diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 890b3a40c79ca5309feb1ff86ae66037fb7433fd..6d3e40d7029c47c6abd7264e8a8aa0cf526f4ee5 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1418,8 +1418,9 @@ CIFS_open(const unsigned int xid, struct cifs_open_parms *oparms, int *oplock,
 int
 cifs_discard_remaining_data(struct TCP_Server_Info *server)
 {
-	unsigned int rfclen = get_rfc1002_length(server->smallbuf);
-	int remaining = rfclen + 4 - server->total_read;
+	unsigned int rfclen = server->pdu_size;
+	int remaining = rfclen + server->vals->header_preamble_size -
+		server->total_read;
 
 	while (remaining > 0) {
 		int length;