(namespace) Revert "UBUNTU: SAUCE: fs: Refuse uid/gid changes which don't map into s_user_ns"

BugLink: http://bugs.launchpad.net/bugs/1634964

This reverts commit fe50b8ac in
order to apply the upstream version of the same patch.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

fs/attr.c

@@ -79,17 +79,6 @@ int inode_change_ok(const struct inode *inode, struct iattr *attr)
 			return error;
 	}
 
-	/*
-	 * Verify that uid/gid changes are valid in the target namespace
-	 * of the superblock. This cannot be overriden using ATTR_FORCE.
-	 */
-	if (ia_valid & ATTR_UID &&
-	    from_kuid(inode->i_sb->s_user_ns, attr->ia_uid) == (uid_t)-1)
-		return -EOVERFLOW;
-	if (ia_valid & ATTR_GID &&
-	    from_kgid(inode->i_sb->s_user_ns, attr->ia_gid) == (gid_t)-1)
-		return -EOVERFLOW;
-
 	/* If force is set do it anyway. */
 	if (ia_valid & ATTR_FORCE)
 		return 0;