[PATCH 4.4 03/97] SMB3: Validate negotiate request must always be signed

From: Greg Kroah-Hartman
Date: Fri Mar 23 2018 - 06:13:27 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Steve French <smfrench@xxxxxxxxx>

commit 4587eee04e2ac7ac3ac9fa2bc164fb6e548f99cd upstream.

According to MS-SMB2 3.2.55 validate_negotiate request must
always be signed. Some Windows can fail the request if you send it unsigned

See kernel bugzilla bug 197311

CC: Stable <stable@xxxxxxxxxxxxxxx>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
Signed-off-by: Srivatsa S. Bhat <srivatsa@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/cifs/smb2pdu.c | 3 +++
1 file changed, 3 insertions(+)

--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1558,6 +1558,9 @@ SMB2_ioctl(const unsigned int xid, struc
} else
iov[0].iov_len = get_rfc1002_length(req) + 4;

+ /* validate negotiate request must be signed - see MS-SMB2 3.2.5.5 */
+ if (opcode == FSCTL_VALIDATE_NEGOTIATE_INFO)
+ req->hdr.Flags |= SMB2_FLAGS_SIGNED;

rc = SendReceive2(xid, ses, iov, num_iovecs, &resp_buftype, 0);
rsp = (struct smb2_ioctl_rsp *)iov[0].iov_base;