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/user_namespace.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)
63 int cap_netlink_recv(struct sk_buff *skb, int cap)
65 if (!cap_raised(current_cap(), cap))
69 EXPORT_SYMBOL(cap_netlink_recv);
72 * cap_capable - Determine whether a task has a particular effective capability
73 * @tsk: The task to query
74 * @cred: The credentials to use
75 * @ns: The user namespace in which we need the capability
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,
88 struct user_namespace *targ_ns, int cap, int audit)
90 if (cap == CAP_NET_RAW && in_egroup_p(AID_NET_RAW))
92 if (cap == CAP_NET_ADMIN && in_egroup_p(AID_NET_ADMIN))
96 /* The creator of the user namespace has all caps. */
97 if (targ_ns != &init_user_ns && targ_ns->creator == cred->user)
100 /* Do we have the necessary capabilities? */
101 if (targ_ns == cred->user->user_ns)
102 return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM;
104 /* Have we tried all of the parent namespaces? */
105 if (targ_ns == &init_user_ns)
109 *If you have a capability in a parent user ns, then you have
110 * it over all children user namespaces as well.
112 targ_ns = targ_ns->creator->user_ns;
115 /* We never get here */
119 * cap_settime - Determine whether the current process may set the system clock
120 * @ts: The time to set
121 * @tz: The timezone to set
123 * Determine whether the current process may set the system clock and timezone
124 * information, returning 0 if permission granted, -ve if denied.
126 int cap_settime(const struct timespec *ts, const struct timezone *tz)
128 if (!capable(CAP_SYS_TIME))
134 * cap_ptrace_access_check - Determine whether the current process may access
136 * @child: The process to be accessed
137 * @mode: The mode of attachment.
139 * If we are in the same or an ancestor user_ns and have all the target
140 * task's capabilities, then ptrace access is allowed.
141 * If we have the ptrace capability to the target user_ns, then ptrace
145 * Determine whether a process may access another, returning 0 if permission
146 * granted, -ve if denied.
148 int cap_ptrace_access_check(struct task_struct *child, unsigned int mode)
151 const struct cred *cred, *child_cred;
154 cred = current_cred();
155 child_cred = __task_cred(child);
156 if (cred->user->user_ns == child_cred->user->user_ns &&
157 cap_issubset(child_cred->cap_permitted, cred->cap_permitted))
159 if (ns_capable(child_cred->user->user_ns, CAP_SYS_PTRACE))
168 * cap_ptrace_traceme - Determine whether another process may trace the current
169 * @parent: The task proposed to be the tracer
171 * If parent is in the same or an ancestor user_ns and has all current's
172 * capabilities, then ptrace access is allowed.
173 * If parent has the ptrace capability to current's user_ns, then ptrace
177 * Determine whether the nominated task is permitted to trace the current
178 * process, returning 0 if permission is granted, -ve if denied.
180 int cap_ptrace_traceme(struct task_struct *parent)
183 const struct cred *cred, *child_cred;
186 cred = __task_cred(parent);
187 child_cred = current_cred();
188 if (cred->user->user_ns == child_cred->user->user_ns &&
189 cap_issubset(child_cred->cap_permitted, cred->cap_permitted))
191 if (has_ns_capability(parent, child_cred->user->user_ns, CAP_SYS_PTRACE))
200 * cap_capget - Retrieve a task's capability sets
201 * @target: The task from which to retrieve the capability sets
202 * @effective: The place to record the effective set
203 * @inheritable: The place to record the inheritable set
204 * @permitted: The place to record the permitted set
206 * This function retrieves the capabilities of the nominated task and returns
207 * them to the caller.
209 int cap_capget(struct task_struct *target, kernel_cap_t *effective,
210 kernel_cap_t *inheritable, kernel_cap_t *permitted)
212 const struct cred *cred;
214 /* Derived from kernel/capability.c:sys_capget. */
216 cred = __task_cred(target);
217 *effective = cred->cap_effective;
218 *inheritable = cred->cap_inheritable;
219 *permitted = cred->cap_permitted;
225 * Determine whether the inheritable capabilities are limited to the old
226 * permitted set. Returns 1 if they are limited, 0 if they are not.
228 static inline int cap_inh_is_capped(void)
231 /* they are so limited unless the current task has the CAP_SETPCAP
234 if (cap_capable(current, current_cred(),
235 current_cred()->user->user_ns, CAP_SETPCAP,
236 SECURITY_CAP_AUDIT) == 0)
242 * cap_capset - Validate and apply proposed changes to current's capabilities
243 * @new: The proposed new credentials; alterations should be made here
244 * @old: The current task's current credentials
245 * @effective: A pointer to the proposed new effective capabilities set
246 * @inheritable: A pointer to the proposed new inheritable capabilities set
247 * @permitted: A pointer to the proposed new permitted capabilities set
249 * This function validates and applies a proposed mass change to the current
250 * process's capability sets. The changes are made to the proposed new
251 * credentials, and assuming no error, will be committed by the caller of LSM.
253 int cap_capset(struct cred *new,
254 const struct cred *old,
255 const kernel_cap_t *effective,
256 const kernel_cap_t *inheritable,
257 const kernel_cap_t *permitted)
259 if (cap_inh_is_capped() &&
260 !cap_issubset(*inheritable,
261 cap_combine(old->cap_inheritable,
262 old->cap_permitted)))
263 /* incapable of using this inheritable set */
266 if (!cap_issubset(*inheritable,
267 cap_combine(old->cap_inheritable,
269 /* no new pI capabilities outside bounding set */
272 /* verify restrictions on target's new Permitted set */
273 if (!cap_issubset(*permitted, old->cap_permitted))
276 /* verify the _new_Effective_ is a subset of the _new_Permitted_ */
277 if (!cap_issubset(*effective, *permitted))
280 new->cap_effective = *effective;
281 new->cap_inheritable = *inheritable;
282 new->cap_permitted = *permitted;
287 * Clear proposed capability sets for execve().
289 static inline void bprm_clear_caps(struct linux_binprm *bprm)
291 cap_clear(bprm->cred->cap_permitted);
292 bprm->cap_effective = false;
296 * cap_inode_need_killpriv - Determine if inode change affects privileges
297 * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV
299 * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV
300 * affects the security markings on that inode, and if it is, should
301 * inode_killpriv() be invoked or the change rejected?
303 * Returns 0 if granted; +ve if granted, but inode_killpriv() is required; and
304 * -ve to deny the change.
306 int cap_inode_need_killpriv(struct dentry *dentry)
308 struct inode *inode = dentry->d_inode;
311 if (!inode->i_op->getxattr)
314 error = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0);
321 * cap_inode_killpriv - Erase the security markings on an inode
322 * @dentry: The inode/dentry to alter
324 * Erase the privilege-enhancing security markings on an inode.
326 * Returns 0 if successful, -ve on error.
328 int cap_inode_killpriv(struct dentry *dentry)
330 struct inode *inode = dentry->d_inode;
332 if (!inode->i_op->removexattr)
335 return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS);
339 * Calculate the new process capability sets from the capability sets attached
342 static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps,
343 struct linux_binprm *bprm,
346 struct cred *new = bprm->cred;
350 if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE)
353 CAP_FOR_EACH_U32(i) {
354 __u32 permitted = caps->permitted.cap[i];
355 __u32 inheritable = caps->inheritable.cap[i];
358 * pP' = (X & fP) | (pI & fI)
360 new->cap_permitted.cap[i] =
361 (new->cap_bset.cap[i] & permitted) |
362 (new->cap_inheritable.cap[i] & inheritable);
364 if (permitted & ~new->cap_permitted.cap[i])
365 /* insufficient to execute correctly */
370 * For legacy apps, with no internal support for recognizing they
371 * do not have enough capabilities, we return an error if they are
372 * missing some "forced" (aka file-permitted) capabilities.
374 return *effective ? ret : 0;
378 * Extract the on-exec-apply capability sets for an executable file.
380 int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps)
382 struct inode *inode = dentry->d_inode;
386 struct vfs_cap_data caps;
388 memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data));
390 if (!inode || !inode->i_op->getxattr)
393 size = inode->i_op->getxattr((struct dentry *)dentry, XATTR_NAME_CAPS, &caps,
395 if (size == -ENODATA || size == -EOPNOTSUPP)
396 /* no data, that's ok */
401 if (size < sizeof(magic_etc))
404 cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps.magic_etc);
406 switch (magic_etc & VFS_CAP_REVISION_MASK) {
407 case VFS_CAP_REVISION_1:
408 if (size != XATTR_CAPS_SZ_1)
410 tocopy = VFS_CAP_U32_1;
412 case VFS_CAP_REVISION_2:
413 if (size != XATTR_CAPS_SZ_2)
415 tocopy = VFS_CAP_U32_2;
421 CAP_FOR_EACH_U32(i) {
424 cpu_caps->permitted.cap[i] = le32_to_cpu(caps.data[i].permitted);
425 cpu_caps->inheritable.cap[i] = le32_to_cpu(caps.data[i].inheritable);
432 * Attempt to get the on-exec apply capability sets for an executable file from
433 * its xattrs and, if present, apply them to the proposed credentials being
434 * constructed by execve().
436 static int get_file_caps(struct linux_binprm *bprm, bool *effective)
438 struct dentry *dentry;
440 struct cpu_vfs_cap_data vcaps;
442 bprm_clear_caps(bprm);
444 if (!file_caps_enabled)
447 if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
450 dentry = dget(bprm->file->f_dentry);
452 rc = get_vfs_caps_from_disk(dentry, &vcaps);
455 printk(KERN_NOTICE "%s: get_vfs_caps_from_disk returned %d for %s\n",
456 __func__, rc, bprm->filename);
457 else if (rc == -ENODATA)
462 rc = bprm_caps_from_vfs_caps(&vcaps, bprm, effective);
464 printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n",
465 __func__, rc, bprm->filename);
470 bprm_clear_caps(bprm);
476 * cap_bprm_set_creds - Set up the proposed credentials for execve().
477 * @bprm: The execution parameters, including the proposed creds
479 * Set up the proposed credentials for a new execution context being
480 * constructed by execve(). The proposed creds in @bprm->cred is altered,
481 * which won't take effect immediately. Returns 0 if successful, -ve on error.
483 int cap_bprm_set_creds(struct linux_binprm *bprm)
485 const struct cred *old = current_cred();
486 struct cred *new = bprm->cred;
491 ret = get_file_caps(bprm, &effective);
495 if (!issecure(SECURE_NOROOT)) {
497 * If the legacy file capability is set, then don't set privs
498 * for a setuid root binary run by a non-root user. Do set it
499 * for a root user just to cause least surprise to an admin.
501 if (effective && new->uid != 0 && new->euid == 0) {
502 warn_setuid_and_fcaps_mixed(bprm->filename);
506 * To support inheritance of root-permissions and suid-root
507 * executables under compatibility mode, we override the
508 * capability sets for the file.
510 * If only the real uid is 0, we do not set the effective bit.
512 if (new->euid == 0 || new->uid == 0) {
513 /* pP' = (cap_bset & ~0) | (pI & ~0) */
514 new->cap_permitted = cap_combine(old->cap_bset,
515 old->cap_inheritable);
522 /* Don't let someone trace a set[ug]id/setpcap binary with the revised
523 * credentials unless they have the appropriate permit
525 if ((new->euid != old->uid ||
526 new->egid != old->gid ||
527 !cap_issubset(new->cap_permitted, old->cap_permitted)) &&
528 bprm->unsafe & ~LSM_UNSAFE_PTRACE_CAP) {
529 /* downgrade; they get no more than they had, and maybe less */
530 if (!capable(CAP_SETUID)) {
531 new->euid = new->uid;
532 new->egid = new->gid;
534 new->cap_permitted = cap_intersect(new->cap_permitted,
538 new->suid = new->fsuid = new->euid;
539 new->sgid = new->fsgid = new->egid;
542 new->cap_effective = new->cap_permitted;
544 cap_clear(new->cap_effective);
545 bprm->cap_effective = effective;
548 * Audit candidate if current->cap_effective is set
550 * We do not bother to audit if 3 things are true:
551 * 1) cap_effective has all caps
553 * 3) root is supposed to have all caps (SECURE_NOROOT)
554 * Since this is just a normal root execing a process.
556 * Number 1 above might fail if you don't have a full bset, but I think
557 * that is interesting information to audit.
559 if (!cap_isclear(new->cap_effective)) {
560 if (!cap_issubset(CAP_FULL_SET, new->cap_effective) ||
561 new->euid != 0 || new->uid != 0 ||
562 issecure(SECURE_NOROOT)) {
563 ret = audit_log_bprm_fcaps(bprm, new, old);
569 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
574 * cap_bprm_secureexec - Determine whether a secure execution is required
575 * @bprm: The execution parameters
577 * Determine whether a secure execution is required, return 1 if it is, and 0
580 * The credentials have been committed by this point, and so are no longer
581 * available through @bprm->cred.
583 int cap_bprm_secureexec(struct linux_binprm *bprm)
585 const struct cred *cred = current_cred();
587 if (cred->uid != 0) {
588 if (bprm->cap_effective)
590 if (!cap_isclear(cred->cap_permitted))
594 return (cred->euid != cred->uid ||
595 cred->egid != cred->gid);
599 * cap_inode_setxattr - Determine whether an xattr may be altered
600 * @dentry: The inode/dentry being altered
601 * @name: The name of the xattr to be changed
602 * @value: The value that the xattr will be changed to
603 * @size: The size of value
604 * @flags: The replacement flag
606 * Determine whether an xattr may be altered or set on an inode, returning 0 if
607 * permission is granted, -ve if denied.
609 * This is used to make sure security xattrs don't get updated or set by those
610 * who aren't privileged to do so.
612 int cap_inode_setxattr(struct dentry *dentry, const char *name,
613 const void *value, size_t size, int flags)
615 if (!strcmp(name, XATTR_NAME_CAPS)) {
616 if (!capable(CAP_SETFCAP))
621 if (!strncmp(name, XATTR_SECURITY_PREFIX,
622 sizeof(XATTR_SECURITY_PREFIX) - 1) &&
623 !capable(CAP_SYS_ADMIN))
629 * cap_inode_removexattr - Determine whether an xattr may be removed
630 * @dentry: The inode/dentry being altered
631 * @name: The name of the xattr to be changed
633 * Determine whether an xattr may be removed from an inode, returning 0 if
634 * permission is granted, -ve if denied.
636 * This is used to make sure security xattrs don't get removed by those who
637 * aren't privileged to remove them.
639 int cap_inode_removexattr(struct dentry *dentry, const char *name)
641 if (!strcmp(name, XATTR_NAME_CAPS)) {
642 if (!capable(CAP_SETFCAP))
647 if (!strncmp(name, XATTR_SECURITY_PREFIX,
648 sizeof(XATTR_SECURITY_PREFIX) - 1) &&
649 !capable(CAP_SYS_ADMIN))
655 * cap_emulate_setxuid() fixes the effective / permitted capabilities of
656 * a process after a call to setuid, setreuid, or setresuid.
658 * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of
659 * {r,e,s}uid != 0, the permitted and effective capabilities are
662 * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective
663 * capabilities of the process are cleared.
665 * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective
666 * capabilities are set to the permitted capabilities.
668 * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should
673 * cevans - New behaviour, Oct '99
674 * A process may, via prctl(), elect to keep its capabilities when it
675 * calls setuid() and switches away from uid==0. Both permitted and
676 * effective sets will be retained.
677 * Without this change, it was impossible for a daemon to drop only some
678 * of its privilege. The call to setuid(!=0) would drop all privileges!
679 * Keeping uid 0 is not an option because uid 0 owns too many vital
681 * Thanks to Olaf Kirch and Peter Benie for spotting this.
683 static inline void cap_emulate_setxuid(struct cred *new, const struct cred *old)
685 if ((old->uid == 0 || old->euid == 0 || old->suid == 0) &&
686 (new->uid != 0 && new->euid != 0 && new->suid != 0) &&
687 !issecure(SECURE_KEEP_CAPS)) {
688 cap_clear(new->cap_permitted);
689 cap_clear(new->cap_effective);
691 if (old->euid == 0 && new->euid != 0)
692 cap_clear(new->cap_effective);
693 if (old->euid != 0 && new->euid == 0)
694 new->cap_effective = new->cap_permitted;
698 * cap_task_fix_setuid - Fix up the results of setuid() call
699 * @new: The proposed credentials
700 * @old: The current task's current credentials
701 * @flags: Indications of what has changed
703 * Fix up the results of setuid() call before the credential changes are
704 * actually applied, returning 0 to grant the changes, -ve to deny them.
706 int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags)
712 /* juggle the capabilities to follow [RES]UID changes unless
713 * otherwise suppressed */
714 if (!issecure(SECURE_NO_SETUID_FIXUP))
715 cap_emulate_setxuid(new, old);
719 /* juggle the capabilties to follow FSUID changes, unless
720 * otherwise suppressed
722 * FIXME - is fsuser used for all CAP_FS_MASK capabilities?
723 * if not, we might be a bit too harsh here.
725 if (!issecure(SECURE_NO_SETUID_FIXUP)) {
726 if (old->fsuid == 0 && new->fsuid != 0)
728 cap_drop_fs_set(new->cap_effective);
730 if (old->fsuid != 0 && new->fsuid == 0)
732 cap_raise_fs_set(new->cap_effective,
745 * Rationale: code calling task_setscheduler, task_setioprio, and
746 * task_setnice, assumes that
747 * . if capable(cap_sys_nice), then those actions should be allowed
748 * . if not capable(cap_sys_nice), but acting on your own processes,
749 * then those actions should be allowed
750 * This is insufficient now since you can call code without suid, but
751 * yet with increased caps.
752 * So we check for increased caps on the target process.
754 static int cap_safe_nice(struct task_struct *p)
759 is_subset = cap_issubset(__task_cred(p)->cap_permitted,
760 current_cred()->cap_permitted);
763 if (!is_subset && !capable(CAP_SYS_NICE))
769 * cap_task_setscheduler - Detemine if scheduler policy change is permitted
770 * @p: The task to affect
772 * Detemine if the requested scheduler policy change is permitted for the
773 * specified task, returning 0 if permission is granted, -ve if denied.
775 int cap_task_setscheduler(struct task_struct *p)
777 return cap_safe_nice(p);
781 * cap_task_ioprio - Detemine if I/O priority change is permitted
782 * @p: The task to affect
783 * @ioprio: The I/O priority to set
785 * Detemine if the requested I/O priority change is permitted for the specified
786 * task, returning 0 if permission is granted, -ve if denied.
788 int cap_task_setioprio(struct task_struct *p, int ioprio)
790 return cap_safe_nice(p);
794 * cap_task_ioprio - Detemine if task priority change is permitted
795 * @p: The task to affect
796 * @nice: The nice value to set
798 * Detemine if the requested task priority change is permitted for the
799 * specified task, returning 0 if permission is granted, -ve if denied.
801 int cap_task_setnice(struct task_struct *p, int nice)
803 return cap_safe_nice(p);
807 * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from
808 * the current task's bounding set. Returns 0 on success, -ve on error.
810 static long cap_prctl_drop(struct cred *new, unsigned long cap)
812 if (!capable(CAP_SETPCAP))
817 cap_lower(new->cap_bset, cap);
822 * cap_task_prctl - Implement process control functions for this security module
823 * @option: The process control function requested
824 * @arg2, @arg3, @arg4, @arg5: The argument data for this function
826 * Allow process control functions (sys_prctl()) to alter capabilities; may
827 * also deny access to other functions not otherwise implemented here.
829 * Returns 0 or +ve on success, -ENOSYS if this function is not implemented
830 * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM
831 * modules will consider performing the function.
833 int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
834 unsigned long arg4, unsigned long arg5)
839 new = prepare_creds();
844 case PR_CAPBSET_READ:
846 if (!cap_valid(arg2))
848 error = !!cap_raised(new->cap_bset, arg2);
851 case PR_CAPBSET_DROP:
852 error = cap_prctl_drop(new, arg2);
858 * The next four prctl's remain to assist with transitioning a
859 * system from legacy UID=0 based privilege (when filesystem
860 * capabilities are not in use) to a system using filesystem
861 * capabilities only - as the POSIX.1e draft intended.
865 * PR_SET_SECUREBITS =
866 * issecure_mask(SECURE_KEEP_CAPS_LOCKED)
867 * | issecure_mask(SECURE_NOROOT)
868 * | issecure_mask(SECURE_NOROOT_LOCKED)
869 * | issecure_mask(SECURE_NO_SETUID_FIXUP)
870 * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED)
872 * will ensure that the current process and all of its
873 * children will be locked into a pure
874 * capability-based-privilege environment.
876 case PR_SET_SECUREBITS:
878 if ((((new->securebits & SECURE_ALL_LOCKS) >> 1)
879 & (new->securebits ^ arg2)) /*[1]*/
880 || ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/
881 || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/
882 || (cap_capable(current, current_cred(),
883 current_cred()->user->user_ns, CAP_SETPCAP,
884 SECURITY_CAP_AUDIT) != 0) /*[4]*/
886 * [1] no changing of bits that are locked
887 * [2] no unlocking of locks
888 * [3] no setting of unsupported bits
889 * [4] doing anything requires privilege (go read about
890 * the "sendmail capabilities bug")
893 /* cannot change a locked bit */
895 new->securebits = arg2;
898 case PR_GET_SECUREBITS:
899 error = new->securebits;
902 case PR_GET_KEEPCAPS:
903 if (issecure(SECURE_KEEP_CAPS))
907 case PR_SET_KEEPCAPS:
909 if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */
912 if (issecure(SECURE_KEEP_CAPS_LOCKED))
915 new->securebits |= issecure_mask(SECURE_KEEP_CAPS);
917 new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
921 /* No functionality available - continue with default */
926 /* Functionality provided */
928 return commit_creds(new);
937 * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted
938 * @mm: The VM space in which the new mapping is to be made
939 * @pages: The size of the mapping
941 * Determine whether the allocation of a new virtual mapping by the current
942 * task is permitted, returning 0 if permission is granted, -ve if not.
944 int cap_vm_enough_memory(struct mm_struct *mm, long pages)
946 int cap_sys_admin = 0;
948 if (cap_capable(current, current_cred(), &init_user_ns, CAP_SYS_ADMIN,
949 SECURITY_CAP_NOAUDIT) == 0)
951 return __vm_enough_memory(mm, pages, cap_sys_admin);
955 * cap_file_mmap - check if able to map given addr
960 * @addr: address attempting to be mapped
963 * If the process is attempting to map memory below dac_mmap_min_addr they need
964 * CAP_SYS_RAWIO. The other parameters to this function are unused by the
965 * capability security module. Returns 0 if this mapping should be allowed
968 int cap_file_mmap(struct file *file, unsigned long reqprot,
969 unsigned long prot, unsigned long flags,
970 unsigned long addr, unsigned long addr_only)
974 if (addr < dac_mmap_min_addr) {
975 ret = cap_capable(current, current_cred(), &init_user_ns, CAP_SYS_RAWIO,
977 /* set PF_SUPERPRIV if it turns out we allow the low mmap */
979 current->flags |= PF_SUPERPRIV;