FAILED: patch "[PATCH] SMB3: Validate negotiate request must always be signed" failed to apply to 4.9-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From 4587eee04e2ac7ac3ac9fa2bc164fb6e548f99cd Mon Sep 17 00:00:00 2001
From: Steve French <smfrench@gmail.com>
Date: Wed, 25 Oct 2017 15:58:31 -0500
Subject: [PATCH] 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>

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);