1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* Common capabilities, needed by capability.o. 3 */ 4 5 #include <linux/capability.h> 6 #include <linux/audit.h> 7 #include <linux/init.h> 8 #include <linux/kernel.h> 9 #include <linux/lsm_hooks.h> 10 #include <linux/file.h> 11 #include <linux/mm.h> 12 #include <linux/mman.h> 13 #include <linux/pagemap.h> 14 #include <linux/swap.h> 15 #include <linux/skbuff.h> 16 #include <linux/netlink.h> 17 #include <linux/ptrace.h> 18 #include <linux/xattr.h> 19 #include <linux/hugetlb.h> 20 #include <linux/mount.h> 21 #include <linux/sched.h> 22 #include <linux/prctl.h> 23 #include <linux/securebits.h> 24 #include <linux/user_namespace.h> 25 #include <linux/binfmts.h> 26 #include <linux/personality.h> 27 28 /* 29 * If a non-root user executes a setuid-root binary in 30 * !secure(SECURE_NOROOT) mode, then we raise capabilities. 31 * However if fE is also set, then the intent is for only 32 * the file capabilities to be applied, and the setuid-root 33 * bit is left on either to change the uid (plausible) or 34 * to get full privilege on a kernel without file capabilities 35 * support. So in that case we do not raise capabilities. 36 * 37 * Warn if that happens, once per boot. 38 */ 39 static void warn_setuid_and_fcaps_mixed(const char *fname) 40 { 41 static int warned; 42 if (!warned) { 43 printk(KERN_INFO "warning: `%s' has both setuid-root and" 44 " effective capabilities. Therefore not raising all" 45 " capabilities.\n", fname); 46 warned = 1; 47 } 48 } 49 50 /** 51 * cap_capable - Determine whether a task has a particular effective capability 52 * @cred: The credentials to use 53 * @ns: The user namespace in which we need the capability 54 * @cap: The capability to check for 55 * @opts: Bitmask of options defined in include/linux/security.h 56 * 57 * Determine whether the nominated task has the specified capability amongst 58 * its effective set, returning 0 if it does, -ve if it does not. 59 * 60 * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable() 61 * and has_capability() functions. That is, it has the reverse semantics: 62 * cap_has_capability() returns 0 when a task has a capability, but the 63 * kernel's capable() and has_capability() returns 1 for this case. 64 */ 65 int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, 66 int cap, unsigned int opts) 67 { 68 struct user_namespace *ns = targ_ns; 69 70 /* See if cred has the capability in the target user namespace 71 * by examining the target user namespace and all of the target 72 * user namespace's parents. 73 */ 74 for (;;) { 75 /* Do we have the necessary capabilities? */ 76 if (ns == cred->user_ns) 77 return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; 78 79 /* 80 * If we're already at a lower level than we're looking for, 81 * we're done searching. 82 */ 83 if (ns->level <= cred->user_ns->level) 84 return -EPERM; 85 86 /* 87 * The owner of the user namespace in the parent of the 88 * user namespace has all caps. 89 */ 90 if ((ns->parent == cred->user_ns) && uid_eq(ns->owner, cred->euid)) 91 return 0; 92 93 /* 94 * If you have a capability in a parent user ns, then you have 95 * it over all children user namespaces as well. 96 */ 97 ns = ns->parent; 98 } 99 100 /* We never get here */ 101 } 102 103 /** 104 * cap_settime - Determine whether the current process may set the system clock 105 * @ts: The time to set 106 * @tz: The timezone to set 107 * 108 * Determine whether the current process may set the system clock and timezone 109 * information, returning 0 if permission granted, -ve if denied. 110 */ 111 int cap_settime(const struct timespec64 *ts, const struct timezone *tz) 112 { 113 if (!capable(CAP_SYS_TIME)) 114 return -EPERM; 115 return 0; 116 } 117 118 /** 119 * cap_ptrace_access_check - Determine whether the current process may access 120 * another 121 * @child: The process to be accessed 122 * @mode: The mode of attachment. 123 * 124 * If we are in the same or an ancestor user_ns and have all the target 125 * task's capabilities, then ptrace access is allowed. 126 * If we have the ptrace capability to the target user_ns, then ptrace 127 * access is allowed. 128 * Else denied. 129 * 130 * Determine whether a process may access another, returning 0 if permission 131 * granted, -ve if denied. 132 */ 133 int cap_ptrace_access_check(struct task_struct *child, unsigned int mode) 134 { 135 int ret = 0; 136 const struct cred *cred, *child_cred; 137 const kernel_cap_t *caller_caps; 138 139 rcu_read_lock(); 140 cred = current_cred(); 141 child_cred = __task_cred(child); 142 if (mode & PTRACE_MODE_FSCREDS) 143 caller_caps = &cred->cap_effective; 144 else 145 caller_caps = &cred->cap_permitted; 146 if (cred->user_ns == child_cred->user_ns && 147 cap_issubset(child_cred->cap_permitted, *caller_caps)) 148 goto out; 149 if (ns_capable(child_cred->user_ns, CAP_SYS_PTRACE)) 150 goto out; 151 ret = -EPERM; 152 out: 153 rcu_read_unlock(); 154 return ret; 155 } 156 157 /** 158 * cap_ptrace_traceme - Determine whether another process may trace the current 159 * @parent: The task proposed to be the tracer 160 * 161 * If parent is in the same or an ancestor user_ns and has all current's 162 * capabilities, then ptrace access is allowed. 163 * If parent has the ptrace capability to current's user_ns, then ptrace 164 * access is allowed. 165 * Else denied. 166 * 167 * Determine whether the nominated task is permitted to trace the current 168 * process, returning 0 if permission is granted, -ve if denied. 169 */ 170 int cap_ptrace_traceme(struct task_struct *parent) 171 { 172 int ret = 0; 173 const struct cred *cred, *child_cred; 174 175 rcu_read_lock(); 176 cred = __task_cred(parent); 177 child_cred = current_cred(); 178 if (cred->user_ns == child_cred->user_ns && 179 cap_issubset(child_cred->cap_permitted, cred->cap_permitted)) 180 goto out; 181 if (has_ns_capability(parent, child_cred->user_ns, CAP_SYS_PTRACE)) 182 goto out; 183 ret = -EPERM; 184 out: 185 rcu_read_unlock(); 186 return ret; 187 } 188 189 /** 190 * cap_capget - Retrieve a task's capability sets 191 * @target: The task from which to retrieve the capability sets 192 * @effective: The place to record the effective set 193 * @inheritable: The place to record the inheritable set 194 * @permitted: The place to record the permitted set 195 * 196 * This function retrieves the capabilities of the nominated task and returns 197 * them to the caller. 198 */ 199 int cap_capget(struct task_struct *target, kernel_cap_t *effective, 200 kernel_cap_t *inheritable, kernel_cap_t *permitted) 201 { 202 const struct cred *cred; 203 204 /* Derived from kernel/capability.c:sys_capget. */ 205 rcu_read_lock(); 206 cred = __task_cred(target); 207 *effective = cred->cap_effective; 208 *inheritable = cred->cap_inheritable; 209 *permitted = cred->cap_permitted; 210 rcu_read_unlock(); 211 return 0; 212 } 213 214 /* 215 * Determine whether the inheritable capabilities are limited to the old 216 * permitted set. Returns 1 if they are limited, 0 if they are not. 217 */ 218 static inline int cap_inh_is_capped(void) 219 { 220 /* they are so limited unless the current task has the CAP_SETPCAP 221 * capability 222 */ 223 if (cap_capable(current_cred(), current_cred()->user_ns, 224 CAP_SETPCAP, CAP_OPT_NONE) == 0) 225 return 0; 226 return 1; 227 } 228 229 /** 230 * cap_capset - Validate and apply proposed changes to current's capabilities 231 * @new: The proposed new credentials; alterations should be made here 232 * @old: The current task's current credentials 233 * @effective: A pointer to the proposed new effective capabilities set 234 * @inheritable: A pointer to the proposed new inheritable capabilities set 235 * @permitted: A pointer to the proposed new permitted capabilities set 236 * 237 * This function validates and applies a proposed mass change to the current 238 * process's capability sets. The changes are made to the proposed new 239 * credentials, and assuming no error, will be committed by the caller of LSM. 240 */ 241 int cap_capset(struct cred *new, 242 const struct cred *old, 243 const kernel_cap_t *effective, 244 const kernel_cap_t *inheritable, 245 const kernel_cap_t *permitted) 246 { 247 if (cap_inh_is_capped() && 248 !cap_issubset(*inheritable, 249 cap_combine(old->cap_inheritable, 250 old->cap_permitted))) 251 /* incapable of using this inheritable set */ 252 return -EPERM; 253 254 if (!cap_issubset(*inheritable, 255 cap_combine(old->cap_inheritable, 256 old->cap_bset))) 257 /* no new pI capabilities outside bounding set */ 258 return -EPERM; 259 260 /* verify restrictions on target's new Permitted set */ 261 if (!cap_issubset(*permitted, old->cap_permitted)) 262 return -EPERM; 263 264 /* verify the _new_Effective_ is a subset of the _new_Permitted_ */ 265 if (!cap_issubset(*effective, *permitted)) 266 return -EPERM; 267 268 new->cap_effective = *effective; 269 new->cap_inheritable = *inheritable; 270 new->cap_permitted = *permitted; 271 272 /* 273 * Mask off ambient bits that are no longer both permitted and 274 * inheritable. 275 */ 276 new->cap_ambient = cap_intersect(new->cap_ambient, 277 cap_intersect(*permitted, 278 *inheritable)); 279 if (WARN_ON(!cap_ambient_invariant_ok(new))) 280 return -EINVAL; 281 return 0; 282 } 283 284 /** 285 * cap_inode_need_killpriv - Determine if inode change affects privileges 286 * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV 287 * 288 * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV 289 * affects the security markings on that inode, and if it is, should 290 * inode_killpriv() be invoked or the change rejected. 291 * 292 * Returns 1 if security.capability has a value, meaning inode_killpriv() 293 * is required, 0 otherwise, meaning inode_killpriv() is not required. 294 */ 295 int cap_inode_need_killpriv(struct dentry *dentry) 296 { 297 struct inode *inode = d_backing_inode(dentry); 298 int error; 299 300 error = __vfs_getxattr(dentry, inode, XATTR_NAME_CAPS, NULL, 0); 301 return error > 0; 302 } 303 304 /** 305 * cap_inode_killpriv - Erase the security markings on an inode 306 * @dentry: The inode/dentry to alter 307 * 308 * Erase the privilege-enhancing security markings on an inode. 309 * 310 * Returns 0 if successful, -ve on error. 311 */ 312 int cap_inode_killpriv(struct dentry *dentry) 313 { 314 int error; 315 316 error = __vfs_removexattr(dentry, XATTR_NAME_CAPS); 317 if (error == -EOPNOTSUPP) 318 error = 0; 319 return error; 320 } 321 322 static bool rootid_owns_currentns(kuid_t kroot) 323 { 324 struct user_namespace *ns; 325 326 if (!uid_valid(kroot)) 327 return false; 328 329 for (ns = current_user_ns(); ; ns = ns->parent) { 330 if (from_kuid(ns, kroot) == 0) 331 return true; 332 if (ns == &init_user_ns) 333 break; 334 } 335 336 return false; 337 } 338 339 static __u32 sansflags(__u32 m) 340 { 341 return m & ~VFS_CAP_FLAGS_EFFECTIVE; 342 } 343 344 static bool is_v2header(size_t size, const struct vfs_cap_data *cap) 345 { 346 if (size != XATTR_CAPS_SZ_2) 347 return false; 348 return sansflags(le32_to_cpu(cap->magic_etc)) == VFS_CAP_REVISION_2; 349 } 350 351 static bool is_v3header(size_t size, const struct vfs_cap_data *cap) 352 { 353 if (size != XATTR_CAPS_SZ_3) 354 return false; 355 return sansflags(le32_to_cpu(cap->magic_etc)) == VFS_CAP_REVISION_3; 356 } 357 358 /* 359 * getsecurity: We are called for security.* before any attempt to read the 360 * xattr from the inode itself. 361 * 362 * This gives us a chance to read the on-disk value and convert it. If we 363 * return -EOPNOTSUPP, then vfs_getxattr() will call the i_op handler. 364 * 365 * Note we are not called by vfs_getxattr_alloc(), but that is only called 366 * by the integrity subsystem, which really wants the unconverted values - 367 * so that's good. 368 */ 369 int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer, 370 bool alloc) 371 { 372 int size, ret; 373 kuid_t kroot; 374 uid_t root, mappedroot; 375 char *tmpbuf = NULL; 376 struct vfs_cap_data *cap; 377 struct vfs_ns_cap_data *nscap; 378 struct dentry *dentry; 379 struct user_namespace *fs_ns; 380 381 if (strcmp(name, "capability") != 0) 382 return -EOPNOTSUPP; 383 384 dentry = d_find_any_alias(inode); 385 if (!dentry) 386 return -EINVAL; 387 388 size = sizeof(struct vfs_ns_cap_data); 389 ret = (int) vfs_getxattr_alloc(dentry, XATTR_NAME_CAPS, 390 &tmpbuf, size, GFP_NOFS); 391 dput(dentry); 392 393 if (ret < 0) 394 return ret; 395 396 fs_ns = inode->i_sb->s_user_ns; 397 cap = (struct vfs_cap_data *) tmpbuf; 398 if (is_v2header((size_t) ret, cap)) { 399 /* If this is sizeof(vfs_cap_data) then we're ok with the 400 * on-disk value, so return that. */ 401 if (alloc) 402 *buffer = tmpbuf; 403 else 404 kfree(tmpbuf); 405 return ret; 406 } else if (!is_v3header((size_t) ret, cap)) { 407 kfree(tmpbuf); 408 return -EINVAL; 409 } 410 411 nscap = (struct vfs_ns_cap_data *) tmpbuf; 412 root = le32_to_cpu(nscap->rootid); 413 kroot = make_kuid(fs_ns, root); 414 415 /* If the root kuid maps to a valid uid in current ns, then return 416 * this as a nscap. */ 417 mappedroot = from_kuid(current_user_ns(), kroot); 418 if (mappedroot != (uid_t)-1 && mappedroot != (uid_t)0) { 419 if (alloc) { 420 *buffer = tmpbuf; 421 nscap->rootid = cpu_to_le32(mappedroot); 422 } else 423 kfree(tmpbuf); 424 return size; 425 } 426 427 if (!rootid_owns_currentns(kroot)) { 428 kfree(tmpbuf); 429 return -EOPNOTSUPP; 430 } 431 432 /* This comes from a parent namespace. Return as a v2 capability */ 433 size = sizeof(struct vfs_cap_data); 434 if (alloc) { 435 *buffer = kmalloc(size, GFP_ATOMIC); 436 if (*buffer) { 437 struct vfs_cap_data *cap = *buffer; 438 __le32 nsmagic, magic; 439 magic = VFS_CAP_REVISION_2; 440 nsmagic = le32_to_cpu(nscap->magic_etc); 441 if (nsmagic & VFS_CAP_FLAGS_EFFECTIVE) 442 magic |= VFS_CAP_FLAGS_EFFECTIVE; 443 memcpy(&cap->data, &nscap->data, sizeof(__le32) * 2 * VFS_CAP_U32); 444 cap->magic_etc = cpu_to_le32(magic); 445 } else { 446 size = -ENOMEM; 447 } 448 } 449 kfree(tmpbuf); 450 return size; 451 } 452 453 static kuid_t rootid_from_xattr(const void *value, size_t size, 454 struct user_namespace *task_ns) 455 { 456 const struct vfs_ns_cap_data *nscap = value; 457 uid_t rootid = 0; 458 459 if (size == XATTR_CAPS_SZ_3) 460 rootid = le32_to_cpu(nscap->rootid); 461 462 return make_kuid(task_ns, rootid); 463 } 464 465 static bool validheader(size_t size, const struct vfs_cap_data *cap) 466 { 467 return is_v2header(size, cap) || is_v3header(size, cap); 468 } 469 470 /* 471 * User requested a write of security.capability. If needed, update the 472 * xattr to change from v2 to v3, or to fixup the v3 rootid. 473 * 474 * If all is ok, we return the new size, on error return < 0. 475 */ 476 int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size) 477 { 478 struct vfs_ns_cap_data *nscap; 479 uid_t nsrootid; 480 const struct vfs_cap_data *cap = *ivalue; 481 __u32 magic, nsmagic; 482 struct inode *inode = d_backing_inode(dentry); 483 struct user_namespace *task_ns = current_user_ns(), 484 *fs_ns = inode->i_sb->s_user_ns; 485 kuid_t rootid; 486 size_t newsize; 487 488 if (!*ivalue) 489 return -EINVAL; 490 if (!validheader(size, cap)) 491 return -EINVAL; 492 if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP)) 493 return -EPERM; 494 if (size == XATTR_CAPS_SZ_2) 495 if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP)) 496 /* user is privileged, just write the v2 */ 497 return size; 498 499 rootid = rootid_from_xattr(*ivalue, size, task_ns); 500 if (!uid_valid(rootid)) 501 return -EINVAL; 502 503 nsrootid = from_kuid(fs_ns, rootid); 504 if (nsrootid == -1) 505 return -EINVAL; 506 507 newsize = sizeof(struct vfs_ns_cap_data); 508 nscap = kmalloc(newsize, GFP_ATOMIC); 509 if (!nscap) 510 return -ENOMEM; 511 nscap->rootid = cpu_to_le32(nsrootid); 512 nsmagic = VFS_CAP_REVISION_3; 513 magic = le32_to_cpu(cap->magic_etc); 514 if (magic & VFS_CAP_FLAGS_EFFECTIVE) 515 nsmagic |= VFS_CAP_FLAGS_EFFECTIVE; 516 nscap->magic_etc = cpu_to_le32(nsmagic); 517 memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32); 518 519 kvfree(*ivalue); 520 *ivalue = nscap; 521 return newsize; 522 } 523 524 /* 525 * Calculate the new process capability sets from the capability sets attached 526 * to a file. 527 */ 528 static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps, 529 struct linux_binprm *bprm, 530 bool *effective, 531 bool *has_fcap) 532 { 533 struct cred *new = bprm->cred; 534 unsigned i; 535 int ret = 0; 536 537 if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE) 538 *effective = true; 539 540 if (caps->magic_etc & VFS_CAP_REVISION_MASK) 541 *has_fcap = true; 542 543 CAP_FOR_EACH_U32(i) { 544 __u32 permitted = caps->permitted.cap[i]; 545 __u32 inheritable = caps->inheritable.cap[i]; 546 547 /* 548 * pP' = (X & fP) | (pI & fI) 549 * The addition of pA' is handled later. 550 */ 551 new->cap_permitted.cap[i] = 552 (new->cap_bset.cap[i] & permitted) | 553 (new->cap_inheritable.cap[i] & inheritable); 554 555 if (permitted & ~new->cap_permitted.cap[i]) 556 /* insufficient to execute correctly */ 557 ret = -EPERM; 558 } 559 560 /* 561 * For legacy apps, with no internal support for recognizing they 562 * do not have enough capabilities, we return an error if they are 563 * missing some "forced" (aka file-permitted) capabilities. 564 */ 565 return *effective ? ret : 0; 566 } 567 568 /* 569 * Extract the on-exec-apply capability sets for an executable file. 570 */ 571 int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps) 572 { 573 struct inode *inode = d_backing_inode(dentry); 574 __u32 magic_etc; 575 unsigned tocopy, i; 576 int size; 577 struct vfs_ns_cap_data data, *nscaps = &data; 578 struct vfs_cap_data *caps = (struct vfs_cap_data *) &data; 579 kuid_t rootkuid; 580 struct user_namespace *fs_ns; 581 582 memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data)); 583 584 if (!inode) 585 return -ENODATA; 586 587 fs_ns = inode->i_sb->s_user_ns; 588 size = __vfs_getxattr((struct dentry *)dentry, inode, 589 XATTR_NAME_CAPS, &data, XATTR_CAPS_SZ); 590 if (size == -ENODATA || size == -EOPNOTSUPP) 591 /* no data, that's ok */ 592 return -ENODATA; 593 594 if (size < 0) 595 return size; 596 597 if (size < sizeof(magic_etc)) 598 return -EINVAL; 599 600 cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps->magic_etc); 601 602 rootkuid = make_kuid(fs_ns, 0); 603 switch (magic_etc & VFS_CAP_REVISION_MASK) { 604 case VFS_CAP_REVISION_1: 605 if (size != XATTR_CAPS_SZ_1) 606 return -EINVAL; 607 tocopy = VFS_CAP_U32_1; 608 break; 609 case VFS_CAP_REVISION_2: 610 if (size != XATTR_CAPS_SZ_2) 611 return -EINVAL; 612 tocopy = VFS_CAP_U32_2; 613 break; 614 case VFS_CAP_REVISION_3: 615 if (size != XATTR_CAPS_SZ_3) 616 return -EINVAL; 617 tocopy = VFS_CAP_U32_3; 618 rootkuid = make_kuid(fs_ns, le32_to_cpu(nscaps->rootid)); 619 break; 620 621 default: 622 return -EINVAL; 623 } 624 /* Limit the caps to the mounter of the filesystem 625 * or the more limited uid specified in the xattr. 626 */ 627 if (!rootid_owns_currentns(rootkuid)) 628 return -ENODATA; 629 630 CAP_FOR_EACH_U32(i) { 631 if (i >= tocopy) 632 break; 633 cpu_caps->permitted.cap[i] = le32_to_cpu(caps->data[i].permitted); 634 cpu_caps->inheritable.cap[i] = le32_to_cpu(caps->data[i].inheritable); 635 } 636 637 cpu_caps->permitted.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK; 638 cpu_caps->inheritable.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK; 639 640 cpu_caps->rootid = rootkuid; 641 642 return 0; 643 } 644 645 /* 646 * Attempt to get the on-exec apply capability sets for an executable file from 647 * its xattrs and, if present, apply them to the proposed credentials being 648 * constructed by execve(). 649 */ 650 static int get_file_caps(struct linux_binprm *bprm, struct file *file, 651 bool *effective, bool *has_fcap) 652 { 653 int rc = 0; 654 struct cpu_vfs_cap_data vcaps; 655 656 cap_clear(bprm->cred->cap_permitted); 657 658 if (!file_caps_enabled) 659 return 0; 660 661 if (!mnt_may_suid(file->f_path.mnt)) 662 return 0; 663 664 /* 665 * This check is redundant with mnt_may_suid() but is kept to make 666 * explicit that capability bits are limited to s_user_ns and its 667 * descendants. 668 */ 669 if (!current_in_userns(file->f_path.mnt->mnt_sb->s_user_ns)) 670 return 0; 671 672 rc = get_vfs_caps_from_disk(file->f_path.dentry, &vcaps); 673 if (rc < 0) { 674 if (rc == -EINVAL) 675 printk(KERN_NOTICE "Invalid argument reading file caps for %s\n", 676 bprm->filename); 677 else if (rc == -ENODATA) 678 rc = 0; 679 goto out; 680 } 681 682 rc = bprm_caps_from_vfs_caps(&vcaps, bprm, effective, has_fcap); 683 684 out: 685 if (rc) 686 cap_clear(bprm->cred->cap_permitted); 687 688 return rc; 689 } 690 691 static inline bool root_privileged(void) { return !issecure(SECURE_NOROOT); } 692 693 static inline bool __is_real(kuid_t uid, struct cred *cred) 694 { return uid_eq(cred->uid, uid); } 695 696 static inline bool __is_eff(kuid_t uid, struct cred *cred) 697 { return uid_eq(cred->euid, uid); } 698 699 static inline bool __is_suid(kuid_t uid, struct cred *cred) 700 { return !__is_real(uid, cred) && __is_eff(uid, cred); } 701 702 /* 703 * handle_privileged_root - Handle case of privileged root 704 * @bprm: The execution parameters, including the proposed creds 705 * @has_fcap: Are any file capabilities set? 706 * @effective: Do we have effective root privilege? 707 * @root_uid: This namespace' root UID WRT initial USER namespace 708 * 709 * Handle the case where root is privileged and hasn't been neutered by 710 * SECURE_NOROOT. If file capabilities are set, they won't be combined with 711 * set UID root and nothing is changed. If we are root, cap_permitted is 712 * updated. If we have become set UID root, the effective bit is set. 713 */ 714 static void handle_privileged_root(struct linux_binprm *bprm, bool has_fcap, 715 bool *effective, kuid_t root_uid) 716 { 717 const struct cred *old = current_cred(); 718 struct cred *new = bprm->cred; 719 720 if (!root_privileged()) 721 return; 722 /* 723 * If the legacy file capability is set, then don't set privs 724 * for a setuid root binary run by a non-root user. Do set it 725 * for a root user just to cause least surprise to an admin. 726 */ 727 if (has_fcap && __is_suid(root_uid, new)) { 728 warn_setuid_and_fcaps_mixed(bprm->filename); 729 return; 730 } 731 /* 732 * To support inheritance of root-permissions and suid-root 733 * executables under compatibility mode, we override the 734 * capability sets for the file. 735 */ 736 if (__is_eff(root_uid, new) || __is_real(root_uid, new)) { 737 /* pP' = (cap_bset & ~0) | (pI & ~0) */ 738 new->cap_permitted = cap_combine(old->cap_bset, 739 old->cap_inheritable); 740 } 741 /* 742 * If only the real uid is 0, we do not set the effective bit. 743 */ 744 if (__is_eff(root_uid, new)) 745 *effective = true; 746 } 747 748 #define __cap_gained(field, target, source) \ 749 !cap_issubset(target->cap_##field, source->cap_##field) 750 #define __cap_grew(target, source, cred) \ 751 !cap_issubset(cred->cap_##target, cred->cap_##source) 752 #define __cap_full(field, cred) \ 753 cap_issubset(CAP_FULL_SET, cred->cap_##field) 754 755 static inline bool __is_setuid(struct cred *new, const struct cred *old) 756 { return !uid_eq(new->euid, old->uid); } 757 758 static inline bool __is_setgid(struct cred *new, const struct cred *old) 759 { return !gid_eq(new->egid, old->gid); } 760 761 /* 762 * 1) Audit candidate if current->cap_effective is set 763 * 764 * We do not bother to audit if 3 things are true: 765 * 1) cap_effective has all caps 766 * 2) we became root *OR* are were already root 767 * 3) root is supposed to have all caps (SECURE_NOROOT) 768 * Since this is just a normal root execing a process. 769 * 770 * Number 1 above might fail if you don't have a full bset, but I think 771 * that is interesting information to audit. 772 * 773 * A number of other conditions require logging: 774 * 2) something prevented setuid root getting all caps 775 * 3) non-setuid root gets fcaps 776 * 4) non-setuid root gets ambient 777 */ 778 static inline bool nonroot_raised_pE(struct cred *new, const struct cred *old, 779 kuid_t root, bool has_fcap) 780 { 781 bool ret = false; 782 783 if ((__cap_grew(effective, ambient, new) && 784 !(__cap_full(effective, new) && 785 (__is_eff(root, new) || __is_real(root, new)) && 786 root_privileged())) || 787 (root_privileged() && 788 __is_suid(root, new) && 789 !__cap_full(effective, new)) || 790 (!__is_setuid(new, old) && 791 ((has_fcap && 792 __cap_gained(permitted, new, old)) || 793 __cap_gained(ambient, new, old)))) 794 795 ret = true; 796 797 return ret; 798 } 799 800 /** 801 * cap_bprm_creds_from_file - Set up the proposed credentials for execve(). 802 * @bprm: The execution parameters, including the proposed creds 803 * @file: The file to pull the credentials from 804 * 805 * Set up the proposed credentials for a new execution context being 806 * constructed by execve(). The proposed creds in @bprm->cred is altered, 807 * which won't take effect immediately. Returns 0 if successful, -ve on error. 808 */ 809 int cap_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file) 810 { 811 /* Process setpcap binaries and capabilities for uid 0 */ 812 const struct cred *old = current_cred(); 813 struct cred *new = bprm->cred; 814 bool effective = false, has_fcap = false, is_setid; 815 int ret; 816 kuid_t root_uid; 817 818 if (WARN_ON(!cap_ambient_invariant_ok(old))) 819 return -EPERM; 820 821 ret = get_file_caps(bprm, file, &effective, &has_fcap); 822 if (ret < 0) 823 return ret; 824 825 root_uid = make_kuid(new->user_ns, 0); 826 827 handle_privileged_root(bprm, has_fcap, &effective, root_uid); 828 829 /* if we have fs caps, clear dangerous personality flags */ 830 if (__cap_gained(permitted, new, old)) 831 bprm->per_clear |= PER_CLEAR_ON_SETID; 832 833 /* Don't let someone trace a set[ug]id/setpcap binary with the revised 834 * credentials unless they have the appropriate permit. 835 * 836 * In addition, if NO_NEW_PRIVS, then ensure we get no new privs. 837 */ 838 is_setid = __is_setuid(new, old) || __is_setgid(new, old); 839 840 if ((is_setid || __cap_gained(permitted, new, old)) && 841 ((bprm->unsafe & ~LSM_UNSAFE_PTRACE) || 842 !ptracer_capable(current, new->user_ns))) { 843 /* downgrade; they get no more than they had, and maybe less */ 844 if (!ns_capable(new->user_ns, CAP_SETUID) || 845 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) { 846 new->euid = new->uid; 847 new->egid = new->gid; 848 } 849 new->cap_permitted = cap_intersect(new->cap_permitted, 850 old->cap_permitted); 851 } 852 853 new->suid = new->fsuid = new->euid; 854 new->sgid = new->fsgid = new->egid; 855 856 /* File caps or setid cancels ambient. */ 857 if (has_fcap || is_setid) 858 cap_clear(new->cap_ambient); 859 860 /* 861 * Now that we've computed pA', update pP' to give: 862 * pP' = (X & fP) | (pI & fI) | pA' 863 */ 864 new->cap_permitted = cap_combine(new->cap_permitted, new->cap_ambient); 865 866 /* 867 * Set pE' = (fE ? pP' : pA'). Because pA' is zero if fE is set, 868 * this is the same as pE' = (fE ? pP' : 0) | pA'. 869 */ 870 if (effective) 871 new->cap_effective = new->cap_permitted; 872 else 873 new->cap_effective = new->cap_ambient; 874 875 if (WARN_ON(!cap_ambient_invariant_ok(new))) 876 return -EPERM; 877 878 if (nonroot_raised_pE(new, old, root_uid, has_fcap)) { 879 ret = audit_log_bprm_fcaps(bprm, new, old); 880 if (ret < 0) 881 return ret; 882 } 883 884 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS); 885 886 if (WARN_ON(!cap_ambient_invariant_ok(new))) 887 return -EPERM; 888 889 /* Check for privilege-elevated exec. */ 890 if (is_setid || 891 (!__is_real(root_uid, new) && 892 (effective || 893 __cap_grew(permitted, ambient, new)))) 894 bprm->secureexec = 1; 895 896 return 0; 897 } 898 899 /** 900 * cap_inode_setxattr - Determine whether an xattr may be altered 901 * @dentry: The inode/dentry being altered 902 * @name: The name of the xattr to be changed 903 * @value: The value that the xattr will be changed to 904 * @size: The size of value 905 * @flags: The replacement flag 906 * 907 * Determine whether an xattr may be altered or set on an inode, returning 0 if 908 * permission is granted, -ve if denied. 909 * 910 * This is used to make sure security xattrs don't get updated or set by those 911 * who aren't privileged to do so. 912 */ 913 int cap_inode_setxattr(struct dentry *dentry, const char *name, 914 const void *value, size_t size, int flags) 915 { 916 struct user_namespace *user_ns = dentry->d_sb->s_user_ns; 917 918 /* Ignore non-security xattrs */ 919 if (strncmp(name, XATTR_SECURITY_PREFIX, 920 XATTR_SECURITY_PREFIX_LEN) != 0) 921 return 0; 922 923 /* 924 * For XATTR_NAME_CAPS the check will be done in 925 * cap_convert_nscap(), called by setxattr() 926 */ 927 if (strcmp(name, XATTR_NAME_CAPS) == 0) 928 return 0; 929 930 if (!ns_capable(user_ns, CAP_SYS_ADMIN)) 931 return -EPERM; 932 return 0; 933 } 934 935 /** 936 * cap_inode_removexattr - Determine whether an xattr may be removed 937 * @dentry: The inode/dentry being altered 938 * @name: The name of the xattr to be changed 939 * 940 * Determine whether an xattr may be removed from an inode, returning 0 if 941 * permission is granted, -ve if denied. 942 * 943 * This is used to make sure security xattrs don't get removed by those who 944 * aren't privileged to remove them. 945 */ 946 int cap_inode_removexattr(struct dentry *dentry, const char *name) 947 { 948 struct user_namespace *user_ns = dentry->d_sb->s_user_ns; 949 950 /* Ignore non-security xattrs */ 951 if (strncmp(name, XATTR_SECURITY_PREFIX, 952 XATTR_SECURITY_PREFIX_LEN) != 0) 953 return 0; 954 955 if (strcmp(name, XATTR_NAME_CAPS) == 0) { 956 /* security.capability gets namespaced */ 957 struct inode *inode = d_backing_inode(dentry); 958 if (!inode) 959 return -EINVAL; 960 if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP)) 961 return -EPERM; 962 return 0; 963 } 964 965 if (!ns_capable(user_ns, CAP_SYS_ADMIN)) 966 return -EPERM; 967 return 0; 968 } 969 970 /* 971 * cap_emulate_setxuid() fixes the effective / permitted capabilities of 972 * a process after a call to setuid, setreuid, or setresuid. 973 * 974 * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of 975 * {r,e,s}uid != 0, the permitted and effective capabilities are 976 * cleared. 977 * 978 * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective 979 * capabilities of the process are cleared. 980 * 981 * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective 982 * capabilities are set to the permitted capabilities. 983 * 984 * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should 985 * never happen. 986 * 987 * -astor 988 * 989 * cevans - New behaviour, Oct '99 990 * A process may, via prctl(), elect to keep its capabilities when it 991 * calls setuid() and switches away from uid==0. Both permitted and 992 * effective sets will be retained. 993 * Without this change, it was impossible for a daemon to drop only some 994 * of its privilege. The call to setuid(!=0) would drop all privileges! 995 * Keeping uid 0 is not an option because uid 0 owns too many vital 996 * files.. 997 * Thanks to Olaf Kirch and Peter Benie for spotting this. 998 */ 999 static inline void cap_emulate_setxuid(struct cred *new, const struct cred *old) 1000 { 1001 kuid_t root_uid = make_kuid(old->user_ns, 0); 1002 1003 if ((uid_eq(old->uid, root_uid) || 1004 uid_eq(old->euid, root_uid) || 1005 uid_eq(old->suid, root_uid)) && 1006 (!uid_eq(new->uid, root_uid) && 1007 !uid_eq(new->euid, root_uid) && 1008 !uid_eq(new->suid, root_uid))) { 1009 if (!issecure(SECURE_KEEP_CAPS)) { 1010 cap_clear(new->cap_permitted); 1011 cap_clear(new->cap_effective); 1012 } 1013 1014 /* 1015 * Pre-ambient programs expect setresuid to nonroot followed 1016 * by exec to drop capabilities. We should make sure that 1017 * this remains the case. 1018 */ 1019 cap_clear(new->cap_ambient); 1020 } 1021 if (uid_eq(old->euid, root_uid) && !uid_eq(new->euid, root_uid)) 1022 cap_clear(new->cap_effective); 1023 if (!uid_eq(old->euid, root_uid) && uid_eq(new->euid, root_uid)) 1024 new->cap_effective = new->cap_permitted; 1025 } 1026 1027 /** 1028 * cap_task_fix_setuid - Fix up the results of setuid() call 1029 * @new: The proposed credentials 1030 * @old: The current task's current credentials 1031 * @flags: Indications of what has changed 1032 * 1033 * Fix up the results of setuid() call before the credential changes are 1034 * actually applied, returning 0 to grant the changes, -ve to deny them. 1035 */ 1036 int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags) 1037 { 1038 switch (flags) { 1039 case LSM_SETID_RE: 1040 case LSM_SETID_ID: 1041 case LSM_SETID_RES: 1042 /* juggle the capabilities to follow [RES]UID changes unless 1043 * otherwise suppressed */ 1044 if (!issecure(SECURE_NO_SETUID_FIXUP)) 1045 cap_emulate_setxuid(new, old); 1046 break; 1047 1048 case LSM_SETID_FS: 1049 /* juggle the capabilties to follow FSUID changes, unless 1050 * otherwise suppressed 1051 * 1052 * FIXME - is fsuser used for all CAP_FS_MASK capabilities? 1053 * if not, we might be a bit too harsh here. 1054 */ 1055 if (!issecure(SECURE_NO_SETUID_FIXUP)) { 1056 kuid_t root_uid = make_kuid(old->user_ns, 0); 1057 if (uid_eq(old->fsuid, root_uid) && !uid_eq(new->fsuid, root_uid)) 1058 new->cap_effective = 1059 cap_drop_fs_set(new->cap_effective); 1060 1061 if (!uid_eq(old->fsuid, root_uid) && uid_eq(new->fsuid, root_uid)) 1062 new->cap_effective = 1063 cap_raise_fs_set(new->cap_effective, 1064 new->cap_permitted); 1065 } 1066 break; 1067 1068 default: 1069 return -EINVAL; 1070 } 1071 1072 return 0; 1073 } 1074 1075 /* 1076 * Rationale: code calling task_setscheduler, task_setioprio, and 1077 * task_setnice, assumes that 1078 * . if capable(cap_sys_nice), then those actions should be allowed 1079 * . if not capable(cap_sys_nice), but acting on your own processes, 1080 * then those actions should be allowed 1081 * This is insufficient now since you can call code without suid, but 1082 * yet with increased caps. 1083 * So we check for increased caps on the target process. 1084 */ 1085 static int cap_safe_nice(struct task_struct *p) 1086 { 1087 int is_subset, ret = 0; 1088 1089 rcu_read_lock(); 1090 is_subset = cap_issubset(__task_cred(p)->cap_permitted, 1091 current_cred()->cap_permitted); 1092 if (!is_subset && !ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) 1093 ret = -EPERM; 1094 rcu_read_unlock(); 1095 1096 return ret; 1097 } 1098 1099 /** 1100 * cap_task_setscheduler - Detemine if scheduler policy change is permitted 1101 * @p: The task to affect 1102 * 1103 * Detemine if the requested scheduler policy change is permitted for the 1104 * specified task, returning 0 if permission is granted, -ve if denied. 1105 */ 1106 int cap_task_setscheduler(struct task_struct *p) 1107 { 1108 return cap_safe_nice(p); 1109 } 1110 1111 /** 1112 * cap_task_ioprio - Detemine if I/O priority change is permitted 1113 * @p: The task to affect 1114 * @ioprio: The I/O priority to set 1115 * 1116 * Detemine if the requested I/O priority change is permitted for the specified 1117 * task, returning 0 if permission is granted, -ve if denied. 1118 */ 1119 int cap_task_setioprio(struct task_struct *p, int ioprio) 1120 { 1121 return cap_safe_nice(p); 1122 } 1123 1124 /** 1125 * cap_task_ioprio - Detemine if task priority change is permitted 1126 * @p: The task to affect 1127 * @nice: The nice value to set 1128 * 1129 * Detemine if the requested task priority change is permitted for the 1130 * specified task, returning 0 if permission is granted, -ve if denied. 1131 */ 1132 int cap_task_setnice(struct task_struct *p, int nice) 1133 { 1134 return cap_safe_nice(p); 1135 } 1136 1137 /* 1138 * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from 1139 * the current task's bounding set. Returns 0 on success, -ve on error. 1140 */ 1141 static int cap_prctl_drop(unsigned long cap) 1142 { 1143 struct cred *new; 1144 1145 if (!ns_capable(current_user_ns(), CAP_SETPCAP)) 1146 return -EPERM; 1147 if (!cap_valid(cap)) 1148 return -EINVAL; 1149 1150 new = prepare_creds(); 1151 if (!new) 1152 return -ENOMEM; 1153 cap_lower(new->cap_bset, cap); 1154 return commit_creds(new); 1155 } 1156 1157 /** 1158 * cap_task_prctl - Implement process control functions for this security module 1159 * @option: The process control function requested 1160 * @arg2, @arg3, @arg4, @arg5: The argument data for this function 1161 * 1162 * Allow process control functions (sys_prctl()) to alter capabilities; may 1163 * also deny access to other functions not otherwise implemented here. 1164 * 1165 * Returns 0 or +ve on success, -ENOSYS if this function is not implemented 1166 * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM 1167 * modules will consider performing the function. 1168 */ 1169 int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, 1170 unsigned long arg4, unsigned long arg5) 1171 { 1172 const struct cred *old = current_cred(); 1173 struct cred *new; 1174 1175 switch (option) { 1176 case PR_CAPBSET_READ: 1177 if (!cap_valid(arg2)) 1178 return -EINVAL; 1179 return !!cap_raised(old->cap_bset, arg2); 1180 1181 case PR_CAPBSET_DROP: 1182 return cap_prctl_drop(arg2); 1183 1184 /* 1185 * The next four prctl's remain to assist with transitioning a 1186 * system from legacy UID=0 based privilege (when filesystem 1187 * capabilities are not in use) to a system using filesystem 1188 * capabilities only - as the POSIX.1e draft intended. 1189 * 1190 * Note: 1191 * 1192 * PR_SET_SECUREBITS = 1193 * issecure_mask(SECURE_KEEP_CAPS_LOCKED) 1194 * | issecure_mask(SECURE_NOROOT) 1195 * | issecure_mask(SECURE_NOROOT_LOCKED) 1196 * | issecure_mask(SECURE_NO_SETUID_FIXUP) 1197 * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED) 1198 * 1199 * will ensure that the current process and all of its 1200 * children will be locked into a pure 1201 * capability-based-privilege environment. 1202 */ 1203 case PR_SET_SECUREBITS: 1204 if ((((old->securebits & SECURE_ALL_LOCKS) >> 1) 1205 & (old->securebits ^ arg2)) /*[1]*/ 1206 || ((old->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/ 1207 || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/ 1208 || (cap_capable(current_cred(), 1209 current_cred()->user_ns, 1210 CAP_SETPCAP, 1211 CAP_OPT_NONE) != 0) /*[4]*/ 1212 /* 1213 * [1] no changing of bits that are locked 1214 * [2] no unlocking of locks 1215 * [3] no setting of unsupported bits 1216 * [4] doing anything requires privilege (go read about 1217 * the "sendmail capabilities bug") 1218 */ 1219 ) 1220 /* cannot change a locked bit */ 1221 return -EPERM; 1222 1223 new = prepare_creds(); 1224 if (!new) 1225 return -ENOMEM; 1226 new->securebits = arg2; 1227 return commit_creds(new); 1228 1229 case PR_GET_SECUREBITS: 1230 return old->securebits; 1231 1232 case PR_GET_KEEPCAPS: 1233 return !!issecure(SECURE_KEEP_CAPS); 1234 1235 case PR_SET_KEEPCAPS: 1236 if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */ 1237 return -EINVAL; 1238 if (issecure(SECURE_KEEP_CAPS_LOCKED)) 1239 return -EPERM; 1240 1241 new = prepare_creds(); 1242 if (!new) 1243 return -ENOMEM; 1244 if (arg2) 1245 new->securebits |= issecure_mask(SECURE_KEEP_CAPS); 1246 else 1247 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS); 1248 return commit_creds(new); 1249 1250 case PR_CAP_AMBIENT: 1251 if (arg2 == PR_CAP_AMBIENT_CLEAR_ALL) { 1252 if (arg3 | arg4 | arg5) 1253 return -EINVAL; 1254 1255 new = prepare_creds(); 1256 if (!new) 1257 return -ENOMEM; 1258 cap_clear(new->cap_ambient); 1259 return commit_creds(new); 1260 } 1261 1262 if (((!cap_valid(arg3)) | arg4 | arg5)) 1263 return -EINVAL; 1264 1265 if (arg2 == PR_CAP_AMBIENT_IS_SET) { 1266 return !!cap_raised(current_cred()->cap_ambient, arg3); 1267 } else if (arg2 != PR_CAP_AMBIENT_RAISE && 1268 arg2 != PR_CAP_AMBIENT_LOWER) { 1269 return -EINVAL; 1270 } else { 1271 if (arg2 == PR_CAP_AMBIENT_RAISE && 1272 (!cap_raised(current_cred()->cap_permitted, arg3) || 1273 !cap_raised(current_cred()->cap_inheritable, 1274 arg3) || 1275 issecure(SECURE_NO_CAP_AMBIENT_RAISE))) 1276 return -EPERM; 1277 1278 new = prepare_creds(); 1279 if (!new) 1280 return -ENOMEM; 1281 if (arg2 == PR_CAP_AMBIENT_RAISE) 1282 cap_raise(new->cap_ambient, arg3); 1283 else 1284 cap_lower(new->cap_ambient, arg3); 1285 return commit_creds(new); 1286 } 1287 1288 default: 1289 /* No functionality available - continue with default */ 1290 return -ENOSYS; 1291 } 1292 } 1293 1294 /** 1295 * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted 1296 * @mm: The VM space in which the new mapping is to be made 1297 * @pages: The size of the mapping 1298 * 1299 * Determine whether the allocation of a new virtual mapping by the current 1300 * task is permitted, returning 1 if permission is granted, 0 if not. 1301 */ 1302 int cap_vm_enough_memory(struct mm_struct *mm, long pages) 1303 { 1304 int cap_sys_admin = 0; 1305 1306 if (cap_capable(current_cred(), &init_user_ns, 1307 CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) == 0) 1308 cap_sys_admin = 1; 1309 1310 return cap_sys_admin; 1311 } 1312 1313 /* 1314 * cap_mmap_addr - check if able to map given addr 1315 * @addr: address attempting to be mapped 1316 * 1317 * If the process is attempting to map memory below dac_mmap_min_addr they need 1318 * CAP_SYS_RAWIO. The other parameters to this function are unused by the 1319 * capability security module. Returns 0 if this mapping should be allowed 1320 * -EPERM if not. 1321 */ 1322 int cap_mmap_addr(unsigned long addr) 1323 { 1324 int ret = 0; 1325 1326 if (addr < dac_mmap_min_addr) { 1327 ret = cap_capable(current_cred(), &init_user_ns, CAP_SYS_RAWIO, 1328 CAP_OPT_NONE); 1329 /* set PF_SUPERPRIV if it turns out we allow the low mmap */ 1330 if (ret == 0) 1331 current->flags |= PF_SUPERPRIV; 1332 } 1333 return ret; 1334 } 1335 1336 int cap_mmap_file(struct file *file, unsigned long reqprot, 1337 unsigned long prot, unsigned long flags) 1338 { 1339 return 0; 1340 } 1341 1342 #ifdef CONFIG_SECURITY 1343 1344 static struct security_hook_list capability_hooks[] __lsm_ro_after_init = { 1345 LSM_HOOK_INIT(capable, cap_capable), 1346 LSM_HOOK_INIT(settime, cap_settime), 1347 LSM_HOOK_INIT(ptrace_access_check, cap_ptrace_access_check), 1348 LSM_HOOK_INIT(ptrace_traceme, cap_ptrace_traceme), 1349 LSM_HOOK_INIT(capget, cap_capget), 1350 LSM_HOOK_INIT(capset, cap_capset), 1351 LSM_HOOK_INIT(bprm_creds_from_file, cap_bprm_creds_from_file), 1352 LSM_HOOK_INIT(inode_need_killpriv, cap_inode_need_killpriv), 1353 LSM_HOOK_INIT(inode_killpriv, cap_inode_killpriv), 1354 LSM_HOOK_INIT(inode_getsecurity, cap_inode_getsecurity), 1355 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr), 1356 LSM_HOOK_INIT(mmap_file, cap_mmap_file), 1357 LSM_HOOK_INIT(task_fix_setuid, cap_task_fix_setuid), 1358 LSM_HOOK_INIT(task_prctl, cap_task_prctl), 1359 LSM_HOOK_INIT(task_setscheduler, cap_task_setscheduler), 1360 LSM_HOOK_INIT(task_setioprio, cap_task_setioprio), 1361 LSM_HOOK_INIT(task_setnice, cap_task_setnice), 1362 LSM_HOOK_INIT(vm_enough_memory, cap_vm_enough_memory), 1363 }; 1364 1365 static int __init capability_init(void) 1366 { 1367 security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks), 1368 "capability"); 1369 return 0; 1370 } 1371 1372 DEFINE_LSM(capability) = { 1373 .name = "capability", 1374 .order = LSM_ORDER_FIRST, 1375 .init = capability_init, 1376 }; 1377 1378 #endif /* CONFIG_SECURITY */ 1379