lightly updated with Bharath's suggestions of moving cifs_free_ipc()
out of the spinlock
See attached.
On Wed, Apr 26, 2023 at 10:09 PM Steve French <smfrench@xxxxxxxxx> wrote:
>
> Coverity noted a place where we were not grabbing
> the ses_lock when setting (and checking) ses_status.
>
> Addresses-Coverity: 1536833 ("Data race condition (MISSING_LOCK)")
>
>
> --
> Thanks,
>
> Steve
--
Thanks,
Steve
From a8c63ad9e478a6099e20277001aea07561d45bea Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@xxxxxxxxxxxxx>
Date: Wed, 26 Apr 2023 22:01:31 -0500
Subject: [PATCH] cifs: missing lock when updating session status
Coverity noted a place where we were not grabbing
the ses_lock when setting (and checking) ses_status.
Addresses-Coverity: 1536833 ("Data race condition (MISSING_LOCK)")
Reviewed-by: Bharath SM <bharathsm@xxxxxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
---
fs/cifs/connect.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 1cbb90587995..7bfef741f758 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1916,18 +1916,22 @@ void cifs_put_smb_ses(struct cifs_ses *ses)
/* ses_count can never go negative */
WARN_ON(ses->ses_count < 0);
+ spin_lock(&ses->ses_lock);
if (ses->ses_status == SES_GOOD)
ses->ses_status = SES_EXITING;
- cifs_free_ipc(ses);
-
if (ses->ses_status == SES_EXITING && server->ops->logoff) {
+ spin_unlock(&ses->ses_lock);
+ cifs_free_ipc(ses);
xid = get_xid();
rc = server->ops->logoff(xid, ses);
if (rc)
cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
__func__, rc);
_free_xid(xid);
+ } else {
+ spin_unlock(&ses->ses_lock);
+ cifs_free_ipc(ses);
}
spin_lock(&cifs_tcp_ses_lock);
--
2.34.1
