keys: consider user namespace in key_permission
If a key is owned by another user namespace, then treat the
key as though it is owned by both another uid and gid.
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/keys/permission.c b/security/keys/permission.c
index 5d9fc7b..0ed802c 100644
--- a/security/keys/permission.c
+++ b/security/keys/permission.c
@@ -35,6 +35,9 @@
key = key_ref_to_ptr(key_ref);
+ if (key->user->user_ns != cred->user->user_ns)
+ goto use_other_perms;
+
/* use the second 8-bits of permissions for keys the caller owns */
if (key->uid == cred->fsuid) {
kperm = key->perm >> 16;
@@ -56,6 +59,8 @@
}
}
+use_other_perms:
+
/* otherwise use the least-significant 8-bits */
kperm = key->perm;