Commit | Line | Data |
---|---|---|
3e1c2515 | 1 | /* Common capabilities, needed by capability.o. |
1da177e4 LT |
2 | * |
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. | |
7 | * | |
8 | */ | |
9 | ||
c59ede7b | 10 | #include <linux/capability.h> |
3fc689e9 | 11 | #include <linux/audit.h> |
1da177e4 LT |
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> | |
17 | #include <linux/mm.h> | |
18 | #include <linux/mman.h> | |
19 | #include <linux/pagemap.h> | |
20 | #include <linux/swap.h> | |
1da177e4 LT |
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> | |
b5376771 | 26 | #include <linux/mount.h> |
b460cbc5 | 27 | #include <linux/sched.h> |
3898b1b4 AM |
28 | #include <linux/prctl.h> |
29 | #include <linux/securebits.h> | |
3486740a | 30 | #include <linux/user_namespace.h> |
40401530 | 31 | #include <linux/binfmts.h> |
51b79bee | 32 | #include <linux/personality.h> |
72c2d582 | 33 | |
b5f22a59 SH |
34 | /* |
35 | * If a non-root user executes a setuid-root binary in | |
36 | * !secure(SECURE_NOROOT) mode, then we raise capabilities. | |
37 | * However if fE is also set, then the intent is for only | |
38 | * the file capabilities to be applied, and the setuid-root | |
39 | * bit is left on either to change the uid (plausible) or | |
40 | * to get full privilege on a kernel without file capabilities | |
41 | * support. So in that case we do not raise capabilities. | |
42 | * | |
43 | * Warn if that happens, once per boot. | |
44 | */ | |
d7627467 | 45 | static void warn_setuid_and_fcaps_mixed(const char *fname) |
b5f22a59 SH |
46 | { |
47 | static int warned; | |
48 | if (!warned) { | |
49 | printk(KERN_INFO "warning: `%s' has both setuid-root and" | |
50 | " effective capabilities. Therefore not raising all" | |
51 | " capabilities.\n", fname); | |
52 | warned = 1; | |
53 | } | |
54 | } | |
55 | ||
1da177e4 LT |
56 | int cap_netlink_send(struct sock *sk, struct sk_buff *skb) |
57 | { | |
1da177e4 LT |
58 | return 0; |
59 | } | |
60 | ||
1d045980 DH |
61 | /** |
62 | * cap_capable - Determine whether a task has a particular effective capability | |
3699c53c | 63 | * @cred: The credentials to use |
3486740a | 64 | * @ns: The user namespace in which we need the capability |
1d045980 DH |
65 | * @cap: The capability to check for |
66 | * @audit: Whether to write an audit message or not | |
67 | * | |
68 | * Determine whether the nominated task has the specified capability amongst | |
69 | * its effective set, returning 0 if it does, -ve if it does not. | |
70 | * | |
3699c53c DH |
71 | * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable() |
72 | * and has_capability() functions. That is, it has the reverse semantics: | |
73 | * cap_has_capability() returns 0 when a task has a capability, but the | |
74 | * kernel's capable() and has_capability() returns 1 for this case. | |
a6dbb1ef | 75 | */ |
6a9de491 EP |
76 | int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, |
77 | int cap, int audit) | |
1da177e4 | 78 | { |
520d9eab | 79 | struct user_namespace *ns = targ_ns; |
3486740a | 80 | |
520d9eab EB |
81 | /* See if cred has the capability in the target user namespace |
82 | * by examining the target user namespace and all of the target | |
83 | * user namespace's parents. | |
84 | */ | |
85 | for (;;) { | |
3486740a | 86 | /* Do we have the necessary capabilities? */ |
520d9eab | 87 | if (ns == cred->user_ns) |
3486740a SH |
88 | return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; |
89 | ||
90 | /* Have we tried all of the parent namespaces? */ | |
520d9eab | 91 | if (ns == &init_user_ns) |
3486740a SH |
92 | return -EPERM; |
93 | ||
520d9eab EB |
94 | /* |
95 | * The owner of the user namespace in the parent of the | |
96 | * user namespace has all caps. | |
97 | */ | |
98 | if ((ns->parent == cred->user_ns) && uid_eq(ns->owner, cred->euid)) | |
99 | return 0; | |
100 | ||
3486740a | 101 | /* |
520d9eab | 102 | * If you have a capability in a parent user ns, then you have |
3486740a SH |
103 | * it over all children user namespaces as well. |
104 | */ | |
520d9eab | 105 | ns = ns->parent; |
3486740a SH |
106 | } |
107 | ||
108 | /* We never get here */ | |
1da177e4 LT |
109 | } |
110 | ||
1d045980 DH |
111 | /** |
112 | * cap_settime - Determine whether the current process may set the system clock | |
113 | * @ts: The time to set | |
114 | * @tz: The timezone to set | |
115 | * | |
116 | * Determine whether the current process may set the system clock and timezone | |
117 | * information, returning 0 if permission granted, -ve if denied. | |
118 | */ | |
1e6d7679 | 119 | int cap_settime(const struct timespec *ts, const struct timezone *tz) |
1da177e4 LT |
120 | { |
121 | if (!capable(CAP_SYS_TIME)) | |
122 | return -EPERM; | |
123 | return 0; | |
124 | } | |
125 | ||
1d045980 | 126 | /** |
9e48858f | 127 | * cap_ptrace_access_check - Determine whether the current process may access |
1d045980 DH |
128 | * another |
129 | * @child: The process to be accessed | |
130 | * @mode: The mode of attachment. | |
131 | * | |
8409cca7 SH |
132 | * If we are in the same or an ancestor user_ns and have all the target |
133 | * task's capabilities, then ptrace access is allowed. | |
134 | * If we have the ptrace capability to the target user_ns, then ptrace | |
135 | * access is allowed. | |
136 | * Else denied. | |
137 | * | |
1d045980 DH |
138 | * Determine whether a process may access another, returning 0 if permission |
139 | * granted, -ve if denied. | |
140 | */ | |
9e48858f | 141 | int cap_ptrace_access_check(struct task_struct *child, unsigned int mode) |
1da177e4 | 142 | { |
c69e8d9c | 143 | int ret = 0; |
8409cca7 | 144 | const struct cred *cred, *child_cred; |
414f6fbc | 145 | const kernel_cap_t *caller_caps; |
c69e8d9c DH |
146 | |
147 | rcu_read_lock(); | |
8409cca7 SH |
148 | cred = current_cred(); |
149 | child_cred = __task_cred(child); | |
414f6fbc JH |
150 | if (mode & PTRACE_MODE_FSCREDS) |
151 | caller_caps = &cred->cap_effective; | |
152 | else | |
153 | caller_caps = &cred->cap_permitted; | |
c4a4d603 | 154 | if (cred->user_ns == child_cred->user_ns && |
414f6fbc | 155 | cap_issubset(child_cred->cap_permitted, *caller_caps)) |
8409cca7 | 156 | goto out; |
c4a4d603 | 157 | if (ns_capable(child_cred->user_ns, CAP_SYS_PTRACE)) |
8409cca7 SH |
158 | goto out; |
159 | ret = -EPERM; | |
160 | out: | |
c69e8d9c DH |
161 | rcu_read_unlock(); |
162 | return ret; | |
5cd9c58f DH |
163 | } |
164 | ||
1d045980 DH |
165 | /** |
166 | * cap_ptrace_traceme - Determine whether another process may trace the current | |
167 | * @parent: The task proposed to be the tracer | |
168 | * | |
8409cca7 SH |
169 | * If parent is in the same or an ancestor user_ns and has all current's |
170 | * capabilities, then ptrace access is allowed. | |
171 | * If parent has the ptrace capability to current's user_ns, then ptrace | |
172 | * access is allowed. | |
173 | * Else denied. | |
174 | * | |
1d045980 DH |
175 | * Determine whether the nominated task is permitted to trace the current |
176 | * process, returning 0 if permission is granted, -ve if denied. | |
177 | */ | |
5cd9c58f DH |
178 | int cap_ptrace_traceme(struct task_struct *parent) |
179 | { | |
c69e8d9c | 180 | int ret = 0; |
8409cca7 | 181 | const struct cred *cred, *child_cred; |
c69e8d9c DH |
182 | |
183 | rcu_read_lock(); | |
8409cca7 SH |
184 | cred = __task_cred(parent); |
185 | child_cred = current_cred(); | |
c4a4d603 | 186 | if (cred->user_ns == child_cred->user_ns && |
8409cca7 SH |
187 | cap_issubset(child_cred->cap_permitted, cred->cap_permitted)) |
188 | goto out; | |
c4a4d603 | 189 | if (has_ns_capability(parent, child_cred->user_ns, CAP_SYS_PTRACE)) |
8409cca7 SH |
190 | goto out; |
191 | ret = -EPERM; | |
192 | out: | |
c69e8d9c DH |
193 | rcu_read_unlock(); |
194 | return ret; | |
1da177e4 LT |
195 | } |
196 | ||
1d045980 DH |
197 | /** |
198 | * cap_capget - Retrieve a task's capability sets | |
199 | * @target: The task from which to retrieve the capability sets | |
200 | * @effective: The place to record the effective set | |
201 | * @inheritable: The place to record the inheritable set | |
202 | * @permitted: The place to record the permitted set | |
203 | * | |
204 | * This function retrieves the capabilities of the nominated task and returns | |
205 | * them to the caller. | |
206 | */ | |
207 | int cap_capget(struct task_struct *target, kernel_cap_t *effective, | |
208 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1da177e4 | 209 | { |
c69e8d9c | 210 | const struct cred *cred; |
b6dff3ec | 211 | |
1da177e4 | 212 | /* Derived from kernel/capability.c:sys_capget. */ |
c69e8d9c DH |
213 | rcu_read_lock(); |
214 | cred = __task_cred(target); | |
b6dff3ec DH |
215 | *effective = cred->cap_effective; |
216 | *inheritable = cred->cap_inheritable; | |
217 | *permitted = cred->cap_permitted; | |
c69e8d9c | 218 | rcu_read_unlock(); |
1da177e4 LT |
219 | return 0; |
220 | } | |
221 | ||
1d045980 DH |
222 | /* |
223 | * Determine whether the inheritable capabilities are limited to the old | |
224 | * permitted set. Returns 1 if they are limited, 0 if they are not. | |
225 | */ | |
72c2d582 AM |
226 | static inline int cap_inh_is_capped(void) |
227 | { | |
72c2d582 | 228 | |
1d045980 DH |
229 | /* they are so limited unless the current task has the CAP_SETPCAP |
230 | * capability | |
231 | */ | |
c4a4d603 | 232 | if (cap_capable(current_cred(), current_cred()->user_ns, |
6a9de491 | 233 | CAP_SETPCAP, SECURITY_CAP_AUDIT) == 0) |
1d045980 | 234 | return 0; |
1d045980 | 235 | return 1; |
1209726c | 236 | } |
72c2d582 | 237 | |
1d045980 DH |
238 | /** |
239 | * cap_capset - Validate and apply proposed changes to current's capabilities | |
240 | * @new: The proposed new credentials; alterations should be made here | |
241 | * @old: The current task's current credentials | |
242 | * @effective: A pointer to the proposed new effective capabilities set | |
243 | * @inheritable: A pointer to the proposed new inheritable capabilities set | |
244 | * @permitted: A pointer to the proposed new permitted capabilities set | |
245 | * | |
246 | * This function validates and applies a proposed mass change to the current | |
247 | * process's capability sets. The changes are made to the proposed new | |
248 | * credentials, and assuming no error, will be committed by the caller of LSM. | |
249 | */ | |
d84f4f99 DH |
250 | int cap_capset(struct cred *new, |
251 | const struct cred *old, | |
252 | const kernel_cap_t *effective, | |
253 | const kernel_cap_t *inheritable, | |
254 | const kernel_cap_t *permitted) | |
1da177e4 | 255 | { |
d84f4f99 DH |
256 | if (cap_inh_is_capped() && |
257 | !cap_issubset(*inheritable, | |
258 | cap_combine(old->cap_inheritable, | |
259 | old->cap_permitted))) | |
72c2d582 | 260 | /* incapable of using this inheritable set */ |
1da177e4 | 261 | return -EPERM; |
d84f4f99 | 262 | |
3b7391de | 263 | if (!cap_issubset(*inheritable, |
d84f4f99 DH |
264 | cap_combine(old->cap_inheritable, |
265 | old->cap_bset))) | |
3b7391de SH |
266 | /* no new pI capabilities outside bounding set */ |
267 | return -EPERM; | |
1da177e4 LT |
268 | |
269 | /* verify restrictions on target's new Permitted set */ | |
d84f4f99 | 270 | if (!cap_issubset(*permitted, old->cap_permitted)) |
1da177e4 | 271 | return -EPERM; |
1da177e4 LT |
272 | |
273 | /* verify the _new_Effective_ is a subset of the _new_Permitted_ */ | |
d84f4f99 | 274 | if (!cap_issubset(*effective, *permitted)) |
1da177e4 | 275 | return -EPERM; |
1da177e4 | 276 | |
d84f4f99 DH |
277 | new->cap_effective = *effective; |
278 | new->cap_inheritable = *inheritable; | |
279 | new->cap_permitted = *permitted; | |
1da177e4 LT |
280 | return 0; |
281 | } | |
282 | ||
1d045980 DH |
283 | /* |
284 | * Clear proposed capability sets for execve(). | |
285 | */ | |
b5376771 SH |
286 | static inline void bprm_clear_caps(struct linux_binprm *bprm) |
287 | { | |
a6f76f23 | 288 | cap_clear(bprm->cred->cap_permitted); |
b5376771 SH |
289 | bprm->cap_effective = false; |
290 | } | |
291 | ||
1d045980 DH |
292 | /** |
293 | * cap_inode_need_killpriv - Determine if inode change affects privileges | |
294 | * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV | |
295 | * | |
296 | * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV | |
297 | * affects the security markings on that inode, and if it is, should | |
298 | * inode_killpriv() be invoked or the change rejected? | |
299 | * | |
300 | * Returns 0 if granted; +ve if granted, but inode_killpriv() is required; and | |
301 | * -ve to deny the change. | |
302 | */ | |
b5376771 SH |
303 | int cap_inode_need_killpriv(struct dentry *dentry) |
304 | { | |
305 | struct inode *inode = dentry->d_inode; | |
306 | int error; | |
307 | ||
acfa4380 | 308 | if (!inode->i_op->getxattr) |
b5376771 SH |
309 | return 0; |
310 | ||
311 | error = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0); | |
312 | if (error <= 0) | |
313 | return 0; | |
314 | return 1; | |
315 | } | |
316 | ||
1d045980 DH |
317 | /** |
318 | * cap_inode_killpriv - Erase the security markings on an inode | |
319 | * @dentry: The inode/dentry to alter | |
320 | * | |
321 | * Erase the privilege-enhancing security markings on an inode. | |
322 | * | |
323 | * Returns 0 if successful, -ve on error. | |
324 | */ | |
b5376771 SH |
325 | int cap_inode_killpriv(struct dentry *dentry) |
326 | { | |
327 | struct inode *inode = dentry->d_inode; | |
328 | ||
acfa4380 | 329 | if (!inode->i_op->removexattr) |
b5376771 SH |
330 | return 0; |
331 | ||
332 | return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS); | |
333 | } | |
334 | ||
1d045980 DH |
335 | /* |
336 | * Calculate the new process capability sets from the capability sets attached | |
337 | * to a file. | |
338 | */ | |
c0b00441 | 339 | static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps, |
a6f76f23 | 340 | struct linux_binprm *bprm, |
4d49f671 ZL |
341 | bool *effective, |
342 | bool *has_cap) | |
b5376771 | 343 | { |
a6f76f23 | 344 | struct cred *new = bprm->cred; |
c0b00441 EP |
345 | unsigned i; |
346 | int ret = 0; | |
347 | ||
348 | if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE) | |
a6f76f23 | 349 | *effective = true; |
c0b00441 | 350 | |
4d49f671 ZL |
351 | if (caps->magic_etc & VFS_CAP_REVISION_MASK) |
352 | *has_cap = true; | |
353 | ||
c0b00441 EP |
354 | CAP_FOR_EACH_U32(i) { |
355 | __u32 permitted = caps->permitted.cap[i]; | |
356 | __u32 inheritable = caps->inheritable.cap[i]; | |
357 | ||
358 | /* | |
359 | * pP' = (X & fP) | (pI & fI) | |
360 | */ | |
a6f76f23 DH |
361 | new->cap_permitted.cap[i] = |
362 | (new->cap_bset.cap[i] & permitted) | | |
363 | (new->cap_inheritable.cap[i] & inheritable); | |
c0b00441 | 364 | |
a6f76f23 DH |
365 | if (permitted & ~new->cap_permitted.cap[i]) |
366 | /* insufficient to execute correctly */ | |
c0b00441 | 367 | ret = -EPERM; |
c0b00441 EP |
368 | } |
369 | ||
370 | /* | |
371 | * For legacy apps, with no internal support for recognizing they | |
372 | * do not have enough capabilities, we return an error if they are | |
373 | * missing some "forced" (aka file-permitted) capabilities. | |
374 | */ | |
a6f76f23 | 375 | return *effective ? ret : 0; |
c0b00441 EP |
376 | } |
377 | ||
1d045980 DH |
378 | /* |
379 | * Extract the on-exec-apply capability sets for an executable file. | |
380 | */ | |
c0b00441 EP |
381 | int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps) |
382 | { | |
383 | struct inode *inode = dentry->d_inode; | |
b5376771 | 384 | __u32 magic_etc; |
e338d263 | 385 | unsigned tocopy, i; |
c0b00441 EP |
386 | int size; |
387 | struct vfs_cap_data caps; | |
388 | ||
389 | memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data)); | |
390 | ||
acfa4380 | 391 | if (!inode || !inode->i_op->getxattr) |
c0b00441 EP |
392 | return -ENODATA; |
393 | ||
394 | size = inode->i_op->getxattr((struct dentry *)dentry, XATTR_NAME_CAPS, &caps, | |
395 | XATTR_CAPS_SZ); | |
a6f76f23 | 396 | if (size == -ENODATA || size == -EOPNOTSUPP) |
c0b00441 EP |
397 | /* no data, that's ok */ |
398 | return -ENODATA; | |
c0b00441 EP |
399 | if (size < 0) |
400 | return size; | |
b5376771 | 401 | |
e338d263 | 402 | if (size < sizeof(magic_etc)) |
b5376771 SH |
403 | return -EINVAL; |
404 | ||
c0b00441 | 405 | cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps.magic_etc); |
b5376771 | 406 | |
a6f76f23 | 407 | switch (magic_etc & VFS_CAP_REVISION_MASK) { |
e338d263 AM |
408 | case VFS_CAP_REVISION_1: |
409 | if (size != XATTR_CAPS_SZ_1) | |
410 | return -EINVAL; | |
411 | tocopy = VFS_CAP_U32_1; | |
412 | break; | |
413 | case VFS_CAP_REVISION_2: | |
414 | if (size != XATTR_CAPS_SZ_2) | |
415 | return -EINVAL; | |
416 | tocopy = VFS_CAP_U32_2; | |
417 | break; | |
b5376771 SH |
418 | default: |
419 | return -EINVAL; | |
420 | } | |
e338d263 | 421 | |
5459c164 | 422 | CAP_FOR_EACH_U32(i) { |
c0b00441 EP |
423 | if (i >= tocopy) |
424 | break; | |
425 | cpu_caps->permitted.cap[i] = le32_to_cpu(caps.data[i].permitted); | |
426 | cpu_caps->inheritable.cap[i] = le32_to_cpu(caps.data[i].inheritable); | |
e338d263 | 427 | } |
a6f76f23 | 428 | |
76f01555 EP |
429 | cpu_caps->permitted.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK; |
430 | cpu_caps->inheritable.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK; | |
431 | ||
c0b00441 | 432 | return 0; |
b5376771 SH |
433 | } |
434 | ||
1d045980 DH |
435 | /* |
436 | * Attempt to get the on-exec apply capability sets for an executable file from | |
437 | * its xattrs and, if present, apply them to the proposed credentials being | |
438 | * constructed by execve(). | |
439 | */ | |
4d49f671 | 440 | static int get_file_caps(struct linux_binprm *bprm, bool *effective, bool *has_cap) |
b5376771 SH |
441 | { |
442 | struct dentry *dentry; | |
443 | int rc = 0; | |
c0b00441 | 444 | struct cpu_vfs_cap_data vcaps; |
b5376771 | 445 | |
3318a386 SH |
446 | bprm_clear_caps(bprm); |
447 | ||
1f29fae2 SH |
448 | if (!file_caps_enabled) |
449 | return 0; | |
450 | ||
182be684 | 451 | if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) |
b5376771 | 452 | return 0; |
b5376771 SH |
453 | |
454 | dentry = dget(bprm->file->f_dentry); | |
b5376771 | 455 | |
c0b00441 EP |
456 | rc = get_vfs_caps_from_disk(dentry, &vcaps); |
457 | if (rc < 0) { | |
458 | if (rc == -EINVAL) | |
459 | printk(KERN_NOTICE "%s: get_vfs_caps_from_disk returned %d for %s\n", | |
460 | __func__, rc, bprm->filename); | |
461 | else if (rc == -ENODATA) | |
462 | rc = 0; | |
b5376771 SH |
463 | goto out; |
464 | } | |
b5376771 | 465 | |
4d49f671 | 466 | rc = bprm_caps_from_vfs_caps(&vcaps, bprm, effective, has_cap); |
a6f76f23 DH |
467 | if (rc == -EINVAL) |
468 | printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n", | |
469 | __func__, rc, bprm->filename); | |
b5376771 SH |
470 | |
471 | out: | |
472 | dput(dentry); | |
473 | if (rc) | |
474 | bprm_clear_caps(bprm); | |
475 | ||
476 | return rc; | |
477 | } | |
478 | ||
1d045980 DH |
479 | /** |
480 | * cap_bprm_set_creds - Set up the proposed credentials for execve(). | |
481 | * @bprm: The execution parameters, including the proposed creds | |
482 | * | |
483 | * Set up the proposed credentials for a new execution context being | |
484 | * constructed by execve(). The proposed creds in @bprm->cred is altered, | |
485 | * which won't take effect immediately. Returns 0 if successful, -ve on error. | |
a6f76f23 DH |
486 | */ |
487 | int cap_bprm_set_creds(struct linux_binprm *bprm) | |
1da177e4 | 488 | { |
a6f76f23 DH |
489 | const struct cred *old = current_cred(); |
490 | struct cred *new = bprm->cred; | |
7d8db180 | 491 | bool effective, has_cap = false; |
b5376771 | 492 | int ret; |
18815a18 | 493 | kuid_t root_uid; |
1da177e4 | 494 | |
a6f76f23 | 495 | effective = false; |
4d49f671 | 496 | ret = get_file_caps(bprm, &effective, &has_cap); |
a6f76f23 DH |
497 | if (ret < 0) |
498 | return ret; | |
1da177e4 | 499 | |
18815a18 EB |
500 | root_uid = make_kuid(new->user_ns, 0); |
501 | ||
5459c164 | 502 | if (!issecure(SECURE_NOROOT)) { |
b5f22a59 SH |
503 | /* |
504 | * If the legacy file capability is set, then don't set privs | |
505 | * for a setuid root binary run by a non-root user. Do set it | |
506 | * for a root user just to cause least surprise to an admin. | |
507 | */ | |
18815a18 | 508 | if (has_cap && !uid_eq(new->uid, root_uid) && uid_eq(new->euid, root_uid)) { |
b5f22a59 SH |
509 | warn_setuid_and_fcaps_mixed(bprm->filename); |
510 | goto skip; | |
511 | } | |
5459c164 AM |
512 | /* |
513 | * To support inheritance of root-permissions and suid-root | |
514 | * executables under compatibility mode, we override the | |
515 | * capability sets for the file. | |
516 | * | |
a6f76f23 | 517 | * If only the real uid is 0, we do not set the effective bit. |
5459c164 | 518 | */ |
18815a18 | 519 | if (uid_eq(new->euid, root_uid) || uid_eq(new->uid, root_uid)) { |
5459c164 | 520 | /* pP' = (cap_bset & ~0) | (pI & ~0) */ |
a6f76f23 DH |
521 | new->cap_permitted = cap_combine(old->cap_bset, |
522 | old->cap_inheritable); | |
1da177e4 | 523 | } |
18815a18 | 524 | if (uid_eq(new->euid, root_uid)) |
a6f76f23 | 525 | effective = true; |
1da177e4 | 526 | } |
b5f22a59 | 527 | skip: |
b5376771 | 528 | |
d52fc5dd EP |
529 | /* if we have fs caps, clear dangerous personality flags */ |
530 | if (!cap_issubset(new->cap_permitted, old->cap_permitted)) | |
531 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
532 | ||
533 | ||
a6f76f23 | 534 | /* Don't let someone trace a set[ug]id/setpcap binary with the revised |
259e5e6c AL |
535 | * credentials unless they have the appropriate permit. |
536 | * | |
537 | * In addition, if NO_NEW_PRIVS, then ensure we get no new privs. | |
a6f76f23 | 538 | */ |
18815a18 EB |
539 | if ((!uid_eq(new->euid, old->uid) || |
540 | !gid_eq(new->egid, old->gid) || | |
a6f76f23 DH |
541 | !cap_issubset(new->cap_permitted, old->cap_permitted)) && |
542 | bprm->unsafe & ~LSM_UNSAFE_PTRACE_CAP) { | |
543 | /* downgrade; they get no more than they had, and maybe less */ | |
259e5e6c AL |
544 | if (!capable(CAP_SETUID) || |
545 | (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) { | |
a6f76f23 DH |
546 | new->euid = new->uid; |
547 | new->egid = new->gid; | |
1da177e4 | 548 | } |
b3a222e5 SH |
549 | new->cap_permitted = cap_intersect(new->cap_permitted, |
550 | old->cap_permitted); | |
1da177e4 LT |
551 | } |
552 | ||
a6f76f23 DH |
553 | new->suid = new->fsuid = new->euid; |
554 | new->sgid = new->fsgid = new->egid; | |
1da177e4 | 555 | |
4bf2ea77 EP |
556 | if (effective) |
557 | new->cap_effective = new->cap_permitted; | |
558 | else | |
559 | cap_clear(new->cap_effective); | |
a6f76f23 | 560 | bprm->cap_effective = effective; |
1da177e4 | 561 | |
3fc689e9 EP |
562 | /* |
563 | * Audit candidate if current->cap_effective is set | |
564 | * | |
565 | * We do not bother to audit if 3 things are true: | |
566 | * 1) cap_effective has all caps | |
567 | * 2) we are root | |
568 | * 3) root is supposed to have all caps (SECURE_NOROOT) | |
569 | * Since this is just a normal root execing a process. | |
570 | * | |
571 | * Number 1 above might fail if you don't have a full bset, but I think | |
572 | * that is interesting information to audit. | |
573 | */ | |
d84f4f99 DH |
574 | if (!cap_isclear(new->cap_effective)) { |
575 | if (!cap_issubset(CAP_FULL_SET, new->cap_effective) || | |
18815a18 | 576 | !uid_eq(new->euid, root_uid) || !uid_eq(new->uid, root_uid) || |
a6f76f23 DH |
577 | issecure(SECURE_NOROOT)) { |
578 | ret = audit_log_bprm_fcaps(bprm, new, old); | |
579 | if (ret < 0) | |
580 | return ret; | |
581 | } | |
3fc689e9 | 582 | } |
1da177e4 | 583 | |
d84f4f99 | 584 | new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS); |
a6f76f23 | 585 | return 0; |
1da177e4 LT |
586 | } |
587 | ||
1d045980 DH |
588 | /** |
589 | * cap_bprm_secureexec - Determine whether a secure execution is required | |
590 | * @bprm: The execution parameters | |
591 | * | |
592 | * Determine whether a secure execution is required, return 1 if it is, and 0 | |
593 | * if it is not. | |
594 | * | |
595 | * The credentials have been committed by this point, and so are no longer | |
596 | * available through @bprm->cred. | |
a6f76f23 DH |
597 | */ |
598 | int cap_bprm_secureexec(struct linux_binprm *bprm) | |
1da177e4 | 599 | { |
c69e8d9c | 600 | const struct cred *cred = current_cred(); |
18815a18 | 601 | kuid_t root_uid = make_kuid(cred->user_ns, 0); |
b6dff3ec | 602 | |
18815a18 | 603 | if (!uid_eq(cred->uid, root_uid)) { |
b5376771 SH |
604 | if (bprm->cap_effective) |
605 | return 1; | |
a6f76f23 | 606 | if (!cap_isclear(cred->cap_permitted)) |
b5376771 SH |
607 | return 1; |
608 | } | |
609 | ||
18815a18 EB |
610 | return (!uid_eq(cred->euid, cred->uid) || |
611 | !gid_eq(cred->egid, cred->gid)); | |
1da177e4 LT |
612 | } |
613 | ||
1d045980 DH |
614 | /** |
615 | * cap_inode_setxattr - Determine whether an xattr may be altered | |
616 | * @dentry: The inode/dentry being altered | |
617 | * @name: The name of the xattr to be changed | |
618 | * @value: The value that the xattr will be changed to | |
619 | * @size: The size of value | |
620 | * @flags: The replacement flag | |
621 | * | |
622 | * Determine whether an xattr may be altered or set on an inode, returning 0 if | |
623 | * permission is granted, -ve if denied. | |
624 | * | |
625 | * This is used to make sure security xattrs don't get updated or set by those | |
626 | * who aren't privileged to do so. | |
627 | */ | |
8f0cfa52 DH |
628 | int cap_inode_setxattr(struct dentry *dentry, const char *name, |
629 | const void *value, size_t size, int flags) | |
1da177e4 | 630 | { |
b5376771 SH |
631 | if (!strcmp(name, XATTR_NAME_CAPS)) { |
632 | if (!capable(CAP_SETFCAP)) | |
633 | return -EPERM; | |
634 | return 0; | |
1d045980 DH |
635 | } |
636 | ||
637 | if (!strncmp(name, XATTR_SECURITY_PREFIX, | |
c5b60b5e | 638 | sizeof(XATTR_SECURITY_PREFIX) - 1) && |
1da177e4 LT |
639 | !capable(CAP_SYS_ADMIN)) |
640 | return -EPERM; | |
641 | return 0; | |
642 | } | |
643 | ||
1d045980 DH |
644 | /** |
645 | * cap_inode_removexattr - Determine whether an xattr may be removed | |
646 | * @dentry: The inode/dentry being altered | |
647 | * @name: The name of the xattr to be changed | |
648 | * | |
649 | * Determine whether an xattr may be removed from an inode, returning 0 if | |
650 | * permission is granted, -ve if denied. | |
651 | * | |
652 | * This is used to make sure security xattrs don't get removed by those who | |
653 | * aren't privileged to remove them. | |
654 | */ | |
8f0cfa52 | 655 | int cap_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 656 | { |
b5376771 SH |
657 | if (!strcmp(name, XATTR_NAME_CAPS)) { |
658 | if (!capable(CAP_SETFCAP)) | |
659 | return -EPERM; | |
660 | return 0; | |
1d045980 DH |
661 | } |
662 | ||
663 | if (!strncmp(name, XATTR_SECURITY_PREFIX, | |
c5b60b5e | 664 | sizeof(XATTR_SECURITY_PREFIX) - 1) && |
1da177e4 LT |
665 | !capable(CAP_SYS_ADMIN)) |
666 | return -EPERM; | |
667 | return 0; | |
668 | } | |
669 | ||
a6f76f23 | 670 | /* |
1da177e4 LT |
671 | * cap_emulate_setxuid() fixes the effective / permitted capabilities of |
672 | * a process after a call to setuid, setreuid, or setresuid. | |
673 | * | |
674 | * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of | |
675 | * {r,e,s}uid != 0, the permitted and effective capabilities are | |
676 | * cleared. | |
677 | * | |
678 | * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective | |
679 | * capabilities of the process are cleared. | |
680 | * | |
681 | * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective | |
682 | * capabilities are set to the permitted capabilities. | |
683 | * | |
a6f76f23 | 684 | * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should |
1da177e4 LT |
685 | * never happen. |
686 | * | |
a6f76f23 | 687 | * -astor |
1da177e4 LT |
688 | * |
689 | * cevans - New behaviour, Oct '99 | |
690 | * A process may, via prctl(), elect to keep its capabilities when it | |
691 | * calls setuid() and switches away from uid==0. Both permitted and | |
692 | * effective sets will be retained. | |
693 | * Without this change, it was impossible for a daemon to drop only some | |
694 | * of its privilege. The call to setuid(!=0) would drop all privileges! | |
695 | * Keeping uid 0 is not an option because uid 0 owns too many vital | |
696 | * files.. | |
697 | * Thanks to Olaf Kirch and Peter Benie for spotting this. | |
698 | */ | |
d84f4f99 | 699 | static inline void cap_emulate_setxuid(struct cred *new, const struct cred *old) |
1da177e4 | 700 | { |
18815a18 EB |
701 | kuid_t root_uid = make_kuid(old->user_ns, 0); |
702 | ||
703 | if ((uid_eq(old->uid, root_uid) || | |
704 | uid_eq(old->euid, root_uid) || | |
705 | uid_eq(old->suid, root_uid)) && | |
706 | (!uid_eq(new->uid, root_uid) && | |
707 | !uid_eq(new->euid, root_uid) && | |
708 | !uid_eq(new->suid, root_uid)) && | |
3898b1b4 | 709 | !issecure(SECURE_KEEP_CAPS)) { |
d84f4f99 DH |
710 | cap_clear(new->cap_permitted); |
711 | cap_clear(new->cap_effective); | |
1da177e4 | 712 | } |
18815a18 | 713 | if (uid_eq(old->euid, root_uid) && !uid_eq(new->euid, root_uid)) |
d84f4f99 | 714 | cap_clear(new->cap_effective); |
18815a18 | 715 | if (!uid_eq(old->euid, root_uid) && uid_eq(new->euid, root_uid)) |
d84f4f99 | 716 | new->cap_effective = new->cap_permitted; |
1da177e4 LT |
717 | } |
718 | ||
1d045980 DH |
719 | /** |
720 | * cap_task_fix_setuid - Fix up the results of setuid() call | |
721 | * @new: The proposed credentials | |
722 | * @old: The current task's current credentials | |
723 | * @flags: Indications of what has changed | |
724 | * | |
725 | * Fix up the results of setuid() call before the credential changes are | |
726 | * actually applied, returning 0 to grant the changes, -ve to deny them. | |
727 | */ | |
d84f4f99 | 728 | int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags) |
1da177e4 LT |
729 | { |
730 | switch (flags) { | |
731 | case LSM_SETID_RE: | |
732 | case LSM_SETID_ID: | |
733 | case LSM_SETID_RES: | |
1d045980 DH |
734 | /* juggle the capabilities to follow [RES]UID changes unless |
735 | * otherwise suppressed */ | |
d84f4f99 DH |
736 | if (!issecure(SECURE_NO_SETUID_FIXUP)) |
737 | cap_emulate_setxuid(new, old); | |
1da177e4 | 738 | break; |
1da177e4 | 739 | |
1d045980 DH |
740 | case LSM_SETID_FS: |
741 | /* juggle the capabilties to follow FSUID changes, unless | |
742 | * otherwise suppressed | |
743 | * | |
d84f4f99 DH |
744 | * FIXME - is fsuser used for all CAP_FS_MASK capabilities? |
745 | * if not, we might be a bit too harsh here. | |
746 | */ | |
747 | if (!issecure(SECURE_NO_SETUID_FIXUP)) { | |
18815a18 EB |
748 | kuid_t root_uid = make_kuid(old->user_ns, 0); |
749 | if (uid_eq(old->fsuid, root_uid) && !uid_eq(new->fsuid, root_uid)) | |
d84f4f99 DH |
750 | new->cap_effective = |
751 | cap_drop_fs_set(new->cap_effective); | |
1d045980 | 752 | |
18815a18 | 753 | if (!uid_eq(old->fsuid, root_uid) && uid_eq(new->fsuid, root_uid)) |
d84f4f99 DH |
754 | new->cap_effective = |
755 | cap_raise_fs_set(new->cap_effective, | |
756 | new->cap_permitted); | |
1da177e4 | 757 | } |
d84f4f99 | 758 | break; |
1d045980 | 759 | |
1da177e4 LT |
760 | default: |
761 | return -EINVAL; | |
762 | } | |
763 | ||
764 | return 0; | |
765 | } | |
766 | ||
b5376771 SH |
767 | /* |
768 | * Rationale: code calling task_setscheduler, task_setioprio, and | |
769 | * task_setnice, assumes that | |
770 | * . if capable(cap_sys_nice), then those actions should be allowed | |
771 | * . if not capable(cap_sys_nice), but acting on your own processes, | |
772 | * then those actions should be allowed | |
773 | * This is insufficient now since you can call code without suid, but | |
774 | * yet with increased caps. | |
775 | * So we check for increased caps on the target process. | |
776 | */ | |
de45e806 | 777 | static int cap_safe_nice(struct task_struct *p) |
b5376771 | 778 | { |
c69e8d9c DH |
779 | int is_subset; |
780 | ||
781 | rcu_read_lock(); | |
782 | is_subset = cap_issubset(__task_cred(p)->cap_permitted, | |
783 | current_cred()->cap_permitted); | |
784 | rcu_read_unlock(); | |
785 | ||
786 | if (!is_subset && !capable(CAP_SYS_NICE)) | |
b5376771 SH |
787 | return -EPERM; |
788 | return 0; | |
789 | } | |
790 | ||
1d045980 DH |
791 | /** |
792 | * cap_task_setscheduler - Detemine if scheduler policy change is permitted | |
793 | * @p: The task to affect | |
1d045980 DH |
794 | * |
795 | * Detemine if the requested scheduler policy change is permitted for the | |
796 | * specified task, returning 0 if permission is granted, -ve if denied. | |
797 | */ | |
b0ae1981 | 798 | int cap_task_setscheduler(struct task_struct *p) |
b5376771 SH |
799 | { |
800 | return cap_safe_nice(p); | |
801 | } | |
802 | ||
1d045980 DH |
803 | /** |
804 | * cap_task_ioprio - Detemine if I/O priority change is permitted | |
805 | * @p: The task to affect | |
806 | * @ioprio: The I/O priority to set | |
807 | * | |
808 | * Detemine if the requested I/O priority change is permitted for the specified | |
809 | * task, returning 0 if permission is granted, -ve if denied. | |
810 | */ | |
811 | int cap_task_setioprio(struct task_struct *p, int ioprio) | |
b5376771 SH |
812 | { |
813 | return cap_safe_nice(p); | |
814 | } | |
815 | ||
1d045980 DH |
816 | /** |
817 | * cap_task_ioprio - Detemine if task priority change is permitted | |
818 | * @p: The task to affect | |
819 | * @nice: The nice value to set | |
820 | * | |
821 | * Detemine if the requested task priority change is permitted for the | |
822 | * specified task, returning 0 if permission is granted, -ve if denied. | |
823 | */ | |
824 | int cap_task_setnice(struct task_struct *p, int nice) | |
b5376771 SH |
825 | { |
826 | return cap_safe_nice(p); | |
827 | } | |
828 | ||
3b7391de | 829 | /* |
1d045980 DH |
830 | * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from |
831 | * the current task's bounding set. Returns 0 on success, -ve on error. | |
3b7391de | 832 | */ |
d84f4f99 | 833 | static long cap_prctl_drop(struct cred *new, unsigned long cap) |
3b7391de SH |
834 | { |
835 | if (!capable(CAP_SETPCAP)) | |
836 | return -EPERM; | |
837 | if (!cap_valid(cap)) | |
838 | return -EINVAL; | |
d84f4f99 DH |
839 | |
840 | cap_lower(new->cap_bset, cap); | |
3b7391de SH |
841 | return 0; |
842 | } | |
3898b1b4 | 843 | |
1d045980 DH |
844 | /** |
845 | * cap_task_prctl - Implement process control functions for this security module | |
846 | * @option: The process control function requested | |
847 | * @arg2, @arg3, @arg4, @arg5: The argument data for this function | |
848 | * | |
849 | * Allow process control functions (sys_prctl()) to alter capabilities; may | |
850 | * also deny access to other functions not otherwise implemented here. | |
851 | * | |
852 | * Returns 0 or +ve on success, -ENOSYS if this function is not implemented | |
853 | * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM | |
854 | * modules will consider performing the function. | |
855 | */ | |
3898b1b4 | 856 | int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, |
d84f4f99 | 857 | unsigned long arg4, unsigned long arg5) |
3898b1b4 | 858 | { |
d84f4f99 | 859 | struct cred *new; |
3898b1b4 AM |
860 | long error = 0; |
861 | ||
d84f4f99 DH |
862 | new = prepare_creds(); |
863 | if (!new) | |
864 | return -ENOMEM; | |
865 | ||
3898b1b4 AM |
866 | switch (option) { |
867 | case PR_CAPBSET_READ: | |
d84f4f99 | 868 | error = -EINVAL; |
3898b1b4 | 869 | if (!cap_valid(arg2)) |
d84f4f99 DH |
870 | goto error; |
871 | error = !!cap_raised(new->cap_bset, arg2); | |
872 | goto no_change; | |
873 | ||
3898b1b4 | 874 | case PR_CAPBSET_DROP: |
d84f4f99 DH |
875 | error = cap_prctl_drop(new, arg2); |
876 | if (error < 0) | |
877 | goto error; | |
878 | goto changed; | |
3898b1b4 AM |
879 | |
880 | /* | |
881 | * The next four prctl's remain to assist with transitioning a | |
882 | * system from legacy UID=0 based privilege (when filesystem | |
883 | * capabilities are not in use) to a system using filesystem | |
884 | * capabilities only - as the POSIX.1e draft intended. | |
885 | * | |
886 | * Note: | |
887 | * | |
888 | * PR_SET_SECUREBITS = | |
889 | * issecure_mask(SECURE_KEEP_CAPS_LOCKED) | |
890 | * | issecure_mask(SECURE_NOROOT) | |
891 | * | issecure_mask(SECURE_NOROOT_LOCKED) | |
892 | * | issecure_mask(SECURE_NO_SETUID_FIXUP) | |
893 | * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED) | |
894 | * | |
895 | * will ensure that the current process and all of its | |
896 | * children will be locked into a pure | |
897 | * capability-based-privilege environment. | |
898 | */ | |
899 | case PR_SET_SECUREBITS: | |
d84f4f99 DH |
900 | error = -EPERM; |
901 | if ((((new->securebits & SECURE_ALL_LOCKS) >> 1) | |
902 | & (new->securebits ^ arg2)) /*[1]*/ | |
903 | || ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/ | |
904 | || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/ | |
6a9de491 | 905 | || (cap_capable(current_cred(), |
c4a4d603 | 906 | current_cred()->user_ns, CAP_SETPCAP, |
3699c53c | 907 | SECURITY_CAP_AUDIT) != 0) /*[4]*/ |
3898b1b4 AM |
908 | /* |
909 | * [1] no changing of bits that are locked | |
910 | * [2] no unlocking of locks | |
911 | * [3] no setting of unsupported bits | |
912 | * [4] doing anything requires privilege (go read about | |
913 | * the "sendmail capabilities bug") | |
914 | */ | |
d84f4f99 DH |
915 | ) |
916 | /* cannot change a locked bit */ | |
917 | goto error; | |
918 | new->securebits = arg2; | |
919 | goto changed; | |
920 | ||
3898b1b4 | 921 | case PR_GET_SECUREBITS: |
d84f4f99 DH |
922 | error = new->securebits; |
923 | goto no_change; | |
3898b1b4 | 924 | |
3898b1b4 AM |
925 | case PR_GET_KEEPCAPS: |
926 | if (issecure(SECURE_KEEP_CAPS)) | |
927 | error = 1; | |
d84f4f99 DH |
928 | goto no_change; |
929 | ||
3898b1b4 | 930 | case PR_SET_KEEPCAPS: |
d84f4f99 | 931 | error = -EINVAL; |
3898b1b4 | 932 | if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */ |
d84f4f99 DH |
933 | goto error; |
934 | error = -EPERM; | |
935 | if (issecure(SECURE_KEEP_CAPS_LOCKED)) | |
936 | goto error; | |
937 | if (arg2) | |
938 | new->securebits |= issecure_mask(SECURE_KEEP_CAPS); | |
3898b1b4 | 939 | else |
d84f4f99 DH |
940 | new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS); |
941 | goto changed; | |
3898b1b4 AM |
942 | |
943 | default: | |
944 | /* No functionality available - continue with default */ | |
d84f4f99 DH |
945 | error = -ENOSYS; |
946 | goto error; | |
3898b1b4 AM |
947 | } |
948 | ||
949 | /* Functionality provided */ | |
d84f4f99 DH |
950 | changed: |
951 | return commit_creds(new); | |
952 | ||
953 | no_change: | |
d84f4f99 DH |
954 | error: |
955 | abort_creds(new); | |
956 | return error; | |
1da177e4 LT |
957 | } |
958 | ||
1d045980 DH |
959 | /** |
960 | * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted | |
961 | * @mm: The VM space in which the new mapping is to be made | |
962 | * @pages: The size of the mapping | |
963 | * | |
964 | * Determine whether the allocation of a new virtual mapping by the current | |
965 | * task is permitted, returning 0 if permission is granted, -ve if not. | |
966 | */ | |
34b4e4aa | 967 | int cap_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
968 | { |
969 | int cap_sys_admin = 0; | |
970 | ||
6a9de491 | 971 | if (cap_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN, |
3699c53c | 972 | SECURITY_CAP_NOAUDIT) == 0) |
1da177e4 | 973 | cap_sys_admin = 1; |
34b4e4aa | 974 | return __vm_enough_memory(mm, pages, cap_sys_admin); |
1da177e4 | 975 | } |
7c73875e EP |
976 | |
977 | /* | |
d007794a | 978 | * cap_mmap_addr - check if able to map given addr |
7c73875e | 979 | * @addr: address attempting to be mapped |
7c73875e | 980 | * |
6f262d8e | 981 | * If the process is attempting to map memory below dac_mmap_min_addr they need |
7c73875e EP |
982 | * CAP_SYS_RAWIO. The other parameters to this function are unused by the |
983 | * capability security module. Returns 0 if this mapping should be allowed | |
984 | * -EPERM if not. | |
985 | */ | |
d007794a | 986 | int cap_mmap_addr(unsigned long addr) |
7c73875e EP |
987 | { |
988 | int ret = 0; | |
989 | ||
a2551df7 | 990 | if (addr < dac_mmap_min_addr) { |
6a9de491 | 991 | ret = cap_capable(current_cred(), &init_user_ns, CAP_SYS_RAWIO, |
7c73875e EP |
992 | SECURITY_CAP_AUDIT); |
993 | /* set PF_SUPERPRIV if it turns out we allow the low mmap */ | |
994 | if (ret == 0) | |
995 | current->flags |= PF_SUPERPRIV; | |
996 | } | |
997 | return ret; | |
998 | } | |
d007794a | 999 | |
e5467859 AV |
1000 | int cap_mmap_file(struct file *file, unsigned long reqprot, |
1001 | unsigned long prot, unsigned long flags) | |
d007794a | 1002 | { |
e5467859 | 1003 | return 0; |
d007794a | 1004 | } |