, buflen); 1234 path_put(&path); 1235 out: 1236 return error; 1237 } 1238 1239 static const struct inode_operations proc_pid_link_inode_operations = { 1240 .readlink = proc_pid_readlink, 1241 .follow_link = proc_pid_follow_link, 1242 .setattr = proc_setattr, 1243 }; 1244 1245 1246 /* building an inode */ 1247 1248 static int task_dumpable(struct task_struct *task) 1249 { 1250 int dumpable = 0; 1251 struct mm_struct *mm; 1252 1253 task_lock(task); 1254 mm = task->mm; 1255 if (mm) 1256 dumpable = get_dumpable(mm); 1257 task_unlock(task); 1258 if(dumpable == 1) 1259 return 1; 1260 return 0; 1261 } 1262 1263 1264 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) 1265 { 1266 struct inode * inode; 1267 struct proc_inode *ei; 1268 1269 /* We need a new inode */ 1270 1271 inode = new_inode(sb); 1272 if (!inode) 1273 goto out; 1274 1275 /* Common stuff */ 1276 ei = PROC_I(inode); 1277 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1278 inode->i_op = &proc_def_inode_operations; 1279 1280 /* 1281 * grab the reference to task. 1282 */ 1283 ei->pid = get_task_pid(task, PIDTYPE_PID); 1284 if (!ei->pid) 1285 goto out_unlock; 1286 1287 inode->i_uid = 0; 1288 inode->i_gid = 0; 1289 if (task_dumpable(task)) { 1290 inode->i_uid = task->euid; 1291 inode->i_gid = task->egid; 1292 } 1293 security_task_to_inode(task, inode); 1294 1295 out: 1296 return inode; 1297 1298 out_unlock: 1299 iput(inode); 1300 return NULL; 1301 } 1302 1303 static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 1304 { 1305 struct inode *inode = dentry->d_inode; 1306 struct task_struct *task; 1307 generic_fillattr(inode, stat); 1308 1309 rcu_read_lock(); 1310 stat->uid = 0; 1311 stat->gid = 0; 1312 task = pid_task(proc_pid(inode), PIDTYPE_PID); 1313 if (task) { 1314 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1315 task_dumpable(task)) { 1316 stat->uid = task->euid; 1317 stat->gid = task->egid; 1318 } 1319 } 1320 rcu_read_unlock(); 1321 return 0; 1322 } 1323 1324 /* dentry stuff */ 1325 1326 /* 1327 * Exceptional case: normally we are not allowed to unhash a busy 1328 * directory. In this case, however, we can do it - no aliasing problems 1329 * due to the way we treat inodes. 1330 * 1331 * Rewrite the inode's ownerships here because the owning task may have 1332 * performed a setuid(), etc. 1333 * 1334 * Before the /proc/pid/status file was created the only way to read 1335 * the effective uid of a /process was to stat /proc/pid. Reading 1336 * /proc/pid/status is slow enough that procps and other packages 1337 * kept stating /proc/pid. To keep the rules in /proc simple I have 1338 * made this apply to all per process world readable and executable 1339 * directories. 1340 */ 1341 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) 1342 { 1343 struct inode *inode = dentry->d_inode; 1344 struct task_struct *task = get_proc_task(inode); 1345 if (task) { 1346 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || 1347 task_dumpable(task)) { 1348 inode->i_uid = task->euid; 1349 inode->i_gid = task->egid; 1350 } else { 1351 inode->i_uid = 0; 1352 inode->i_gid = 0; 1353 } 1354 inode->i_mode &= ~(S_ISUID | S_ISGID); 1355 security_task_to_inode(task, inode); 1356 put_task_struct(task); 1357 return 1; 1358 } 1359 d_drop(dentry); 1360 return 0; 1361 } 1362 1363 static int pid_delete_dentry(struct dentry * dentry) 1364 { 1365 /* Is the task we represent dead? 1366 * If so, then don't put the dentry on the lru list, 1367 * kill it immediately. 1368 */ 1369 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first; 1370 } 1371 1372 static struct dentry_operations pid_dentry_operations = 1373 { 1374 .d_revalidate = pid_revalidate, 1375 .d_delete = pid_delete_dentry, 1376 }; 1377 1378 /* Lookups */ 1379 1380 typedef struct dentry *instantiate_t(struct inode *, struct dentry *, 1381 struct task_struct *, const void *); 1382 1383 /* 1384 * Fill a directory entry. 1385 * 1386 * If possible create the dcache entry and derive our inode number and 1387 * file type from dcache entry. 1388 * 1389 * Since all of the proc inode numbers are dynamically generated, the inode 1390 * numbers do not exist until the inode is cache. This means creating the 1391 * the dcache entry in readdir is necessary to keep the inode numbers 1392 * reported by readdir in sync with the inode numbers reported 1393 * by stat. 1394 */ 1395 static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 1396 char *name, int len, 1397 instantiate_t instantiate, struct task_struct *task, const void *ptr) 1398 { 1399 struct dentry *child, *dir = filp->f_path.dentry; 1400 struct inode *inode; 1401 struct qstr qname; 1402 ino_t ino = 0; 1403 unsigned type = DT_UNKNOWN; 1404 1405 qname.name = name; 1406 qname.len = len; 1407 qname.hash = full_name_hash(name, len); 1408 1409 child = d_lookup(dir, &qname); 1410 if (!child) { 1411 struct dentry *new; 1412 new = d_alloc(dir, &qname); 1413 if (new) { 1414 child = instantiate(dir->d_inode, new, task, ptr); 1415 if (child) 1416 dput(new); 1417 else 1418 child = new; 1419 } 1420 } 1421 if (!child || IS_ERR(child) || !child->d_inode) 1422 goto end_instantiate; 1423 inode = child->d_inode; 1424 if (inode) { 1425 ino = inode->i_ino; 1426 type = inode->i_mode >> 12; 1427 } 1428 dput(child); 1429 end_instantiate: 1430 if (!ino) 1431 ino = find_inode_number(dir, &qname); 1432 if (!ino) 1433 ino = 1; 1434 return filldir(dirent, name, len, filp->f_pos, ino, type); 1435 } 1436 1437 static unsigned name_to_int(struct dentry *dentry) 1438 { 1439 const char *name = dentry->d_name.name; 1440 int len = dentry->d_name.len; 1441 unsigned n = 0; 1442 1443 if (len > 1 && *name == '0') 1444 goto out; 1445 while (len-- > 0) { 1446 unsigned c = *name++ - '0'; 1447 if (c > 9) 1448 goto out; 1449 if (n >= (~0U-9)/10) 1450 goto out; 1451 n *= 10; 1452 n += c; 1453 } 1454 return n; 1455 out: 1456 return ~0U; 1457 } 1458 1459 #define PROC_FDINFO_MAX 64 1460 1461 static int proc_fd_info(struct inode *inode, struct path *path, char *info) 1462 { 1463 struct task_struct *task = get_proc_task(inode); 1464 struct files_struct *files = NULL; 1465 struct file *file; 1466 int fd = proc_fd(inode); 1467 1468 if (task) { 1469 files = get_files_struct(task); 1470 put_task_struct(task); 1471 } 1472 if (files) { 1473 /* 1474 * We are not taking a ref to the file structure, so we must 1475 * hold ->file_lock. 1476 */ 1477 spin_lock(&files->file_lock); 1478 file = fcheck_files(files, fd); 1479 if (file) { 1480 if (path) { 1481 *path = file->f_path; 1482 path_get(&file->f_path); 1483 } 1484 if (info) 1485 snprintf(info, PROC_FDINFO_MAX, 1486 "pos:\t%lli\n" 1487 "flags:\t0%o\n", 1488 (long long) file->f_pos, 1489 file->f_flags); 1490 spin_unlock(&files->file_lock); 1491 put_files_struct(files); 1492 return 0; 1493 } 1494 spin_unlock(&files->file_lock); 1495 put_files_struct(files); 1496 } 1497 return -ENOENT; 1498 } 1499 1500 static int proc_fd_link(struct inode *inode, struct path *path) 1501 { 1502 return proc_fd_info(inode, path, NULL); 1503 } 1504 1505 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) 1506 { 1507 struct inode *inode = dentry->d_inode; 1508 struct task_struct *task = get_proc_task(inode); 1509 int fd = proc_fd(inode); 1510 struct files_struct *files; 1511 1512 if (task) { 1513 files = get_files_struct(task); 1514 if (files) { 1515 rcu_read_lock(); 1516 if (fcheck_files(files, fd)) { 1517 rcu_read_unlock(); 1518 put_files_struct(files); 1519 if (task_dumpable(task)) { 1520 inode->i_uid = task->euid; 1521 inode->i_gid = task->egid; 1522 } else { 1523 inode->i_uid = 0; 1524 inode->i_gid = 0; 1525 } 1526 inode->i_mode &= ~(S_ISUID | S_ISGID); 1527 security_task_to_inode(task, inode); 1528 put_task_struct(task); 1529 return 1; 1530 } 1531 rcu_read_unlock(); 1532 put_files_struct(files); 1533 } 1534 put_task_struct(task); 1535 } 1536 d_drop(dentry); 1537 return 0; 1538 } 1539 1540 static struct dentry_operations tid_fd_dentry_operations = 1541 { 1542 .d_revalidate = tid_fd_revalidate, 1543 .d_delete = pid_delete_dentry, 1544 }; 1545 1546 static struct dentry *proc_fd_instantiate(struct inode *dir, 1547 struct dentry *dentry, struct task_struct *task, const void *ptr) 1548 { 1549 unsigned fd = *(const unsigned *)ptr; 1550 struct file *file; 1551 struct files_struct *files; 1552 struct inode *inode; 1553 struct proc_inode *ei; 1554 struct dentry *error = ERR_PTR(-ENOENT); 1555 1556 inode = proc_pid_make_inode(dir->i_sb, task); 1557 if (!inode) 1558 goto out; 1559 ei = PROC_I(inode); 1560 ei->fd = fd; 1561 files = get_files_struct(task); 1562 if (!files) 1563 goto out_iput; 1564 inode->i_mode = S_IFLNK; 1565 1566 /* 1567 * We are not taking a ref to the file structure, so we must 1568 * hold ->file_lock. 1569 */ 1570 spin_lock(&files->file_lock); 1571 file = fcheck_files(files, fd); 1572 if (!file) 1573 goto out_unlock; 1574 if (file->f_mode & 1) 1575 inode->i_mode |= S_IRUSR | S_IXUSR; 1576 if (file->f_mode & 2) 1577 inode->i_mode |= S_IWUSR | S_IXUSR; 1578 spin_unlock(&files->file_lock); 1579 put_files_struct(files); 1580 1581 inode->i_op = &proc_pid_link_inode_operations; 1582 inode->i_size = 64; 1583 ei->op.proc_get_link = proc_fd_link; 1584 dentry->d_op = &tid_fd_dentry_operations; 1585 d_add(dentry, inode); 1586 /* Close the race of the process dying before we return the dentry */ 1587 if (tid_fd_revalidate(dentry, NULL)) 1588 error = NULL; 1589 1590 out: 1591 return error; 1592 out_unlock: 1593 spin_unlock(&files->file_lock); 1594 put_files_struct(files); 1595 out_iput: 1596 iput(inode); 1597 goto out; 1598 } 1599 1600 static struct dentry *proc_lookupfd_common(struct inode *dir, 1601 struct dentry *dentry, 1602 instantiate_t instantiate) 1603 { 1604 struct task_struct *task = get_proc_task(dir); 1605 unsigned fd = name_to_int(dentry); 1606 struct dentry *result = ERR_PTR(-ENOENT); 1607 1608 if (!task) 1609 goto out_no_task; 1610 if (fd == ~0U) 1611 goto out; 1612 1613 result = instantiate(dir, dentry, task, &fd); 1614 out: 1615 put_task_struct(task); 1616 out_no_task: 1617 return result; 1618 } 1619 1620 static int proc_readfd_common(struct file * filp, void * dirent, 1621 filldir_t filldir, instantiate_t instantiate) 1622 { 1623 struct dentry *dentry = filp->f_path.dentry; 1624 struct inode *inode = dentry->d_inode; 1625 struct task_struct *p = get_proc_task(inode); 1626 unsigned int fd, ino; 1627 int retval; 1628 struct files_struct * files; 1629 struct fdtable *fdt; 1630 1631 retval = -ENOENT; 1632 if (!p) 1633 goto out_no_task; 1634 retval = 0; 1635 1636 fd = filp->f_pos; 1637 switch (fd) { 1638 case 0: 1639 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) 1640 goto out; 1641 filp->f_pos++; 1642 case 1: 1643 ino = parent_ino(dentry); 1644 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1645 goto out; 1646 filp->f_pos++; 1647 default: 1648 files = get_files_struct(p); 1649 if (!files) 1650 goto out; 1651 rcu_read_lock(); 1652 fdt = files_fdtable(files); 1653 for (fd = filp->f_pos-2; 1654 fd < fdt->max_fds; 1655 fd++, filp->f_pos++) { 1656 char name[PROC_NUMBUF]; 1657 int len; 1658 1659 if (!fcheck_files(files, fd)) 1660 continue; 1661 rcu_read_unlock(); 1662 1663 len = snprintf(name, sizeof(name), "%d", fd); 1664 if (proc_fill_cache(filp, dirent, filldir, 1665 name, len, instantiate, 1666 p, &fd) < 0) { 1667 rcu_read_lock(); 1668 break; 1669 } 1670 rcu_read_lock(); 1671 } 1672 rcu_read_unlock(); 1673 put_files_struct(files); 1674 } 1675 out: 1676 put_task_struct(p); 1677 out_no_task: 1678 return retval; 1679 } 1680 1681 static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry, 1682 struct nameidata *nd) 1683 { 1684 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate); 1685 } 1686 1687 static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir) 1688 { 1689 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate); 1690 } 1691 1692 static ssize_t proc_fdinfo_read(struct file *file, char __user *buf, 1693 size_t len, loff_t *ppos) 1694 { 1695 char tmp[PROC_FDINFO_MAX]; 1696 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp); 1697 if (!err) 1698 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp)); 1699 return err; 1700 } 1701 1702 static const struct file_operations proc_fdinfo_file_operations = { 1703 .open = nonseekable_open, 1704 .read = proc_fdinfo_read, 1705 }; 1706 1707 static const struct file_operations proc_fd_operations = { 1708 .read = generic_read_dir, 1709 .readdir = proc_readfd, 1710 }; 1711 1712 /* 1713 * /proc/pid/fd needs a special permission handler so that a process can still 1714 * access /proc/self/fd after it has executed a setuid(). 1715 */ 1716 static int proc_fd_permission(struct inode *inode, int mask, 1717 struct nameidata *nd) 1718 { 1719 int rv; 1720 1721 rv = generic_permission(inode, mask, NULL); 1722 if (rv == 0) 1723 return 0; 1724 if (task_pid(current) == proc_pid(inode)) 1725 rv = 0; 1726 return rv; 1727 } 1728 1729 /* 1730 * proc directories can do almost nothing.. 1731 */ 1732 static const struct inode_operations proc_fd_inode_operations = { 1733 .lookup = proc_lookupfd, 1734 .permission = proc_fd_permission, 1735 .setattr = proc_setattr, 1736 }; 1737 1738 static struct dentry *proc_fdinfo_instantiate(struct inode *dir, 1739 struct dentry *dentry, struct task_struct *task, const void *ptr) 1740 { 1741 unsigned fd = *(unsigned *)ptr; 1742 struct inode *inode; 1743 struct proc_inode *ei; 1744 struct dentry *error = ERR_PTR(-ENOENT); 1745 1746 inode = proc_pid_make_inode(dir->i_sb, task); 1747 if (!inode) 1748 goto out; 1749 ei = PROC_I(inode); 1750 ei->fd = fd; 1751 inode->i_mode = S_IFREG | S_IRUSR; 1752 inode->i_fop = &proc_fdinfo_file_operations; 1753 dentry->d_op = &tid_fd_dentry_operations; 1754 d_add(dentry, inode); 1755 /* Close the race of the process dying before we return the dentry */ 1756 if (tid_fd_revalidate(dentry, NULL)) 1757 error = NULL; 1758 1759 out: 1760 return error; 1761 } 1762 1763 static struct dentry *proc_lookupfdinfo(struct inode *dir, 1764 struct dentry *dentry, 1765 struct nameidata *nd) 1766 { 1767 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate); 1768 } 1769 1770 static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir) 1771 { 1772 return proc_readfd_common(filp, dirent, filldir, 1773 proc_fdinfo_instantiate); 1774 } 1775 1776 static const struct file_operations proc_fdinfo_operations = { 1777 .read = generic_read_dir, 1778 .readdir = proc_readfdinfo, 1779 }; 1780 1781 /* 1782 * proc directories can do almost nothing.. 1783 */ 1784 static const struct inode_operations proc_fdinfo_inode_operations = { 1785 .lookup = proc_lookupfdinfo, 1786 .setattr = proc_setattr, 1787 }; 1788 1789 1790 static struct dentry *proc_pident_instantiate(struct inode *dir, 1791 struct dentry *dentry, struct task_struct *task, const void *ptr) 1792 { 1793 const struct pid_entry *p = ptr; 1794 struct inode *inode; 1795 struct proc_inode *ei; 1796 struct dentry *error = ERR_PTR(-EINVAL); 1797 1798 inode = proc_pid_make_inode(dir->i_sb, task); 1799 if (!inode) 1800 goto out; 1801 1802 ei = PROC_I(inode); 1803 inode->i_mode = p->mode; 1804 if (S_ISDIR(inode->i_mode)) 1805 inode->i_nlink = 2; /* Use getattr to fix if necessary */ 1806 if (p->iop) 1807 inode->i_op = p->iop; 1808 if (p->fop) 1809 inode->i_fop = p->fop; 1810 ei->op = p->op; 1811 dentry->d_op = &pid_dentry_operations; 1812 d_add(dentry, inode); 1813 /* Close the race of the process dying before we return the dentry */ 1814 if (pid_revalidate(dentry, NULL)) 1815 error = NULL; 1816 out: 1817 return error; 1818 } 1819 1820 static struct dentry *proc_pident_lookup(struct inode *dir, 1821 struct dentry *dentry, 1822 const struct pid_entry *ents, 1823 unsigned int nents) 1824 { 1825 struct inode *inode; 1826 struct dentry *error; 1827 struct task_struct *task = get_proc_task(dir); 1828 const struct pid_entry *p, *last; 1829 1830 error = ERR_PTR(-ENOENT); 1831 inode = NULL; 1832 1833 if (!task) 1834 goto out_no_task; 1835 1836 /* 1837 * Yes, it does not scale. And it should not. Don't add 1838 * new entries into /proc/<tgid>/ without very good reasons. 1839 */ 1840 last = &ents[nents - 1]; 1841 for (p = ents; p <= last; p++) { 1842 if (p->len != dentry->d_name.len) 1843 continue; 1844 if (!memcmp(dentry->d_name.name, p->name, p->len)) 1845 break; 1846 } 1847 if (p > last) 1848 goto out; 1849 1850 error = proc_pident_instantiate(dir, dentry, task, p); 1851 out: 1852 put_task_struct(task); 1853 out_no_task: 1854 return error; 1855 } 1856 1857 static int proc_pident_fill_cache(struct file *filp, void *dirent, 1858 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 1859 { 1860 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 1861 proc_pident_instantiate, task, p); 1862 } 1863 1864 static int proc_pident_readdir(struct file *filp, 1865 void *dirent, filldir_t filldir, 1866 const struct pid_entry *ents, unsigned int nents) 1867 { 1868 int i; 1869 struct dentry *dentry = filp->f_path.dentry; 1870 struct inode *inode = dentry->d_inode; 1871 struct task_struct *task = get_proc_task(inode); 1872 const struct pid_entry *p, *last; 1873 ino_t ino; 1874 int ret; 1875 1876 ret = -ENOENT; 1877 if (!task) 1878 goto out_no_task; 1879 1880 ret = 0; 1881 i = filp->f_pos; 1882 switch (i) { 1883 case 0: 1884 ino = inode->i_ino; 1885 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 1886 goto out; 1887 i++; 1888 filp->f_pos++; 1889 /* fall through */ 1890 case 1: 1891 ino = parent_ino(dentry); 1892 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 1893 goto out; 1894 i++; 1895 filp->f_pos++; 1896 /* fall through */ 1897 default: 1898 i -= 2; 1899 if (i >= nents) { 1900 ret = 1; 1901 goto out; 1902 } 1903 p = ents + i; 1904 last = &ents[nents - 1]; 1905 while (p <= last) { 1906 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) 1907 goto out; 1908 filp->f_pos++; 1909 p++; 1910 } 1911 } 1912 1913 ret = 1; 1914 out: 1915 put_task_struct(task); 1916 out_no_task: 1917 return ret; 1918 } 1919 1920 #ifdef CONFIG_SECURITY 1921 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 1922 size_t count, loff_t *ppos) 1923 { 1924 struct inode * inode = file->f_path.dentry->d_inode; 1925 char *p = NULL; 1926 ssize_t length; 1927 struct task_struct *task = get_proc_task(inode); 1928 1929 if (!task) 1930 return -ESRCH; 1931 1932 length = security_getprocattr(task, 1933 (char*)file->f_path.dentry->d_name.name, 1934 &p); 1935 put_task_struct(task); 1936 if (length > 0) 1937 length = simple_read_from_buffer(buf, count, ppos, p, length); 1938 kfree(p); 1939 return length; 1940 } 1941 1942 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 1943 size_t count, loff_t *ppos) 1944 { 1945 struct inode * inode = file->f_path.dentry->d_inode; 1946 char *page; 1947 ssize_t length; 1948 struct task_struct *task = get_proc_task(inode); 1949 1950 length = -ESRCH; 1951 if (!task) 1952 goto out_no_task; 1953 if (count > PAGE_SIZE) 1954 count = PAGE_SIZE; 1955 1956 /* No partial writes. */ 1957 length = -EINVAL; 1958 if (*ppos != 0) 1959 goto out; 1960 1961 length = -ENOMEM; 1962 page = (char*)__get_free_page(GFP_TEMPORARY); 1963 if (!page) 1964 goto out; 1965 1966 length = -EFAULT; 1967 if (copy_from_user(page, buf, count)) 1968 goto out_free; 1969 1970 length = security_setprocattr(task, 1971 (char*)file->f_path.dentry->d_name.name, 1972 (void*)page, count); 1973 out_free: 1974 free_page((unsigned long) page); 1975 out: 1976 put_task_struct(task); 1977 out_no_task: 1978 return length; 1979 } 1980 1981 static const struct file_operations proc_pid_attr_operations = { 1982 .read = proc_pid_attr_read, 1983 .write = proc_pid_attr_write, 1984 }; 1985 1986 static const struct pid_entry attr_dir_stuff[] = { 1987 REG("current", S_IRUGO|S_IWUGO, pid_attr), 1988 REG("prev", S_IRUGO, pid_attr), 1989 REG("exec", S_IRUGO|S_IWUGO, pid_attr), 1990 REG("fscreate", S_IRUGO|S_IWUGO, pid_attr), 1991 REG("keycreate", S_IRUGO|S_IWUGO, pid_attr), 1992 REG("sockcreate", S_IRUGO|S_IWUGO, pid_attr), 1993 }; 1994 1995 static int proc_attr_dir_readdir(struct file * filp, 1996 void * dirent, filldir_t filldir) 1997 { 1998 return proc_pident_readdir(filp,dirent,filldir, 1999 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); 2000 } 2001 2002 static const struct file_operations proc_attr_dir_operations = { 2003 .read = generic_read_dir, 2004 .readdir = proc_attr_dir_readdir, 2005 }; 2006 2007 static struct dentry *proc_attr_dir_lookup(struct inode *dir, 2008 struct dentry *dentry, struct nameidata *nd) 2009 { 2010 return proc_pident_lookup(dir, dentry, 2011 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); 2012 } 2013 2014 static const struct inode_operations proc_attr_dir_inode_operations = { 2015 .lookup = proc_attr_dir_lookup, 2016 .getattr = pid_getattr, 2017 .setattr = proc_setattr, 2018 }; 2019 2020 #endif 2021 2022 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE) 2023 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, 2024 size_t count, loff_t *ppos) 2025 { 2026 struct task_struct *task = get_proc_task(file->f_dentry->d_inode); 2027 struct mm_struct *mm; 2028 char buffer[PROC_NUMBUF]; 2029 size_t len; 2030 int ret; 2031 2032 if (!task) 2033 return -ESRCH; 2034 2035 ret = 0; 2036 mm = get_task_mm(task); 2037 if (mm) { 2038 len = snprintf(buffer, sizeof(buffer), "%08lx\n", 2039 ((mm->flags & MMF_DUMP_FILTER_MASK) >> 2040 MMF_DUMP_FILTER_SHIFT)); 2041 mmput(mm); 2042 ret = simple_read_from_buffer(buf, count, ppos, buffer, len); 2043 } 2044 2045 put_task_struct(task); 2046 2047 return ret; 2048 } 2049 2050 static ssize_t proc_coredump_filter_write(struct file *file, 2051 const char __user *buf, 2052 size_t count, 2053 loff_t *ppos) 2054 { 2055 struct task_struct *task; 2056 struct mm_struct *mm; 2057 char buffer[PROC_NUMBUF], *end; 2058 unsigned int val; 2059 int ret; 2060 int i; 2061 unsigned long mask; 2062 2063 ret = -EFAULT; 2064 memset(buffer, 0, sizeof(buffer)); 2065 if (count > sizeof(buffer) - 1) 2066 count = sizeof(buffer) - 1; 2067 if (copy_from_user(buffer, buf, count)) 2068 goto out_no_task; 2069 2070 ret = -EINVAL; 2071 val = (unsigned int)simple_strtoul(buffer, &end, 0); 2072 if (*end == '\n') 2073 end++; 2074 if (end - buffer == 0) 2075 goto out_no_task; 2076 2077 ret = -ESRCH; 2078 task = get_proc_task(file->f_dentry->d_inode); 2079 if (!task) 2080 goto out_no_task; 2081 2082 ret = end - buffer; 2083 mm = get_task_mm(task); 2084 if (!mm) 2085 goto out_no_mm; 2086 2087 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { 2088 if (val & mask) 2089 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2090 else 2091 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); 2092 } 2093 2094 mmput(mm); 2095 out_no_mm: 2096 put_task_struct(task); 2097 out_no_task: 2098 return ret; 2099 } 2100 2101 static const struct file_operations proc_coredump_filter_operations = { 2102 .read = proc_coredump_filter_read, 2103 .write = proc_coredump_filter_write, 2104 }; 2105 #endif 2106 2107 /* 2108 * /proc/self: 2109 */ 2110 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 2111 int buflen) 2112 { 2113 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2114 pid_t tgid = task_tgid_nr_ns(current, ns); 2115 char tmp[PROC_NUMBUF]; 2116 if (!tgid) 2117 return -ENOENT; 2118 sprintf(tmp, "%d", tgid); 2119 return vfs_readlink(dentry,buffer,buflen,tmp); 2120 } 2121 2122 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 2123 { 2124 struct pid_namespace *ns = dentry->d_sb->s_fs_info; 2125 pid_t tgid = task_tgid_nr_ns(current, ns); 2126 char tmp[PROC_NUMBUF]; 2127 if (!tgid) 2128 return ERR_PTR(-ENOENT); 2129 sprintf(tmp, "%d", task_tgid_nr_ns(current, ns)); 2130 return ERR_PTR(vfs_follow_link(nd,tmp)); 2131 } 2132 2133 static const struct inode_operations proc_self_inode_operations = { 2134 .readlink = proc_self_readlink, 2135 .follow_link = proc_self_follow_link, 2136 }; 2137 2138 /* 2139 * proc base 2140 * 2141 * These are the directory entries in the root directory of /proc 2142 * that properly belong to the /proc filesystem, as they describe 2143 * describe something that is process related. 2144 */ 2145 static const struct pid_entry proc_base_stuff[] = { 2146 NOD("self", S_IFLNK|S_IRWXUGO, 2147 &proc_self_inode_operations, NULL, {}), 2148 }; 2149 2150 /* 2151 * Exceptional case: normally we are not allowed to unhash a busy 2152 * directory. In this case, however, we can do it - no aliasing problems 2153 * due to the way we treat inodes. 2154 */ 2155 static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd) 2156 { 2157 struct inode *inode = dentry->d_inode; 2158 struct task_struct *task = get_proc_task(inode); 2159 if (task) { 2160 put_task_struct(task); 2161 return 1; 2162 } 2163 d_drop(dentry); 2164 return 0; 2165 } 2166 2167 static struct dentry_operations proc_base_dentry_operations = 2168 { 2169 .d_revalidate = proc_base_revalidate, 2170 .d_delete = pid_delete_dentry, 2171 }; 2172 2173 static struct dentry *proc_base_instantiate(struct inode *dir, 2174 struct dentry *dentry, struct task_struct *task, const void *ptr) 2175 { 2176 const struct pid_entry *p = ptr; 2177 struct inode *inode; 2178 struct proc_inode *ei; 2179 struct dentry *error = ERR_PTR(-EINVAL); 2180 2181 /* Allocate the inode */ 2182 error = ERR_PTR(-ENOMEM); 2183 inode = new_inode(dir->i_sb); 2184 if (!inode) 2185 goto out; 2186 2187 /* Initialize the inode */ 2188 ei = PROC_I(inode); 2189 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 2190 2191 /* 2192 * grab the reference to the task. 2193 */ 2194 ei->pid = get_task_pid(task, PIDTYPE_PID); 2195 if (!ei->pid) 2196 goto out_iput; 2197 2198 inode->i_uid = 0; 2199 inode->i_gid = 0; 2200 inode->i_mode = p->mode; 2201 if (S_ISDIR(inode->i_mode)) 2202 inode->i_nlink = 2; 2203 if (S_ISLNK(inode->i_mode)) 2204 inode->i_size = 64; 2205 if (p->iop) 2206 inode->i_op = p->iop; 2207 if (p->fop) 2208 inode->i_fop = p->fop; 2209 ei->op = p->op; 2210 dentry->d_op = &proc_base_dentry_operations; 2211 d_add(dentry, inode); 2212 error = NULL; 2213 out: 2214 return error; 2215 out_iput: 2216 iput(inode); 2217 goto out; 2218 } 2219 2220 static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) 2221 { 2222 struct dentry *error; 2223 struct task_struct *task = get_proc_task(dir); 2224 const struct pid_entry *p, *last; 2225 2226 error = ERR_PTR(-ENOENT); 2227 2228 if (!task) 2229 goto out_no_task; 2230 2231 /* Lookup the directory entry */ 2232 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1]; 2233 for (p = proc_base_stuff; p <= last; p++) { 2234 if (p->len != dentry->d_name.len) 2235 continue; 2236 if (!memcmp(dentry->d_name.name, p->name, p->len)) 2237 break; 2238 } 2239 if (p > last) 2240 goto out; 2241 2242 error = proc_base_instantiate(dir, dentry, task, p); 2243 2244 out: 2245 put_task_struct(task); 2246 out_no_task: 2247 return error; 2248 } 2249 2250 static int proc_base_fill_cache(struct file *filp, void *dirent, 2251 filldir_t filldir, struct task_struct *task, const struct pid_entry *p) 2252 { 2253 return proc_fill_cache(filp, dirent, filldir, p->name, p->len, 2254 proc_base_instantiate, task, p); 2255 } 2256 2257 #ifdef CONFIG_TASK_IO_ACCOUNTING 2258 static int proc_pid_io_accounting(struct task_struct *task, char *buffer) 2259 { 2260 return sprintf(buffer, 2261 #ifdef CONFIG_TASK_XACCT 2262 "rchar: %llu\n" 2263 "wchar: %llu\n" 2264 "syscr: %llu\n" 2265 "syscw: %llu\n" 2266 #endif 2267 "read_bytes: %llu\n" 2268 "write_bytes: %llu\n" 2269 "cancelled_write_bytes: %llu\n", 2270 #ifdef CONFIG_TASK_XACCT 2271 (unsigned long long)task->rchar, 2272 (unsigned long long)task->wchar, 2273 (unsigned long long)task->syscr, 2274 (unsigned long long)task->syscw, 2275 #endif 2276 (unsigned long long)task->ioac.read_bytes, 2277 (unsigned long long)task->ioac.write_bytes, 2278 (unsigned long long)task->ioac.cancelled_write_bytes); 2279 } 2280 #endif 2281 2282 /* 2283 * Thread groups 2284 */ 2285 static const struct file_operations proc_task_operations; 2286 static const struct inode_operations proc_task_inode_operations; 2287 2288 static const struct pid_entry tgid_base_stuff[] = { 2289 DIR("task", S_IRUGO|S_IXUGO, task), 2290 DIR("fd", S_IRUSR|S_IXUSR, fd), 2291 DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo), 2292 #ifdef CONFIG_NET 2293 DIR("net", S_IRUGO|S_IXUGO, net), 2294 #endif 2295 REG("environ", S_IRUSR, environ), 2296 INF("auxv", S_IRUSR, pid_auxv), 2297 ONE("status", S_IRUGO, pid_status), 2298 INF("limits", S_IRUSR, pid_limits), 2299 #ifdef CONFIG_SCHED_DEBUG 2300 REG("sched", S_IRUGO|S_IWUSR, pid_sched), 2301 #endif 2302 INF("cmdline", S_IRUGO, pid_cmdline), 2303 ONE("stat", S_IRUGO, tgid_stat), 2304 ONE("statm", S_IRUGO, pid_statm), 2305 REG("maps", S_IRUGO, maps), 2306 #ifdef CONFIG_NUMA 2307 REG("numa_maps", S_IRUGO, numa_maps), 2308 #endif 2309 REG("mem", S_IRUSR|S_IWUSR, mem), 2310 LNK("cwd", cwd), 2311 LNK("root", root), 2312 LNK("exe", exe), 2313 REG("mounts", S_IRUGO, mounts), 2314 REG("mountstats", S_IRUSR, mountstats), 2315 #ifdef CONFIG_PROC_PAGE_MONITOR 2316 REG("clear_refs", S_IWUSR, clear_refs), 2317 REG("smaps", S_IRUGO, smaps), 2318 REG("pagemap", S_IRUSR, pagemap), 2319 #endif 2320 #ifdef CONFIG_SECURITY 2321 DIR("attr", S_IRUGO|S_IXUGO, attr_dir), 2322 #endif 2323 #ifdef CONFIG_KALLSYMS 2324 INF("wchan", S_IRUGO, pid_wchan), 2325 #endif 2326 #ifdef CONFIG_SCHEDSTATS 2327 INF("schedstat", S_IRUGO, pid_schedstat), 2328 #endif 2329 #ifdef CONFIG_LATENCYTOP 2330 REG("latency", S_IRUGO, lstats), 2331 #endif 2332 #ifdef CONFIG_PROC_PID_CPUSET 2333 REG("cpuset", S_IRUGO, cpuset), 2334 #endif 2335 #ifdef CONFIG_CGROUPS 2336 REG("cgroup", S_IRUGO, cgroup), 2337 #endif 2338 INF("oom_score", S_IRUGO, oom_score), 2339 REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust), 2340 #ifdef CONFIG_AUDITSYSCALL 2341 REG("loginuid", S_IWUSR|S_IRUGO, loginuid), 2342 REG("sessionid", S_IRUSR, sessionid), 2343 #endif 2344 #ifdef CONFIG_FAULT_INJECTION 2345 REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject), 2346 #endif 2347 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE) 2348 REG("coredump_filter", S_IRUGO|S_IWUSR, coredump_filter), 2349 #endif 2350 #ifdef CONFIG_TASK_IO_ACCOUNTING 2351 INF("io", S_IRUGO, pid_io_accounting), 2352 #endif 2353 }; 2354 2355 static int proc_tgid_base_readdir(struct file * filp, 2356 void * dirent, filldir_t filldir) 2357 { 2358 return proc_pident_readdir(filp,dirent,filldir, 2359 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 2360 } 2361 2362 static const struct file_operations proc_tgid_base_operations = { 2363 .read = generic_read_dir, 2364 .readdir = proc_tgid_base_readdir, 2365 }; 2366 2367 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 2368 return proc_pident_lookup(dir, dentry, 2369 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); 2370 } 2371 2372 static const struct inode_operations proc_tgid_base_inode_operations = { 2373 .lookup = proc_tgid_base_lookup, 2374 .getattr = pid_getattr, 2375 .setattr = proc_setattr, 2376 }; 2377 2378 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) 2379 { 2380 struct dentry *dentry, *leader, *dir; 2381 char buf[PROC_NUMBUF]; 2382 struct qstr name; 2383 2384 name.name = buf; 2385 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2386 dentry = d_hash_and_lookup(mnt->mnt_root, &name); 2387 if (dentry) { 2388 if (!(current->flags & PF_EXITING)) 2389 shrink_dcache_parent(dentry); 2390 d_drop(dentry); 2391 dput(dentry); 2392 } 2393 2394 if (tgid == 0) 2395 goto out; 2396 2397 name.name = buf; 2398 name.len = snprintf(buf, sizeof(buf), "%d", tgid); 2399 leader = d_hash_and_lookup(mnt->mnt_root, &name); 2400 if (!leader) 2401 goto out; 2402 2403 name.name = "task"; 2404 name.len = strlen(name.name); 2405 dir = d_hash_and_lookup(leader, &name); 2406 if (!dir) 2407 goto out_put_leader; 2408 2409 name.name = buf; 2410 name.len = snprintf(buf, sizeof(buf), "%d", pid); 2411 dentry = d_hash_and_lookup(dir, &name); 2412 if (dentry) { 2413 shrink_dcache_parent(dentry); 2414 d_drop(dentry); 2415 dput(dentry); 2416 } 2417 2418 dput(dir); 2419 out_put_leader: 2420 dput(leader); 2421 out: 2422 return; 2423 } 2424 2425 /** 2426 * proc_flush_task - Remove dcache entries for @task from the /proc dcache. 2427 * @task: task that should be flushed. 2428 * 2429 * When flushing dentries from proc, one needs to flush them from global 2430 * proc (proc_mnt) and from all the namespaces' procs this task was seen 2431 * in. This call is supposed to do all of this job. 2432 * 2433 * Looks in the dcache for 2434 * /proc/@pid 2435 * /proc/@tgid/task/@pid 2436 * if either directory is present flushes it and all of it'ts children 2437 * from the dcache. 2438 * 2439 * It is safe and reasonable to cache /proc entries for a task until 2440 * that task exits. After that they just clog up the dcache with 2441 * useless entries, possibly causing useful dcache entries to be 2442 * flushed instead. This routine is proved to flush those useless 2443 * dcache entries at process exit time. 2444 * 2445 * NOTE: This routine is just an optimization so it does not guarantee 2446 * that no dcache entries will exist at process exit time it 2447 * just makes it very unlikely that any will persist. 2448 */ 2449 2450 void proc_flush_task(struct task_struct *task) 2451 { 2452 int i; 2453 struct pid *pid, *tgid = NULL; 2454 struct upid *upid; 2455 2456 pid = task_pid(task); 2457 if (thread_group_leader(task)) 2458 tgid = task_tgid(task); 2459 2460 for (i = 0; i <= pid->level; i++) { 2461 upid = &pid->numbers[i]; 2462 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, 2463 tgid ? tgid->numbers[i].nr : 0); 2464 } 2465 2466 upid = &pid->numbers[pid->level]; 2467 if (upid->nr == 1) 2468 pid_ns_release_proc(upid->ns); 2469 } 2470 2471 static struct dentry *proc_pid_instantiate(struct inode *dir, 2472 struct dentry * dentry, 2473 struct task_struct *task, const void *ptr) 2474 { 2475 struct dentry *error = ERR_PTR(-ENOENT); 2476 struct inode *inode; 2477 2478 inode = proc_pid_make_inode(dir->i_sb, task); 2479 if (!inode) 2480 goto out; 2481 2482 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2483 inode->i_op = &proc_tgid_base_inode_operations; 2484 inode->i_fop = &proc_tgid_base_operations; 2485 inode->i_flags|=S_IMMUTABLE; 2486 inode->i_nlink = 5; 2487 #ifdef CONFIG_SECURITY 2488 inode->i_nlink += 1; 2489 #endif 2490 2491 dentry->d_op = &pid_dentry_operations; 2492 2493 d_add(dentry, inode); 2494 /* Close the race of the process dying before we return the dentry */ 2495 if (pid_revalidate(dentry, NULL)) 2496 error = NULL; 2497 out: 2498 return error; 2499 } 2500 2501 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2502 { 2503 struct dentry *result = ERR_PTR(-ENOENT); 2504 struct task_struct *task; 2505 unsigned tgid; 2506 struct pid_namespace *ns; 2507 2508 result = proc_base_lookup(dir, dentry); 2509 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT) 2510 goto out; 2511 2512 tgid = name_to_int(dentry); 2513 if (tgid == ~0U) 2514 goto out; 2515 2516 ns = dentry->d_sb->s_fs_info; 2517 rcu_read_lock(); 2518 task = find_task_by_pid_ns(tgid, ns); 2519 if (task) 2520 get_task_struct(task); 2521 rcu_read_unlock(); 2522 if (!task) 2523 goto out; 2524 2525 result = proc_pid_instantiate(dir, dentry, task, NULL); 2526 put_task_struct(task); 2527 out: 2528 return result; 2529 } 2530 2531 /* 2532 * Find the first task with tgid >= tgid 2533 * 2534 */ 2535 struct tgid_iter { 2536 unsigned int tgid; 2537 struct task_struct *task; 2538 }; 2539 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) 2540 { 2541 struct pid *pid; 2542 2543 if (iter.task) 2544 put_task_struct(iter.task); 2545 rcu_read_lock(); 2546 retry: 2547 iter.task = NULL; 2548 pid = find_ge_pid(iter.tgid, ns); 2549 if (pid) { 2550 iter.tgid = pid_nr_ns(pid, ns); 2551 iter.task = pid_task(pid, PIDTYPE_PID); 2552 /* What we to know is if the pid we have find is the 2553 * pid of a thread_group_leader. Testing for task 2554 * being a thread_group_leader is the obvious thing 2555 * todo but there is a window when it fails, due to 2556 * the pid transfer logic in de_thread. 2557 * 2558 * So we perform the straight forward test of seeing 2559 * if the pid we have found is the pid of a thread 2560 * group leader, and don't worry if the task we have 2561 * found doesn't happen to be a thread group leader. 2562 * As we don't care in the case of readdir. 2563 */ 2564 if (!iter.task || !has_group_leader_pid(iter.task)) { 2565 iter.tgid += 1; 2566 goto retry; 2567 } 2568 get_task_struct(iter.task); 2569 } 2570 rcu_read_unlock(); 2571 return iter; 2572 } 2573 2574 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff)) 2575 2576 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 2577 struct tgid_iter iter) 2578 { 2579 char name[PROC_NUMBUF]; 2580 int len = snprintf(name, sizeof(name), "%d", iter.tgid); 2581 return proc_fill_cache(filp, dirent, filldir, name, len, 2582 proc_pid_instantiate, iter.task, NULL); 2583 } 2584 2585 /* for the /proc/ directory itself, after non-process stuff has been done */ 2586 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2587 { 2588 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2589 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode); 2590 struct tgid_iter iter; 2591 struct pid_namespace *ns; 2592 2593 if (!reaper) 2594 goto out_no_task; 2595 2596 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { 2597 const struct pid_entry *p = &proc_base_stuff[nr]; 2598 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) 2599 goto out; 2600 } 2601 2602 ns = filp->f_dentry->d_sb->s_fs_info; 2603 iter.task = NULL; 2604 iter.tgid = filp->f_pos - TGID_OFFSET; 2605 for (iter = next_tgid(ns, iter); 2606 iter.task; 2607 iter.tgid += 1, iter = next_tgid(ns, iter)) { 2608 filp->f_pos = iter.tgid + TGID_OFFSET; 2609 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) { 2610 put_task_struct(iter.task); 2611 goto out; 2612 } 2613 } 2614 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; 2615 out: 2616 put_task_struct(reaper); 2617 out_no_task: 2618 return 0; 2619 } 2620 2621 /* 2622 * Tasks 2623 */ 2624 static const struct pid_entry tid_base_stuff[] = { 2625 DIR("fd", S_IRUSR|S_IXUSR, fd), 2626 DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo), 2627 REG("environ", S_IRUSR, environ), 2628 INF("auxv", S_IRUSR, pid_auxv), 2629 ONE("status", S_IRUGO, pid_status), 2630 INF("limits", S_IRUSR, pid_limits), 2631 #ifdef CONFIG_SCHED_DEBUG 2632 REG("sched", S_IRUGO|S_IWUSR, pid_sched), 2633 #endif 2634 INF("cmdline", S_IRUGO, pid_cmdline), 2635 ONE("stat", S_IRUGO, tid_stat), 2636 ONE("statm", S_IRUGO, pid_statm), 2637 REG("maps", S_IRUGO, maps), 2638 #ifdef CONFIG_NUMA 2639 REG("numa_maps", S_IRUGO, numa_maps), 2640 #endif 2641 REG("mem", S_IRUSR|S_IWUSR, mem), 2642 LNK("cwd", cwd), 2643 LNK("root", root), 2644 LNK("exe", exe), 2645 REG("mounts", S_IRUGO, mounts), 2646 #ifdef CONFIG_PROC_PAGE_MONITOR 2647 REG("clear_refs", S_IWUSR, clear_refs), 2648 REG("smaps", S_IRUGO, smaps), 2649 REG("pagemap", S_IRUSR, pagemap), 2650 #endif 2651 #ifdef CONFIG_SECURITY 2652 DIR("attr", S_IRUGO|S_IXUGO, attr_dir), 2653 #endif 2654 #ifdef CONFIG_KALLSYMS 2655 INF("wchan", S_IRUGO, pid_wchan), 2656 #endif 2657 #ifdef CONFIG_SCHEDSTATS 2658 INF("schedstat", S_IRUGO, pid_schedstat), 2659 #endif 2660 #ifdef CONFIG_LATENCYTOP 2661 REG("latency", S_IRUGO, lstats), 2662 #endif 2663 #ifdef CONFIG_PROC_PID_CPUSET 2664 REG("cpuset", S_IRUGO, cpuset), 2665 #endif 2666 #ifdef CONFIG_CGROUPS 2667 REG("cgroup", S_IRUGO, cgroup), 2668 #endif 2669 INF("oom_score", S_IRUGO, oom_score), 2670 REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust), 2671 #ifdef CONFIG_AUDITSYSCALL 2672 REG("loginuid", S_IWUSR|S_IRUGO, loginuid), 2673 REG("sessionid", S_IRUSR, sessionid), 2674 #endif 2675 #ifdef CONFIG_FAULT_INJECTION 2676 REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject), 2677 #endif 2678 }; 2679 2680 static int proc_tid_base_readdir(struct file * filp, 2681 void * dirent, filldir_t filldir) 2682 { 2683 return proc_pident_readdir(filp,dirent,filldir, 2684 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 2685 } 2686 2687 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 2688 return proc_pident_lookup(dir, dentry, 2689 tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); 2690 } 2691 2692 static const struct file_operations proc_tid_base_operations = { 2693 .read = generic_read_dir, 2694 .readdir = proc_tid_base_readdir, 2695 }; 2696 2697 static const struct inode_operations proc_tid_base_inode_operations = { 2698 .lookup = proc_tid_base_lookup, 2699 .getattr = pid_getattr, 2700 .setattr = proc_setattr, 2701 }; 2702 2703 static struct dentry *proc_task_instantiate(struct inode *dir, 2704 struct dentry *dentry, struct task_struct *task, const void *ptr) 2705 { 2706 struct dentry *error = ERR_PTR(-ENOENT); 2707 struct inode *inode; 2708 inode = proc_pid_make_inode(dir->i_sb, task); 2709 2710 if (!inode) 2711 goto out; 2712 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2713 inode->i_op = &proc_tid_base_inode_operations; 2714 inode->i_fop = &proc_tid_base_operations; 2715 inode->i_flags|=S_IMMUTABLE; 2716 inode->i_nlink = 4; 2717 #ifdef CONFIG_SECURITY 2718 inode->i_nlink += 1; 2719 #endif 2720 2721 dentry->d_op = &pid_dentry_operations; 2722 2723 d_add(dentry, inode); 2724 /* Close the race of the process dying before we return the dentry */ 2725 if (pid_revalidate(dentry, NULL)) 2726 error = NULL; 2727 out: 2728 return error; 2729 } 2730 2731 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2732 { 2733 struct dentry *result = ERR_PTR(-ENOENT); 2734 struct task_struct *task; 2735 struct task_struct *leader = get_proc_task(dir); 2736 unsigned tid; 2737 struct pid_namespace *ns; 2738 2739 if (!leader) 2740 goto out_no_task; 2741 2742 tid = name_to_int(dentry); 2743 if (tid == ~0U) 2744 goto out; 2745 2746 ns = dentry->d_sb->s_fs_info; 2747 rcu_read_lock(); 2748 task = find_task_by_pid_ns(tid, ns); 2749 if (task) 2750 get_task_struct(task); 2751 rcu_read_unlock(); 2752 if (!task) 2753 goto out; 2754 if (!same_thread_group(leader, task)) 2755 goto out_drop_task; 2756 2757 result = proc_task_instantiate(dir, dentry, task, NULL); 2758 out_drop_task: 2759 put_task_struct(task); 2760 out: 2761 put_task_struct(leader); 2762 out_no_task: 2763 return result; 2764 } 2765 2766 /* 2767 * Find the first tid of a thread group to return to user space. 2768 * 2769 * Usually this is just the thread group leader, but if the users 2770 * buffer was too small or there was a seek into the middle of the 2771 * directory we have more work todo. 2772 * 2773 * In the case of a short read we start with find_task_by_pid. 2774 * 2775 * In the case of a seek we start with the leader and walk nr 2776 * threads past it. 2777 */ 2778 static struct task_struct *first_tid(struct task_struct *leader, 2779 int tid, int nr, struct pid_namespace *ns) 2780 { 2781 struct task_struct *pos; 2782 2783 rcu_read_lock(); 2784 /* Attempt to start with the pid of a thread */ 2785 if (tid && (nr > 0)) { 2786 pos = find_task_by_pid_ns(tid, ns); 2787 if (pos && (pos->group_leader == leader)) 2788 goto found; 2789 } 2790 2791 /* If nr exceeds the number of threads there is nothing todo */ 2792 pos = NULL; 2793 if (nr && nr >= get_nr_threads(leader)) 2794 goto out; 2795 2796 /* If we haven't found our starting place yet start 2797 * with the leader and walk nr threads forward. 2798 */ 2799 for (pos = leader; nr > 0; --nr) { 2800 pos = next_thread(pos); 2801 if (pos == leader) { 2802 pos = NULL; 2803 goto out; 2804 } 2805 } 2806 found: 2807 get_task_struct(pos); 2808 out: 2809 rcu_read_unlock(); 2810 return pos; 2811 } 2812 2813 /* 2814 * Find the next thread in the thread list. 2815 * Return NULL if there is an error or no next thread. 2816 * 2817 * The reference to the input task_struct is released. 2818 */ 2819 static struct task_struct *next_tid(struct task_struct *start) 2820 { 2821 struct task_struct *pos = NULL; 2822 rcu_read_lock(); 2823 if (pid_alive(start)) { 2824 pos = next_thread(start); 2825 if (thread_group_leader(pos)) 2826 pos = NULL; 2827 else 2828 get_task_struct(pos); 2829 } 2830 rcu_read_unlock(); 2831 put_task_struct(start); 2832 return pos; 2833 } 2834 2835 static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 2836 struct task_struct *task, int tid) 2837 { 2838 char name[PROC_NUMBUF]; 2839 int len = snprintf(name, sizeof(name), "%d", tid); 2840 return proc_fill_cache(filp, dirent, filldir, name, len, 2841 proc_task_instantiate, task, NULL); 2842 } 2843 2844 /* for the /proc/TGID/task/ directories */ 2845 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 2846 { 2847 struct dentry *dentry = filp->f_path.dentry; 2848 struct inode *inode = dentry->d_inode; 2849 struct task_struct *leader = NULL; 2850 struct task_struct *task; 2851 int retval = -ENOENT; 2852 ino_t ino; 2853 int tid; 2854 unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */ 2855 struct pid_namespace *ns; 2856 2857 task = get_proc_task(inode); 2858 if (!task) 2859 goto out_no_task; 2860 rcu_read_lock(); 2861 if (pid_alive(task)) { 2862 leader = task->group_leader; 2863 get_task_struct(leader); 2864 } 2865 rcu_read_unlock(); 2866 put_task_struct(task); 2867 if (!leader) 2868 goto out_no_task; 2869 retval = 0; 2870 2871 switch (pos) { 2872 case 0: 2873 ino = inode->i_ino; 2874 if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0) 2875 goto out; 2876 pos++; 2877 /* fall through */ 2878 case 1: 2879 ino = parent_ino(dentry); 2880 if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0) 2881 goto out; 2882 pos++; 2883 /* fall through */ 2884 } 2885 2886 /* f_version caches the tgid value that the last readdir call couldn't 2887 * return. lseek aka telldir automagically resets f_version to 0. 2888 */ 2889 ns = filp->f_dentry->d_sb->s_fs_info; 2890 tid = (int)filp->f_version; 2891 filp->f_version = 0; 2892 for (task = first_tid(leader, tid, pos - 2, ns); 2893 task; 2894 task = next_tid(task), pos++) { 2895 tid = task_pid_nr_ns(task, ns); 2896 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { 2897 /* returning this tgid failed, save it as the first 2898 * pid for the next readir call */ 2899 filp->f_version = (u64)tid; 2900 put_task_struct(task); 2901 break; 2902 } 2903 } 2904 out: 2905 filp->f_pos = pos; 2906 put_task_struct(leader); 2907 out_no_task: 2908 return retval; 2909 } 2910 2911 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 2912 { 2913 struct inode *inode = dentry->d_inode; 2914 struct task_struct *p = get_proc_task(inode); 2915 generic_fillattr(inode, stat); 2916 2917 if (p) { 2918 rcu_read_lock(); 2919 stat->nlink += get_nr_threads(p); 2920 rcu_read_unlock(); 2921 put_task_struct(p); 2922 } 2923 2924 return 0; 2925 } 2926 2927 static const struct inode_operations proc_task_inode_operations = { 2928 .lookup = proc_task_lookup, 2929 .getattr = proc_task_getattr, 2930 .setattr = proc_setattr, 2931 }; 2932 2933 static const struct file_operations proc_task_operations = { 2934 .read = generic_read_dir, 2935 .readdir = proc_task_readdir, 2936 }; 2937