smb3: fix incorrect number of credits when ioctl MaxOutputResponse > 64K

smb3: fix incorrect number of credits when ioctl MaxOutputResponse > 64K

commit e80ddeb2f70ebd0786aa7cdba3e58bc931fa0bb5 upstream.

We were not checking to see if ioctl requests asked for more than
64K (ie when CIFSMaxBufSize was > 64K) so when setting larger
CIFSMaxBufSize then ioctls would fail with invalid parameter errors.
When requests ask for more than 64K in MaxOutputResponse then we
need to ask for more than 1 credit.

Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>