commit 07108d0e7c7fbbf9c6d76c0af2f1813e4f3f0800
author Steve French <stfrench@microsoft.com> Sun Apr 01 20:15:55 2018 -0500
committer Steve French <smfrench@gmail.com> Mon Apr 02 13:11:15 2018 -0500
tree dc01c076ce918a4c8c4ef51035932dd8313caa8f
parent 7ea884c77e5c97f1e0a1a422d961d27f78ca2745

cifs: Add minor debug message during negprot

Check for unknown security mode flags during negotiate protocol
if debugging enabled.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

fs/cifs/smb2pdu.c

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 0e04b57..f7741ce 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -584,8 +584,10 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 			       SMB2_MAX_BUFFER_SIZE);
 	server->max_read = le32_to_cpu(rsp->MaxReadSize);
 	server->max_write = le32_to_cpu(rsp->MaxWriteSize);
-	/* BB Do we need to validate the SecurityMode? */
 	server->sec_mode = le16_to_cpu(rsp->SecurityMode);
+	if ((server->sec_mode & SMB2_SEC_MODE_FLAGS_ALL) != server->sec_mode)
+		cifs_dbg(FYI, "Server returned unexpected security mode 0x%x\n",
+				server->sec_mode);
 	server->capabilities = le32_to_cpu(rsp->Capabilities);
 	/* Internal types */
 	server->capabilities |= SMB2_NT_FIND | SMB2_LARGE_FILES;