1 files changed, 7 insertions, 0 deletions

diff --git a/fs/xattr.c b/fs/xattr.c
index 4beafc43daa5..c243905835ab 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -38,6 +38,13 @@ xattr_permission(struct inode *inode, const char *name, int mask)
         if (mask & MAY_WRITE) {
                 if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
                         return -EPERM;
+                /*
+                 * Updating an xattr will likely cause i_uid and i_gid
+                 * to be writen back improperly if their true value is
+                 * unknown to the vfs.
+                 */
+                if (HAS_UNMAPPED_ID(inode))
+                        return -EPERM;
         }
 
         /*