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1 /* Common capabilities, needed by capability.o and root_plug.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>
31 int cap_netlink_send(struct sock
*sk
, struct sk_buff
*skb
)
33 NETLINK_CB(skb
).eff_cap
= current_cap();
37 int cap_netlink_recv(struct sk_buff
*skb
, int cap
)
39 if (!cap_raised(NETLINK_CB(skb
).eff_cap
, cap
))
43 EXPORT_SYMBOL(cap_netlink_recv
);
46 * cap_capable - Determine whether a task has a particular effective capability
47 * @tsk: The task to query
48 * @cap: The capability to check for
49 * @audit: Whether to write an audit message or not
51 * Determine whether the nominated task has the specified capability amongst
52 * its effective set, returning 0 if it does, -ve if it does not.
54 * NOTE WELL: cap_capable() cannot be used like the kernel's capable()
55 * function. That is, it has the reverse semantics: cap_capable() returns 0
56 * when a task has a capability, but the kernel's capable() returns 1 for this
59 int cap_capable(struct task_struct
*tsk
, int cap
, int audit
)
63 /* Derived from include/linux/sched.h:capable. */
65 cap_raised
= cap_raised(__task_cred(tsk
)->cap_effective
, cap
);
67 return cap_raised
? 0 : -EPERM
;
71 * cap_settime - Determine whether the current process may set the system clock
72 * @ts: The time to set
73 * @tz: The timezone to set
75 * Determine whether the current process may set the system clock and timezone
76 * information, returning 0 if permission granted, -ve if denied.
78 int cap_settime(struct timespec
*ts
, struct timezone
*tz
)
80 if (!capable(CAP_SYS_TIME
))
86 * cap_ptrace_may_access - Determine whether the current process may access
88 * @child: The process to be accessed
89 * @mode: The mode of attachment.
91 * Determine whether a process may access another, returning 0 if permission
92 * granted, -ve if denied.
94 int cap_ptrace_may_access(struct task_struct
*child
, unsigned int mode
)
99 if (!cap_issubset(__task_cred(child
)->cap_permitted
,
100 current_cred()->cap_permitted
) &&
101 !capable(CAP_SYS_PTRACE
))
108 * cap_ptrace_traceme - Determine whether another process may trace the current
109 * @parent: The task proposed to be the tracer
111 * Determine whether the nominated task is permitted to trace the current
112 * process, returning 0 if permission is granted, -ve if denied.
114 int cap_ptrace_traceme(struct task_struct
*parent
)
119 if (!cap_issubset(current_cred()->cap_permitted
,
120 __task_cred(parent
)->cap_permitted
) &&
121 !has_capability(parent
, CAP_SYS_PTRACE
))
128 * cap_capget - Retrieve a task's capability sets
129 * @target: The task from which to retrieve the capability sets
130 * @effective: The place to record the effective set
131 * @inheritable: The place to record the inheritable set
132 * @permitted: The place to record the permitted set
134 * This function retrieves the capabilities of the nominated task and returns
135 * them to the caller.
137 int cap_capget(struct task_struct
*target
, kernel_cap_t
*effective
,
138 kernel_cap_t
*inheritable
, kernel_cap_t
*permitted
)
140 const struct cred
*cred
;
142 /* Derived from kernel/capability.c:sys_capget. */
144 cred
= __task_cred(target
);
145 *effective
= cred
->cap_effective
;
146 *inheritable
= cred
->cap_inheritable
;
147 *permitted
= cred
->cap_permitted
;
153 * Determine whether the inheritable capabilities are limited to the old
154 * permitted set. Returns 1 if they are limited, 0 if they are not.
156 static inline int cap_inh_is_capped(void)
158 #ifdef CONFIG_SECURITY_FILE_CAPABILITIES
160 /* they are so limited unless the current task has the CAP_SETPCAP
163 if (cap_capable(current
, CAP_SETPCAP
, SECURITY_CAP_AUDIT
) == 0)
170 * cap_capset - Validate and apply proposed changes to current's capabilities
171 * @new: The proposed new credentials; alterations should be made here
172 * @old: The current task's current credentials
173 * @effective: A pointer to the proposed new effective capabilities set
174 * @inheritable: A pointer to the proposed new inheritable capabilities set
175 * @permitted: A pointer to the proposed new permitted capabilities set
177 * This function validates and applies a proposed mass change to the current
178 * process's capability sets. The changes are made to the proposed new
179 * credentials, and assuming no error, will be committed by the caller of LSM.
181 int cap_capset(struct cred
*new,
182 const struct cred
*old
,
183 const kernel_cap_t
*effective
,
184 const kernel_cap_t
*inheritable
,
185 const kernel_cap_t
*permitted
)
187 if (cap_inh_is_capped() &&
188 !cap_issubset(*inheritable
,
189 cap_combine(old
->cap_inheritable
,
190 old
->cap_permitted
)))
191 /* incapable of using this inheritable set */
194 if (!cap_issubset(*inheritable
,
195 cap_combine(old
->cap_inheritable
,
197 /* no new pI capabilities outside bounding set */
200 /* verify restrictions on target's new Permitted set */
201 if (!cap_issubset(*permitted
, old
->cap_permitted
))
204 /* verify the _new_Effective_ is a subset of the _new_Permitted_ */
205 if (!cap_issubset(*effective
, *permitted
))
208 new->cap_effective
= *effective
;
209 new->cap_inheritable
= *inheritable
;
210 new->cap_permitted
= *permitted
;
215 * Clear proposed capability sets for execve().
217 static inline void bprm_clear_caps(struct linux_binprm
*bprm
)
219 cap_clear(bprm
->cred
->cap_permitted
);
220 bprm
->cap_effective
= false;
223 #ifdef CONFIG_SECURITY_FILE_CAPABILITIES
226 * cap_inode_need_killpriv - Determine if inode change affects privileges
227 * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV
229 * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV
230 * affects the security markings on that inode, and if it is, should
231 * inode_killpriv() be invoked or the change rejected?
233 * Returns 0 if granted; +ve if granted, but inode_killpriv() is required; and
234 * -ve to deny the change.
236 int cap_inode_need_killpriv(struct dentry
*dentry
)
238 struct inode
*inode
= dentry
->d_inode
;
241 if (!inode
->i_op
|| !inode
->i_op
->getxattr
)
244 error
= inode
->i_op
->getxattr(dentry
, XATTR_NAME_CAPS
, NULL
, 0);
251 * cap_inode_killpriv - Erase the security markings on an inode
252 * @dentry: The inode/dentry to alter
254 * Erase the privilege-enhancing security markings on an inode.
256 * Returns 0 if successful, -ve on error.
258 int cap_inode_killpriv(struct dentry
*dentry
)
260 struct inode
*inode
= dentry
->d_inode
;
262 if (!inode
->i_op
|| !inode
->i_op
->removexattr
)
265 return inode
->i_op
->removexattr(dentry
, XATTR_NAME_CAPS
);
269 * Calculate the new process capability sets from the capability sets attached
272 static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data
*caps
,
273 struct linux_binprm
*bprm
,
276 struct cred
*new = bprm
->cred
;
280 if (caps
->magic_etc
& VFS_CAP_FLAGS_EFFECTIVE
)
283 CAP_FOR_EACH_U32(i
) {
284 __u32 permitted
= caps
->permitted
.cap
[i
];
285 __u32 inheritable
= caps
->inheritable
.cap
[i
];
288 * pP' = (X & fP) | (pI & fI)
290 new->cap_permitted
.cap
[i
] =
291 (new->cap_bset
.cap
[i
] & permitted
) |
292 (new->cap_inheritable
.cap
[i
] & inheritable
);
294 if (permitted
& ~new->cap_permitted
.cap
[i
])
295 /* insufficient to execute correctly */
300 * For legacy apps, with no internal support for recognizing they
301 * do not have enough capabilities, we return an error if they are
302 * missing some "forced" (aka file-permitted) capabilities.
304 return *effective
? ret
: 0;
308 * Extract the on-exec-apply capability sets for an executable file.
310 int get_vfs_caps_from_disk(const struct dentry
*dentry
, struct cpu_vfs_cap_data
*cpu_caps
)
312 struct inode
*inode
= dentry
->d_inode
;
316 struct vfs_cap_data caps
;
318 memset(cpu_caps
, 0, sizeof(struct cpu_vfs_cap_data
));
320 if (!inode
|| !inode
->i_op
|| !inode
->i_op
->getxattr
)
323 size
= inode
->i_op
->getxattr((struct dentry
*)dentry
, XATTR_NAME_CAPS
, &caps
,
325 if (size
== -ENODATA
|| size
== -EOPNOTSUPP
)
326 /* no data, that's ok */
331 if (size
< sizeof(magic_etc
))
334 cpu_caps
->magic_etc
= magic_etc
= le32_to_cpu(caps
.magic_etc
);
336 switch (magic_etc
& VFS_CAP_REVISION_MASK
) {
337 case VFS_CAP_REVISION_1
:
338 if (size
!= XATTR_CAPS_SZ_1
)
340 tocopy
= VFS_CAP_U32_1
;
342 case VFS_CAP_REVISION_2
:
343 if (size
!= XATTR_CAPS_SZ_2
)
345 tocopy
= VFS_CAP_U32_2
;
351 CAP_FOR_EACH_U32(i
) {
354 cpu_caps
->permitted
.cap
[i
] = le32_to_cpu(caps
.data
[i
].permitted
);
355 cpu_caps
->inheritable
.cap
[i
] = le32_to_cpu(caps
.data
[i
].inheritable
);
362 * Attempt to get the on-exec apply capability sets for an executable file from
363 * its xattrs and, if present, apply them to the proposed credentials being
364 * constructed by execve().
366 static int get_file_caps(struct linux_binprm
*bprm
, bool *effective
)
368 struct dentry
*dentry
;
370 struct cpu_vfs_cap_data vcaps
;
372 bprm_clear_caps(bprm
);
374 if (!file_caps_enabled
)
377 if (bprm
->file
->f_vfsmnt
->mnt_flags
& MNT_NOSUID
)
380 dentry
= dget(bprm
->file
->f_dentry
);
382 rc
= get_vfs_caps_from_disk(dentry
, &vcaps
);
385 printk(KERN_NOTICE
"%s: get_vfs_caps_from_disk returned %d for %s\n",
386 __func__
, rc
, bprm
->filename
);
387 else if (rc
== -ENODATA
)
392 rc
= bprm_caps_from_vfs_caps(&vcaps
, bprm
, effective
);
394 printk(KERN_NOTICE
"%s: cap_from_disk returned %d for %s\n",
395 __func__
, rc
, bprm
->filename
);
400 bprm_clear_caps(bprm
);
406 int cap_inode_need_killpriv(struct dentry
*dentry
)
411 int cap_inode_killpriv(struct dentry
*dentry
)
416 static inline int get_file_caps(struct linux_binprm
*bprm
, bool *effective
)
418 bprm_clear_caps(bprm
);
424 * Determine whether a exec'ing process's new permitted capabilities should be
425 * limited to just what it already has.
427 * This prevents processes that are being ptraced from gaining access to
428 * CAP_SETPCAP, unless the process they're tracing already has it, and the
429 * binary they're executing has filecaps that elevate it.
431 * Returns 1 if they should be limited, 0 if they are not.
433 static inline int cap_limit_ptraced_target(void)
435 #ifndef CONFIG_SECURITY_FILE_CAPABILITIES
436 if (capable(CAP_SETPCAP
))
443 * cap_bprm_set_creds - Set up the proposed credentials for execve().
444 * @bprm: The execution parameters, including the proposed creds
446 * Set up the proposed credentials for a new execution context being
447 * constructed by execve(). The proposed creds in @bprm->cred is altered,
448 * which won't take effect immediately. Returns 0 if successful, -ve on error.
450 int cap_bprm_set_creds(struct linux_binprm
*bprm
)
452 const struct cred
*old
= current_cred();
453 struct cred
*new = bprm
->cred
;
458 ret
= get_file_caps(bprm
, &effective
);
462 if (!issecure(SECURE_NOROOT
)) {
464 * To support inheritance of root-permissions and suid-root
465 * executables under compatibility mode, we override the
466 * capability sets for the file.
468 * If only the real uid is 0, we do not set the effective bit.
470 if (new->euid
== 0 || new->uid
== 0) {
471 /* pP' = (cap_bset & ~0) | (pI & ~0) */
472 new->cap_permitted
= cap_combine(old
->cap_bset
,
473 old
->cap_inheritable
);
479 /* Don't let someone trace a set[ug]id/setpcap binary with the revised
480 * credentials unless they have the appropriate permit
482 if ((new->euid
!= old
->uid
||
483 new->egid
!= old
->gid
||
484 !cap_issubset(new->cap_permitted
, old
->cap_permitted
)) &&
485 bprm
->unsafe
& ~LSM_UNSAFE_PTRACE_CAP
) {
486 /* downgrade; they get no more than they had, and maybe less */
487 if (!capable(CAP_SETUID
)) {
488 new->euid
= new->uid
;
489 new->egid
= new->gid
;
491 if (cap_limit_ptraced_target())
492 new->cap_permitted
= cap_intersect(new->cap_permitted
,
496 new->suid
= new->fsuid
= new->euid
;
497 new->sgid
= new->fsgid
= new->egid
;
499 /* For init, we want to retain the capabilities set in the initial
500 * task. Thus we skip the usual capability rules
502 if (!is_global_init(current
)) {
504 new->cap_effective
= new->cap_permitted
;
506 cap_clear(new->cap_effective
);
508 bprm
->cap_effective
= effective
;
511 * Audit candidate if current->cap_effective is set
513 * We do not bother to audit if 3 things are true:
514 * 1) cap_effective has all caps
516 * 3) root is supposed to have all caps (SECURE_NOROOT)
517 * Since this is just a normal root execing a process.
519 * Number 1 above might fail if you don't have a full bset, but I think
520 * that is interesting information to audit.
522 if (!cap_isclear(new->cap_effective
)) {
523 if (!cap_issubset(CAP_FULL_SET
, new->cap_effective
) ||
524 new->euid
!= 0 || new->uid
!= 0 ||
525 issecure(SECURE_NOROOT
)) {
526 ret
= audit_log_bprm_fcaps(bprm
, new, old
);
532 new->securebits
&= ~issecure_mask(SECURE_KEEP_CAPS
);
537 * cap_bprm_secureexec - Determine whether a secure execution is required
538 * @bprm: The execution parameters
540 * Determine whether a secure execution is required, return 1 if it is, and 0
543 * The credentials have been committed by this point, and so are no longer
544 * available through @bprm->cred.
546 int cap_bprm_secureexec(struct linux_binprm
*bprm
)
548 const struct cred
*cred
= current_cred();
550 if (cred
->uid
!= 0) {
551 if (bprm
->cap_effective
)
553 if (!cap_isclear(cred
->cap_permitted
))
557 return (cred
->euid
!= cred
->uid
||
558 cred
->egid
!= cred
->gid
);
562 * cap_inode_setxattr - Determine whether an xattr may be altered
563 * @dentry: The inode/dentry being altered
564 * @name: The name of the xattr to be changed
565 * @value: The value that the xattr will be changed to
566 * @size: The size of value
567 * @flags: The replacement flag
569 * Determine whether an xattr may be altered or set on an inode, returning 0 if
570 * permission is granted, -ve if denied.
572 * This is used to make sure security xattrs don't get updated or set by those
573 * who aren't privileged to do so.
575 int cap_inode_setxattr(struct dentry
*dentry
, const char *name
,
576 const void *value
, size_t size
, int flags
)
578 if (!strcmp(name
, XATTR_NAME_CAPS
)) {
579 if (!capable(CAP_SETFCAP
))
584 if (!strncmp(name
, XATTR_SECURITY_PREFIX
,
585 sizeof(XATTR_SECURITY_PREFIX
) - 1) &&
586 !capable(CAP_SYS_ADMIN
))
592 * cap_inode_removexattr - Determine whether an xattr may be removed
593 * @dentry: The inode/dentry being altered
594 * @name: The name of the xattr to be changed
596 * Determine whether an xattr may be removed from an inode, returning 0 if
597 * permission is granted, -ve if denied.
599 * This is used to make sure security xattrs don't get removed by those who
600 * aren't privileged to remove them.
602 int cap_inode_removexattr(struct dentry
*dentry
, const char *name
)
604 if (!strcmp(name
, XATTR_NAME_CAPS
)) {
605 if (!capable(CAP_SETFCAP
))
610 if (!strncmp(name
, XATTR_SECURITY_PREFIX
,
611 sizeof(XATTR_SECURITY_PREFIX
) - 1) &&
612 !capable(CAP_SYS_ADMIN
))
618 * cap_emulate_setxuid() fixes the effective / permitted capabilities of
619 * a process after a call to setuid, setreuid, or setresuid.
621 * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of
622 * {r,e,s}uid != 0, the permitted and effective capabilities are
625 * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective
626 * capabilities of the process are cleared.
628 * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective
629 * capabilities are set to the permitted capabilities.
631 * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should
636 * cevans - New behaviour, Oct '99
637 * A process may, via prctl(), elect to keep its capabilities when it
638 * calls setuid() and switches away from uid==0. Both permitted and
639 * effective sets will be retained.
640 * Without this change, it was impossible for a daemon to drop only some
641 * of its privilege. The call to setuid(!=0) would drop all privileges!
642 * Keeping uid 0 is not an option because uid 0 owns too many vital
644 * Thanks to Olaf Kirch and Peter Benie for spotting this.
646 static inline void cap_emulate_setxuid(struct cred
*new, const struct cred
*old
)
648 if ((old
->uid
== 0 || old
->euid
== 0 || old
->suid
== 0) &&
649 (new->uid
!= 0 && new->euid
!= 0 && new->suid
!= 0) &&
650 !issecure(SECURE_KEEP_CAPS
)) {
651 cap_clear(new->cap_permitted
);
652 cap_clear(new->cap_effective
);
654 if (old
->euid
== 0 && new->euid
!= 0)
655 cap_clear(new->cap_effective
);
656 if (old
->euid
!= 0 && new->euid
== 0)
657 new->cap_effective
= new->cap_permitted
;
661 * cap_task_fix_setuid - Fix up the results of setuid() call
662 * @new: The proposed credentials
663 * @old: The current task's current credentials
664 * @flags: Indications of what has changed
666 * Fix up the results of setuid() call before the credential changes are
667 * actually applied, returning 0 to grant the changes, -ve to deny them.
669 int cap_task_fix_setuid(struct cred
*new, const struct cred
*old
, int flags
)
675 /* juggle the capabilities to follow [RES]UID changes unless
676 * otherwise suppressed */
677 if (!issecure(SECURE_NO_SETUID_FIXUP
))
678 cap_emulate_setxuid(new, old
);
682 /* juggle the capabilties to follow FSUID changes, unless
683 * otherwise suppressed
685 * FIXME - is fsuser used for all CAP_FS_MASK capabilities?
686 * if not, we might be a bit too harsh here.
688 if (!issecure(SECURE_NO_SETUID_FIXUP
)) {
689 if (old
->fsuid
== 0 && new->fsuid
!= 0)
691 cap_drop_fs_set(new->cap_effective
);
693 if (old
->fsuid
!= 0 && new->fsuid
== 0)
695 cap_raise_fs_set(new->cap_effective
,
707 #ifdef CONFIG_SECURITY_FILE_CAPABILITIES
709 * Rationale: code calling task_setscheduler, task_setioprio, and
710 * task_setnice, assumes that
711 * . if capable(cap_sys_nice), then those actions should be allowed
712 * . if not capable(cap_sys_nice), but acting on your own processes,
713 * then those actions should be allowed
714 * This is insufficient now since you can call code without suid, but
715 * yet with increased caps.
716 * So we check for increased caps on the target process.
718 static int cap_safe_nice(struct task_struct
*p
)
723 is_subset
= cap_issubset(__task_cred(p
)->cap_permitted
,
724 current_cred()->cap_permitted
);
727 if (!is_subset
&& !capable(CAP_SYS_NICE
))
733 * cap_task_setscheduler - Detemine if scheduler policy change is permitted
734 * @p: The task to affect
735 * @policy: The policy to effect
736 * @lp: The parameters to the scheduling policy
738 * Detemine if the requested scheduler policy change is permitted for the
739 * specified task, returning 0 if permission is granted, -ve if denied.
741 int cap_task_setscheduler(struct task_struct
*p
, int policy
,
742 struct sched_param
*lp
)
744 return cap_safe_nice(p
);
748 * cap_task_ioprio - Detemine if I/O priority change is permitted
749 * @p: The task to affect
750 * @ioprio: The I/O priority to set
752 * Detemine if the requested I/O priority change is permitted for the specified
753 * task, returning 0 if permission is granted, -ve if denied.
755 int cap_task_setioprio(struct task_struct
*p
, int ioprio
)
757 return cap_safe_nice(p
);
761 * cap_task_ioprio - Detemine if task priority change is permitted
762 * @p: The task to affect
763 * @nice: The nice value to set
765 * Detemine if the requested task priority change is permitted for the
766 * specified task, returning 0 if permission is granted, -ve if denied.
768 int cap_task_setnice(struct task_struct
*p
, int nice
)
770 return cap_safe_nice(p
);
774 * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from
775 * the current task's bounding set. Returns 0 on success, -ve on error.
777 static long cap_prctl_drop(struct cred
*new, unsigned long cap
)
779 if (!capable(CAP_SETPCAP
))
784 cap_lower(new->cap_bset
, cap
);
789 int cap_task_setscheduler (struct task_struct
*p
, int policy
,
790 struct sched_param
*lp
)
794 int cap_task_setioprio (struct task_struct
*p
, int ioprio
)
798 int cap_task_setnice (struct task_struct
*p
, int nice
)
805 * cap_task_prctl - Implement process control functions for this security module
806 * @option: The process control function requested
807 * @arg2, @arg3, @arg4, @arg5: The argument data for this function
809 * Allow process control functions (sys_prctl()) to alter capabilities; may
810 * also deny access to other functions not otherwise implemented here.
812 * Returns 0 or +ve on success, -ENOSYS if this function is not implemented
813 * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM
814 * modules will consider performing the function.
816 int cap_task_prctl(int option
, unsigned long arg2
, unsigned long arg3
,
817 unsigned long arg4
, unsigned long arg5
)
822 new = prepare_creds();
827 case PR_CAPBSET_READ
:
829 if (!cap_valid(arg2
))
831 error
= !!cap_raised(new->cap_bset
, arg2
);
834 #ifdef CONFIG_SECURITY_FILE_CAPABILITIES
835 case PR_CAPBSET_DROP
:
836 error
= cap_prctl_drop(new, arg2
);
842 * The next four prctl's remain to assist with transitioning a
843 * system from legacy UID=0 based privilege (when filesystem
844 * capabilities are not in use) to a system using filesystem
845 * capabilities only - as the POSIX.1e draft intended.
849 * PR_SET_SECUREBITS =
850 * issecure_mask(SECURE_KEEP_CAPS_LOCKED)
851 * | issecure_mask(SECURE_NOROOT)
852 * | issecure_mask(SECURE_NOROOT_LOCKED)
853 * | issecure_mask(SECURE_NO_SETUID_FIXUP)
854 * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED)
856 * will ensure that the current process and all of its
857 * children will be locked into a pure
858 * capability-based-privilege environment.
860 case PR_SET_SECUREBITS
:
862 if ((((new->securebits
& SECURE_ALL_LOCKS
) >> 1)
863 & (new->securebits
^ arg2
)) /*[1]*/
864 || ((new->securebits
& SECURE_ALL_LOCKS
& ~arg2
)) /*[2]*/
865 || (arg2
& ~(SECURE_ALL_LOCKS
| SECURE_ALL_BITS
)) /*[3]*/
866 || (cap_capable(current
, CAP_SETPCAP
, SECURITY_CAP_AUDIT
) != 0) /*[4]*/
868 * [1] no changing of bits that are locked
869 * [2] no unlocking of locks
870 * [3] no setting of unsupported bits
871 * [4] doing anything requires privilege (go read about
872 * the "sendmail capabilities bug")
875 /* cannot change a locked bit */
877 new->securebits
= arg2
;
880 case PR_GET_SECUREBITS
:
881 error
= new->securebits
;
884 #endif /* def CONFIG_SECURITY_FILE_CAPABILITIES */
886 case PR_GET_KEEPCAPS
:
887 if (issecure(SECURE_KEEP_CAPS
))
891 case PR_SET_KEEPCAPS
:
893 if (arg2
> 1) /* Note, we rely on arg2 being unsigned here */
896 if (issecure(SECURE_KEEP_CAPS_LOCKED
))
899 new->securebits
|= issecure_mask(SECURE_KEEP_CAPS
);
901 new->securebits
&= ~issecure_mask(SECURE_KEEP_CAPS
);
905 /* No functionality available - continue with default */
910 /* Functionality provided */
912 return commit_creds(new);
922 * cap_syslog - Determine whether syslog function is permitted
923 * @type: Function requested
925 * Determine whether the current process is permitted to use a particular
926 * syslog function, returning 0 if permission is granted, -ve if not.
928 int cap_syslog(int type
)
930 if ((type
!= 3 && type
!= 10) && !capable(CAP_SYS_ADMIN
))
936 * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted
937 * @mm: The VM space in which the new mapping is to be made
938 * @pages: The size of the mapping
940 * Determine whether the allocation of a new virtual mapping by the current
941 * task is permitted, returning 0 if permission is granted, -ve if not.
943 int cap_vm_enough_memory(struct mm_struct
*mm
, long pages
)
945 int cap_sys_admin
= 0;
947 if (cap_capable(current
, CAP_SYS_ADMIN
, SECURITY_CAP_NOAUDIT
) == 0)
949 return __vm_enough_memory(mm
, pages
, cap_sys_admin
);