SMB3: Validate negotiate request must always be signed

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@vger.kernel.org>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index ba58af747b43..5331631386a2 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1979,6 +1979,9 @@ SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
         } 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.sync_hdr.Flags |= SMB2_FLAGS_SIGNED;
 
         rc = SendReceive2(xid, ses, iov, n_iov, &resp_buftype, flags, &rsp_iov);
         cifs_small_buf_release(req);