Do not send ClientGUID on SMB2.02 dialect

ClientGUID must be zero for SMB2.02 dialect.  See section 2.2.3
of MS-SMB2. For SMB2.1 and later it must be non-zero.

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Sachin Prabhu <sprabhu@redhat.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index dc44610fdc0d..0feb743894b8 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -375,7 +375,12 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 
         req->Capabilities = cpu_to_le32(ses->server->vals->req_capabilities);
 
-        memcpy(req->ClientGUID, server->client_guid, SMB2_CLIENT_GUID_SIZE);
+        /* ClientGUID must be zero for SMB2.02 dialect */
+        if (ses->server->vals->protocol_id == SMB20_PROT_ID)
+                memset(req->ClientGUID, 0, SMB2_CLIENT_GUID_SIZE);
+        else
+                memcpy(req->ClientGUID, server->client_guid,
+                        SMB2_CLIENT_GUID_SIZE);
 
         iov[0].iov_base = (char *)req;
         /* 4 for rfc1002 length field */