diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2010-06-13 03:28:03 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-06-16 14:55:34 -0700 |
| commit | 5c1469de7545a35a16ff2b902e217044a7d2f8a5 (patch) | |
| tree | 2a3b48da4dab1516234633ee5e71766801210e49 /include | |
| parent | 812e876e842488221aa54cb4587a8a33445cfa9e (diff) | |
user_ns: Introduce user_nsmap_uid and user_ns_map_gid.
Define what happens when a we view a uid from one user_namespace
in another user_namepece.
- If the user namespaces are the same no mapping is necessary.
- For most cases of difference use overflowuid and overflowgid,
the uid and gid currently used for 16bit apis when we have a 32bit uid
that does fit in 16bits. Effectively the situation is the same,
we want to return a uid or gid that is not assigned to any user.
- For the case when we happen to be mapping the uid or gid of the
creator of the target user namespace use uid 0 and gid as confusing
that user with root is not a problem.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/user_namespace.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h index cc4f45361dbb..8178156711f9 100644 --- a/include/linux/user_namespace.h +++ b/include/linux/user_namespace.h @@ -36,6 +36,9 @@ static inline void put_user_ns(struct user_namespace *ns) kref_put(&ns->kref, free_user_ns); } +uid_t user_ns_map_uid(struct user_namespace *to, const struct cred *cred, uid_t uid); +gid_t user_ns_map_gid(struct user_namespace *to, const struct cred *cred, gid_t gid); + #else static inline struct user_namespace *get_user_ns(struct user_namespace *ns) @@ -52,6 +55,17 @@ static inline void put_user_ns(struct user_namespace *ns) { } +static inline uid_t user_ns_map_uid(struct user_namespace *to, + const struct cred *cred, uid_t uid) +{ + return uid; +} +static inline gid_t user_ns_map_gid(struct user_namespace *to, + const struct cred *cred, gid_t gid) +{ + return gid; +} + #endif #endif /* _LINUX_USER_H */ |