1 /* Common capabilities, needed by capability.o. 2 * 3 * This program is free software; you can redistribute it and/or modify 4 * it under the terms of the GNU General Public License as published by 5 * the Free Software Foundation; either version 2 of the License, or 6 * (at your option) any later version. 7 * 8 */ 9 10 #include <linux/capability.h> 11 #include <linux/audit.h> 12 #include <linux/init.h> 13 #include <linux/kernel.h> 14 #include <linux/lsm_hooks.h> 15 #include <linux/file.h> 16 #include <linux/mm.h> 17 #include <linux/mman.h> 18 #include <linux/pagemap.h> 19 #include <linux/swap.h> 20 #include <linux/skbuff.h> 21 #include <linux/netlink.h> 22 #include <linux/ptrace.h> 23 #include <linux/xattr.h> 24 #include <linux/hugetlb.h> 25 #include <linux/mount.h> 26 #include <linux/sched.h> 27 #include <linux/prctl.h> 28 #include <linux/securebits.h> 29 #include <linux/user_namespace.h> 30 #include <linux/binfmts.h> 31 #include <linux/personality.h> 32 33 /* 34 * If a non-root user executes a setuid-root binary in 35 * !secure(SECURE_NOROOT) mode, then we raise capabilities. 36 * However if fE is also set, then the intent is for only 37 * the file capabilities to be applied, and the setuid-root 38 * bit is left on either to change the uid (plausible) or 39 * to get full privilege on a kernel without file capabilities 40 * support. So in that case we do not raise capabilities. 41 * 42 * Warn if that happens, once per boot. 43 */ 44 static void warn_setuid_and_fcaps_mixed(const char *fname) 45 { 46 static int warned; 47 if (!warned) { 48 printk(KERN_INFO "warning: `%s' has both setuid-root and" 49 " effective capabilities. Therefore not raising all" 50 " capabilities.\n", fname); 51 warned = 1; 52 } 53 } 54 55 /** 56 * cap_capable - Determine whether a task has a particular effective capability 57 * @cred: The credentials to use 58 * @ns: The user namespace in which we need the capability 59 * @cap: The capability to check for 60 * @opts: Bitmask of options defined in include/linux/security.h 61 * 62 * Determine whether the nominated task has the specified capability amongst 63 * its effective set, returning 0 if it does, -ve if it does not. 64 * 65 * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable() 66 * and has_capability() functions. That is, it has the reverse semantics: 67 * cap_has_capability() returns 0 when a task has a capability, but the 68 * kernel's capable() and has_capability() returns 1 for this case. 69 */ 70 int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, 71 int cap, unsigned int opts) 72 { 73 struct user_namespace *ns = targ_ns; 74 75 /* See if cred has the capability in the target user namespace 76 * by examining the target user namespace and all of the target 77 * user namespace's parents. 78 */ 79 for (;;) { 80 /* Do we have the necessary capabilities? */ 81 if (ns == cred->user_ns) 82 return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; 83 84 /* 85 * If we're already at a lower level than we're looking for, 86 * we're done searching. 87 */ 88 if (ns->level <= cred->user_ns->level) 89 return -EPERM; 90 91 /* 92 * The owner of the user namespace in the parent of the 93 * user namespace has all caps. 94 */ 95 if ((ns->parent == cred->user_ns) && uid_eq(ns->owner, cred->euid)) 96 return 0; 97 98 /* 99 * If you have a capability in a parent user ns, then you have 100 * it over all children user namespaces as well. 101 */ 102 ns = ns->parent; 103 } 104 105 /* We never get here */ 106 } 107 108 /** 109 * cap_settime - Determine whether the current process may set the system clock 110 * @ts: The time to set 111 * @tz: The timezone to set 112 * 113 * Determine whether the current process may set the system clock and timezone 114 * information, returning 0 if permission granted, -ve if denied. 115 */ 116 int cap_settime(const struct timespec64 *ts, const struct timezone *tz) 117 { 118 if (!capable(CAP_SYS_TIME)) 119 return -EPERM; 120 return 0; 121 } 122 123 /** 124 * cap_ptrace_access_check - Determine whether the current process may access 125 * another 126 * @child: The process to be accessed 127 * @mode: The mode of attachment. 128 * 129 * If we are in the same or an ancestor user_ns and have all the target 130 * task's capabilities, then ptrace access is allowed. 131 * If we have the ptrace capability to the target user_ns, then ptrace 132 * access is allowed. 133 * Else denied. 134 * 135 * Determine whether a process may access another, returning 0 if permission 136 * granted, -ve if denied. 137 */ 138 int cap_ptrace_access_check(struct task_struct *child, unsigned int mode) 139 { 140 int ret = 0; 141 const struct cred *cred, *child_cred; 142 const kernel_cap_t *caller_caps; 143 144 rcu_read_lock(); 145 cred = current_cred(); 146 child_cred = __task_cred(child); 147 if (mode & PTRACE_MODE_FSCREDS) 148 caller_caps = &cred->cap_effective; 149 else 150 caller_caps = &cred->cap_permitted; 151 if (cred->user_ns == child_cred->user_ns && 152 cap_issubset(child_cred->cap_permitted, *caller_caps)) 153 goto out; 154 if (ns_capable(child_cred->user_ns, CAP_SYS_PTRACE)) 155 goto out; 156 ret = -EPERM; 157 out: 158 rcu_read_unlock(); 159 return ret; 160 } 161 162 /** 163 * cap_ptrace_traceme - Determine whether another process may trace the current 164 * @parent: The task proposed to be the tracer 165 * 166 * If parent is in the same or an ancestor user_ns and has all current's 167 * capabilities, then ptrace access is allowed. 168 * If parent has the ptrace capability to current's user_ns, then ptrace 169 * access is allowed. 170 * Else denied. 171 * 172 * Determine whether the nominated task is permitted to trace the current 173 * process, returning 0 if permission is granted, -ve if denied. 174 */ 175 int cap_ptrace_traceme(struct task_struct *parent) 176 { 177 int ret = 0; 178 const struct cred *cred, *child_cred; 179 180 rcu_read_lock(); 181 cred = __task_cred(parent); 182 child_cred = current_cred(); 183 if (cred->user_ns == child_cred->user_ns && 184 cap_issubset(child_cred->cap_permitted, cred->cap_permitted)) 185 goto out; 186 if (has_ns_capability(parent, child_cred->user_ns, CAP_SYS_PTRACE)) 187 goto out; 188 ret = -EPERM; 189 out: 190 rcu_read_unlock(); 191 return ret; 192 } 193 194 /** 195 * cap_capget - Retrieve a task's capability sets 196 * @target: The task from which to retrieve the capability sets 197 * @effective: The place to record the effective set 198 * @inheritable: The place to record the inheritable set 199 * @permitted: The place to record the permitted set 200 * 201 * This function retrieves the capabilities of the nominated task and returns 202 * them to the caller. 203 */ 204 int cap_capget(struct task_struct *target, kernel_cap_t *effective, 205 kernel_cap_t *inheritable, kernel_cap_t *permitted) 206 { 207 const struct cred *cred; 208 209 /* Derived from kernel/capability.c:sys_capget. */ 210 rcu_read_lock(); 211 cred = __task_cred(target); 212 *effective = cred->cap_effective; 213 *inheritable = cred->cap_inheritable; 214 *permitted = cred->cap_permitted; 215 rcu_read_unlock(); 216 return 0; 217 } 218 219 /* 220 * Determine whether the inheritable capabilities are limited to the old 221 * permitted set. Returns 1 if they are limited, 0 if they are not. 222 */ 223 static inline int cap_inh_is_capped(void) 224 { 225 /* they are so limited unless the current task has the CAP_SETPCAP 226 * capability 227 */ 228 if (cap_capable(current_cred(), current_cred()->user_ns, 229 CAP_SETPCAP, CAP_OPT_NONE) == 0) 230 return 0; 231 return 1; 232 } 233 234 /** 235 * cap_capset - Validate and apply proposed changes to current's capabilities 236 * @new: The proposed new credentials; alterations should be made here 237 * @old: The current task's current credentials 238 * @effective: A pointer to the proposed new effective capabilities set 239 * @inheritable: A pointer to the proposed new inheritable capabilities set 240 * @permitted: A pointer to the proposed new permitted capabilities set 241 * 242 * This function validates and applies a proposed mass change to the current 243 * process's capability sets. The changes are made to the proposed new 244 * credentials, and assuming no error, will be committed by the caller of LSM. 245 */ 246 int cap_capset(struct cred *new, 247 const struct cred *old, 248 const kernel_cap_t *effective, 249 const kernel_cap_t *inheritable, 250 const kernel_cap_t *permitted) 251 { 252 if (cap_inh_is_capped() && 253 !cap_issubset(*inheritable, 254 cap_combine(old->cap_inheritable, 255 old->cap_permitted))) 256 /* incapable of using this inheritable set */ 257 return -EPERM; 258 259 if (!cap_issubset(*inheritable, 260 cap_combine(old->cap_inheritable, 261 old->cap_bset))) 262 /* no new pI capabilities outside bounding set */ 263 return -EPERM; 264 265 /* verify restrictions on target's new Permitted set */ 266 if (!cap_issubset(*permitted, old->cap_permitted)) 267 return -EPERM; 268 269 /* verify the _new_Effective_ is a subset of the _new_Permitted_ */ 270 if (!cap_issubset(*effective, *permitted)) 271 return -EPERM; 272 273 new->cap_effective = *effective; 274 new->cap_inheritable = *inheritable; 275 new->cap_permitted = *permitted; 276 277 /* 278 * Mask off ambient bits that are no longer both permitted and 279 * inheritable. 280 */ 281 new->cap_ambient = cap_intersect(new->cap_ambient, 282 cap_intersect(*permitted, 283 *inheritable)); 284 if (WARN_ON(!cap_ambient_invariant_ok(new))) 285 return -EINVAL; 286 return 0; 287 } 288 289 /** 290 * cap_inode_need_killpriv - Determine if inode change affects privileges 291 * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV 292 * 293 * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV 294 * affects the security markings on that inode, and if it is, should 295 * inode_killpriv() be invoked or the change rejected. 296 * 297 * Returns 1 if security.capability has a value, meaning inode_killpriv() 298 * is required, 0 otherwise, meaning inode_killpriv() is not required. 299 */ 300 int cap_inode_need_killpriv(struct dentry *dentry) 301 { 302 struct inode *inode = d_backing_inode(dentry); 303 int error; 304 305 error = __vfs_getxattr(dentry, inode, XATTR_NAME_CAPS, NULL, 0); 306 return error > 0; 307 } 308 309 /** 310 * cap_inode_killpriv - Erase the security markings on an inode 311 * @dentry: The inode/dentry to alter 312 * 313 * Erase the privilege-enhancing security markings on an inode. 314 * 315 * Returns 0 if successful, -ve on error. 316 */ 317 int cap_inode_killpriv(struct dentry *dentry) 318 { 319 int error; 320 321 error = __vfs_removexattr(dentry, XATTR_NAME_CAPS); 322 if (error == -EOPNOTSUPP) 323 error = 0; 324 return error; 325 } 326 327 static bool rootid_owns_currentns(kuid_t kroot) 328 { 329 struct user_namespace *ns; 330 331 if (!uid_valid(kroot)) 332 return false; 333 334 for (ns = current_user_ns(); ; ns = ns->parent) { 335 if (from_kuid(ns, kroot) == 0) 336 return true; 337 if (ns == &init_user_ns) 338 break; 339 } 340 341 return false; 342 } 343 344 static __u32 sansflags(__u32 m) 345 { 346 return m & ~VFS_CAP_FLAGS_EFFECTIVE; 347 } 348 349 static bool is_v2header(size_t size, const struct vfs_cap_data *cap) 350 { 351 if (size != XATTR_CAPS_SZ_2) 352 return false; 353 return sansflags(le32_to_cpu(cap->magic_etc)) == VFS_CAP_REVISION_2; 354 } 355 356 static bool is_v3header(size_t size, const struct vfs_cap_data *cap) 357 { 358 if (size != XATTR_CAPS_SZ_3) 359 return false; 360 return sansflags(le32_to_cpu(cap->magic_etc)) == VFS_CAP_REVISION_3; 361 } 362 363 /* 364 * getsecurity: We are called for security.* before any attempt to read the 365 * xattr from the inode itself. 366 * 367 * This gives us a chance to read the on-disk value and convert it. If we 368 * return -EOPNOTSUPP, then vfs_getxattr() will call the i_op handler. 369 * 370 * Note we are not called by vfs_getxattr_alloc(), but that is only called 371 * by the integrity subsystem, which really wants the unconverted values - 372 * so that's good. 373 */ 374 int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer, 375 bool alloc) 376 { 377 int size, ret; 378 kuid_t kroot; 379 uid_t root, mappedroot; 380 char *tmpbuf = NULL; 381 struct vfs_cap_data *cap; 382 struct vfs_ns_cap_data *nscap; 383 struct dentry *dentry; 384 struct user_namespace *fs_ns; 385 386 if (strcmp(name, "capability") != 0) 387 return -EOPNOTSUPP; 388 389 dentry = d_find_any_alias(inode); 390 if (!dentry) 391 return -EINVAL; 392 393 size = sizeof(struct vfs_ns_cap_data); 394 ret = (int) vfs_getxattr_alloc(dentry, XATTR_NAME_CAPS, 395 &tmpbuf, size, GFP_NOFS); 396 dput(dentry); 397 398 if (ret < 0) 399 return ret; 400 401 fs_ns = inode->i_sb->s_user_ns; 402 cap = (struct vfs_cap_data *) tmpbuf; 403 if (is_v2header((size_t) ret, cap)) { 404 /* If this is sizeof(vfs_cap_data) then we're ok with the 405 * on-disk value, so return that. */ 406 if (alloc) 407 *buffer = tmpbuf; 408 else 409 kfree(tmpbuf); 410 return ret; 411 } else if (!is_v3header((size_t) ret, cap)) { 412 kfree(tmpbuf); 413 return -EINVAL; 414 } 415 416 nscap = (struct vfs_ns_cap_data *) tmpbuf; 417 root = le32_to_cpu(nscap->rootid); 418 kroot = make_kuid(fs_ns, root); 419 420 /* If the root kuid maps to a valid uid in current ns, then return 421 * this as a nscap. */ 422 mappedroot = from_kuid(current_user_ns(), kroot); 423 if (mappedroot != (uid_t)-1 && mappedroot != (uid_t)0) { 424 if (alloc) { 425 *buffer = tmpbuf; 426 nscap->rootid = cpu_to_le32(mappedroot); 427 } else 428 kfree(tmpbuf); 429 return size; 430 } 431 432 if (!rootid_owns_currentns(kroot)) { 433 kfree(tmpbuf); 434 return -EOPNOTSUPP; 435 } 436 437 /* This comes from a parent namespace. Return as a v2 capability */ 438 size = sizeof(struct vfs_cap_data); 439 if (alloc) { 440 *buffer = kmalloc(size, GFP_ATOMIC); 441 if (*buffer) { 442 struct vfs_cap_data *cap = *buffer; 443 __le32 nsmagic, magic; 444 magic = VFS_CAP_REVISION_2; 445 nsmagic = le32_to_cpu(nscap->magic_etc); 446 if (nsmagic & VFS_CAP_FLAGS_EFFECTIVE) 447 magic |= VFS_CAP_FLAGS_EFFECTIVE; 448 memcpy(&cap->data, &nscap->data, sizeof(__le32) * 2 * VFS_CAP_U32); 449 cap->magic_etc = cpu_to_le32(magic); 450 } else { 451 size = -ENOMEM; 452 } 453 } 454 kfree(tmpbuf); 455 return size; 456 } 457 458 static kuid_t rootid_from_xattr(const void *value, size_t size, 459 struct user_namespace *task_ns) 460 { 461 const struct vfs_ns_cap_data *nscap = value; 462 uid_t rootid = 0; 463 464 if (size == XATTR_CAPS_SZ_3) 465 rootid = le32_to_cpu(nscap->rootid); 466 467 return make_kuid(task_ns, rootid); 468 } 469 470 static bool validheader(size_t size, const struct vfs_cap_data *cap) 471 { 472 return is_v2header(size, cap) || is_v3header(size, cap); 473 } 474 475 /* 476 * User requested a write of security.capability. If needed, update the 477 * xattr to change from v2 to v3, or to fixup the v3 rootid. 478 * 479 * If all is ok, we return the new size, on error return < 0. 480 */ 481 int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size) 482 { 483 struct vfs_ns_cap_data *nscap; 484 uid_t nsrootid; 485 const struct vfs_cap_data *cap = *ivalue; 486 __u32 magic, nsmagic; 487 struct inode *inode = d_backing_inode(dentry); 488 struct user_namespace *task_ns = current_user_ns(), 489 *fs_ns = inode->i_sb->s_user_ns; 490 kuid_t rootid; 491 size_t newsize; 492 493 if (!*ivalue) 494 return -EINVAL; 495 if (!validheader(size, cap)) 496 return -EINVAL; 497 if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP)) 498 return -EPERM; 499 if (size == XATTR_CAPS_SZ_2) 500 if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP)) 501 /* user is privileged, just write the v2 */ 502 return size; 503 504 rootid = rootid_from_xattr(*ivalue, size, task_ns); 505 if (!uid_valid(rootid)) 506 return -EINVAL; 507 508 nsrootid = from_kuid(fs_ns, rootid); 509 if (nsrootid == -1) 510 return -EINVAL; 511 512 newsize = sizeof(struct vfs_ns_cap_data); 513 nscap = kmalloc(newsize, GFP_ATOMIC); 514 if (!nscap) 515 return -ENOMEM; 516 nscap->rootid = cpu_to_le32(nsrootid); 517 nsmagic = VFS_CAP_REVISION_3; 518 magic = le32_to_cpu(cap->magic_etc); 519 if (magic & VFS_CAP_FLAGS_EFFECTIVE) 520 nsmagic |= VFS_CAP_FLAGS_EFFECTIVE; 521 nscap->magic_etc = cpu_to_le32(nsmagic); 522 memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32); 523 524 kvfree(*ivalue); 525 *ivalue = nscap; 526 return newsize; 527 } 528 529 /* 530 * Calculate the new process capability sets from the capability sets attached 531 * to a file. 532 */ 533 static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps, 534 struct linux_binprm *bprm, 535 bool *effective, 536 bool *has_fcap) 537 { 538 struct cred *new = bprm->cred; 539 unsigned i; 540 int ret = 0; 541 542 if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE) 543 *effective = true; 544 545 if (caps->magic_etc & VFS_CAP_REVISION_MASK) 546 *has_fcap = true; 547 548 CAP_FOR_EACH_U32(i) { 549 __u32 permitted = caps->permitted.cap[i]; 550 __u32 inheritable = caps->inheritable.cap[i]; 551 552 /* 553 * pP' = (X & fP) | (pI & fI) 554 * The addition of pA' is handled later. 555 */ 556 new->cap_permitted.cap[i] = 557 (new->cap_bset.cap[i] & permitted) | 558 (new->cap_inheritable.cap[i] & inheritable); 559 560 if (permitted & ~new->cap_permitted.cap[i]) 561 /* insufficient to execute correctly */ 562 ret = -EPERM; 563 } 564 565 /* 566 * For legacy apps, with no internal support for recognizing they 567 * do not have enough capabilities, we return an error if they are 568 * missing some "forced" (aka file-permitted) capabilities. 569 */ 570 return *effective ? ret : 0; 571 } 572 573 /* 574 * Extract the on-exec-apply capability sets for an executable file. 575 */ 576 int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps) 577 { 578 struct inode *inode = d_backing_inode(dentry); 579 __u32 magic_etc; 580 unsigned tocopy, i; 581 int size; 582 struct vfs_ns_cap_data data, *nscaps = &data; 583 struct vfs_cap_data *caps = (struct vfs_cap_data *) &data; 584 kuid_t rootkuid; 585 struct user_namespace *fs_ns; 586 587 memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data)); 588 589 if (!inode) 590 return -ENODATA; 591 592 fs_ns = inode->i_sb->s_user_ns; 593 size = __vfs_getxattr((struct dentry *)dentry, inode, 594 XATTR_NAME_CAPS, &data, XATTR_CAPS_SZ); 595 if (size == -ENODATA || size == -EOPNOTSUPP) 596 /* no data, that's ok */ 597 return -ENODATA; 598 599 if (size < 0) 600 return size; 601 602 if (size < sizeof(magic_etc)) 603 return -EINVAL; 604 605 cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps->magic_etc); 606 607 rootkuid = make_kuid(fs_ns, 0); 608 switch (magic_etc & VFS_CAP_REVISION_MASK) { 609 case VFS_CAP_REVISION_1: 610 if (size != XATTR_CAPS_SZ_1) 611 return -EINVAL; 612 tocopy = VFS_CAP_U32_1; 613 break; 614 case VFS_CAP_REVISION_2: 615 if (size != XATTR_CAPS_SZ_2) 616 return -EINVAL; 617 tocopy = VFS_CAP_U32_2; 618 break; 619 case VFS_CAP_REVISION_3: 620 if (size != XATTR_CAPS_SZ_3) 621 return -EINVAL; 622 tocopy = VFS_CAP_U32_3; 623 rootkuid = make_kuid(fs_ns, le32_to_cpu(nscaps->rootid)); 624 break; 625 626 default: 627 return -EINVAL; 628 } 629 /* Limit the caps to the mounter of the filesystem 630 * or the more limited uid specified in the xattr. 631 */ 632 if (!rootid_owns_currentns(rootkuid)) 633 return -ENODATA; 634 635 CAP_FOR_EACH_U32(i) { 636 if (i >= tocopy) 637 break; 638 cpu_caps->permitted.cap[i] = le32_to_cpu(caps->data[i].permitted); 639 cpu_caps->inheritable.cap[i] = le32_to_cpu(caps->data[i].inheritable); 640 } 641 642 cpu_caps->permitted.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK; 643 cpu_caps->inheritable.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK; 644 645 cpu_caps->rootid = rootkuid; 646 647 return 0; 648 } 649 650 /* 651 * Attempt to get the on-exec apply capability sets for an executable file from 652 * its xattrs and, if present, apply them to the proposed credentials being 653 * constructed by execve(). 654 */ 655 static int get_file_caps(struct linux_binprm *bprm, bool *effective, bool *has_fcap) 656 { 657 int rc = 0; 658 struct cpu_vfs_cap_data vcaps; 659 660 cap_clear(bprm->cred->cap_permitted); 661 662 if (!file_caps_enabled) 663 return 0; 664 665 if (!mnt_may_suid(bprm->file->f_path.mnt)) 666 return 0; 667 668 /* 669 * This check is redundant with mnt_may_suid() but is kept to make 670 * explicit that capability bits are limited to s_user_ns and its 671 * descendants. 672 */ 673 if (!current_in_userns(bprm->file->f_path.mnt->mnt_sb->s_user_ns)) 674 return 0; 675 676 rc = get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps); 677 if (rc < 0) { 678 if (rc == -EINVAL) 679 printk(KERN_NOTICE "Invalid argument reading file caps for %s\n", 680 bprm->filename); 681 else if (rc == -ENODATA) 682 rc = 0; 683 goto out; 684 } 685 686 rc = bprm_caps_from_vfs_caps(&vcaps, bprm, effective, has_fcap); 687 688 out: 689 if (rc) 690 cap_clear(bprm->cred->cap_permitted); 691 692 return rc; 693 } 694 695 static inline bool root_privileged(void) { return !issecure(SECURE_NOROOT); } 696 697 static inline bool __is_real(kuid_t uid, struct cred *cred) 698 { return uid_eq(cred->uid, uid); } 699 700 static inline bool __is_eff(kuid_t uid, struct cred *cred) 701 { return uid_eq(cred->euid, uid); } 702 703 static inline bool __is_suid(kuid_t uid, struct cred *cred) 704 { return !__is_real(uid, cred) && __is_eff(uid, cred); } 705 706 /* 707 * handle_privileged_root - Handle case of privileged root 708 * @bprm: The execution parameters, including the proposed creds 709 * @has_fcap: Are any file capabilities set? 710 * @effective: Do we have effective root privilege? 711 * @root_uid: This namespace' root UID WRT initial USER namespace 712 * 713 * Handle the case where root is privileged and hasn't been neutered by 714 * SECURE_NOROOT. If file capabilities are set, they won't be combined with 715 * set UID root and nothing is changed. If we are root, cap_permitted is 716 * updated. If we have become set UID root, the effective bit is set. 717 */ 718 static void handle_privileged_root(struct linux_binprm *bprm, bool has_fcap, 719 bool *effective, kuid_t root_uid) 720 { 721 const struct cred *old = current_cred(); 722 struct cred *new = bprm->cred; 723 724 if (!root_privileged()) 725 return; 726 /* 727 * If the legacy file capability is set, then don't set privs 728 * for a setuid root binary run by a non-root user. Do set it 729 * for a root user just to cause least surprise to an admin. 730 */ 731 if (has_fcap && __is_suid(root_uid, new)) { 732 warn_setuid_and_fcaps_mixed(bprm->filename); 733 return; 734 } 735 /* 736 * To support inheritance of root-permissions and suid-root 737 * executables under compatibility mode, we override the 738 * capability sets for the file. 739 */ 740 if (__is_eff(root_uid, new) || __is_real(root_uid, new)) { 741 /* pP' = (cap_bset & ~0) | (pI & ~0) */ 742 new->cap_permitted = cap_combine(old->cap_bset, 743 old->cap_inheritable); 744 } 745 /* 746 * If only the real uid is 0, we do not set the effective bit. 747 */ 748 if (__is_eff(root_uid, new)) 749 *effective = true; 750 } 751 752 #define __cap_gained(field, target, source) \ 753 !cap_issubset(target->cap_##field, source->cap_##field) 754 #define __cap_grew(target, source, cred) \ 755 !cap_issubset(cred->cap_##target, cred->cap_##source) 756 #define __cap_full(field, cred) \ 757 cap_issubset(CAP_FULL_SET, cred->cap_##field) 758 759 static inline bool __is_setuid(struct cred *new, const struct cred *old) 760 { return !uid_eq(new->euid, old->uid); } 761 762 static inline bool __is_setgid(struct cred *new, const struct cred *old) 763 { return !gid_eq(new->egid, old->gid); } 764 765 /* 766 * 1) Audit candidate if current->cap_effective is set 767 * 768 * We do not bother to audit if 3 things are true: 769 * 1) cap_effective has all caps 770 * 2) we became root *OR* are were already root 771 * 3) root is supposed to have all caps (SECURE_NOROOT) 772 * Since this is just a normal root execing a process. 773 * 774 * Number 1 above might fail if you don't have a full bset, but I think 775 * that is interesting information to audit. 776 * 777 * A number of other conditions require logging: 778 * 2) something prevented setuid root getting all caps 779 * 3) non-setuid root gets fcaps 780 * 4) non-setuid root gets ambient 781 */ 782 static inline bool nonroot_raised_pE(struct cred *new, const struct cred *old, 783 kuid_t root, bool has_fcap) 784 { 785 bool ret = false; 786 787 if ((__cap_grew(effective, ambient, new) && 788 !(__cap_full(effective, new) && 789 (__is_eff(root, new) || __is_real(root, new)) && 790 root_privileged())) || 791 (root_privileged() && 792 __is_suid(root, new) && 793 !__cap_full(effective, new)) || 794 (!__is_setuid(new, old) && 795 ((has_fcap && 796 __cap_gained(permitted, new, old)) || 797 __cap_gained(ambient, new, old)))) 798 799 ret = true; 800 801 return ret; 802 } 803 804 /** 805 * cap_bprm_set_creds - Set up the proposed credentials for execve(). 806 * @bprm: The execution parameters, including the proposed creds 807 * 808 * Set up the proposed credentials for a new execution context being 809 * constructed by execve(). The proposed creds in @bprm->cred is altered, 810 * which won't take effect immediately. Returns 0 if successful, -ve on error. 811 */ 812 int cap_bprm_set_creds(struct linux_binprm *bprm) 813 { 814 const struct cred *old = current_cred(); 815 struct cred *new = bprm->cred; 816 bool effective = false, has_fcap = false, is_setid; 817 int ret; 818 kuid_t root_uid; 819 820 if (WARN_ON(!cap_ambient_invariant_ok(old))) 821 return -EPERM; 822 823 ret = get_file_caps(bprm, &effective, &has_fcap); 824 if (ret < 0) 825 return ret; 826 827 root_uid = make_kuid(new->user_ns, 0); 828 829 handle_privileged_root(bprm, has_fcap, &effective, root_uid); 830 831 /* if we have fs caps, clear dangerous personality flags */ 832 if (__cap_gained(permitted, new, old)) 833 bprm->per_clear |= PER_CLEAR_ON_SETID; 834 835 /* Don't let someone trace a set[ug]id/setpcap binary with the revised 836 * credentials unless they have the appropriate permit. 837 * 838 * In addition, if NO_NEW_PRIVS, then ensure we get no new privs. 839 */ 840 is_setid = __is_setuid(new, old) || __is_setgid(new, old); 841 842 if ((is_setid || __cap_gained(permitted, new, old)) && 843 ((bprm->unsafe & ~LSM_UNSAFE_PTRACE) || 844 !ptracer_capable(current, new->user_ns))) { 845 /* downgrade; they get no more than they had, and maybe less */ 846 if (!ns_capable(new->user_ns, CAP_SETUID) || 847 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) { 848 new->euid = new->uid; 849 new->egid = new->gid; 850 } 851 new->cap_permitted = cap_intersect(new->cap_permitted, 852 old->cap_permitted); 853 } 854 855 new->suid = new->fsuid = new->euid; 856 new->sgid = new->fsgid = new->egid; 857 858 /* File caps or setid cancels ambient. */ 859 if (has_fcap || is_setid) 860 cap_clear(new->cap_ambient); 861 862 /* 863 * Now that we've computed pA', update pP' to give: 864 * pP' = (X & fP) | (pI & fI) | pA' 865 */ 866 new->cap_permitted = cap_combine(new->cap_permitted, new->cap_ambient); 867 868 /* 869 * Set pE' = (fE ? pP' : pA'). Because pA' is zero if fE is set, 870 * this is the same as pE' = (fE ? pP' : 0) | pA'. 871 */ 872 if (effective) 873 new->cap_effective = new->cap_permitted; 874 else 875 new->cap_effective = new->cap_ambient; 876 877 if (WARN_ON(!cap_ambient_invariant_ok(new))) 878 return -EPERM; 879 880 if (nonroot_raised_pE(new, old, root_uid, has_fcap)) { 881 ret = audit_log_bprm_fcaps(bprm, new, old); 882 if (ret < 0) 883 return ret; 884 } 885 886 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS); 887 888 if (WARN_ON(!cap_ambient_invariant_ok(new))) 889 return -EPERM; 890 891 /* Check for privilege-elevated exec. */ 892 bprm->cap_elevated = 0; 893 if (is_setid || 894 (!__is_real(root_uid, new) && 895 (effective || 896 __cap_grew(permitted, ambient, new)))) 897 bprm->cap_elevated = 1; 898 899 return 0; 900 } 901 902 /** 903 * cap_inode_setxattr - Determine whether an xattr may be altered 904 * @dentry: The inode/dentry being altered 905 * @name: The name of the xattr to be changed 906 * @value: The value that the xattr will be changed to 907 * @size: The size of value 908 * @flags: The replacement flag 909 * 910 * Determine whether an xattr may be altered or set on an inode, returning 0 if 911 * permission is granted, -ve if denied. 912 * 913 * This is used to make sure security xattrs don't get updated or set by those 914 * who aren't privileged to do so. 915 */ 916 int cap_inode_setxattr(struct dentry *dentry, const char *name, 917 const void *value, size_t size, int flags) 918 { 919 struct user_namespace *user_ns = dentry->d_sb->s_user_ns; 920 921 /* Ignore non-security xattrs */ 922 if (strncmp(name, XATTR_SECURITY_PREFIX, 923 sizeof(XATTR_SECURITY_PREFIX) - 1) != 0) 924 return 0; 925 926 /* 927 * For XATTR_NAME_CAPS the check will be done in 928 * cap_convert_nscap(), called by setxattr() 929 */ 930 if (strcmp(name, XATTR_NAME_CAPS) == 0) 931 return 0; 932 933 if (!ns_capable(user_ns, CAP_SYS_ADMIN)) 934 return -EPERM; 935 return 0; 936 } 937 938 /** 939 * cap_inode_removexattr - Determine whether an xattr may be removed 940 * @dentry: The inode/dentry being altered 941 * @name: The name of the xattr to be changed 942 * 943 * Determine whether an xattr may be removed from an inode, returning 0 if 944 * permission is granted, -ve if denied. 945 * 946 * This is used to make sure security xattrs don't get removed by those who 947 * aren't privileged to remove them. 948 */ 949 int cap_inode_removexattr(struct dentry *dentry, const char *name) 950 { 951 struct user_namespace *user_ns = dentry->d_sb->s_user_ns; 952 953 /* Ignore non-security xattrs */ 954 if (strncmp(name, XATTR_SECURITY_PREFIX, 955 sizeof(XATTR_SECURITY_PREFIX) - 1) != 0) 956 return 0; 957 958 if (strcmp(name, XATTR_NAME_CAPS) == 0) { 959 /* security.capability gets namespaced */ 960 struct inode *inode = d_backing_inode(dentry); 961 if (!inode) 962 return -EINVAL; 963 if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP)) 964 return -EPERM; 965 return 0; 966 } 967 968 if (!ns_capable(user_ns, CAP_SYS_ADMIN)) 969 return -EPERM; 970 return 0; 971 } 972 973 /* 974 * cap_emulate_setxuid() fixes the effective / permitted capabilities of 975 * a process after a call to setuid, setreuid, or setresuid. 976 * 977 * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of 978 * {r,e,s}uid != 0, the permitted and effective capabilities are 979 * cleared. 980 * 981 * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective 982 * capabilities of the process are cleared. 983 * 984 * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective 985 * capabilities are set to the permitted capabilities. 986 * 987 * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should 988 * never happen. 989 * 990 * -astor 991 * 992 * cevans - New behaviour, Oct '99 993 * A process may, via prctl(), elect to keep its capabilities when it 994 * calls setuid() and switches away from uid==0. Both permitted and 995 * effective sets will be retained. 996 * Without this change, it was impossible for a daemon to drop only some 997 * of its privilege. The call to setuid(!=0) would drop all privileges! 998 * Keeping uid 0 is not an option because uid 0 owns too many vital 999 * files.. 1000 * Thanks to Olaf Kirch and Peter Benie for spotting this. 1001 */ 1002 static inline void cap_emulate_setxuid(struct cred *new, const struct cred *old) 1003 { 1004 kuid_t root_uid = make_kuid(old->user_ns, 0); 1005 1006 if ((uid_eq(old->uid, root_uid) || 1007 uid_eq(old->euid, root_uid) || 1008 uid_eq(old->suid, root_uid)) && 1009 (!uid_eq(new->uid, root_uid) && 1010 !uid_eq(new->euid, root_uid) && 1011 !uid_eq(new->suid, root_uid))) { 1012 if (!issecure(SECURE_KEEP_CAPS)) { 1013 cap_clear(new->cap_permitted); 1014 cap_clear(new->cap_effective); 1015 } 1016 1017 /* 1018 * Pre-ambient programs expect setresuid to nonroot followed 1019 * by exec to drop capabilities. We should make sure that 1020 * this remains the case. 1021 */ 1022 cap_clear(new->cap_ambient); 1023 } 1024 if (uid_eq(old->euid, root_uid) && !uid_eq(new->euid, root_uid)) 1025 cap_clear(new->cap_effective); 1026 if (!uid_eq(old->euid, root_uid) && uid_eq(new->euid, root_uid)) 1027 new->cap_effective = new->cap_permitted; 1028 } 1029 1030 /** 1031 * cap_task_fix_setuid - Fix up the results of setuid() call 1032 * @new: The proposed credentials 1033 * @old: The current task's current credentials 1034 * @flags: Indications of what has changed 1035 * 1036 * Fix up the results of setuid() call before the credential changes are 1037 * actually applied, returning 0 to grant the changes, -ve to deny them. 1038 */ 1039 int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags) 1040 { 1041 switch (flags) { 1042 case LSM_SETID_RE: 1043 case LSM_SETID_ID: 1044 case LSM_SETID_RES: 1045 /* juggle the capabilities to follow [RES]UID changes unless 1046 * otherwise suppressed */ 1047 if (!issecure(SECURE_NO_SETUID_FIXUP)) 1048 cap_emulate_setxuid(new, old); 1049 break; 1050 1051 case LSM_SETID_FS: 1052 /* juggle the capabilties to follow FSUID changes, unless 1053 * otherwise suppressed 1054 * 1055 * FIXME - is fsuser used for all CAP_FS_MASK capabilities? 1056 * if not, we might be a bit too harsh here. 1057 */ 1058 if (!issecure(SECURE_NO_SETUID_FIXUP)) { 1059 kuid_t root_uid = make_kuid(old->user_ns, 0); 1060 if (uid_eq(old->fsuid, root_uid) && !uid_eq(new->fsuid, root_uid)) 1061 new->cap_effective = 1062 cap_drop_fs_set(new->cap_effective); 1063 1064 if (!uid_eq(old->fsuid, root_uid) && uid_eq(new->fsuid, root_uid)) 1065 new->cap_effective = 1066 cap_raise_fs_set(new->cap_effective, 1067 new->cap_permitted); 1068 } 1069 break; 1070 1071 default: 1072 return -EINVAL; 1073 } 1074 1075 return 0; 1076 } 1077 1078 /* 1079 * Rationale: code calling task_setscheduler, task_setioprio, and 1080 * task_setnice, assumes that 1081 * . if capable(cap_sys_nice), then those actions should be allowed 1082 * . if not capable(cap_sys_nice), but acting on your own processes, 1083 * then those actions should be allowed 1084 * This is insufficient now since you can call code without suid, but 1085 * yet with increased caps. 1086 * So we check for increased caps on the target process. 1087 */ 1088 static int cap_safe_nice(struct task_struct *p) 1089 { 1090 int is_subset, ret = 0; 1091 1092 rcu_read_lock(); 1093 is_subset = cap_issubset(__task_cred(p)->cap_permitted, 1094 current_cred()->cap_permitted); 1095 if (!is_subset && !ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) 1096 ret = -EPERM; 1097 rcu_read_unlock(); 1098 1099 return ret; 1100 } 1101 1102 /** 1103 * cap_task_setscheduler - Detemine if scheduler policy change is permitted 1104 * @p: The task to affect 1105 * 1106 * Detemine if the requested scheduler policy change is permitted for the 1107 * specified task, returning 0 if permission is granted, -ve if denied. 1108 */ 1109 int cap_task_setscheduler(struct task_struct *p) 1110 { 1111 return cap_safe_nice(p); 1112 } 1113 1114 /** 1115 * cap_task_ioprio - Detemine if I/O priority change is permitted 1116 * @p: The task to affect 1117 * @ioprio: The I/O priority to set 1118 * 1119 * Detemine if the requested I/O priority change is permitted for the specified 1120 * task, returning 0 if permission is granted, -ve if denied. 1121 */ 1122 int cap_task_setioprio(struct task_struct *p, int ioprio) 1123 { 1124 return cap_safe_nice(p); 1125 } 1126 1127 /** 1128 * cap_task_ioprio - Detemine if task priority change is permitted 1129 * @p: The task to affect 1130 * @nice: The nice value to set 1131 * 1132 * Detemine if the requested task priority change is permitted for the 1133 * specified task, returning 0 if permission is granted, -ve if denied. 1134 */ 1135 int cap_task_setnice(struct task_struct *p, int nice) 1136 { 1137 return cap_safe_nice(p); 1138 } 1139 1140 /* 1141 * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from 1142 * the current task's bounding set. Returns 0 on success, -ve on error. 1143 */ 1144 static int cap_prctl_drop(unsigned long cap) 1145 { 1146 struct cred *new; 1147 1148 if (!ns_capable(current_user_ns(), CAP_SETPCAP)) 1149 return -EPERM; 1150 if (!cap_valid(cap)) 1151 return -EINVAL; 1152 1153 new = prepare_creds(); 1154 if (!new) 1155 return -ENOMEM; 1156 cap_lower(new->cap_bset, cap); 1157 return commit_creds(new); 1158 } 1159 1160 /** 1161 * cap_task_prctl - Implement process control functions for this security module 1162 * @option: The process control function requested 1163 * @arg2, @arg3, @arg4, @arg5: The argument data for this function 1164 * 1165 * Allow process control functions (sys_prctl()) to alter capabilities; may 1166 * also deny access to other functions not otherwise implemented here. 1167 * 1168 * Returns 0 or +ve on success, -ENOSYS if this function is not implemented 1169 * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM 1170 * modules will consider performing the function. 1171 */ 1172 int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, 1173 unsigned long arg4, unsigned long arg5) 1174 { 1175 const struct cred *old = current_cred(); 1176 struct cred *new; 1177 1178 switch (option) { 1179 case PR_CAPBSET_READ: 1180 if (!cap_valid(arg2)) 1181 return -EINVAL; 1182 return !!cap_raised(old->cap_bset, arg2); 1183 1184 case PR_CAPBSET_DROP: 1185 return cap_prctl_drop(arg2); 1186 1187 /* 1188 * The next four prctl's remain to assist with transitioning a 1189 * system from legacy UID=0 based privilege (when filesystem 1190 * capabilities are not in use) to a system using filesystem 1191 * capabilities only - as the POSIX.1e draft intended. 1192 * 1193 * Note: 1194 * 1195 * PR_SET_SECUREBITS = 1196 * issecure_mask(SECURE_KEEP_CAPS_LOCKED) 1197 * | issecure_mask(SECURE_NOROOT) 1198 * | issecure_mask(SECURE_NOROOT_LOCKED) 1199 * | issecure_mask(SECURE_NO_SETUID_FIXUP) 1200 * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED) 1201 * 1202 * will ensure that the current process and all of its 1203 * children will be locked into a pure 1204 * capability-based-privilege environment. 1205 */ 1206 case PR_SET_SECUREBITS: 1207 if ((((old->securebits & SECURE_ALL_LOCKS) >> 1) 1208 & (old->securebits ^ arg2)) /*[1]*/ 1209 || ((old->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/ 1210 || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/ 1211 || (cap_capable(current_cred(), 1212 current_cred()->user_ns, 1213 CAP_SETPCAP, 1214 CAP_OPT_NONE) != 0) /*[4]*/ 1215 /* 1216 * [1] no changing of bits that are locked 1217 * [2] no unlocking of locks 1218 * [3] no setting of unsupported bits 1219 * [4] doing anything requires privilege (go read about 1220 * the "sendmail capabilities bug") 1221 */ 1222 ) 1223 /* cannot change a locked bit */ 1224 return -EPERM; 1225 1226 new = prepare_creds(); 1227 if (!new) 1228 return -ENOMEM; 1229 new->securebits = arg2; 1230 return commit_creds(new); 1231 1232 case PR_GET_SECUREBITS: 1233 return old->securebits; 1234 1235 case PR_GET_KEEPCAPS: 1236 return !!issecure(SECURE_KEEP_CAPS); 1237 1238 case PR_SET_KEEPCAPS: 1239 if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */ 1240 return -EINVAL; 1241 if (issecure(SECURE_KEEP_CAPS_LOCKED)) 1242 return -EPERM; 1243 1244 new = prepare_creds(); 1245 if (!new) 1246 return -ENOMEM; 1247 if (arg2) 1248 new->securebits |= issecure_mask(SECURE_KEEP_CAPS); 1249 else 1250 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS); 1251 return commit_creds(new); 1252 1253 case PR_CAP_AMBIENT: 1254 if (arg2 == PR_CAP_AMBIENT_CLEAR_ALL) { 1255 if (arg3 | arg4 | arg5) 1256 return -EINVAL; 1257 1258 new = prepare_creds(); 1259 if (!new) 1260 return -ENOMEM; 1261 cap_clear(new->cap_ambient); 1262 return commit_creds(new); 1263 } 1264 1265 if (((!cap_valid(arg3)) | arg4 | arg5)) 1266 return -EINVAL; 1267 1268 if (arg2 == PR_CAP_AMBIENT_IS_SET) { 1269 return !!cap_raised(current_cred()->cap_ambient, arg3); 1270 } else if (arg2 != PR_CAP_AMBIENT_RAISE && 1271 arg2 != PR_CAP_AMBIENT_LOWER) { 1272 return -EINVAL; 1273 } else { 1274 if (arg2 == PR_CAP_AMBIENT_RAISE && 1275 (!cap_raised(current_cred()->cap_permitted, arg3) || 1276 !cap_raised(current_cred()->cap_inheritable, 1277 arg3) || 1278 issecure(SECURE_NO_CAP_AMBIENT_RAISE))) 1279 return -EPERM; 1280 1281 new = prepare_creds(); 1282 if (!new) 1283 return -ENOMEM; 1284 if (arg2 == PR_CAP_AMBIENT_RAISE) 1285 cap_raise(new->cap_ambient, arg3); 1286 else 1287 cap_lower(new->cap_ambient, arg3); 1288 return commit_creds(new); 1289 } 1290 1291 default: 1292 /* No functionality available - continue with default */ 1293 return -ENOSYS; 1294 } 1295 } 1296 1297 /** 1298 * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted 1299 * @mm: The VM space in which the new mapping is to be made 1300 * @pages: The size of the mapping 1301 * 1302 * Determine whether the allocation of a new virtual mapping by the current 1303 * task is permitted, returning 1 if permission is granted, 0 if not. 1304 */ 1305 int cap_vm_enough_memory(struct mm_struct *mm, long pages) 1306 { 1307 int cap_sys_admin = 0; 1308 1309 if (cap_capable(current_cred(), &init_user_ns, 1310 CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) == 0) 1311 cap_sys_admin = 1; 1312 1313 return cap_sys_admin; 1314 } 1315 1316 /* 1317 * cap_mmap_addr - check if able to map given addr 1318 * @addr: address attempting to be mapped 1319 * 1320 * If the process is attempting to map memory below dac_mmap_min_addr they need 1321 * CAP_SYS_RAWIO. The other parameters to this function are unused by the 1322 * capability security module. Returns 0 if this mapping should be allowed 1323 * -EPERM if not. 1324 */ 1325 int cap_mmap_addr(unsigned long addr) 1326 { 1327 int ret = 0; 1328 1329 if (addr < dac_mmap_min_addr) { 1330 ret = cap_capable(current_cred(), &init_user_ns, CAP_SYS_RAWIO, 1331 CAP_OPT_NONE); 1332 /* set PF_SUPERPRIV if it turns out we allow the low mmap */ 1333 if (ret == 0) 1334 current->flags |= PF_SUPERPRIV; 1335 } 1336 return ret; 1337 } 1338 1339 int cap_mmap_file(struct file *file, unsigned long reqprot, 1340 unsigned long prot, unsigned long flags) 1341 { 1342 return 0; 1343 } 1344 1345 #ifdef CONFIG_SECURITY 1346 1347 struct security_hook_list capability_hooks[] __lsm_ro_after_init = { 1348 LSM_HOOK_INIT(capable, cap_capable), 1349 LSM_HOOK_INIT(settime, cap_settime), 1350 LSM_HOOK_INIT(ptrace_access_check, cap_ptrace_access_check), 1351 LSM_HOOK_INIT(ptrace_traceme, cap_ptrace_traceme), 1352 LSM_HOOK_INIT(capget, cap_capget), 1353 LSM_HOOK_INIT(capset, cap_capset), 1354 LSM_HOOK_INIT(bprm_set_creds, cap_bprm_set_creds), 1355 LSM_HOOK_INIT(inode_need_killpriv, cap_inode_need_killpriv), 1356 LSM_HOOK_INIT(inode_killpriv, cap_inode_killpriv), 1357 LSM_HOOK_INIT(inode_getsecurity, cap_inode_getsecurity), 1358 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr), 1359 LSM_HOOK_INIT(mmap_file, cap_mmap_file), 1360 LSM_HOOK_INIT(task_fix_setuid, cap_task_fix_setuid), 1361 LSM_HOOK_INIT(task_prctl, cap_task_prctl), 1362 LSM_HOOK_INIT(task_setscheduler, cap_task_setscheduler), 1363 LSM_HOOK_INIT(task_setioprio, cap_task_setioprio), 1364 LSM_HOOK_INIT(task_setnice, cap_task_setnice), 1365 LSM_HOOK_INIT(vm_enough_memory, cap_vm_enough_memory), 1366 }; 1367 1368 static int __init capability_init(void) 1369 { 1370 security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks), 1371 "capability"); 1372 return 0; 1373 } 1374 1375 DEFINE_LSM(capability) = { 1376 .name = "capability", 1377 .order = LSM_ORDER_FIRST, 1378 .init = capability_init, 1379 }; 1380 1381 #endif /* CONFIG_SECURITY */ 1382