[NFS]: Check that the server returns a valid regular file to our OPEN request

 Since it appears that some servers don't...

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index a6e251f..ac331d2 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -957,10 +957,12 @@
 				res = NULL;
 				goto out;
 			/* This turned out not to be a regular file */
+			case -EISDIR:
+			case -ENOTDIR:
+				goto no_open;
 			case -ELOOP:
 				if (!(nd->intent.open.flags & O_NOFOLLOW))
 					goto no_open;
-			/* case -EISDIR: */
 			/* case -EINVAL: */
 			default:
 				goto out;