From: Steve French <stfrench@microsoft.com>
Date: Thu, 25 Apr 2024 16:30:16 +0000 (-0500)
Subject: smb3: missing lock when picking channel
X-Git-Tag: v6.9-rc6~6^2~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8094a600245e9b28eb36a13036f202ad67c1f887;p=thirdparty%2Flinux.git

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@vger.kernel.org
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
---

diff --git a/fs/smb/client/transport.c b/fs/smb/client/transport.c
index 994d701934329..e1a79e031b28c 100644
--- a/fs/smb/client/transport.c
+++ b/fs/smb/client/transport.c
@@ -1057,9 +1057,11 @@ 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