diff options
| -rw-r--r-- | include/linux/capability.h | 13 | ||||
| -rw-r--r-- | include/linux/cred.h | 10 | ||||
| -rw-r--r-- | kernel/capability.c | 12 | ||||
| -rw-r--r-- | kernel/cred.c | 12 |
4 files changed, 27 insertions, 20 deletions
diff --git a/include/linux/capability.h b/include/linux/capability.h index 16ee8b4..d4675af 100644 --- a/include/linux/capability.h +++ b/include/linux/capability.h @@ -546,18 +546,7 @@ extern bool has_capability_noaudit(struct task_struct *t, int cap); extern bool capable(int cap); extern bool ns_capable(struct user_namespace *ns, int cap); extern bool task_ns_capable(struct task_struct *t, int cap); - -/** - * nsown_capable - Check superior capability to one's own user_ns - * @cap: The capability in question - * - * Return true if the current task has the given superior capability - * targeted at its own user namespace. - */ -static inline bool nsown_capable(int cap) -{ - return ns_capable(current_user_ns(), cap); -} +extern bool nsown_capable(int cap); /* audit system wants to get cap info from files as well */ extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps); diff --git a/include/linux/cred.h b/include/linux/cred.h index 9aeeb0b..be16b61 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -146,6 +146,7 @@ struct cred { void *security; /* subjective LSM security */ #endif struct user_struct *user; /* real user ID subscription */ + struct user_namespace *user_ns; /* cached user->user_ns */ struct group_info *group_info; /* supplementary groups for euid/fsgid */ struct rcu_head rcu; /* RCU deletion hook */ }; @@ -354,10 +355,15 @@ static inline void put_cred(const struct cred *_cred) #define current_fsgid() (current_cred_xxx(fsgid)) #define current_cap() (current_cred_xxx(cap_effective)) #define current_user() (current_cred_xxx(user)) -#define _current_user_ns() (current_cred_xxx(user)->user_ns) #define current_security() (current_cred_xxx(security)) -extern struct user_namespace *current_user_ns(void); +#ifdef CONFIG_USER_NS +#define current_user_ns() (current_cred_xxx(user_ns)) +#else +extern struct user_namespace init_user_ns; +#define current_user_ns() (&init_user_ns) +#endif + #define current_uid_gid(_uid, _gid) \ do { \ diff --git a/kernel/capability.c b/kernel/capability.c index bf0c734..32a80e0 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -399,3 +399,15 @@ bool task_ns_capable(struct task_struct *t, int cap) return ns_capable(task_cred_xxx(t, user)->user_ns, cap); } EXPORT_SYMBOL(task_ns_capable); + +/** + * nsown_capable - Check superior capability to one's own user_ns + * @cap: The capability in question + * + * Return true if the current task has the given superior capability + * targeted at its own user namespace. + */ +bool nsown_capable(int cap) +{ + return ns_capable(current_user_ns(), cap); +} diff --git a/kernel/cred.c b/kernel/cred.c index 5557b55..8093c16 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -54,6 +54,7 @@ struct cred init_cred = { .cap_effective = CAP_INIT_EFF_SET, .cap_bset = CAP_INIT_BSET, .user = INIT_USER, + .user_ns = &init_user_ns, .group_info = &init_groups, #ifdef CONFIG_KEYS .tgcred = &init_tgcred, @@ -410,6 +411,11 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags) goto error_put; } + /* cache user_ns in cred. Doesn't need a refcount because it will + * stay pinned by cred->user + */ + new->user_ns = new->user->user_ns; + #ifdef CONFIG_KEYS /* new threads get their own thread keyrings if their parent already * had one */ @@ -741,12 +747,6 @@ int set_create_files_as(struct cred *new, struct inode *inode) } EXPORT_SYMBOL(set_create_files_as); -struct user_namespace *current_user_ns(void) -{ - return _current_user_ns(); -} -EXPORT_SYMBOL(current_user_ns); - #ifdef CONFIG_DEBUG_CREDENTIALS bool creds_are_invalid(const struct cred *cred) |
