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>
32 * If a non-root user executes a setuid-root binary in
33 * !secure(SECURE_NOROOT) mode, then we raise capabilities.
34 * However if fE is also set, then the intent is for only
35 * the file capabilities to be applied, and the setuid-root
36 * bit is left on either to change the uid (plausible) or
37 * to get full privilege on a kernel without file capabilities
38 * support. So in that case we do not raise capabilities.
40 * Warn if that happens, once per boot.
42 static void warn_setuid_and_fcaps_mixed(const char *fname
)
46 printk(KERN_INFO
"warning: `%s' has both setuid-root and"
47 " effective capabilities. Therefore not raising all"
48 " capabilities.\n", fname
);
53 int cap_netlink_send(struct sock
*sk
, struct sk_buff
*skb
)
58 int cap_netlink_recv(struct sk_buff
*skb
, int cap
)
60 if (!cap_raised(current_cap(), cap
))
64 EXPORT_SYMBOL(cap_netlink_recv
);
67 * cap_capable - Determine whether a task has a particular effective capability
68 * @tsk: The task to query
69 * @cred: The credentials to use
70 * @cap: The capability to check for
71 * @audit: Whether to write an audit message or not
73 * Determine whether the nominated task has the specified capability amongst
74 * its effective set, returning 0 if it does, -ve if it does not.
76 * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable()
77 * and has_capability() functions. That is, it has the reverse semantics:
78 * cap_has_capability() returns 0 when a task has a capability, but the
79 * kernel's capable() and has_capability() returns 1 for this case.
81 int cap_capable(struct task_struct
*tsk
, const struct cred
*cred
, int cap
,
84 return cap_raised(cred
->cap_effective
, cap
) ? 0 : -EPERM
;
88 * cap_settime - Determine whether the current process may set the system clock
89 * @ts: The time to set
90 * @tz: The timezone to set
92 * Determine whether the current process may set the system clock and timezone
93 * information, returning 0 if permission granted, -ve if denied.
95 int cap_settime(const struct timespec
*ts
, const struct timezone
*tz
)
97 if (!capable(CAP_SYS_TIME
))
103 * cap_ptrace_access_check - Determine whether the current process may access
105 * @child: The process to be accessed
106 * @mode: The mode of attachment.
108 * Determine whether a process may access another, returning 0 if permission
109 * granted, -ve if denied.
111 int cap_ptrace_access_check(struct task_struct
*child
, unsigned int mode
)
116 if (!cap_issubset(__task_cred(child
)->cap_permitted
,
117 current_cred()->cap_permitted
) &&
118 !capable(CAP_SYS_PTRACE
))
125 * cap_ptrace_traceme - Determine whether another process may trace the current
126 * @parent: The task proposed to be the tracer
128 * Determine whether the nominated task is permitted to trace the current
129 * process, returning 0 if permission is granted, -ve if denied.
131 int cap_ptrace_traceme(struct task_struct
*parent
)
136 if (!cap_issubset(current_cred()->cap_permitted
,
137 __task_cred(parent
)->cap_permitted
) &&
138 !has_capability(parent
, CAP_SYS_PTRACE
))
145 * cap_capget - Retrieve a task's capability sets
146 * @target: The task from which to retrieve the capability sets
147 * @effective: The place to record the effective set
148 * @inheritable: The place to record the inheritable set
149 * @permitted: The place to record the permitted set
151 * This function retrieves the capabilities of the nominated task and returns
152 * them to the caller.
154 int cap_capget(struct task_struct
*target
, kernel_cap_t
*effective
,
155 kernel_cap_t
*inheritable
, kernel_cap_t
*permitted
)
157 const struct cred
*cred
;
159 /* Derived from kernel/capability.c:sys_capget. */
161 cred
= __task_cred(target
);
162 *effective
= cred
->cap_effective
;
163 *inheritable
= cred
->cap_inheritable
;
164 *permitted
= cred
->cap_permitted
;
170 * Determine whether the inheritable capabilities are limited to the old
171 * permitted set. Returns 1 if they are limited, 0 if they are not.
173 static inline int cap_inh_is_capped(void)
176 /* they are so limited unless the current task has the CAP_SETPCAP
179 if (cap_capable(current
, current_cred(), CAP_SETPCAP
,
180 SECURITY_CAP_AUDIT
) == 0)
186 * cap_capset - Validate and apply proposed changes to current's capabilities
187 * @new: The proposed new credentials; alterations should be made here
188 * @old: The current task's current credentials
189 * @effective: A pointer to the proposed new effective capabilities set
190 * @inheritable: A pointer to the proposed new inheritable capabilities set
191 * @permitted: A pointer to the proposed new permitted capabilities set
193 * This function validates and applies a proposed mass change to the current
194 * process's capability sets. The changes are made to the proposed new
195 * credentials, and assuming no error, will be committed by the caller of LSM.
197 int cap_capset(struct cred
*new,
198 const struct cred
*old
,
199 const kernel_cap_t
*effective
,
200 const kernel_cap_t
*inheritable
,
201 const kernel_cap_t
*permitted
)
203 if (cap_inh_is_capped() &&
204 !cap_issubset(*inheritable
,
205 cap_combine(old
->cap_inheritable
,
206 old
->cap_permitted
)))
207 /* incapable of using this inheritable set */
210 if (!cap_issubset(*inheritable
,
211 cap_combine(old
->cap_inheritable
,
213 /* no new pI capabilities outside bounding set */
216 /* verify restrictions on target's new Permitted set */
217 if (!cap_issubset(*permitted
, old
->cap_permitted
))
220 /* verify the _new_Effective_ is a subset of the _new_Permitted_ */
221 if (!cap_issubset(*effective
, *permitted
))
224 new->cap_effective
= *effective
;
225 new->cap_inheritable
= *inheritable
;
226 new->cap_permitted
= *permitted
;
231 * Clear proposed capability sets for execve().
233 static inline void bprm_clear_caps(struct linux_binprm
*bprm
)
235 cap_clear(bprm
->cred
->cap_permitted
);
236 bprm
->cap_effective
= false;
240 * cap_inode_need_killpriv - Determine if inode change affects privileges
241 * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV
243 * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV
244 * affects the security markings on that inode, and if it is, should
245 * inode_killpriv() be invoked or the change rejected?
247 * Returns 0 if granted; +ve if granted, but inode_killpriv() is required; and
248 * -ve to deny the change.
250 int cap_inode_need_killpriv(struct dentry
*dentry
)
252 struct inode
*inode
= dentry
->d_inode
;
255 if (!inode
->i_op
->getxattr
)
258 error
= inode
->i_op
->getxattr(dentry
, XATTR_NAME_CAPS
, NULL
, 0);
265 * cap_inode_killpriv - Erase the security markings on an inode
266 * @dentry: The inode/dentry to alter
268 * Erase the privilege-enhancing security markings on an inode.
270 * Returns 0 if successful, -ve on error.
272 int cap_inode_killpriv(struct dentry
*dentry
)
274 struct inode
*inode
= dentry
->d_inode
;
276 if (!inode
->i_op
->removexattr
)
279 return inode
->i_op
->removexattr(dentry
, XATTR_NAME_CAPS
);
283 * Calculate the new process capability sets from the capability sets attached
286 static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data
*caps
,
287 struct linux_binprm
*bprm
,
290 struct cred
*new = bprm
->cred
;
294 if (caps
->magic_etc
& VFS_CAP_FLAGS_EFFECTIVE
)
297 CAP_FOR_EACH_U32(i
) {
298 __u32 permitted
= caps
->permitted
.cap
[i
];
299 __u32 inheritable
= caps
->inheritable
.cap
[i
];
302 * pP' = (X & fP) | (pI & fI)
304 new->cap_permitted
.cap
[i
] =
305 (new->cap_bset
.cap
[i
] & permitted
) |
306 (new->cap_inheritable
.cap
[i
] & inheritable
);
308 if (permitted
& ~new->cap_permitted
.cap
[i
])
309 /* insufficient to execute correctly */
314 * For legacy apps, with no internal support for recognizing they
315 * do not have enough capabilities, we return an error if they are
316 * missing some "forced" (aka file-permitted) capabilities.
318 return *effective
? ret
: 0;
322 * Extract the on-exec-apply capability sets for an executable file.
324 int get_vfs_caps_from_disk(const struct dentry
*dentry
, struct cpu_vfs_cap_data
*cpu_caps
)
326 struct inode
*inode
= dentry
->d_inode
;
330 struct vfs_cap_data caps
;
332 memset(cpu_caps
, 0, sizeof(struct cpu_vfs_cap_data
));
334 if (!inode
|| !inode
->i_op
->getxattr
)
337 size
= inode
->i_op
->getxattr((struct dentry
*)dentry
, XATTR_NAME_CAPS
, &caps
,
339 if (size
== -ENODATA
|| size
== -EOPNOTSUPP
)
340 /* no data, that's ok */
345 if (size
< sizeof(magic_etc
))
348 cpu_caps
->magic_etc
= magic_etc
= le32_to_cpu(caps
.magic_etc
);
350 switch (magic_etc
& VFS_CAP_REVISION_MASK
) {
351 case VFS_CAP_REVISION_1
:
352 if (size
!= XATTR_CAPS_SZ_1
)
354 tocopy
= VFS_CAP_U32_1
;
356 case VFS_CAP_REVISION_2
:
357 if (size
!= XATTR_CAPS_SZ_2
)
359 tocopy
= VFS_CAP_U32_2
;
365 CAP_FOR_EACH_U32(i
) {
368 cpu_caps
->permitted
.cap
[i
] = le32_to_cpu(caps
.data
[i
].permitted
);
369 cpu_caps
->inheritable
.cap
[i
] = le32_to_cpu(caps
.data
[i
].inheritable
);
376 * Attempt to get the on-exec apply capability sets for an executable file from
377 * its xattrs and, if present, apply them to the proposed credentials being
378 * constructed by execve().
380 static int get_file_caps(struct linux_binprm
*bprm
, bool *effective
)
382 struct dentry
*dentry
;
384 struct cpu_vfs_cap_data vcaps
;
386 bprm_clear_caps(bprm
);
388 if (!file_caps_enabled
)
391 if (bprm
->file
->f_vfsmnt
->mnt_flags
& MNT_NOSUID
)
394 dentry
= dget(bprm
->file
->f_dentry
);
396 rc
= get_vfs_caps_from_disk(dentry
, &vcaps
);
399 printk(KERN_NOTICE
"%s: get_vfs_caps_from_disk returned %d for %s\n",
400 __func__
, rc
, bprm
->filename
);
401 else if (rc
== -ENODATA
)
406 rc
= bprm_caps_from_vfs_caps(&vcaps
, bprm
, effective
);
408 printk(KERN_NOTICE
"%s: cap_from_disk returned %d for %s\n",
409 __func__
, rc
, bprm
->filename
);
414 bprm_clear_caps(bprm
);
420 * cap_bprm_set_creds - Set up the proposed credentials for execve().
421 * @bprm: The execution parameters, including the proposed creds
423 * Set up the proposed credentials for a new execution context being
424 * constructed by execve(). The proposed creds in @bprm->cred is altered,
425 * which won't take effect immediately. Returns 0 if successful, -ve on error.
427 int cap_bprm_set_creds(struct linux_binprm
*bprm
)
429 const struct cred
*old
= current_cred();
430 struct cred
*new = bprm
->cred
;
435 ret
= get_file_caps(bprm
, &effective
);
439 if (!issecure(SECURE_NOROOT
)) {
441 * If the legacy file capability is set, then don't set privs
442 * for a setuid root binary run by a non-root user. Do set it
443 * for a root user just to cause least surprise to an admin.
445 if (effective
&& new->uid
!= 0 && new->euid
== 0) {
446 warn_setuid_and_fcaps_mixed(bprm
->filename
);
450 * To support inheritance of root-permissions and suid-root
451 * executables under compatibility mode, we override the
452 * capability sets for the file.
454 * If only the real uid is 0, we do not set the effective bit.
456 if (new->euid
== 0 || new->uid
== 0) {
457 /* pP' = (cap_bset & ~0) | (pI & ~0) */
458 new->cap_permitted
= cap_combine(old
->cap_bset
,
459 old
->cap_inheritable
);
466 /* Don't let someone trace a set[ug]id/setpcap binary with the revised
467 * credentials unless they have the appropriate permit
469 if ((new->euid
!= old
->uid
||
470 new->egid
!= old
->gid
||
471 !cap_issubset(new->cap_permitted
, old
->cap_permitted
)) &&
472 bprm
->unsafe
& ~LSM_UNSAFE_PTRACE_CAP
) {
473 /* downgrade; they get no more than they had, and maybe less */
474 if (!capable(CAP_SETUID
)) {
475 new->euid
= new->uid
;
476 new->egid
= new->gid
;
478 new->cap_permitted
= cap_intersect(new->cap_permitted
,
482 new->suid
= new->fsuid
= new->euid
;
483 new->sgid
= new->fsgid
= new->egid
;
485 /* For init, we want to retain the capabilities set in the initial
486 * task. Thus we skip the usual capability rules
488 if (!is_global_init(current
)) {
490 new->cap_effective
= new->cap_permitted
;
492 cap_clear(new->cap_effective
);
494 bprm
->cap_effective
= effective
;
497 * Audit candidate if current->cap_effective is set
499 * We do not bother to audit if 3 things are true:
500 * 1) cap_effective has all caps
502 * 3) root is supposed to have all caps (SECURE_NOROOT)
503 * Since this is just a normal root execing a process.
505 * Number 1 above might fail if you don't have a full bset, but I think
506 * that is interesting information to audit.
508 if (!cap_isclear(new->cap_effective
)) {
509 if (!cap_issubset(CAP_FULL_SET
, new->cap_effective
) ||
510 new->euid
!= 0 || new->uid
!= 0 ||
511 issecure(SECURE_NOROOT
)) {
512 ret
= audit_log_bprm_fcaps(bprm
, new, old
);
518 new->securebits
&= ~issecure_mask(SECURE_KEEP_CAPS
);
523 * cap_bprm_secureexec - Determine whether a secure execution is required
524 * @bprm: The execution parameters
526 * Determine whether a secure execution is required, return 1 if it is, and 0
529 * The credentials have been committed by this point, and so are no longer
530 * available through @bprm->cred.
532 int cap_bprm_secureexec(struct linux_binprm
*bprm
)
534 const struct cred
*cred
= current_cred();
536 if (cred
->uid
!= 0) {
537 if (bprm
->cap_effective
)
539 if (!cap_isclear(cred
->cap_permitted
))
543 return (cred
->euid
!= cred
->uid
||
544 cred
->egid
!= cred
->gid
);
548 * cap_inode_setxattr - Determine whether an xattr may be altered
549 * @dentry: The inode/dentry being altered
550 * @name: The name of the xattr to be changed
551 * @value: The value that the xattr will be changed to
552 * @size: The size of value
553 * @flags: The replacement flag
555 * Determine whether an xattr may be altered or set on an inode, returning 0 if
556 * permission is granted, -ve if denied.
558 * This is used to make sure security xattrs don't get updated or set by those
559 * who aren't privileged to do so.
561 int cap_inode_setxattr(struct dentry
*dentry
, const char *name
,
562 const void *value
, size_t size
, int flags
)
564 if (!strcmp(name
, XATTR_NAME_CAPS
)) {
565 if (!capable(CAP_SETFCAP
))
570 if (!strncmp(name
, XATTR_SECURITY_PREFIX
,
571 sizeof(XATTR_SECURITY_PREFIX
) - 1) &&
572 !capable(CAP_SYS_ADMIN
))
578 * cap_inode_removexattr - Determine whether an xattr may be removed
579 * @dentry: The inode/dentry being altered
580 * @name: The name of the xattr to be changed
582 * Determine whether an xattr may be removed from an inode, returning 0 if
583 * permission is granted, -ve if denied.
585 * This is used to make sure security xattrs don't get removed by those who
586 * aren't privileged to remove them.
588 int cap_inode_removexattr(struct dentry
*dentry
, const char *name
)
590 if (!strcmp(name
, XATTR_NAME_CAPS
)) {
591 if (!capable(CAP_SETFCAP
))
596 if (!strncmp(name
, XATTR_SECURITY_PREFIX
,
597 sizeof(XATTR_SECURITY_PREFIX
) - 1) &&
598 !capable(CAP_SYS_ADMIN
))
604 * cap_emulate_setxuid() fixes the effective / permitted capabilities of
605 * a process after a call to setuid, setreuid, or setresuid.
607 * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of
608 * {r,e,s}uid != 0, the permitted and effective capabilities are
611 * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective
612 * capabilities of the process are cleared.
614 * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective
615 * capabilities are set to the permitted capabilities.
617 * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should
622 * cevans - New behaviour, Oct '99
623 * A process may, via prctl(), elect to keep its capabilities when it
624 * calls setuid() and switches away from uid==0. Both permitted and
625 * effective sets will be retained.
626 * Without this change, it was impossible for a daemon to drop only some
627 * of its privilege. The call to setuid(!=0) would drop all privileges!
628 * Keeping uid 0 is not an option because uid 0 owns too many vital
630 * Thanks to Olaf Kirch and Peter Benie for spotting this.
632 static inline void cap_emulate_setxuid(struct cred
*new, const struct cred
*old
)
634 if ((old
->uid
== 0 || old
->euid
== 0 || old
->suid
== 0) &&
635 (new->uid
!= 0 && new->euid
!= 0 && new->suid
!= 0) &&
636 !issecure(SECURE_KEEP_CAPS
)) {
637 cap_clear(new->cap_permitted
);
638 cap_clear(new->cap_effective
);
640 if (old
->euid
== 0 && new->euid
!= 0)
641 cap_clear(new->cap_effective
);
642 if (old
->euid
!= 0 && new->euid
== 0)
643 new->cap_effective
= new->cap_permitted
;
647 * cap_task_fix_setuid - Fix up the results of setuid() call
648 * @new: The proposed credentials
649 * @old: The current task's current credentials
650 * @flags: Indications of what has changed
652 * Fix up the results of setuid() call before the credential changes are
653 * actually applied, returning 0 to grant the changes, -ve to deny them.
655 int cap_task_fix_setuid(struct cred
*new, const struct cred
*old
, int flags
)
661 /* juggle the capabilities to follow [RES]UID changes unless
662 * otherwise suppressed */
663 if (!issecure(SECURE_NO_SETUID_FIXUP
))
664 cap_emulate_setxuid(new, old
);
668 /* juggle the capabilties to follow FSUID changes, unless
669 * otherwise suppressed
671 * FIXME - is fsuser used for all CAP_FS_MASK capabilities?
672 * if not, we might be a bit too harsh here.
674 if (!issecure(SECURE_NO_SETUID_FIXUP
)) {
675 if (old
->fsuid
== 0 && new->fsuid
!= 0)
677 cap_drop_fs_set(new->cap_effective
);
679 if (old
->fsuid
!= 0 && new->fsuid
== 0)
681 cap_raise_fs_set(new->cap_effective
,
694 * Rationale: code calling task_setscheduler, task_setioprio, and
695 * task_setnice, assumes that
696 * . if capable(cap_sys_nice), then those actions should be allowed
697 * . if not capable(cap_sys_nice), but acting on your own processes,
698 * then those actions should be allowed
699 * This is insufficient now since you can call code without suid, but
700 * yet with increased caps.
701 * So we check for increased caps on the target process.
703 static int cap_safe_nice(struct task_struct
*p
)
708 is_subset
= cap_issubset(__task_cred(p
)->cap_permitted
,
709 current_cred()->cap_permitted
);
712 if (!is_subset
&& !capable(CAP_SYS_NICE
))
718 * cap_task_setscheduler - Detemine if scheduler policy change is permitted
719 * @p: The task to affect
721 * Detemine if the requested scheduler policy change is permitted for the
722 * specified task, returning 0 if permission is granted, -ve if denied.
724 int cap_task_setscheduler(struct task_struct
*p
)
726 return cap_safe_nice(p
);
730 * cap_task_ioprio - Detemine if I/O priority change is permitted
731 * @p: The task to affect
732 * @ioprio: The I/O priority to set
734 * Detemine if the requested I/O priority change is permitted for the specified
735 * task, returning 0 if permission is granted, -ve if denied.
737 int cap_task_setioprio(struct task_struct
*p
, int ioprio
)
739 return cap_safe_nice(p
);
743 * cap_task_ioprio - Detemine if task priority change is permitted
744 * @p: The task to affect
745 * @nice: The nice value to set
747 * Detemine if the requested task priority change is permitted for the
748 * specified task, returning 0 if permission is granted, -ve if denied.
750 int cap_task_setnice(struct task_struct
*p
, int nice
)
752 return cap_safe_nice(p
);
756 * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from
757 * the current task's bounding set. Returns 0 on success, -ve on error.
759 static long cap_prctl_drop(struct cred
*new, unsigned long cap
)
761 if (!capable(CAP_SETPCAP
))
766 cap_lower(new->cap_bset
, cap
);
771 * cap_task_prctl - Implement process control functions for this security module
772 * @option: The process control function requested
773 * @arg2, @arg3, @arg4, @arg5: The argument data for this function
775 * Allow process control functions (sys_prctl()) to alter capabilities; may
776 * also deny access to other functions not otherwise implemented here.
778 * Returns 0 or +ve on success, -ENOSYS if this function is not implemented
779 * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM
780 * modules will consider performing the function.
782 int cap_task_prctl(int option
, unsigned long arg2
, unsigned long arg3
,
783 unsigned long arg4
, unsigned long arg5
)
788 new = prepare_creds();
793 case PR_CAPBSET_READ
:
795 if (!cap_valid(arg2
))
797 error
= !!cap_raised(new->cap_bset
, arg2
);
800 case PR_CAPBSET_DROP
:
801 error
= cap_prctl_drop(new, arg2
);
807 * The next four prctl's remain to assist with transitioning a
808 * system from legacy UID=0 based privilege (when filesystem
809 * capabilities are not in use) to a system using filesystem
810 * capabilities only - as the POSIX.1e draft intended.
814 * PR_SET_SECUREBITS =
815 * issecure_mask(SECURE_KEEP_CAPS_LOCKED)
816 * | issecure_mask(SECURE_NOROOT)
817 * | issecure_mask(SECURE_NOROOT_LOCKED)
818 * | issecure_mask(SECURE_NO_SETUID_FIXUP)
819 * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED)
821 * will ensure that the current process and all of its
822 * children will be locked into a pure
823 * capability-based-privilege environment.
825 case PR_SET_SECUREBITS
:
827 if ((((new->securebits
& SECURE_ALL_LOCKS
) >> 1)
828 & (new->securebits
^ arg2
)) /*[1]*/
829 || ((new->securebits
& SECURE_ALL_LOCKS
& ~arg2
)) /*[2]*/
830 || (arg2
& ~(SECURE_ALL_LOCKS
| SECURE_ALL_BITS
)) /*[3]*/
831 || (cap_capable(current
, current_cred(), CAP_SETPCAP
,
832 SECURITY_CAP_AUDIT
) != 0) /*[4]*/
834 * [1] no changing of bits that are locked
835 * [2] no unlocking of locks
836 * [3] no setting of unsupported bits
837 * [4] doing anything requires privilege (go read about
838 * the "sendmail capabilities bug")
841 /* cannot change a locked bit */
843 new->securebits
= arg2
;
846 case PR_GET_SECUREBITS
:
847 error
= new->securebits
;
850 case PR_GET_KEEPCAPS
:
851 if (issecure(SECURE_KEEP_CAPS
))
855 case PR_SET_KEEPCAPS
:
857 if (arg2
> 1) /* Note, we rely on arg2 being unsigned here */
860 if (issecure(SECURE_KEEP_CAPS_LOCKED
))
863 new->securebits
|= issecure_mask(SECURE_KEEP_CAPS
);
865 new->securebits
&= ~issecure_mask(SECURE_KEEP_CAPS
);
869 /* No functionality available - continue with default */
874 /* Functionality provided */
876 return commit_creds(new);
885 * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted
886 * @mm: The VM space in which the new mapping is to be made
887 * @pages: The size of the mapping
889 * Determine whether the allocation of a new virtual mapping by the current
890 * task is permitted, returning 0 if permission is granted, -ve if not.
892 int cap_vm_enough_memory(struct mm_struct
*mm
, long pages
)
894 int cap_sys_admin
= 0;
896 if (cap_capable(current
, current_cred(), CAP_SYS_ADMIN
,
897 SECURITY_CAP_NOAUDIT
) == 0)
899 return __vm_enough_memory(mm
, pages
, cap_sys_admin
);
903 * cap_file_mmap - check if able to map given addr
908 * @addr: address attempting to be mapped
911 * If the process is attempting to map memory below dac_mmap_min_addr they need
912 * CAP_SYS_RAWIO. The other parameters to this function are unused by the
913 * capability security module. Returns 0 if this mapping should be allowed
916 int cap_file_mmap(struct file
*file
, unsigned long reqprot
,
917 unsigned long prot
, unsigned long flags
,
918 unsigned long addr
, unsigned long addr_only
)
922 if (addr
< dac_mmap_min_addr
) {
923 ret
= cap_capable(current
, current_cred(), CAP_SYS_RAWIO
,
925 /* set PF_SUPERPRIV if it turns out we allow the low mmap */
927 current
->flags
|= PF_SUPERPRIV
;