FAILED: patch "[PATCH] cifs: fix uninitialised lease_key in open_shroot()" failed to apply to 4.19-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.19-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 0fe0781f29dd8ab618999e6bda33c782ebbdb109 Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <pc@cjr.nz>
Date: Mon, 20 Apr 2020 23:44:24 -0300
Subject: [PATCH] cifs: fix uninitialised lease_key in open_shroot()

SMB2_open_init() expects a pre-initialised lease_key when opening a
file with a lease, so set pfid->lease_key prior to calling it in
open_shroot().

This issue was observed when performing some DFS failover tests and
the lease key was never randomly generated.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index b36c46f48705..f829f4165d38 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -687,6 +687,11 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
 	if (smb3_encryption_required(tcon))
 		flags |= CIFS_TRANSFORM_REQ;
 
+	if (!server->ops->new_lease_key)
+		return -EIO;
+
+	server->ops->new_lease_key(pfid);
+
 	memset(rqst, 0, sizeof(rqst));
 	resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER;
 	memset(rsp_iov, 0, sizeof(rsp_iov));