userns: Implement sk_user_ns

Add a helper sk_user_ns to make it easy to find the user namespace of the process that opened a socket. Acked-by: David S. Miller <[email protected]> Acked-by: Serge Hallyn <[email protected]> Signed-off-by: Eric W. Biederman <[email protected]>
chewitt · Aug 15, 2012 · c336d14 · c336d14
1 parent 3fbc290
commit c336d14
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/include/net/sock.h b/include/net/sock.h
@@ -604,6 +604,15 @@ static inline void sk_add_bind_node(struct sock *sk,
 #define sk_for_each_bound(__sk, node, list) \
 	hlist_for_each_entry(__sk, node, list, sk_bind_node)
 
+static inline struct user_namespace *sk_user_ns(struct sock *sk)
+{
+	/* Careful only use this in a context where these parameters
+	 * can not change and must all be valid, such as recvmsg from
+	 * userspace.
+	 */
+	return sk->sk_socket->file->f_cred->user_ns;
+}
+
 /* Sock flags */
 enum sock_flags {
 	SOCK_DEAD,