tree 51dec04ec8ecb1d29769868dc46348ff409fb03c
parent ee6858f72a39226728e5085fc7388785a8ddc5d3
author Daniel N Pettersson <danielnp@axis.com> 1515682812 +0100
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1518870072 +0100

cifs: Fix autonegotiate security settings mismatch

commit 9aca7e454415f7878b28524e76bebe1170911a88 upstream.

Autonegotiation gives a security settings mismatch error if the SMB
server selects an SMBv3 dialect that isn't SMB3.02. The exact error is
"protocol revalidation - security settings mismatch".
This can be tested using Samba v4.2 or by setting the global Samba
setting max protocol = SMB3_00.

The check that fails in smb3_validate_negotiate is the dialect
verification of the negotiate info response. This is because it tries
to verify against the protocol_id in the global smbdefault_values. The
protocol_id in smbdefault_values is SMB3.02.
In SMB2_negotiate the protocol_id in smbdefault_values isn't updated,
it is global so it probably shouldn't be, but server->dialect is.

This patch changes the check in smb3_validate_negotiate to use
server->dialect instead of server->vals->protocol_id. The patch works
with autonegotiate and when using a specific version in the vers mount
option.

Signed-off-by: Daniel N Pettersson <danielnp@axis.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>