diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 8cd4b52..27c4f25 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -282,7 +282,7 @@
 	byte_count = be32_to_cpu(pTargetSMB->smb_buf_length);
 	byte_count += total_in_buf2;
 	/* don't allow buffer to overflow */
-	if (byte_count > CIFSMaxBufSize)
+	if (byte_count > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4)
 		return -ENOBUFS;
 	pTargetSMB->smb_buf_length = cpu_to_be32(byte_count);