1 // SPDX-License-Identifier: GPL-2.0
36  *   http://www.kernel.org/pub/linux/libs/security/linux-privs/
41 	char name[sizeof(current->comm)];  in warn_legacy_capability_use()
43 	pr_info_once("warning: `%s' uses 32-bit capabilities (legacy support in use)\n",  in warn_legacy_capability_use()
50  * the necessary user-space source code changes. As such, we have
65 	char name[sizeof(current->comm)];  in warn_deprecated_v2()
73  * array, or a negative value on error.
79 	if (get_user(version, &header->version))  in cap_validate_magic()
80 		return -EFAULT;  in cap_validate_magic()
94 		if (put_user((u32)_KERNEL_CAPABILITY_VERSION, &header->version))  in cap_validate_magic()
95 			return -EFAULT;  in cap_validate_magic()
96 		return -EINVAL;  in cap_validate_magic()
104  * process is the current process. As such, we can't be in this code
105  * at the same time as we are in the process of setting capabilities
106  * in this process. The net result is that we can limit our use of
107  * locks to when we are reading the caps of another process.
121 			ret = -ESRCH;  in cap_get_target_pid()
133  * sys_capget - get the capabilities of a given process.
139  * Returns 0 on success and < 0 on error.
151 		return ((dataptr == NULL) && (ret == -EINVAL)) ? 0 : ret;  in SYSCALL_DEFINE2()
153 	if (get_user(pid, &header->pid))  in SYSCALL_DEFINE2()
154 		return -EFAULT;  in SYSCALL_DEFINE2()
157 		return -EINVAL;  in SYSCALL_DEFINE2()
164 	 * Annoying legacy format with 64-bit capabilities exposed  in SYSCALL_DEFINE2()
165 	 * as two sets of 32-bit fields, so we need to split the  in SYSCALL_DEFINE2()
174 	 * we silently drop the upper capabilities here. This  in SYSCALL_DEFINE2()
180 	 * This behavior is considered fail-safe  in SYSCALL_DEFINE2()
186 	 * (-ERANGE), but that causes legacy applications to  in SYSCALL_DEFINE2()
192 		return -EFAULT;  in SYSCALL_DEFINE2()
203  * sys_capset - set capabilities for a process or (*) a group of processes
212  * The restrictions on setting capabilities are specified as:
218  * Returns 0 on success and < 0 on error.
233 	if (get_user(pid, &header->pid))  in SYSCALL_DEFINE2()
234 		return -EFAULT;  in SYSCALL_DEFINE2()
238 		return -EPERM;  in SYSCALL_DEFINE2()
242 		return -EFAULT;  in SYSCALL_DEFINE2()
245 		return -EFAULT;  in SYSCALL_DEFINE2()
253 		return -ENOMEM;  in SYSCALL_DEFINE2()
270  * has_ns_capability - Does a task have a capability in a specific user ns
272  * @ns: target user namespace
278  * Note that this does not set PF_SUPERPRIV on the task.
281 		       struct user_namespace *ns, int cap)  in has_ns_capability()  argument
286 	ret = security_capable(__task_cred(t), ns, cap, CAP_OPT_NONE);  in has_ns_capability()
293  * has_capability - Does a task have a capability in init_user_ns
300  * Note that this does not set PF_SUPERPRIV on the task.
309  * has_ns_capability_noaudit - Does a task have a capability (unaudited)
310  * in a specific user ns.
312  * @ns: target user namespace
319  * Note that this does not set PF_SUPERPRIV on the task.
322 			       struct user_namespace *ns, int cap)  in has_ns_capability_noaudit()  argument
327 	ret = security_capable(__task_cred(t), ns, cap, CAP_OPT_NOAUDIT);  in has_ns_capability_noaudit()
334  * has_capability_noaudit - Does a task have a capability (unaudited) in the
335  * initial user ns
343  * Note that this does not set PF_SUPERPRIV on the task.
351 static bool ns_capable_common(struct user_namespace *ns,  in ns_capable_common()  argument
362 	capable = security_capable(current_cred(), ns, cap, opts);  in ns_capable_common()
364 		current->flags |= PF_SUPERPRIV;  in ns_capable_common()
371  * ns_capable - Determine if the current task has a superior capability in effect
372  * @ns:  The usernamespace we want the capability in
378  * This sets PF_SUPERPRIV on the task if the capability is available on the
381 bool ns_capable(struct user_namespace *ns, int cap)  in ns_capable()  argument
383 	return ns_capable_common(ns, cap, CAP_OPT_NONE);  in ns_capable()
388  * ns_capable_noaudit - Determine if the current task has a superior capability
390  * @ns:  The usernamespace we want the capability in
396  * This sets PF_SUPERPRIV on the task if the capability is available on the
399 bool ns_capable_noaudit(struct user_namespace *ns, int cap)  in ns_capable_noaudit()  argument
401 	return ns_capable_common(ns, cap, CAP_OPT_NOAUDIT);  in ns_capable_noaudit()
406  * ns_capable_setid - Determine if the current task has a superior capability
409  * @ns:  The usernamespace we want the capability in
415  * This sets PF_SUPERPRIV on the task if the capability is available on the
418 bool ns_capable_setid(struct user_namespace *ns, int cap)  in ns_capable_setid()  argument
420 	return ns_capable_common(ns, cap, CAP_OPT_INSETID);  in ns_capable_setid()
425  * capable - Determine if the current task has a superior capability in effect
431  * This sets PF_SUPERPRIV on the task if the capability is available on the
442  * file_ns_capable - Determine if the file's opener had a capability in effect
443  * @file:  The file we want to check
444  * @ns:  The usernamespace we want the capability in
453 bool file_ns_capable(const struct file *file, struct user_namespace *ns,  in file_ns_capable()  argument
460 	if (security_capable(file->f_cred, ns, cap, CAP_OPT_NONE) == 0)  in file_ns_capable()
468  * privileged_wrt_inode_uidgid - Do capabilities in the namespace work over the inode?
469  * @ns: The user namespace in question
475 bool privileged_wrt_inode_uidgid(struct user_namespace *ns,  in privileged_wrt_inode_uidgid()  argument
479 	return vfsuid_has_mapping(ns, i_uid_into_vfsuid(idmap, inode)) &&  in privileged_wrt_inode_uidgid()
480 	       vfsgid_has_mapping(ns, i_gid_into_vfsgid(idmap, inode));  in privileged_wrt_inode_uidgid()
484  * capable_wrt_inode_uidgid - Check nsown_capable and uid and gid mapped
496 	struct user_namespace *ns = current_user_ns();  in capable_wrt_inode_uidgid()  local
498 	return ns_capable(ns, cap) &&  in capable_wrt_inode_uidgid()
499 	       privileged_wrt_inode_uidgid(ns, idmap, inode);  in capable_wrt_inode_uidgid()
504  * ptracer_capable - Determine if the ptracer holds CAP_SYS_PTRACE in the namespace
506  * @ns: The user namespace to search for CAP_SYS_PTRACE in
511 bool ptracer_capable(struct task_struct *tsk, struct user_namespace *ns)  in ptracer_capable()  argument
517 	cred = rcu_dereference(tsk->ptracer_cred);  in ptracer_capable()
519 		ret = security_capable(cred, ns, CAP_SYS_PTRACE,  in ptracer_capable()