This is a note to let you know that I've just added the patch titled
cifs: release auth_key.response for reconnect.
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cifs-release-auth_key.response-for-reconnect.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From f5c4ba816315d3b813af16f5571f86c8d4e897bd Mon Sep 17 00:00:00 2001
From: Shu Wang <shuwang@xxxxxxxxxx>
Date: Fri, 8 Sep 2017 18:48:33 +0800
Subject: cifs: release auth_key.response for reconnect.
From: Shu Wang <shuwang@xxxxxxxxxx>
commit f5c4ba816315d3b813af16f5571f86c8d4e897bd upstream.
There is a race that cause cifs reconnect in cifs_mount,
- cifs_mount
- cifs_get_tcp_session
- [ start thread cifs_demultiplex_thread
- cifs_read_from_socket: -ECONNABORTED
- DELAY_WORK smb2_reconnect_server ]
- cifs_setup_session
- [ smb2_reconnect_server ]
auth_key.response was allocated in cifs_setup_session, and
will release when the session destoried. So when session re-
connect, auth_key.response should be check and released.
Tested with my system:
CIFS VFS: Free previous auth_key.response = ffff8800320bbf80
A simple auth_key.response allocation call trace:
- cifs_setup_session
- SMB2_sess_setup
- SMB2_sess_auth_rawntlmssp_authenticate
- build_ntlmssp_auth_blob
- setup_ntlmv2_rsp
Signed-off-by: Shu Wang <shuwang@xxxxxxxxxx>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
Reviewed-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/cifs/connect.c | 8 ++++++++
1 file changed, 8 insertions(+)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -4060,6 +4060,14 @@ cifs_setup_session(const unsigned int xi
cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
server->sec_mode, server->capabilities, server->timeAdj);
+ if (ses->auth_key.response) {
+ cifs_dbg(VFS, "Free previous auth_key.response = %p\n",
+ ses->auth_key.response);
+ kfree(ses->auth_key.response);
+ ses->auth_key.response = NULL;
+ ses->auth_key.len = 0;
+ }
+
if (server->ops->sess_setup)
rc = server->ops->sess_setup(xid, ses, nls_info);
Patches currently in stable-queue which might be from shuwang@xxxxxxxxxx are
queue-4.4/cifs-release-cifs-root_cred-after-exit_cifs.patch
queue-4.4/cifs-release-auth_key.response-for-reconnect.patch