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/config.h> 53 #include <linux/errno.h> 54 #include <linux/time.h> 55 #include <linux/proc_fs.h> 56 #include <linux/stat.h> 57 #include <linux/init.h> 58 #include <linux/capability.h> 59 #include <linux/file.h> 60 #include <linux/string.h> 61 #include <linux/seq_file.h> 62 #include <linux/namei.h> 63 #include <linux/namespace.h> 64 #include <linux/mm.h> 65 #include <linux/smp_lock.h> 66 #include <linux/rcupdate.h> 67 #include <linux/kallsyms.h> 68 #include <linux/mount.h> 69 #include <linux/security.h> 70 #include <linux/ptrace.h> 71 #include <linux/seccomp.h> 72 #include <linux/cpuset.h> 73 #include <linux/audit.h> 74 #include <linux/poll.h> 75 #include "internal.h" 76 77 /* 78 * For hysterical raisins we keep the same inumbers as in the old procfs. 79 * Feel free to change the macro below - just keep the range distinct from 80 * inumbers of the rest of procfs (currently those are in 0x0000--0xffff). 81 * As soon as we'll get a separate superblock we will be able to forget 82 * about magical ranges too. 83 */ 84 85 #define fake_ino(pid,ino) (((pid)<<16)|(ino)) 86 87 enum pid_directory_inos { 88 PROC_TGID_INO = 2, 89 PROC_TGID_TASK, 90 PROC_TGID_STATUS, 91 PROC_TGID_MEM, 92 #ifdef CONFIG_SECCOMP 93 PROC_TGID_SECCOMP, 94 #endif 95 PROC_TGID_CWD, 96 PROC_TGID_ROOT, 97 PROC_TGID_EXE, 98 PROC_TGID_FD, 99 PROC_TGID_ENVIRON, 100 PROC_TGID_AUXV, 101 PROC_TGID_CMDLINE, 102 PROC_TGID_STAT, 103 PROC_TGID_STATM, 104 PROC_TGID_MAPS, 105 PROC_TGID_NUMA_MAPS, 106 PROC_TGID_MOUNTS, 107 PROC_TGID_MOUNTSTATS, 108 PROC_TGID_WCHAN, 109 #ifdef CONFIG_MMU 110 PROC_TGID_SMAPS, 111 #endif 112 #ifdef CONFIG_SCHEDSTATS 113 PROC_TGID_SCHEDSTAT, 114 #endif 115 #ifdef CONFIG_CPUSETS 116 PROC_TGID_CPUSET, 117 #endif 118 #ifdef CONFIG_SECURITY 119 PROC_TGID_ATTR, 120 PROC_TGID_ATTR_CURRENT, 121 PROC_TGID_ATTR_PREV, 122 PROC_TGID_ATTR_EXEC, 123 PROC_TGID_ATTR_FSCREATE, 124 #endif 125 #ifdef CONFIG_AUDITSYSCALL 126 PROC_TGID_LOGINUID, 127 #endif 128 PROC_TGID_OOM_SCORE, 129 PROC_TGID_OOM_ADJUST, 130 PROC_TID_INO, 131 PROC_TID_STATUS, 132 PROC_TID_MEM, 133 #ifdef CONFIG_SECCOMP 134 PROC_TID_SECCOMP, 135 #endif 136 PROC_TID_CWD, 137 PROC_TID_ROOT, 138 PROC_TID_EXE, 139 PROC_TID_FD, 140 PROC_TID_ENVIRON, 141 PROC_TID_AUXV, 142 PROC_TID_CMDLINE, 143 PROC_TID_STAT, 144 PROC_TID_STATM, 145 PROC_TID_MAPS, 146 PROC_TID_NUMA_MAPS, 147 PROC_TID_MOUNTS, 148 PROC_TID_MOUNTSTATS, 149 PROC_TID_WCHAN, 150 #ifdef CONFIG_MMU 151 PROC_TID_SMAPS, 152 #endif 153 #ifdef CONFIG_SCHEDSTATS 154 PROC_TID_SCHEDSTAT, 155 #endif 156 #ifdef CONFIG_CPUSETS 157 PROC_TID_CPUSET, 158 #endif 159 #ifdef CONFIG_SECURITY 160 PROC_TID_ATTR, 161 PROC_TID_ATTR_CURRENT, 162 PROC_TID_ATTR_PREV, 163 PROC_TID_ATTR_EXEC, 164 PROC_TID_ATTR_FSCREATE, 165 #endif 166 #ifdef CONFIG_AUDITSYSCALL 167 PROC_TID_LOGINUID, 168 #endif 169 PROC_TID_OOM_SCORE, 170 PROC_TID_OOM_ADJUST, 171 172 /* Add new entries before this */ 173 PROC_TID_FD_DIR = 0x8000, /* 0x8000-0xffff */ 174 }; 175 176 struct pid_entry { 177 int type; 178 int len; 179 char *name; 180 mode_t mode; 181 }; 182 183 #define E(type,name,mode) {(type),sizeof(name)-1,(name),(mode)} 184 185 static struct pid_entry tgid_base_stuff[] = { 186 E(PROC_TGID_TASK, "task", S_IFDIR|S_IRUGO|S_IXUGO), 187 E(PROC_TGID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR), 188 E(PROC_TGID_ENVIRON, "environ", S_IFREG|S_IRUSR), 189 E(PROC_TGID_AUXV, "auxv", S_IFREG|S_IRUSR), 190 E(PROC_TGID_STATUS, "status", S_IFREG|S_IRUGO), 191 E(PROC_TGID_CMDLINE, "cmdline", S_IFREG|S_IRUGO), 192 E(PROC_TGID_STAT, "stat", S_IFREG|S_IRUGO), 193 E(PROC_TGID_STATM, "statm", S_IFREG|S_IRUGO), 194 E(PROC_TGID_MAPS, "maps", S_IFREG|S_IRUGO), 195 #ifdef CONFIG_NUMA 196 E(PROC_TGID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO), 197 #endif 198 E(PROC_TGID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR), 199 #ifdef CONFIG_SECCOMP 200 E(PROC_TGID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR), 201 #endif 202 E(PROC_TGID_CWD, "cwd", S_IFLNK|S_IRWXUGO), 203 E(PROC_TGID_ROOT, "root", S_IFLNK|S_IRWXUGO), 204 E(PROC_TGID_EXE, "exe", S_IFLNK|S_IRWXUGO), 205 E(PROC_TGID_MOUNTS, "mounts", S_IFREG|S_IRUGO), 206 E(PROC_TGID_MOUNTSTATS, "mountstats", S_IFREG|S_IRUSR), 207 #ifdef CONFIG_MMU 208 E(PROC_TGID_SMAPS, "smaps", S_IFREG|S_IRUGO), 209 #endif 210 #ifdef CONFIG_SECURITY 211 E(PROC_TGID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO), 212 #endif 213 #ifdef CONFIG_KALLSYMS 214 E(PROC_TGID_WCHAN, "wchan", S_IFREG|S_IRUGO), 215 #endif 216 #ifdef CONFIG_SCHEDSTATS 217 E(PROC_TGID_SCHEDSTAT, "schedstat", S_IFREG|S_IRUGO), 218 #endif 219 #ifdef CONFIG_CPUSETS 220 E(PROC_TGID_CPUSET, "cpuset", S_IFREG|S_IRUGO), 221 #endif 222 E(PROC_TGID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO), 223 E(PROC_TGID_OOM_ADJUST,"oom_adj", S_IFREG|S_IRUGO|S_IWUSR), 224 #ifdef CONFIG_AUDITSYSCALL 225 E(PROC_TGID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO), 226 #endif 227 {0,0,NULL,0} 228 }; 229 static struct pid_entry tid_base_stuff[] = { 230 E(PROC_TID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR), 231 E(PROC_TID_ENVIRON, "environ", S_IFREG|S_IRUSR), 232 E(PROC_TID_AUXV, "auxv", S_IFREG|S_IRUSR), 233 E(PROC_TID_STATUS, "status", S_IFREG|S_IRUGO), 234 E(PROC_TID_CMDLINE, "cmdline", S_IFREG|S_IRUGO), 235 E(PROC_TID_STAT, "stat", S_IFREG|S_IRUGO), 236 E(PROC_TID_STATM, "statm", S_IFREG|S_IRUGO), 237 E(PROC_TID_MAPS, "maps", S_IFREG|S_IRUGO), 238 #ifdef CONFIG_NUMA 239 E(PROC_TID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO), 240 #endif 241 E(PROC_TID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR), 242 #ifdef CONFIG_SECCOMP 243 E(PROC_TID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR), 244 #endif 245 E(PROC_TID_CWD, "cwd", S_IFLNK|S_IRWXUGO), 246 E(PROC_TID_ROOT, "root", S_IFLNK|S_IRWXUGO), 247 E(PROC_TID_EXE, "exe", S_IFLNK|S_IRWXUGO), 248 E(PROC_TID_MOUNTS, "mounts", S_IFREG|S_IRUGO), 249 #ifdef CONFIG_MMU 250 E(PROC_TID_SMAPS, "smaps", S_IFREG|S_IRUGO), 251 #endif 252 #ifdef CONFIG_SECURITY 253 E(PROC_TID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO), 254 #endif 255 #ifdef CONFIG_KALLSYMS 256 E(PROC_TID_WCHAN, "wchan", S_IFREG|S_IRUGO), 257 #endif 258 #ifdef CONFIG_SCHEDSTATS 259 E(PROC_TID_SCHEDSTAT, "schedstat",S_IFREG|S_IRUGO), 260 #endif 261 #ifdef CONFIG_CPUSETS 262 E(PROC_TID_CPUSET, "cpuset", S_IFREG|S_IRUGO), 263 #endif 264 E(PROC_TID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO), 265 E(PROC_TID_OOM_ADJUST, "oom_adj", S_IFREG|S_IRUGO|S_IWUSR), 266 #ifdef CONFIG_AUDITSYSCALL 267 E(PROC_TID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO), 268 #endif 269 {0,0,NULL,0} 270 }; 271 272 #ifdef CONFIG_SECURITY 273 static struct pid_entry tgid_attr_stuff[] = { 274 E(PROC_TGID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO), 275 E(PROC_TGID_ATTR_PREV, "prev", S_IFREG|S_IRUGO), 276 E(PROC_TGID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO), 277 E(PROC_TGID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO), 278 {0,0,NULL,0} 279 }; 280 static struct pid_entry tid_attr_stuff[] = { 281 E(PROC_TID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO), 282 E(PROC_TID_ATTR_PREV, "prev", S_IFREG|S_IRUGO), 283 E(PROC_TID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO), 284 E(PROC_TID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO), 285 {0,0,NULL,0} 286 }; 287 #endif 288 289 #undef E 290 291 static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 292 { 293 struct task_struct *task = proc_task(inode); 294 struct files_struct *files; 295 struct file *file; 296 int fd = proc_type(inode) - PROC_TID_FD_DIR; 297 298 files = get_files_struct(task); 299 if (files) { 300 rcu_read_lock(); 301 file = fcheck_files(files, fd); 302 if (file) { 303 *mnt = mntget(file->f_vfsmnt); 304 *dentry = dget(file->f_dentry); 305 rcu_read_unlock(); 306 put_files_struct(files); 307 return 0; 308 } 309 rcu_read_unlock(); 310 put_files_struct(files); 311 } 312 return -ENOENT; 313 } 314 315 static struct fs_struct *get_fs_struct(struct task_struct *task) 316 { 317 struct fs_struct *fs; 318 task_lock(task); 319 fs = task->fs; 320 if(fs) 321 atomic_inc(&fs->count); 322 task_unlock(task); 323 return fs; 324 } 325 326 static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 327 { 328 struct fs_struct *fs = get_fs_struct(proc_task(inode)); 329 int result = -ENOENT; 330 if (fs) { 331 read_lock(&fs->lock); 332 *mnt = mntget(fs->pwdmnt); 333 *dentry = dget(fs->pwd); 334 read_unlock(&fs->lock); 335 result = 0; 336 put_fs_struct(fs); 337 } 338 return result; 339 } 340 341 static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) 342 { 343 struct fs_struct *fs = get_fs_struct(proc_task(inode)); 344 int result = -ENOENT; 345 if (fs) { 346 read_lock(&fs->lock); 347 *mnt = mntget(fs->rootmnt); 348 *dentry = dget(fs->root); 349 read_unlock(&fs->lock); 350 result = 0; 351 put_fs_struct(fs); 352 } 353 return result; 354 } 355 356 357 /* Same as proc_root_link, but this addionally tries to get fs from other 358 * threads in the group */ 359 static int proc_task_root_link(struct inode *inode, struct dentry **dentry, 360 struct vfsmount **mnt) 361 { 362 struct fs_struct *fs; 363 int result = -ENOENT; 364 struct task_struct *leader = proc_task(inode); 365 366 task_lock(leader); 367 fs = leader->fs; 368 if (fs) { 369 atomic_inc(&fs->count); 370 task_unlock(leader); 371 } else { 372 /* Try to get fs from other threads */ 373 task_unlock(leader); 374 read_lock(&tasklist_lock); 375 if (pid_alive(leader)) { 376 struct task_struct *task = leader; 377 378 while ((task = next_thread(task)) != leader) { 379 task_lock(task); 380 fs = task->fs; 381 if (fs) { 382 atomic_inc(&fs->count); 383 task_unlock(task); 384 break; 385 } 386 task_unlock(task); 387 } 388 } 389 read_unlock(&tasklist_lock); 390 } 391 392 if (fs) { 393 read_lock(&fs->lock); 394 *mnt = mntget(fs->rootmnt); 395 *dentry = dget(fs->root); 396 read_unlock(&fs->lock); 397 result = 0; 398 put_fs_struct(fs); 399 } 400 return result; 401 } 402 403 404 #define MAY_PTRACE(task) \ 405 (task == current || \ 406 (task->parent == current && \ 407 (task->ptrace & PT_PTRACED) && \ 408 (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \ 409 security_ptrace(current,task) == 0)) 410 411 static int proc_pid_environ(struct task_struct *task, char * buffer) 412 { 413 int res = 0; 414 struct mm_struct *mm = get_task_mm(task); 415 if (mm) { 416 unsigned int len = mm->env_end - mm->env_start; 417 if (len > PAGE_SIZE) 418 len = PAGE_SIZE; 419 res = access_process_vm(task, mm->env_start, buffer, len, 0); 420 if (!ptrace_may_attach(task)) 421 res = -ESRCH; 422 mmput(mm); 423 } 424 return res; 425 } 426 427 static int proc_pid_cmdline(struct task_struct *task, char * buffer) 428 { 429 int res = 0; 430 unsigned int len; 431 struct mm_struct *mm = get_task_mm(task); 432 if (!mm) 433 goto out; 434 if (!mm->arg_end) 435 goto out_mm; /* Shh! No looking before we're done */ 436 437 len = mm->arg_end - mm->arg_start; 438 439 if (len > PAGE_SIZE) 440 len = PAGE_SIZE; 441 442 res = access_process_vm(task, mm->arg_start, buffer, len, 0); 443 444 // If the nul at the end of args has been overwritten, then 445 // assume application is using setproctitle(3). 446 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { 447 len = strnlen(buffer, res); 448 if (len < res) { 449 res = len; 450 } else { 451 len = mm->env_end - mm->env_start; 452 if (len > PAGE_SIZE - res) 453 len = PAGE_SIZE - res; 454 res += access_process_vm(task, mm->env_start, buffer+res, len, 0); 455 res = strnlen(buffer, res); 456 } 457 } 458 out_mm: 459 mmput(mm); 460 out: 461 return res; 462 } 463 464 static int proc_pid_auxv(struct task_struct *task, char *buffer) 465 { 466 int res = 0; 467 struct mm_struct *mm = get_task_mm(task); 468 if (mm) { 469 unsigned int nwords = 0; 470 do 471 nwords += 2; 472 while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ 473 res = nwords * sizeof(mm->saved_auxv[0]); 474 if (res > PAGE_SIZE) 475 res = PAGE_SIZE; 476 memcpy(buffer, mm->saved_auxv, res); 477 mmput(mm); 478 } 479 return res; 480 } 481 482 483 #ifdef CONFIG_KALLSYMS 484 /* 485 * Provides a wchan file via kallsyms in a proper one-value-per-file format. 486 * Returns the resolved symbol. If that fails, simply return the address. 487 */ 488 static int proc_pid_wchan(struct task_struct *task, char *buffer) 489 { 490 char *modname; 491 const char *sym_name; 492 unsigned long wchan, size, offset; 493 char namebuf[KSYM_NAME_LEN+1]; 494 495 wchan = get_wchan(task); 496 497 sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf); 498 if (sym_name) 499 return sprintf(buffer, "%s", sym_name); 500 return sprintf(buffer, "%lu", wchan); 501 } 502 #endif /* CONFIG_KALLSYMS */ 503 504 #ifdef CONFIG_SCHEDSTATS 505 /* 506 * Provides /proc/PID/schedstat 507 */ 508 static int proc_pid_schedstat(struct task_struct *task, char *buffer) 509 { 510 return sprintf(buffer, "%lu %lu %lu\n", 511 task->sched_info.cpu_time, 512 task->sched_info.run_delay, 513 task->sched_info.pcnt); 514 } 515 #endif 516 517 /* The badness from the OOM killer */ 518 unsigned long badness(struct task_struct *p, unsigned long uptime); 519 static int proc_oom_score(struct task_struct *task, char *buffer) 520 { 521 unsigned long points; 522 struct timespec uptime; 523 524 do_posix_clock_monotonic_gettime(&uptime); 525 points = badness(task, uptime.tv_sec); 526 return sprintf(buffer, "%lu\n", points); 527 } 528 529 /************************************************************************/ 530 /* Here the fs part begins */ 531 /************************************************************************/ 532 533 /* permission checks */ 534 535 /* If the process being read is separated by chroot from the reading process, 536 * don't let the reader access the threads. 537 */ 538 static int proc_check_chroot(struct dentry *root, struct vfsmount *vfsmnt) 539 { 540 struct dentry *de, *base; 541 struct vfsmount *our_vfsmnt, *mnt; 542 int res = 0; 543 read_lock(¤t->fs->lock); 544 our_vfsmnt = mntget(current->fs->rootmnt); 545 base = dget(current->fs->root); 546 read_unlock(¤t->fs->lock); 547 548 spin_lock(&vfsmount_lock); 549 de = root; 550 mnt = vfsmnt; 551 552 while (vfsmnt != our_vfsmnt) { 553 if (vfsmnt == vfsmnt->mnt_parent) 554 goto out; 555 de = vfsmnt->mnt_mountpoint; 556 vfsmnt = vfsmnt->mnt_parent; 557 } 558 559 if (!is_subdir(de, base)) 560 goto out; 561 spin_unlock(&vfsmount_lock); 562 563 exit: 564 dput(base); 565 mntput(our_vfsmnt); 566 dput(root); 567 mntput(mnt); 568 return res; 569 out: 570 spin_unlock(&vfsmount_lock); 571 res = -EACCES; 572 goto exit; 573 } 574 575 static int proc_check_root(struct inode *inode) 576 { 577 struct dentry *root; 578 struct vfsmount *vfsmnt; 579 580 if (proc_root_link(inode, &root, &vfsmnt)) /* Ewww... */ 581 return -ENOENT; 582 return proc_check_chroot(root, vfsmnt); 583 } 584 585 static int proc_permission(struct inode *inode, int mask, struct nameidata *nd) 586 { 587 if (generic_permission(inode, mask, NULL) != 0) 588 return -EACCES; 589 return proc_check_root(inode); 590 } 591 592 static int proc_task_permission(struct inode *inode, int mask, struct nameidata *nd) 593 { 594 struct dentry *root; 595 struct vfsmount *vfsmnt; 596 597 if (generic_permission(inode, mask, NULL) != 0) 598 return -EACCES; 599 600 if (proc_task_root_link(inode, &root, &vfsmnt)) 601 return -ENOENT; 602 603 return proc_check_chroot(root, vfsmnt); 604 } 605 606 extern struct seq_operations proc_pid_maps_op; 607 static int maps_open(struct inode *inode, struct file *file) 608 { 609 struct task_struct *task = proc_task(inode); 610 int ret = seq_open(file, &proc_pid_maps_op); 611 if (!ret) { 612 struct seq_file *m = file->private_data; 613 m->private = task; 614 } 615 return ret; 616 } 617 618 static struct file_operations proc_maps_operations = { 619 .open = maps_open, 620 .read = seq_read, 621 .llseek = seq_lseek, 622 .release = seq_release, 623 }; 624 625 #ifdef CONFIG_NUMA 626 extern struct seq_operations proc_pid_numa_maps_op; 627 static int numa_maps_open(struct inode *inode, struct file *file) 628 { 629 struct task_struct *task = proc_task(inode); 630 int ret = seq_open(file, &proc_pid_numa_maps_op); 631 if (!ret) { 632 struct seq_file *m = file->private_data; 633 m->private = task; 634 } 635 return ret; 636 } 637 638 static struct file_operations proc_numa_maps_operations = { 639 .open = numa_maps_open, 640 .read = seq_read, 641 .llseek = seq_lseek, 642 .release = seq_release, 643 }; 644 #endif 645 646 #ifdef CONFIG_MMU 647 extern struct seq_operations proc_pid_smaps_op; 648 static int smaps_open(struct inode *inode, struct file *file) 649 { 650 struct task_struct *task = proc_task(inode); 651 int ret = seq_open(file, &proc_pid_smaps_op); 652 if (!ret) { 653 struct seq_file *m = file->private_data; 654 m->private = task; 655 } 656 return ret; 657 } 658 659 static struct file_operations proc_smaps_operations = { 660 .open = smaps_open, 661 .read = seq_read, 662 .llseek = seq_lseek, 663 .release = seq_release, 664 }; 665 #endif 666 667 extern struct seq_operations mounts_op; 668 struct proc_mounts { 669 struct seq_file m; 670 int event; 671 }; 672 673 static int mounts_open(struct inode *inode, struct file *file) 674 { 675 struct task_struct *task = proc_task(inode); 676 struct namespace *namespace; 677 struct proc_mounts *p; 678 int ret = -EINVAL; 679 680 task_lock(task); 681 namespace = task->namespace; 682 if (namespace) 683 get_namespace(namespace); 684 task_unlock(task); 685 686 if (namespace) { 687 ret = -ENOMEM; 688 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); 689 if (p) { 690 file->private_data = &p->m; 691 ret = seq_open(file, &mounts_op); 692 if (!ret) { 693 p->m.private = namespace; 694 p->event = namespace->event; 695 return 0; 696 } 697 kfree(p); 698 } 699 put_namespace(namespace); 700 } 701 return ret; 702 } 703 704 static int mounts_release(struct inode *inode, struct file *file) 705 { 706 struct seq_file *m = file->private_data; 707 struct namespace *namespace = m->private; 708 put_namespace(namespace); 709 return seq_release(inode, file); 710 } 711 712 static unsigned mounts_poll(struct file *file, poll_table *wait) 713 { 714 struct proc_mounts *p = file->private_data; 715 struct namespace *ns = p->m.private; 716 unsigned res = 0; 717 718 poll_wait(file, &ns->poll, wait); 719 720 spin_lock(&vfsmount_lock); 721 if (p->event != ns->event) { 722 p->event = ns->event; 723 res = POLLERR; 724 } 725 spin_unlock(&vfsmount_lock); 726 727 return res; 728 } 729 730 static struct file_operations proc_mounts_operations = { 731 .open = mounts_open, 732 .read = seq_read, 733 .llseek = seq_lseek, 734 .release = mounts_release, 735 .poll = mounts_poll, 736 }; 737 738 extern struct seq_operations mountstats_op; 739 static int mountstats_open(struct inode *inode, struct file *file) 740 { 741 struct task_struct *task = proc_task(inode); 742 int ret = seq_open(file, &mountstats_op); 743 744 if (!ret) { 745 struct seq_file *m = file->private_data; 746 struct namespace *namespace; 747 task_lock(task); 748 namespace = task->namespace; 749 if (namespace) 750 get_namespace(namespace); 751 task_unlock(task); 752 753 if (namespace) 754 m->private = namespace; 755 else { 756 seq_release(inode, file); 757 ret = -EINVAL; 758 } 759 } 760 return ret; 761 } 762 763 static struct file_operations proc_mountstats_operations = { 764 .open = mountstats_open, 765 .read = seq_read, 766 .llseek = seq_lseek, 767 .release = mounts_release, 768 }; 769 770 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ 771 772 static ssize_t proc_info_read(struct file * file, char __user * buf, 773 size_t count, loff_t *ppos) 774 { 775 struct inode * inode = file->f_dentry->d_inode; 776 unsigned long page; 777 ssize_t length; 778 struct task_struct *task = proc_task(inode); 779 780 if (count > PROC_BLOCK_SIZE) 781 count = PROC_BLOCK_SIZE; 782 if (!(page = __get_free_page(GFP_KERNEL))) 783 return -ENOMEM; 784 785 length = PROC_I(inode)->op.proc_read(task, (char*)page); 786 787 if (length >= 0) 788 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 789 free_page(page); 790 return length; 791 } 792 793 static struct file_operations proc_info_file_operations = { 794 .read = proc_info_read, 795 }; 796 797 static int mem_open(struct inode* inode, struct file* file) 798 { 799 file->private_data = (void*)((long)current->self_exec_id); 800 return 0; 801 } 802 803 static ssize_t mem_read(struct file * file, char __user * buf, 804 size_t count, loff_t *ppos) 805 { 806 struct task_struct *task = proc_task(file->f_dentry->d_inode); 807 char *page; 808 unsigned long src = *ppos; 809 int ret = -ESRCH; 810 struct mm_struct *mm; 811 812 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 813 goto out; 814 815 ret = -ENOMEM; 816 page = (char *)__get_free_page(GFP_USER); 817 if (!page) 818 goto out; 819 820 ret = 0; 821 822 mm = get_task_mm(task); 823 if (!mm) 824 goto out_free; 825 826 ret = -EIO; 827 828 if (file->private_data != (void*)((long)current->self_exec_id)) 829 goto out_put; 830 831 ret = 0; 832 833 while (count > 0) { 834 int this_len, retval; 835 836 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 837 retval = access_process_vm(task, src, page, this_len, 0); 838 if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) { 839 if (!ret) 840 ret = -EIO; 841 break; 842 } 843 844 if (copy_to_user(buf, page, retval)) { 845 ret = -EFAULT; 846 break; 847 } 848 849 ret += retval; 850 src += retval; 851 buf += retval; 852 count -= retval; 853 } 854 *ppos = src; 855 856 out_put: 857 mmput(mm); 858 out_free: 859 free_page((unsigned long) page); 860 out: 861 return ret; 862 } 863 864 #define mem_write NULL 865 866 #ifndef mem_write 867 /* This is a security hazard */ 868 static ssize_t mem_write(struct file * file, const char * buf, 869 size_t count, loff_t *ppos) 870 { 871 int copied = 0; 872 char *page; 873 struct task_struct *task = proc_task(file->f_dentry->d_inode); 874 unsigned long dst = *ppos; 875 876 if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) 877 return -ESRCH; 878 879 page = (char *)__get_free_page(GFP_USER); 880 if (!page) 881 return -ENOMEM; 882 883 while (count > 0) { 884 int this_len, retval; 885 886 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; 887 if (copy_from_user(page, buf, this_len)) { 888 copied = -EFAULT; 889 break; 890 } 891 retval = access_process_vm(task, dst, page, this_len, 1); 892 if (!retval) { 893 if (!copied) 894 copied = -EIO; 895 break; 896 } 897 copied += retval; 898 buf += retval; 899 dst += retval; 900 count -= retval; 901 } 902 *ppos = dst; 903 free_page((unsigned long) page); 904 return copied; 905 } 906 #endif 907 908 static loff_t mem_lseek(struct file * file, loff_t offset, int orig) 909 { 910 switch (orig) { 911 case 0: 912 file->f_pos = offset; 913 break; 914 case 1: 915 file->f_pos += offset; 916 break; 917 default: 918 return -EINVAL; 919 } 920 force_successful_syscall_return(); 921 return file->f_pos; 922 } 923 924 static struct file_operations proc_mem_operations = { 925 .llseek = mem_lseek, 926 .read = mem_read, 927 .write = mem_write, 928 .open = mem_open, 929 }; 930 931 static ssize_t oom_adjust_read(struct file *file, char __user *buf, 932 size_t count, loff_t *ppos) 933 { 934 struct task_struct *task = proc_task(file->f_dentry->d_inode); 935 char buffer[8]; 936 size_t len; 937 int oom_adjust = task->oomkilladj; 938 loff_t __ppos = *ppos; 939 940 len = sprintf(buffer, "%i\n", oom_adjust); 941 if (__ppos >= len) 942 return 0; 943 if (count > len-__ppos) 944 count = len-__ppos; 945 if (copy_to_user(buf, buffer + __ppos, count)) 946 return -EFAULT; 947 *ppos = __ppos + count; 948 return count; 949 } 950 951 static ssize_t oom_adjust_write(struct file *file, const char __user *buf, 952 size_t count, loff_t *ppos) 953 { 954 struct task_struct *task = proc_task(file->f_dentry->d_inode); 955 char buffer[8], *end; 956 int oom_adjust; 957 958 if (!capable(CAP_SYS_RESOURCE)) 959 return -EPERM; 960 memset(buffer, 0, 8); 961 if (count > 6) 962 count = 6; 963 if (copy_from_user(buffer, buf, count)) 964 return -EFAULT; 965 oom_adjust = simple_strtol(buffer, &end, 0); 966 if ((oom_adjust < -16 || oom_adjust > 15) && oom_adjust != OOM_DISABLE) 967 return -EINVAL; 968 if (*end == '\n') 969 end++; 970 task->oomkilladj = oom_adjust; 971 if (end - buffer == 0) 972 return -EIO; 973 return end - buffer; 974 } 975 976 static struct file_operations proc_oom_adjust_operations = { 977 .read = oom_adjust_read, 978 .write = oom_adjust_write, 979 }; 980 981 static struct inode_operations proc_mem_inode_operations = { 982 .permission = proc_permission, 983 }; 984 985 #ifdef CONFIG_AUDITSYSCALL 986 #define TMPBUFLEN 21 987 static ssize_t proc_loginuid_read(struct file * file, char __user * buf, 988 size_t count, loff_t *ppos) 989 { 990 struct inode * inode = file->f_dentry->d_inode; 991 struct task_struct *task = proc_task(inode); 992 ssize_t length; 993 char tmpbuf[TMPBUFLEN]; 994 995 length = scnprintf(tmpbuf, TMPBUFLEN, "%u", 996 audit_get_loginuid(task->audit_context)); 997 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); 998 } 999 1000 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, 1001 size_t count, loff_t *ppos) 1002 { 1003 struct inode * inode = file->f_dentry->d_inode; 1004 char *page, *tmp; 1005 ssize_t length; 1006 struct task_struct *task = proc_task(inode); 1007 uid_t loginuid; 1008 1009 if (!capable(CAP_AUDIT_CONTROL)) 1010 return -EPERM; 1011 1012 if (current != task) 1013 return -EPERM; 1014 1015 if (count > PAGE_SIZE) 1016 count = PAGE_SIZE; 1017 1018 if (*ppos != 0) { 1019 /* No partial writes. */ 1020 return -EINVAL; 1021 } 1022 page = (char*)__get_free_page(GFP_USER); 1023 if (!page) 1024 return -ENOMEM; 1025 length = -EFAULT; 1026 if (copy_from_user(page, buf, count)) 1027 goto out_free_page; 1028 1029 loginuid = simple_strtoul(page, &tmp, 10); 1030 if (tmp == page) { 1031 length = -EINVAL; 1032 goto out_free_page; 1033 1034 } 1035 length = audit_set_loginuid(task, loginuid); 1036 if (likely(length == 0)) 1037 length = count; 1038 1039 out_free_page: 1040 free_page((unsigned long) page); 1041 return length; 1042 } 1043 1044 static struct file_operations proc_loginuid_operations = { 1045 .read = proc_loginuid_read, 1046 .write = proc_loginuid_write, 1047 }; 1048 #endif 1049 1050 #ifdef CONFIG_SECCOMP 1051 static ssize_t seccomp_read(struct file *file, char __user *buf, 1052 size_t count, loff_t *ppos) 1053 { 1054 struct task_struct *tsk = proc_task(file->f_dentry->d_inode); 1055 char __buf[20]; 1056 loff_t __ppos = *ppos; 1057 size_t len; 1058 1059 /* no need to print the trailing zero, so use only len */ 1060 len = sprintf(__buf, "%u\n", tsk->seccomp.mode); 1061 if (__ppos >= len) 1062 return 0; 1063 if (count > len - __ppos) 1064 count = len - __ppos; 1065 if (copy_to_user(buf, __buf + __ppos, count)) 1066 return -EFAULT; 1067 *ppos = __ppos + count; 1068 return count; 1069 } 1070 1071 static ssize_t seccomp_write(struct file *file, const char __user *buf, 1072 size_t count, loff_t *ppos) 1073 { 1074 struct task_struct *tsk = proc_task(file->f_dentry->d_inode); 1075 char __buf[20], *end; 1076 unsigned int seccomp_mode; 1077 1078 /* can set it only once to be even more secure */ 1079 if (unlikely(tsk->seccomp.mode)) 1080 return -EPERM; 1081 1082 memset(__buf, 0, sizeof(__buf)); 1083 count = min(count, sizeof(__buf) - 1); 1084 if (copy_from_user(__buf, buf, count)) 1085 return -EFAULT; 1086 seccomp_mode = simple_strtoul(__buf, &end, 0); 1087 if (*end == '\n') 1088 end++; 1089 if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) { 1090 tsk->seccomp.mode = seccomp_mode; 1091 set_tsk_thread_flag(tsk, TIF_SECCOMP); 1092 } else 1093 return -EINVAL; 1094 if (unlikely(!(end - __buf))) 1095 return -EIO; 1096 return end - __buf; 1097 } 1098 1099 static struct file_operations proc_seccomp_operations = { 1100 .read = seccomp_read, 1101 .write = seccomp_write, 1102 }; 1103 #endif /* CONFIG_SECCOMP */ 1104 1105 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) 1106 { 1107 struct inode *inode = dentry->d_inode; 1108 int error = -EACCES; 1109 1110 /* We don't need a base pointer in the /proc filesystem */ 1111 path_release(nd); 1112 1113 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE)) 1114 goto out; 1115 error = proc_check_root(inode); 1116 if (error) 1117 goto out; 1118 1119 error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt); 1120 nd->last_type = LAST_BIND; 1121 out: 1122 return ERR_PTR(error); 1123 } 1124 1125 static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt, 1126 char __user *buffer, int buflen) 1127 { 1128 struct inode * inode; 1129 char *tmp = (char*)__get_free_page(GFP_KERNEL), *path; 1130 int len; 1131 1132 if (!tmp) 1133 return -ENOMEM; 1134 1135 inode = dentry->d_inode; 1136 path = d_path(dentry, mnt, tmp, PAGE_SIZE); 1137 len = PTR_ERR(path); 1138 if (IS_ERR(path)) 1139 goto out; 1140 len = tmp + PAGE_SIZE - 1 - path; 1141 1142 if (len > buflen) 1143 len = buflen; 1144 if (copy_to_user(buffer, path, len)) 1145 len = -EFAULT; 1146 out: 1147 free_page((unsigned long)tmp); 1148 return len; 1149 } 1150 1151 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) 1152 { 1153 int error = -EACCES; 1154 struct inode *inode = dentry->d_inode; 1155 struct dentry *de; 1156 struct vfsmount *mnt = NULL; 1157 1158 lock_kernel(); 1159 1160 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE)) 1161 goto out; 1162 error = proc_check_root(inode); 1163 if (error) 1164 goto out; 1165 1166 error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt); 1167 if (error) 1168 goto out; 1169 1170 error = do_proc_readlink(de, mnt, buffer, buflen); 1171 dput(de); 1172 mntput(mnt); 1173 out: 1174 unlock_kernel(); 1175 return error; 1176 } 1177 1178 static struct inode_operations proc_pid_link_inode_operations = { 1179 .readlink = proc_pid_readlink, 1180 .follow_link = proc_pid_follow_link 1181 }; 1182 1183 #define NUMBUF 10 1184 1185 static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir) 1186 { 1187 struct inode *inode = filp->f_dentry->d_inode; 1188 struct task_struct *p = proc_task(inode); 1189 unsigned int fd, tid, ino; 1190 int retval; 1191 char buf[NUMBUF]; 1192 struct files_struct * files; 1193 struct fdtable *fdt; 1194 1195 retval = -ENOENT; 1196 if (!pid_alive(p)) 1197 goto out; 1198 retval = 0; 1199 tid = p->pid; 1200 1201 fd = filp->f_pos; 1202 switch (fd) { 1203 case 0: 1204 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) 1205 goto out; 1206 filp->f_pos++; 1207 case 1: 1208 ino = fake_ino(tid, PROC_TID_INO); 1209 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) 1210 goto out; 1211 filp->f_pos++; 1212 default: 1213 files = get_files_struct(p); 1214 if (!files) 1215 goto out; 1216 rcu_read_lock(); 1217 fdt = files_fdtable(files); 1218 for (fd = filp->f_pos-2; 1219 fd < fdt->max_fds; 1220 fd++, filp->f_pos++) { 1221 unsigned int i,j; 1222 1223 if (!fcheck_files(files, fd)) 1224 continue; 1225 rcu_read_unlock(); 1226 1227 j = NUMBUF; 1228 i = fd; 1229 do { 1230 j--; 1231 buf[j] = '0' + (i % 10); 1232 i /= 10; 1233 } while (i); 1234 1235 ino = fake_ino(tid, PROC_TID_FD_DIR + fd); 1236 if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) { 1237 rcu_read_lock(); 1238 break; 1239 } 1240 rcu_read_lock(); 1241 } 1242 rcu_read_unlock(); 1243 put_files_struct(files); 1244 } 1245 out: 1246 return retval; 1247 } 1248 1249 static int proc_pident_readdir(struct file *filp, 1250 void *dirent, filldir_t filldir, 1251 struct pid_entry *ents, unsigned int nents) 1252 { 1253 int i; 1254 int pid; 1255 struct dentry *dentry = filp->f_dentry; 1256 struct inode *inode = dentry->d_inode; 1257 struct pid_entry *p; 1258 ino_t ino; 1259 int ret; 1260 1261 ret = -ENOENT; 1262 if (!pid_alive(proc_task(inode))) 1263 goto out; 1264 1265 ret = 0; 1266 pid = proc_task(inode)->pid; 1267 i = filp->f_pos; 1268 switch (i) { 1269 case 0: 1270 ino = inode->i_ino; 1271 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) 1272 goto out; 1273 i++; 1274 filp->f_pos++; 1275 /* fall through */ 1276 case 1: 1277 ino = parent_ino(dentry); 1278 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) 1279 goto out; 1280 i++; 1281 filp->f_pos++; 1282 /* fall through */ 1283 default: 1284 i -= 2; 1285 if (i >= nents) { 1286 ret = 1; 1287 goto out; 1288 } 1289 p = ents + i; 1290 while (p->name) { 1291 if (filldir(dirent, p->name, p->len, filp->f_pos, 1292 fake_ino(pid, p->type), p->mode >> 12) < 0) 1293 goto out; 1294 filp->f_pos++; 1295 p++; 1296 } 1297 } 1298 1299 ret = 1; 1300 out: 1301 return ret; 1302 } 1303 1304 static int proc_tgid_base_readdir(struct file * filp, 1305 void * dirent, filldir_t filldir) 1306 { 1307 return proc_pident_readdir(filp,dirent,filldir, 1308 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); 1309 } 1310 1311 static int proc_tid_base_readdir(struct file * filp, 1312 void * dirent, filldir_t filldir) 1313 { 1314 return proc_pident_readdir(filp,dirent,filldir, 1315 tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); 1316 } 1317 1318 /* building an inode */ 1319 1320 static int task_dumpable(struct task_struct *task) 1321 { 1322 int dumpable = 0; 1323 struct mm_struct *mm; 1324 1325 task_lock(task); 1326 mm = task->mm; 1327 if (mm) 1328 dumpable = mm->dumpable; 1329 task_unlock(task); 1330 if(dumpable == 1) 1331 return 1; 1332 return 0; 1333 } 1334 1335 1336 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino) 1337 { 1338 struct inode * inode; 1339 struct proc_inode *ei; 1340 1341 /* We need a new inode */ 1342 1343 inode = new_inode(sb); 1344 if (!inode) 1345 goto out; 1346 1347 /* Common stuff */ 1348 ei = PROC_I(inode); 1349 ei->task = NULL; 1350 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 1351 inode->i_ino = fake_ino(task->pid, ino); 1352 1353 if (!pid_alive(task)) 1354 goto out_unlock; 1355 1356 /* 1357 * grab the reference to task. 1358 */ 1359 get_task_struct(task); 1360 ei->task = task; 1361 ei->type = ino; 1362 inode->i_uid = 0; 1363 inode->i_gid = 0; 1364 if (ino == PROC_TGID_INO || ino == PROC_TID_INO || task_dumpable(task)) { 1365 inode->i_uid = task->euid; 1366 inode->i_gid = task->egid; 1367 } 1368 security_task_to_inode(task, inode); 1369 1370 out: 1371 return inode; 1372 1373 out_unlock: 1374 ei->pde = NULL; 1375 iput(inode); 1376 return NULL; 1377 } 1378 1379 /* dentry stuff */ 1380 1381 /* 1382 * Exceptional case: normally we are not allowed to unhash a busy 1383 * directory. In this case, however, we can do it - no aliasing problems 1384 * due to the way we treat inodes. 1385 * 1386 * Rewrite the inode's ownerships here because the owning task may have 1387 * performed a setuid(), etc. 1388 */ 1389 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) 1390 { 1391 struct inode *inode = dentry->d_inode; 1392 struct task_struct *task = proc_task(inode); 1393 if (pid_alive(task)) { 1394 if (proc_type(inode) == PROC_TGID_INO || proc_type(inode) == PROC_TID_INO || task_dumpable(task)) { 1395 inode->i_uid = task->euid; 1396 inode->i_gid = task->egid; 1397 } else { 1398 inode->i_uid = 0; 1399 inode->i_gid = 0; 1400 } 1401 security_task_to_inode(task, inode); 1402 return 1; 1403 } 1404 d_drop(dentry); 1405 return 0; 1406 } 1407 1408 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) 1409 { 1410 struct inode *inode = dentry->d_inode; 1411 struct task_struct *task = proc_task(inode); 1412 int fd = proc_type(inode) - PROC_TID_FD_DIR; 1413 struct files_struct *files; 1414 1415 files = get_files_struct(task); 1416 if (files) { 1417 rcu_read_lock(); 1418 if (fcheck_files(files, fd)) { 1419 rcu_read_unlock(); 1420 put_files_struct(files); 1421 if (task_dumpable(task)) { 1422 inode->i_uid = task->euid; 1423 inode->i_gid = task->egid; 1424 } else { 1425 inode->i_uid = 0; 1426 inode->i_gid = 0; 1427 } 1428 security_task_to_inode(task, inode); 1429 return 1; 1430 } 1431 rcu_read_unlock(); 1432 put_files_struct(files); 1433 } 1434 d_drop(dentry); 1435 return 0; 1436 } 1437 1438 static void pid_base_iput(struct dentry *dentry, struct inode *inode) 1439 { 1440 struct task_struct *task = proc_task(inode); 1441 spin_lock(&task->proc_lock); 1442 if (task->proc_dentry == dentry) 1443 task->proc_dentry = NULL; 1444 spin_unlock(&task->proc_lock); 1445 iput(inode); 1446 } 1447 1448 static int pid_delete_dentry(struct dentry * dentry) 1449 { 1450 /* Is the task we represent dead? 1451 * If so, then don't put the dentry on the lru list, 1452 * kill it immediately. 1453 */ 1454 return !pid_alive(proc_task(dentry->d_inode)); 1455 } 1456 1457 static struct dentry_operations tid_fd_dentry_operations = 1458 { 1459 .d_revalidate = tid_fd_revalidate, 1460 .d_delete = pid_delete_dentry, 1461 }; 1462 1463 static struct dentry_operations pid_dentry_operations = 1464 { 1465 .d_revalidate = pid_revalidate, 1466 .d_delete = pid_delete_dentry, 1467 }; 1468 1469 static struct dentry_operations pid_base_dentry_operations = 1470 { 1471 .d_revalidate = pid_revalidate, 1472 .d_iput = pid_base_iput, 1473 .d_delete = pid_delete_dentry, 1474 }; 1475 1476 /* Lookups */ 1477 1478 static unsigned name_to_int(struct dentry *dentry) 1479 { 1480 const char *name = dentry->d_name.name; 1481 int len = dentry->d_name.len; 1482 unsigned n = 0; 1483 1484 if (len > 1 && *name == '0') 1485 goto out; 1486 while (len-- > 0) { 1487 unsigned c = *name++ - '0'; 1488 if (c > 9) 1489 goto out; 1490 if (n >= (~0U-9)/10) 1491 goto out; 1492 n *= 10; 1493 n += c; 1494 } 1495 return n; 1496 out: 1497 return ~0U; 1498 } 1499 1500 /* SMP-safe */ 1501 static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd) 1502 { 1503 struct task_struct *task = proc_task(dir); 1504 unsigned fd = name_to_int(dentry); 1505 struct file * file; 1506 struct files_struct * files; 1507 struct inode *inode; 1508 struct proc_inode *ei; 1509 1510 if (fd == ~0U) 1511 goto out; 1512 if (!pid_alive(task)) 1513 goto out; 1514 1515 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd); 1516 if (!inode) 1517 goto out; 1518 ei = PROC_I(inode); 1519 files = get_files_struct(task); 1520 if (!files) 1521 goto out_unlock; 1522 inode->i_mode = S_IFLNK; 1523 rcu_read_lock(); 1524 file = fcheck_files(files, fd); 1525 if (!file) 1526 goto out_unlock2; 1527 if (file->f_mode & 1) 1528 inode->i_mode |= S_IRUSR | S_IXUSR; 1529 if (file->f_mode & 2) 1530 inode->i_mode |= S_IWUSR | S_IXUSR; 1531 rcu_read_unlock(); 1532 put_files_struct(files); 1533 inode->i_op = &proc_pid_link_inode_operations; 1534 inode->i_size = 64; 1535 ei->op.proc_get_link = proc_fd_link; 1536 dentry->d_op = &tid_fd_dentry_operations; 1537 d_add(dentry, inode); 1538 return NULL; 1539 1540 out_unlock2: 1541 rcu_read_unlock(); 1542 put_files_struct(files); 1543 out_unlock: 1544 iput(inode); 1545 out: 1546 return ERR_PTR(-ENOENT); 1547 } 1548 1549 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir); 1550 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd); 1551 1552 static struct file_operations proc_fd_operations = { 1553 .read = generic_read_dir, 1554 .readdir = proc_readfd, 1555 }; 1556 1557 static struct file_operations proc_task_operations = { 1558 .read = generic_read_dir, 1559 .readdir = proc_task_readdir, 1560 }; 1561 1562 /* 1563 * proc directories can do almost nothing.. 1564 */ 1565 static struct inode_operations proc_fd_inode_operations = { 1566 .lookup = proc_lookupfd, 1567 .permission = proc_permission, 1568 }; 1569 1570 static struct inode_operations proc_task_inode_operations = { 1571 .lookup = proc_task_lookup, 1572 .permission = proc_task_permission, 1573 }; 1574 1575 #ifdef CONFIG_SECURITY 1576 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, 1577 size_t count, loff_t *ppos) 1578 { 1579 struct inode * inode = file->f_dentry->d_inode; 1580 unsigned long page; 1581 ssize_t length; 1582 struct task_struct *task = proc_task(inode); 1583 1584 if (count > PAGE_SIZE) 1585 count = PAGE_SIZE; 1586 if (!(page = __get_free_page(GFP_KERNEL))) 1587 return -ENOMEM; 1588 1589 length = security_getprocattr(task, 1590 (char*)file->f_dentry->d_name.name, 1591 (void*)page, count); 1592 if (length >= 0) 1593 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); 1594 free_page(page); 1595 return length; 1596 } 1597 1598 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, 1599 size_t count, loff_t *ppos) 1600 { 1601 struct inode * inode = file->f_dentry->d_inode; 1602 char *page; 1603 ssize_t length; 1604 struct task_struct *task = proc_task(inode); 1605 1606 if (count > PAGE_SIZE) 1607 count = PAGE_SIZE; 1608 if (*ppos != 0) { 1609 /* No partial writes. */ 1610 return -EINVAL; 1611 } 1612 page = (char*)__get_free_page(GFP_USER); 1613 if (!page) 1614 return -ENOMEM; 1615 length = -EFAULT; 1616 if (copy_from_user(page, buf, count)) 1617 goto out; 1618 1619 length = security_setprocattr(task, 1620 (char*)file->f_dentry->d_name.name, 1621 (void*)page, count); 1622 out: 1623 free_page((unsigned long) page); 1624 return length; 1625 } 1626 1627 static struct file_operations proc_pid_attr_operations = { 1628 .read = proc_pid_attr_read, 1629 .write = proc_pid_attr_write, 1630 }; 1631 1632 static struct file_operations proc_tid_attr_operations; 1633 static struct inode_operations proc_tid_attr_inode_operations; 1634 static struct file_operations proc_tgid_attr_operations; 1635 static struct inode_operations proc_tgid_attr_inode_operations; 1636 #endif 1637 1638 static int get_tid_list(int index, unsigned int *tids, struct inode *dir); 1639 1640 /* SMP-safe */ 1641 static struct dentry *proc_pident_lookup(struct inode *dir, 1642 struct dentry *dentry, 1643 struct pid_entry *ents) 1644 { 1645 struct inode *inode; 1646 int error; 1647 struct task_struct *task = proc_task(dir); 1648 struct pid_entry *p; 1649 struct proc_inode *ei; 1650 1651 error = -ENOENT; 1652 inode = NULL; 1653 1654 if (!pid_alive(task)) 1655 goto out; 1656 1657 for (p = ents; p->name; p++) { 1658 if (p->len != dentry->d_name.len) 1659 continue; 1660 if (!memcmp(dentry->d_name.name, p->name, p->len)) 1661 break; 1662 } 1663 if (!p->name) 1664 goto out; 1665 1666 error = -EINVAL; 1667 inode = proc_pid_make_inode(dir->i_sb, task, p->type); 1668 if (!inode) 1669 goto out; 1670 1671 ei = PROC_I(inode); 1672 inode->i_mode = p->mode; 1673 /* 1674 * Yes, it does not scale. And it should not. Don't add 1675 * new entries into /proc/<tgid>/ without very good reasons. 1676 */ 1677 switch(p->type) { 1678 case PROC_TGID_TASK: 1679 inode->i_nlink = 2 + get_tid_list(2, NULL, dir); 1680 inode->i_op = &proc_task_inode_operations; 1681 inode->i_fop = &proc_task_operations; 1682 break; 1683 case PROC_TID_FD: 1684 case PROC_TGID_FD: 1685 inode->i_nlink = 2; 1686 inode->i_op = &proc_fd_inode_operations; 1687 inode->i_fop = &proc_fd_operations; 1688 break; 1689 case PROC_TID_EXE: 1690 case PROC_TGID_EXE: 1691 inode->i_op = &proc_pid_link_inode_operations; 1692 ei->op.proc_get_link = proc_exe_link; 1693 break; 1694 case PROC_TID_CWD: 1695 case PROC_TGID_CWD: 1696 inode->i_op = &proc_pid_link_inode_operations; 1697 ei->op.proc_get_link = proc_cwd_link; 1698 break; 1699 case PROC_TID_ROOT: 1700 case PROC_TGID_ROOT: 1701 inode->i_op = &proc_pid_link_inode_operations; 1702 ei->op.proc_get_link = proc_root_link; 1703 break; 1704 case PROC_TID_ENVIRON: 1705 case PROC_TGID_ENVIRON: 1706 inode->i_fop = &proc_info_file_operations; 1707 ei->op.proc_read = proc_pid_environ; 1708 break; 1709 case PROC_TID_AUXV: 1710 case PROC_TGID_AUXV: 1711 inode->i_fop = &proc_info_file_operations; 1712 ei->op.proc_read = proc_pid_auxv; 1713 break; 1714 case PROC_TID_STATUS: 1715 case PROC_TGID_STATUS: 1716 inode->i_fop = &proc_info_file_operations; 1717 ei->op.proc_read = proc_pid_status; 1718 break; 1719 case PROC_TID_STAT: 1720 inode->i_fop = &proc_info_file_operations; 1721 ei->op.proc_read = proc_tid_stat; 1722 break; 1723 case PROC_TGID_STAT: 1724 inode->i_fop = &proc_info_file_operations; 1725 ei->op.proc_read = proc_tgid_stat; 1726 break; 1727 case PROC_TID_CMDLINE: 1728 case PROC_TGID_CMDLINE: 1729 inode->i_fop = &proc_info_file_operations; 1730 ei->op.proc_read = proc_pid_cmdline; 1731 break; 1732 case PROC_TID_STATM: 1733 case PROC_TGID_STATM: 1734 inode->i_fop = &proc_info_file_operations; 1735 ei->op.proc_read = proc_pid_statm; 1736 break; 1737 case PROC_TID_MAPS: 1738 case PROC_TGID_MAPS: 1739 inode->i_fop = &proc_maps_operations; 1740 break; 1741 #ifdef CONFIG_NUMA 1742 case PROC_TID_NUMA_MAPS: 1743 case PROC_TGID_NUMA_MAPS: 1744 inode->i_fop = &proc_numa_maps_operations; 1745 break; 1746 #endif 1747 case PROC_TID_MEM: 1748 case PROC_TGID_MEM: 1749 inode->i_op = &proc_mem_inode_operations; 1750 inode->i_fop = &proc_mem_operations; 1751 break; 1752 #ifdef CONFIG_SECCOMP 1753 case PROC_TID_SECCOMP: 1754 case PROC_TGID_SECCOMP: 1755 inode->i_fop = &proc_seccomp_operations; 1756 break; 1757 #endif /* CONFIG_SECCOMP */ 1758 case PROC_TID_MOUNTS: 1759 case PROC_TGID_MOUNTS: 1760 inode->i_fop = &proc_mounts_operations; 1761 break; 1762 #ifdef CONFIG_MMU 1763 case PROC_TID_SMAPS: 1764 case PROC_TGID_SMAPS: 1765 inode->i_fop = &proc_smaps_operations; 1766 break; 1767 #endif 1768 case PROC_TID_MOUNTSTATS: 1769 case PROC_TGID_MOUNTSTATS: 1770 inode->i_fop = &proc_mountstats_operations; 1771 break; 1772 #ifdef CONFIG_SECURITY 1773 case PROC_TID_ATTR: 1774 inode->i_nlink = 2; 1775 inode->i_op = &proc_tid_attr_inode_operations; 1776 inode->i_fop = &proc_tid_attr_operations; 1777 break; 1778 case PROC_TGID_ATTR: 1779 inode->i_nlink = 2; 1780 inode->i_op = &proc_tgid_attr_inode_operations; 1781 inode->i_fop = &proc_tgid_attr_operations; 1782 break; 1783 case PROC_TID_ATTR_CURRENT: 1784 case PROC_TGID_ATTR_CURRENT: 1785 case PROC_TID_ATTR_PREV: 1786 case PROC_TGID_ATTR_PREV: 1787 case PROC_TID_ATTR_EXEC: 1788 case PROC_TGID_ATTR_EXEC: 1789 case PROC_TID_ATTR_FSCREATE: 1790 case PROC_TGID_ATTR_FSCREATE: 1791 inode->i_fop = &proc_pid_attr_operations; 1792 break; 1793 #endif 1794 #ifdef CONFIG_KALLSYMS 1795 case PROC_TID_WCHAN: 1796 case PROC_TGID_WCHAN: 1797 inode->i_fop = &proc_info_file_operations; 1798 ei->op.proc_read = proc_pid_wchan; 1799 break; 1800 #endif 1801 #ifdef CONFIG_SCHEDSTATS 1802 case PROC_TID_SCHEDSTAT: 1803 case PROC_TGID_SCHEDSTAT: 1804 inode->i_fop = &proc_info_file_operations; 1805 ei->op.proc_read = proc_pid_schedstat; 1806 break; 1807 #endif 1808 #ifdef CONFIG_CPUSETS 1809 case PROC_TID_CPUSET: 1810 case PROC_TGID_CPUSET: 1811 inode->i_fop = &proc_cpuset_operations; 1812 break; 1813 #endif 1814 case PROC_TID_OOM_SCORE: 1815 case PROC_TGID_OOM_SCORE: 1816 inode->i_fop = &proc_info_file_operations; 1817 ei->op.proc_read = proc_oom_score; 1818 break; 1819 case PROC_TID_OOM_ADJUST: 1820 case PROC_TGID_OOM_ADJUST: 1821 inode->i_fop = &proc_oom_adjust_operations; 1822 break; 1823 #ifdef CONFIG_AUDITSYSCALL 1824 case PROC_TID_LOGINUID: 1825 case PROC_TGID_LOGINUID: 1826 inode->i_fop = &proc_loginuid_operations; 1827 break; 1828 #endif 1829 default: 1830 printk("procfs: impossible type (%d)",p->type); 1831 iput(inode); 1832 return ERR_PTR(-EINVAL); 1833 } 1834 dentry->d_op = &pid_dentry_operations; 1835 d_add(dentry, inode); 1836 return NULL; 1837 1838 out: 1839 return ERR_PTR(error); 1840 } 1841 1842 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 1843 return proc_pident_lookup(dir, dentry, tgid_base_stuff); 1844 } 1845 1846 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ 1847 return proc_pident_lookup(dir, dentry, tid_base_stuff); 1848 } 1849 1850 static struct file_operations proc_tgid_base_operations = { 1851 .read = generic_read_dir, 1852 .readdir = proc_tgid_base_readdir, 1853 }; 1854 1855 static struct file_operations proc_tid_base_operations = { 1856 .read = generic_read_dir, 1857 .readdir = proc_tid_base_readdir, 1858 }; 1859 1860 static struct inode_operations proc_tgid_base_inode_operations = { 1861 .lookup = proc_tgid_base_lookup, 1862 }; 1863 1864 static struct inode_operations proc_tid_base_inode_operations = { 1865 .lookup = proc_tid_base_lookup, 1866 }; 1867 1868 #ifdef CONFIG_SECURITY 1869 static int proc_tgid_attr_readdir(struct file * filp, 1870 void * dirent, filldir_t filldir) 1871 { 1872 return proc_pident_readdir(filp,dirent,filldir, 1873 tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff)); 1874 } 1875 1876 static int proc_tid_attr_readdir(struct file * filp, 1877 void * dirent, filldir_t filldir) 1878 { 1879 return proc_pident_readdir(filp,dirent,filldir, 1880 tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff)); 1881 } 1882 1883 static struct file_operations proc_tgid_attr_operations = { 1884 .read = generic_read_dir, 1885 .readdir = proc_tgid_attr_readdir, 1886 }; 1887 1888 static struct file_operations proc_tid_attr_operations = { 1889 .read = generic_read_dir, 1890 .readdir = proc_tid_attr_readdir, 1891 }; 1892 1893 static struct dentry *proc_tgid_attr_lookup(struct inode *dir, 1894 struct dentry *dentry, struct nameidata *nd) 1895 { 1896 return proc_pident_lookup(dir, dentry, tgid_attr_stuff); 1897 } 1898 1899 static struct dentry *proc_tid_attr_lookup(struct inode *dir, 1900 struct dentry *dentry, struct nameidata *nd) 1901 { 1902 return proc_pident_lookup(dir, dentry, tid_attr_stuff); 1903 } 1904 1905 static struct inode_operations proc_tgid_attr_inode_operations = { 1906 .lookup = proc_tgid_attr_lookup, 1907 }; 1908 1909 static struct inode_operations proc_tid_attr_inode_operations = { 1910 .lookup = proc_tid_attr_lookup, 1911 }; 1912 #endif 1913 1914 /* 1915 * /proc/self: 1916 */ 1917 static int proc_self_readlink(struct dentry *dentry, char __user *buffer, 1918 int buflen) 1919 { 1920 char tmp[30]; 1921 sprintf(tmp, "%d", current->tgid); 1922 return vfs_readlink(dentry,buffer,buflen,tmp); 1923 } 1924 1925 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) 1926 { 1927 char tmp[30]; 1928 sprintf(tmp, "%d", current->tgid); 1929 return ERR_PTR(vfs_follow_link(nd,tmp)); 1930 } 1931 1932 static struct inode_operations proc_self_inode_operations = { 1933 .readlink = proc_self_readlink, 1934 .follow_link = proc_self_follow_link, 1935 }; 1936 1937 /** 1938 * proc_pid_unhash - Unhash /proc/@pid entry from the dcache. 1939 * @p: task that should be flushed. 1940 * 1941 * Drops the /proc/@pid dcache entry from the hash chains. 1942 * 1943 * Dropping /proc/@pid entries and detach_pid must be synchroneous, 1944 * otherwise e.g. /proc/@pid/exe might point to the wrong executable, 1945 * if the pid value is immediately reused. This is enforced by 1946 * - caller must acquire spin_lock(p->proc_lock) 1947 * - must be called before detach_pid() 1948 * - proc_pid_lookup acquires proc_lock, and checks that 1949 * the target is not dead by looking at the attach count 1950 * of PIDTYPE_PID. 1951 */ 1952 1953 struct dentry *proc_pid_unhash(struct task_struct *p) 1954 { 1955 struct dentry *proc_dentry; 1956 1957 proc_dentry = p->proc_dentry; 1958 if (proc_dentry != NULL) { 1959 1960 spin_lock(&dcache_lock); 1961 spin_lock(&proc_dentry->d_lock); 1962 if (!d_unhashed(proc_dentry)) { 1963 dget_locked(proc_dentry); 1964 __d_drop(proc_dentry); 1965 spin_unlock(&proc_dentry->d_lock); 1966 } else { 1967 spin_unlock(&proc_dentry->d_lock); 1968 proc_dentry = NULL; 1969 } 1970 spin_unlock(&dcache_lock); 1971 } 1972 return proc_dentry; 1973 } 1974 1975 /** 1976 * proc_pid_flush - recover memory used by stale /proc/@pid/x entries 1977 * @proc_dentry: directoy to prune. 1978 * 1979 * Shrink the /proc directory that was used by the just killed thread. 1980 */ 1981 1982 void proc_pid_flush(struct dentry *proc_dentry) 1983 { 1984 might_sleep(); 1985 if(proc_dentry != NULL) { 1986 shrink_dcache_parent(proc_dentry); 1987 dput(proc_dentry); 1988 } 1989 } 1990 1991 /* SMP-safe */ 1992 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 1993 { 1994 struct task_struct *task; 1995 struct inode *inode; 1996 struct proc_inode *ei; 1997 unsigned tgid; 1998 int died; 1999 2000 if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) { 2001 inode = new_inode(dir->i_sb); 2002 if (!inode) 2003 return ERR_PTR(-ENOMEM); 2004 ei = PROC_I(inode); 2005 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; 2006 inode->i_ino = fake_ino(0, PROC_TGID_INO); 2007 ei->pde = NULL; 2008 inode->i_mode = S_IFLNK|S_IRWXUGO; 2009 inode->i_uid = inode->i_gid = 0; 2010 inode->i_size = 64; 2011 inode->i_op = &proc_self_inode_operations; 2012 d_add(dentry, inode); 2013 return NULL; 2014 } 2015 tgid = name_to_int(dentry); 2016 if (tgid == ~0U) 2017 goto out; 2018 2019 read_lock(&tasklist_lock); 2020 task = find_task_by_pid(tgid); 2021 if (task) 2022 get_task_struct(task); 2023 read_unlock(&tasklist_lock); 2024 if (!task) 2025 goto out; 2026 2027 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO); 2028 2029 2030 if (!inode) { 2031 put_task_struct(task); 2032 goto out; 2033 } 2034 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2035 inode->i_op = &proc_tgid_base_inode_operations; 2036 inode->i_fop = &proc_tgid_base_operations; 2037 inode->i_flags|=S_IMMUTABLE; 2038 #ifdef CONFIG_SECURITY 2039 inode->i_nlink = 5; 2040 #else 2041 inode->i_nlink = 4; 2042 #endif 2043 2044 dentry->d_op = &pid_base_dentry_operations; 2045 2046 died = 0; 2047 d_add(dentry, inode); 2048 spin_lock(&task->proc_lock); 2049 task->proc_dentry = dentry; 2050 if (!pid_alive(task)) { 2051 dentry = proc_pid_unhash(task); 2052 died = 1; 2053 } 2054 spin_unlock(&task->proc_lock); 2055 2056 put_task_struct(task); 2057 if (died) { 2058 proc_pid_flush(dentry); 2059 goto out; 2060 } 2061 return NULL; 2062 out: 2063 return ERR_PTR(-ENOENT); 2064 } 2065 2066 /* SMP-safe */ 2067 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) 2068 { 2069 struct task_struct *task; 2070 struct task_struct *leader = proc_task(dir); 2071 struct inode *inode; 2072 unsigned tid; 2073 2074 tid = name_to_int(dentry); 2075 if (tid == ~0U) 2076 goto out; 2077 2078 read_lock(&tasklist_lock); 2079 task = find_task_by_pid(tid); 2080 if (task) 2081 get_task_struct(task); 2082 read_unlock(&tasklist_lock); 2083 if (!task) 2084 goto out; 2085 if (leader->tgid != task->tgid) 2086 goto out_drop_task; 2087 2088 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO); 2089 2090 2091 if (!inode) 2092 goto out_drop_task; 2093 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; 2094 inode->i_op = &proc_tid_base_inode_operations; 2095 inode->i_fop = &proc_tid_base_operations; 2096 inode->i_flags|=S_IMMUTABLE; 2097 #ifdef CONFIG_SECURITY 2098 inode->i_nlink = 4; 2099 #else 2100 inode->i_nlink = 3; 2101 #endif 2102 2103 dentry->d_op = &pid_base_dentry_operations; 2104 2105 d_add(dentry, inode); 2106 2107 put_task_struct(task); 2108 return NULL; 2109 out_drop_task: 2110 put_task_struct(task); 2111 out: 2112 return ERR_PTR(-ENOENT); 2113 } 2114 2115 #define PROC_NUMBUF 10 2116 #define PROC_MAXPIDS 20 2117 2118 /* 2119 * Get a few tgid's to return for filldir - we need to hold the 2120 * tasklist lock while doing this, and we must release it before 2121 * we actually do the filldir itself, so we use a temp buffer.. 2122 */ 2123 static int get_tgid_list(int index, unsigned long version, unsigned int *tgids) 2124 { 2125 struct task_struct *p; 2126 int nr_tgids = 0; 2127 2128 index--; 2129 read_lock(&tasklist_lock); 2130 p = NULL; 2131 if (version) { 2132 p = find_task_by_pid(version); 2133 if (p && !thread_group_leader(p)) 2134 p = NULL; 2135 } 2136 2137 if (p) 2138 index = 0; 2139 else 2140 p = next_task(&init_task); 2141 2142 for ( ; p != &init_task; p = next_task(p)) { 2143 int tgid = p->pid; 2144 if (!pid_alive(p)) 2145 continue; 2146 if (--index >= 0) 2147 continue; 2148 tgids[nr_tgids] = tgid; 2149 nr_tgids++; 2150 if (nr_tgids >= PROC_MAXPIDS) 2151 break; 2152 } 2153 read_unlock(&tasklist_lock); 2154 return nr_tgids; 2155 } 2156 2157 /* 2158 * Get a few tid's to return for filldir - we need to hold the 2159 * tasklist lock while doing this, and we must release it before 2160 * we actually do the filldir itself, so we use a temp buffer.. 2161 */ 2162 static int get_tid_list(int index, unsigned int *tids, struct inode *dir) 2163 { 2164 struct task_struct *leader_task = proc_task(dir); 2165 struct task_struct *task = leader_task; 2166 int nr_tids = 0; 2167 2168 index -= 2; 2169 read_lock(&tasklist_lock); 2170 /* 2171 * The starting point task (leader_task) might be an already 2172 * unlinked task, which cannot be used to access the task-list 2173 * via next_thread(). 2174 */ 2175 if (pid_alive(task)) do { 2176 int tid = task->pid; 2177 2178 if (--index >= 0) 2179 continue; 2180 if (tids != NULL) 2181 tids[nr_tids] = tid; 2182 nr_tids++; 2183 if (nr_tids >= PROC_MAXPIDS) 2184 break; 2185 } while ((task = next_thread(task)) != leader_task); 2186 read_unlock(&tasklist_lock); 2187 return nr_tids; 2188 } 2189 2190 /* for the /proc/ directory itself, after non-process stuff has been done */ 2191 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) 2192 { 2193 unsigned int tgid_array[PROC_MAXPIDS]; 2194 char buf[PROC_NUMBUF]; 2195 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; 2196 unsigned int nr_tgids, i; 2197 int next_tgid; 2198 2199 if (!nr) { 2200 ino_t ino = fake_ino(0,PROC_TGID_INO); 2201 if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0) 2202 return 0; 2203 filp->f_pos++; 2204 nr++; 2205 } 2206 2207 /* f_version caches the tgid value that the last readdir call couldn't 2208 * return. lseek aka telldir automagically resets f_version to 0. 2209 */ 2210 next_tgid = filp->f_version; 2211 filp->f_version = 0; 2212 for (;;) { 2213 nr_tgids = get_tgid_list(nr, next_tgid, tgid_array); 2214 if (!nr_tgids) { 2215 /* no more entries ! */ 2216 break; 2217 } 2218 next_tgid = 0; 2219 2220 /* do not use the last found pid, reserve it for next_tgid */ 2221 if (nr_tgids == PROC_MAXPIDS) { 2222 nr_tgids--; 2223 next_tgid = tgid_array[nr_tgids]; 2224 } 2225 2226 for (i=0;i<nr_tgids;i++) { 2227 int tgid = tgid_array[i]; 2228 ino_t ino = fake_ino(tgid,PROC_TGID_INO); 2229 unsigned long j = PROC_NUMBUF; 2230 2231 do 2232 buf[--j] = '0' + (tgid % 10); 2233 while ((tgid /= 10) != 0); 2234 2235 if (filldir(dirent, buf+j, PROC_NUMBUF-j, filp->f_pos, ino, DT_DIR) < 0) { 2236 /* returning this tgid failed, save it as the first 2237 * pid for the next readir call */ 2238 filp->f_version = tgid_array[i]; 2239 goto out; 2240 } 2241 filp->f_pos++; 2242 nr++; 2243 } 2244 } 2245 out: 2246 return 0; 2247 } 2248 2249 /* for the /proc/TGID/task/ directories */ 2250 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) 2251 { 2252 unsigned int tid_array[PROC_MAXPIDS]; 2253 char buf[PROC_NUMBUF]; 2254 unsigned int nr_tids, i; 2255 struct dentry *dentry = filp->f_dentry; 2256 struct inode *inode = dentry->d_inode; 2257 int retval = -ENOENT; 2258 ino_t ino; 2259 unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */ 2260 2261 if (!pid_alive(proc_task(inode))) 2262 goto out; 2263 retval = 0; 2264 2265 switch (pos) { 2266 case 0: 2267 ino = inode->i_ino; 2268 if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0) 2269 goto out; 2270 pos++; 2271 /* fall through */ 2272 case 1: 2273 ino = parent_ino(dentry); 2274 if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0) 2275 goto out; 2276 pos++; 2277 /* fall through */ 2278 } 2279 2280 nr_tids = get_tid_list(pos, tid_array, inode); 2281 inode->i_nlink = pos + nr_tids; 2282 2283 for (i = 0; i < nr_tids; i++) { 2284 unsigned long j = PROC_NUMBUF; 2285 int tid = tid_array[i]; 2286 2287 ino = fake_ino(tid,PROC_TID_INO); 2288 2289 do 2290 buf[--j] = '0' + (tid % 10); 2291 while ((tid /= 10) != 0); 2292 2293 if (filldir(dirent, buf+j, PROC_NUMBUF-j, pos, ino, DT_DIR) < 0) 2294 break; 2295 pos++; 2296 } 2297 out: 2298 filp->f_pos = pos; 2299 return retval; 2300 } 2301