[PATCH][SMB3 client] missing lock when picking channel

[Steve French <smfrench@xxxxxxxxx>]

Coverity spotted a place where we should have been holding the
channel lock when accessing the ses channel index.

Addresses-Coverity: 1582039 ("Data race condition (MISSING_LOCK)")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
---
 fs/smb/client/transport.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/smb/client/transport.c b/fs/smb/client/transport.c
index 443b4b89431d..fc0ddc75abc9 100644
--- a/fs/smb/client/transport.c
+++ b/fs/smb/client/transport.c
@@ -1059,9 +1059,11 @@ struct TCP_Server_Info
*cifs_pick_channel(struct cifs_ses *ses)
  index = (uint)atomic_inc_return(&ses->chan_seq);
  index %= ses->chan_count;
  }
+
+ server = ses->chans[index].server;
  spin_unlock(&ses->chan_lock);

- return ses->chans[index].server;
+ return server;
 }

-- 
Thanks,

Steve

From 5ec995c33cc30f1cfb26ab0126c077ca82f64a06 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@xxxxxxxxxxxxx>
Date: Thu, 25 Apr 2024 11:30:16 -0500
Subject: [PATCH 2/2] smb3: missing lock when picking channel

Coverity spotted a place where we should have been holding the
channel lock when accessing the ses channel index.

Addresses-Coverity: 1582039 ("Data race condition (MISSING_LOCK)")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
---
 fs/smb/client/transport.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/smb/client/transport.c b/fs/smb/client/transport.c
index 443b4b89431d..fc0ddc75abc9 100644
--- a/fs/smb/client/transport.c
+++ b/fs/smb/client/transport.c
@@ -1059,9 +1059,11 @@ struct TCP_Server_Info *cifs_pick_channel(struct cifs_ses *ses)
 		index = (uint)atomic_inc_return(&ses->chan_seq);
 		index %= ses->chan_count;
 	}
+
+	server = ses->chans[index].server;
 	spin_unlock(&ses->chan_lock);
 
-	return ses->chans[index].server;
+	return server;
 }
 
 int
-- 
2.40.1