1 /* Common capabilities, needed by capability.o.
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.
10 #include <linux/capability.h>
11 #include <linux/audit.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/security.h>
16 #include <linux/file.h>
18 #include <linux/mman.h>
19 #include <linux/pagemap.h>
20 #include <linux/swap.h>
21 #include <linux/skbuff.h>
22 #include <linux/netlink.h>
23 #include <linux/ptrace.h>
24 #include <linux/xattr.h>
25 #include <linux/hugetlb.h>
26 #include <linux/mount.h>
27 #include <linux/sched.h>
28 #include <linux/prctl.h>
29 #include <linux/securebits.h>
30 #include <linux/syslog.h>
32 #ifdef CONFIG_ANDROID_PARANOID_NETWORK
33 #include <linux/android_aid.h>
37 * If a non-root user executes a setuid-root binary in
38 * !secure(SECURE_NOROOT) mode, then we raise capabilities.
39 * However if fE is also set, then the intent is for only
40 * the file capabilities to be applied, and the setuid-root
41 * bit is left on either to change the uid (plausible) or
42 * to get full privilege on a kernel without file capabilities
43 * support. So in that case we do not raise capabilities.
45 * Warn if that happens, once per boot.
47 static void warn_setuid_and_fcaps_mixed(const char *fname)
51 printk(KERN_INFO "warning: `%s' has both setuid-root and"
52 " effective capabilities. Therefore not raising all"
53 " capabilities.\n", fname);
58 int cap_netlink_send(struct sock *sk, struct sk_buff *skb)
60 NETLINK_CB(skb).eff_cap = current_cap();
64 int cap_netlink_recv(struct sk_buff *skb, int cap)
66 if (!cap_raised(NETLINK_CB(skb).eff_cap, cap))
70 EXPORT_SYMBOL(cap_netlink_recv);
73 * cap_capable - Determine whether a task has a particular effective capability
74 * @tsk: The task to query
75 * @cred: The credentials to use
76 * @cap: The capability to check for
77 * @audit: Whether to write an audit message or not
79 * Determine whether the nominated task has the specified capability amongst
80 * its effective set, returning 0 if it does, -ve if it does not.
82 * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable()
83 * and has_capability() functions. That is, it has the reverse semantics:
84 * cap_has_capability() returns 0 when a task has a capability, but the
85 * kernel's capable() and has_capability() returns 1 for this case.
87 int cap_capable(struct task_struct *tsk, const struct cred *cred, int cap,
90 #ifdef CONFIG_ANDROID_PARANOID_NETWORK
91 if (cap == CAP_NET_RAW && in_egroup_p(AID_NET_RAW))
93 if (cap == CAP_NET_ADMIN && in_egroup_p(AID_NET_ADMIN))
96 return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM;
100 * cap_settime - Determine whether the current process may set the system clock
101 * @ts: The time to set
102 * @tz: The timezone to set
104 * Determine whether the current process may set the system clock and timezone
105 * information, returning 0 if permission granted, -ve if denied.
107 int cap_settime(struct timespec *ts, struct timezone *tz)
109 if (!capable(CAP_SYS_TIME))
115 * cap_ptrace_access_check - Determine whether the current process may access
117 * @child: The process to be accessed
118 * @mode: The mode of attachment.
120 * Determine whether a process may access another, returning 0 if permission
121 * granted, -ve if denied.
123 int cap_ptrace_access_check(struct task_struct *child, unsigned int mode)
128 if (!cap_issubset(__task_cred(child)->cap_permitted,
129 current_cred()->cap_permitted) &&
130 !capable(CAP_SYS_PTRACE))
137 * cap_ptrace_traceme - Determine whether another process may trace the current
138 * @parent: The task proposed to be the tracer
140 * Determine whether the nominated task is permitted to trace the current
141 * process, returning 0 if permission is granted, -ve if denied.
143 int cap_ptrace_traceme(struct task_struct *parent)
148 if (!cap_issubset(current_cred()->cap_permitted,
149 __task_cred(parent)->cap_permitted) &&
150 !has_capability(parent, CAP_SYS_PTRACE))
157 * cap_capget - Retrieve a task's capability sets
158 * @target: The task from which to retrieve the capability sets
159 * @effective: The place to record the effective set
160 * @inheritable: The place to record the inheritable set
161 * @permitted: The place to record the permitted set
163 * This function retrieves the capabilities of the nominated task and returns
164 * them to the caller.
166 int cap_capget(struct task_struct *target, kernel_cap_t *effective,
167 kernel_cap_t *inheritable, kernel_cap_t *permitted)
169 const struct cred *cred;
171 /* Derived from kernel/capability.c:sys_capget. */
173 cred = __task_cred(target);
174 *effective = cred->cap_effective;
175 *inheritable = cred->cap_inheritable;
176 *permitted = cred->cap_permitted;
182 * Determine whether the inheritable capabilities are limited to the old
183 * permitted set. Returns 1 if they are limited, 0 if they are not.
185 static inline int cap_inh_is_capped(void)
188 /* they are so limited unless the current task has the CAP_SETPCAP
191 if (cap_capable(current, current_cred(), CAP_SETPCAP,
192 SECURITY_CAP_AUDIT) == 0)
198 * cap_capset - Validate and apply proposed changes to current's capabilities
199 * @new: The proposed new credentials; alterations should be made here
200 * @old: The current task's current credentials
201 * @effective: A pointer to the proposed new effective capabilities set
202 * @inheritable: A pointer to the proposed new inheritable capabilities set
203 * @permitted: A pointer to the proposed new permitted capabilities set
205 * This function validates and applies a proposed mass change to the current
206 * process's capability sets. The changes are made to the proposed new
207 * credentials, and assuming no error, will be committed by the caller of LSM.
209 int cap_capset(struct cred *new,
210 const struct cred *old,
211 const kernel_cap_t *effective,
212 const kernel_cap_t *inheritable,
213 const kernel_cap_t *permitted)
215 if (cap_inh_is_capped() &&
216 !cap_issubset(*inheritable,
217 cap_combine(old->cap_inheritable,
218 old->cap_permitted)))
219 /* incapable of using this inheritable set */
222 if (!cap_issubset(*inheritable,
223 cap_combine(old->cap_inheritable,
225 /* no new pI capabilities outside bounding set */
228 /* verify restrictions on target's new Permitted set */
229 if (!cap_issubset(*permitted, old->cap_permitted))
232 /* verify the _new_Effective_ is a subset of the _new_Permitted_ */
233 if (!cap_issubset(*effective, *permitted))
236 new->cap_effective = *effective;
237 new->cap_inheritable = *inheritable;
238 new->cap_permitted = *permitted;
243 * Clear proposed capability sets for execve().
245 static inline void bprm_clear_caps(struct linux_binprm *bprm)
247 cap_clear(bprm->cred->cap_permitted);
248 bprm->cap_effective = false;
252 * cap_inode_need_killpriv - Determine if inode change affects privileges
253 * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV
255 * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV
256 * affects the security markings on that inode, and if it is, should
257 * inode_killpriv() be invoked or the change rejected?
259 * Returns 0 if granted; +ve if granted, but inode_killpriv() is required; and
260 * -ve to deny the change.
262 int cap_inode_need_killpriv(struct dentry *dentry)
264 struct inode *inode = dentry->d_inode;
267 if (!inode->i_op->getxattr)
270 error = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0);
277 * cap_inode_killpriv - Erase the security markings on an inode
278 * @dentry: The inode/dentry to alter
280 * Erase the privilege-enhancing security markings on an inode.
282 * Returns 0 if successful, -ve on error.
284 int cap_inode_killpriv(struct dentry *dentry)
286 struct inode *inode = dentry->d_inode;
288 if (!inode->i_op->removexattr)
291 return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS);
295 * Calculate the new process capability sets from the capability sets attached
298 static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps,
299 struct linux_binprm *bprm,
302 struct cred *new = bprm->cred;
306 if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE)
309 CAP_FOR_EACH_U32(i) {
310 __u32 permitted = caps->permitted.cap[i];
311 __u32 inheritable = caps->inheritable.cap[i];
314 * pP' = (X & fP) | (pI & fI)
316 new->cap_permitted.cap[i] =
317 (new->cap_bset.cap[i] & permitted) |
318 (new->cap_inheritable.cap[i] & inheritable);
320 if (permitted & ~new->cap_permitted.cap[i])
321 /* insufficient to execute correctly */
326 * For legacy apps, with no internal support for recognizing they
327 * do not have enough capabilities, we return an error if they are
328 * missing some "forced" (aka file-permitted) capabilities.
330 return *effective ? ret : 0;
334 * Extract the on-exec-apply capability sets for an executable file.
336 int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps)
338 struct inode *inode = dentry->d_inode;
342 struct vfs_cap_data caps;
344 memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data));
346 if (!inode || !inode->i_op->getxattr)
349 size = inode->i_op->getxattr((struct dentry *)dentry, XATTR_NAME_CAPS, &caps,
351 if (size == -ENODATA || size == -EOPNOTSUPP)
352 /* no data, that's ok */
357 if (size < sizeof(magic_etc))
360 cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps.magic_etc);
362 switch (magic_etc & VFS_CAP_REVISION_MASK) {
363 case VFS_CAP_REVISION_1:
364 if (size != XATTR_CAPS_SZ_1)
366 tocopy = VFS_CAP_U32_1;
368 case VFS_CAP_REVISION_2:
369 if (size != XATTR_CAPS_SZ_2)
371 tocopy = VFS_CAP_U32_2;
377 CAP_FOR_EACH_U32(i) {
380 cpu_caps->permitted.cap[i] = le32_to_cpu(caps.data[i].permitted);
381 cpu_caps->inheritable.cap[i] = le32_to_cpu(caps.data[i].inheritable);
388 * Attempt to get the on-exec apply capability sets for an executable file from
389 * its xattrs and, if present, apply them to the proposed credentials being
390 * constructed by execve().
392 static int get_file_caps(struct linux_binprm *bprm, bool *effective)
394 struct dentry *dentry;
396 struct cpu_vfs_cap_data vcaps;
398 bprm_clear_caps(bprm);
400 if (!file_caps_enabled)
403 if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
406 dentry = dget(bprm->file->f_dentry);
408 rc = get_vfs_caps_from_disk(dentry, &vcaps);
411 printk(KERN_NOTICE "%s: get_vfs_caps_from_disk returned %d for %s\n",
412 __func__, rc, bprm->filename);
413 else if (rc == -ENODATA)
418 rc = bprm_caps_from_vfs_caps(&vcaps, bprm, effective);
420 printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n",
421 __func__, rc, bprm->filename);
426 bprm_clear_caps(bprm);
432 * cap_bprm_set_creds - Set up the proposed credentials for execve().
433 * @bprm: The execution parameters, including the proposed creds
435 * Set up the proposed credentials for a new execution context being
436 * constructed by execve(). The proposed creds in @bprm->cred is altered,
437 * which won't take effect immediately. Returns 0 if successful, -ve on error.
439 int cap_bprm_set_creds(struct linux_binprm *bprm)
441 const struct cred *old = current_cred();
442 struct cred *new = bprm->cred;
447 ret = get_file_caps(bprm, &effective);
451 if (!issecure(SECURE_NOROOT)) {
453 * If the legacy file capability is set, then don't set privs
454 * for a setuid root binary run by a non-root user. Do set it
455 * for a root user just to cause least surprise to an admin.
457 if (effective && new->uid != 0 && new->euid == 0) {
458 warn_setuid_and_fcaps_mixed(bprm->filename);
462 * To support inheritance of root-permissions and suid-root
463 * executables under compatibility mode, we override the
464 * capability sets for the file.
466 * If only the real uid is 0, we do not set the effective bit.
468 if (new->euid == 0 || new->uid == 0) {
469 /* pP' = (cap_bset & ~0) | (pI & ~0) */
470 new->cap_permitted = cap_combine(old->cap_bset,
471 old->cap_inheritable);
478 /* Don't let someone trace a set[ug]id/setpcap binary with the revised
479 * credentials unless they have the appropriate permit
481 if ((new->euid != old->uid ||
482 new->egid != old->gid ||
483 !cap_issubset(new->cap_permitted, old->cap_permitted)) &&
484 bprm->unsafe & ~LSM_UNSAFE_PTRACE_CAP) {
485 /* downgrade; they get no more than they had, and maybe less */
486 if (!capable(CAP_SETUID)) {
487 new->euid = new->uid;
488 new->egid = new->gid;
490 new->cap_permitted = cap_intersect(new->cap_permitted,
494 new->suid = new->fsuid = new->euid;
495 new->sgid = new->fsgid = new->egid;
497 /* For init, we want to retain the capabilities set in the initial
498 * task. Thus we skip the usual capability rules
500 if (!is_global_init(current)) {
502 new->cap_effective = new->cap_permitted;
504 cap_clear(new->cap_effective);
506 bprm->cap_effective = effective;
509 * Audit candidate if current->cap_effective is set
511 * We do not bother to audit if 3 things are true:
512 * 1) cap_effective has all caps
514 * 3) root is supposed to have all caps (SECURE_NOROOT)
515 * Since this is just a normal root execing a process.
517 * Number 1 above might fail if you don't have a full bset, but I think
518 * that is interesting information to audit.
520 if (!cap_isclear(new->cap_effective)) {
521 if (!cap_issubset(CAP_FULL_SET, new->cap_effective) ||
522 new->euid != 0 || new->uid != 0 ||
523 issecure(SECURE_NOROOT)) {
524 ret = audit_log_bprm_fcaps(bprm, new, old);
530 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
535 * cap_bprm_secureexec - Determine whether a secure execution is required
536 * @bprm: The execution parameters
538 * Determine whether a secure execution is required, return 1 if it is, and 0
541 * The credentials have been committed by this point, and so are no longer
542 * available through @bprm->cred.
544 int cap_bprm_secureexec(struct linux_binprm *bprm)
546 const struct cred *cred = current_cred();
548 if (cred->uid != 0) {
549 if (bprm->cap_effective)
551 if (!cap_isclear(cred->cap_permitted))
555 return (cred->euid != cred->uid ||
556 cred->egid != cred->gid);
560 * cap_inode_setxattr - Determine whether an xattr may be altered
561 * @dentry: The inode/dentry being altered
562 * @name: The name of the xattr to be changed
563 * @value: The value that the xattr will be changed to
564 * @size: The size of value
565 * @flags: The replacement flag
567 * Determine whether an xattr may be altered or set on an inode, returning 0 if
568 * permission is granted, -ve if denied.
570 * This is used to make sure security xattrs don't get updated or set by those
571 * who aren't privileged to do so.
573 int cap_inode_setxattr(struct dentry *dentry, const char *name,
574 const void *value, size_t size, int flags)
576 if (!strcmp(name, XATTR_NAME_CAPS)) {
577 if (!capable(CAP_SETFCAP))
582 if (!strncmp(name, XATTR_SECURITY_PREFIX,
583 sizeof(XATTR_SECURITY_PREFIX) - 1) &&
584 !capable(CAP_SYS_ADMIN))
590 * cap_inode_removexattr - Determine whether an xattr may be removed
591 * @dentry: The inode/dentry being altered
592 * @name: The name of the xattr to be changed
594 * Determine whether an xattr may be removed from an inode, returning 0 if
595 * permission is granted, -ve if denied.
597 * This is used to make sure security xattrs don't get removed by those who
598 * aren't privileged to remove them.
600 int cap_inode_removexattr(struct dentry *dentry, const char *name)
602 if (!strcmp(name, XATTR_NAME_CAPS)) {
603 if (!capable(CAP_SETFCAP))
608 if (!strncmp(name, XATTR_SECURITY_PREFIX,
609 sizeof(XATTR_SECURITY_PREFIX) - 1) &&
610 !capable(CAP_SYS_ADMIN))
616 * cap_emulate_setxuid() fixes the effective / permitted capabilities of
617 * a process after a call to setuid, setreuid, or setresuid.
619 * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of
620 * {r,e,s}uid != 0, the permitted and effective capabilities are
623 * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective
624 * capabilities of the process are cleared.
626 * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective
627 * capabilities are set to the permitted capabilities.
629 * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should
634 * cevans - New behaviour, Oct '99
635 * A process may, via prctl(), elect to keep its capabilities when it
636 * calls setuid() and switches away from uid==0. Both permitted and
637 * effective sets will be retained.
638 * Without this change, it was impossible for a daemon to drop only some
639 * of its privilege. The call to setuid(!=0) would drop all privileges!
640 * Keeping uid 0 is not an option because uid 0 owns too many vital
642 * Thanks to Olaf Kirch and Peter Benie for spotting this.
644 static inline void cap_emulate_setxuid(struct cred *new, const struct cred *old)
646 if ((old->uid == 0 || old->euid == 0 || old->suid == 0) &&
647 (new->uid != 0 && new->euid != 0 && new->suid != 0) &&
648 !issecure(SECURE_KEEP_CAPS)) {
649 cap_clear(new->cap_permitted);
650 cap_clear(new->cap_effective);
652 if (old->euid == 0 && new->euid != 0)
653 cap_clear(new->cap_effective);
654 if (old->euid != 0 && new->euid == 0)
655 new->cap_effective = new->cap_permitted;
659 * cap_task_fix_setuid - Fix up the results of setuid() call
660 * @new: The proposed credentials
661 * @old: The current task's current credentials
662 * @flags: Indications of what has changed
664 * Fix up the results of setuid() call before the credential changes are
665 * actually applied, returning 0 to grant the changes, -ve to deny them.
667 int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags)
673 /* juggle the capabilities to follow [RES]UID changes unless
674 * otherwise suppressed */
675 if (!issecure(SECURE_NO_SETUID_FIXUP))
676 cap_emulate_setxuid(new, old);
680 /* juggle the capabilties to follow FSUID changes, unless
681 * otherwise suppressed
683 * FIXME - is fsuser used for all CAP_FS_MASK capabilities?
684 * if not, we might be a bit too harsh here.
686 if (!issecure(SECURE_NO_SETUID_FIXUP)) {
687 if (old->fsuid == 0 && new->fsuid != 0)
689 cap_drop_fs_set(new->cap_effective);
691 if (old->fsuid != 0 && new->fsuid == 0)
693 cap_raise_fs_set(new->cap_effective,
706 * Rationale: code calling task_setscheduler, task_setioprio, and
707 * task_setnice, assumes that
708 * . if capable(cap_sys_nice), then those actions should be allowed
709 * . if not capable(cap_sys_nice), but acting on your own processes,
710 * then those actions should be allowed
711 * This is insufficient now since you can call code without suid, but
712 * yet with increased caps.
713 * So we check for increased caps on the target process.
715 static int cap_safe_nice(struct task_struct *p)
720 is_subset = cap_issubset(__task_cred(p)->cap_permitted,
721 current_cred()->cap_permitted);
724 if (!is_subset && !capable(CAP_SYS_NICE))
730 * cap_task_setscheduler - Detemine if scheduler policy change is permitted
731 * @p: The task to affect
732 * @policy: The policy to effect
733 * @lp: The parameters to the scheduling policy
735 * Detemine if the requested scheduler policy change is permitted for the
736 * specified task, returning 0 if permission is granted, -ve if denied.
738 int cap_task_setscheduler(struct task_struct *p, int policy,
739 struct sched_param *lp)
741 return cap_safe_nice(p);
745 * cap_task_ioprio - Detemine if I/O priority change is permitted
746 * @p: The task to affect
747 * @ioprio: The I/O priority to set
749 * Detemine if the requested I/O priority change is permitted for the specified
750 * task, returning 0 if permission is granted, -ve if denied.
752 int cap_task_setioprio(struct task_struct *p, int ioprio)
754 return cap_safe_nice(p);
758 * cap_task_ioprio - Detemine if task priority change is permitted
759 * @p: The task to affect
760 * @nice: The nice value to set
762 * Detemine if the requested task priority change is permitted for the
763 * specified task, returning 0 if permission is granted, -ve if denied.
765 int cap_task_setnice(struct task_struct *p, int nice)
767 return cap_safe_nice(p);
771 * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from
772 * the current task's bounding set. Returns 0 on success, -ve on error.
774 static long cap_prctl_drop(struct cred *new, unsigned long cap)
776 if (!capable(CAP_SETPCAP))
781 cap_lower(new->cap_bset, cap);
786 * cap_task_prctl - Implement process control functions for this security module
787 * @option: The process control function requested
788 * @arg2, @arg3, @arg4, @arg5: The argument data for this function
790 * Allow process control functions (sys_prctl()) to alter capabilities; may
791 * also deny access to other functions not otherwise implemented here.
793 * Returns 0 or +ve on success, -ENOSYS if this function is not implemented
794 * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM
795 * modules will consider performing the function.
797 int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
798 unsigned long arg4, unsigned long arg5)
803 new = prepare_creds();
808 case PR_CAPBSET_READ:
810 if (!cap_valid(arg2))
812 error = !!cap_raised(new->cap_bset, arg2);
815 case PR_CAPBSET_DROP:
816 error = cap_prctl_drop(new, arg2);
822 * The next four prctl's remain to assist with transitioning a
823 * system from legacy UID=0 based privilege (when filesystem
824 * capabilities are not in use) to a system using filesystem
825 * capabilities only - as the POSIX.1e draft intended.
829 * PR_SET_SECUREBITS =
830 * issecure_mask(SECURE_KEEP_CAPS_LOCKED)
831 * | issecure_mask(SECURE_NOROOT)
832 * | issecure_mask(SECURE_NOROOT_LOCKED)
833 * | issecure_mask(SECURE_NO_SETUID_FIXUP)
834 * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED)
836 * will ensure that the current process and all of its
837 * children will be locked into a pure
838 * capability-based-privilege environment.
840 case PR_SET_SECUREBITS:
842 if ((((new->securebits & SECURE_ALL_LOCKS) >> 1)
843 & (new->securebits ^ arg2)) /*[1]*/
844 || ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/
845 || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/
846 || (cap_capable(current, current_cred(), CAP_SETPCAP,
847 SECURITY_CAP_AUDIT) != 0) /*[4]*/
849 * [1] no changing of bits that are locked
850 * [2] no unlocking of locks
851 * [3] no setting of unsupported bits
852 * [4] doing anything requires privilege (go read about
853 * the "sendmail capabilities bug")
856 /* cannot change a locked bit */
858 new->securebits = arg2;
861 case PR_GET_SECUREBITS:
862 error = new->securebits;
865 case PR_GET_KEEPCAPS:
866 if (issecure(SECURE_KEEP_CAPS))
870 case PR_SET_KEEPCAPS:
872 if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */
875 if (issecure(SECURE_KEEP_CAPS_LOCKED))
878 new->securebits |= issecure_mask(SECURE_KEEP_CAPS);
880 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
884 /* No functionality available - continue with default */
889 /* Functionality provided */
891 return commit_creds(new);
900 * cap_syslog - Determine whether syslog function is permitted
901 * @type: Function requested
902 * @from_file: Whether this request came from an open file (i.e. /proc)
904 * Determine whether the current process is permitted to use a particular
905 * syslog function, returning 0 if permission is granted, -ve if not.
907 int cap_syslog(int type, bool from_file)
909 if (type != SYSLOG_ACTION_OPEN && from_file)
911 if ((type != SYSLOG_ACTION_READ_ALL &&
912 type != SYSLOG_ACTION_SIZE_BUFFER) && !capable(CAP_SYS_ADMIN))
918 * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted
919 * @mm: The VM space in which the new mapping is to be made
920 * @pages: The size of the mapping
922 * Determine whether the allocation of a new virtual mapping by the current
923 * task is permitted, returning 0 if permission is granted, -ve if not.
925 int cap_vm_enough_memory(struct mm_struct *mm, long pages)
927 int cap_sys_admin = 0;
929 if (cap_capable(current, current_cred(), CAP_SYS_ADMIN,
930 SECURITY_CAP_NOAUDIT) == 0)
932 return __vm_enough_memory(mm, pages, cap_sys_admin);
936 * cap_file_mmap - check if able to map given addr
941 * @addr: address attempting to be mapped
944 * If the process is attempting to map memory below dac_mmap_min_addr they need
945 * CAP_SYS_RAWIO. The other parameters to this function are unused by the
946 * capability security module. Returns 0 if this mapping should be allowed
949 int cap_file_mmap(struct file *file, unsigned long reqprot,
950 unsigned long prot, unsigned long flags,
951 unsigned long addr, unsigned long addr_only)
955 if (addr < dac_mmap_min_addr) {
956 ret = cap_capable(current, current_cred(), CAP_SYS_RAWIO,
958 /* set PF_SUPERPRIV if it turns out we allow the low mmap */
960 current->flags |= PF_SUPERPRIV;