cifs: reconnect helper should set reconnect for the right channel

commit c3326a6 upstream.

We introduced a helper function to be used by non-cifsd threads to
mark the connection for reconnect. For multichannel, when only
a particular channel needs to be reconnected, this had a bug.

This change fixes that by marking that particular channel
for reconnect.

Fixes: dca6581 ("cifs: use a different reconnect helper for non-cifsd threads")
Cc: stable@vger.kernel.org
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/smb/client/connect.c

@@ -156,13 +156,14 @@ cifs_signal_cifsd_for_reconnect(struct TCP_Server_Info *server,
 	/* If server is a channel, select the primary channel */
 	pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
 
-	spin_lock(&pserver->srv_lock);
+	/* if we need to signal just this channel */
 	if (!all_channels) {
-		pserver->tcpStatus = CifsNeedReconnect;
-		spin_unlock(&pserver->srv_lock);
+		spin_lock(&server->srv_lock);
+		if (server->tcpStatus != CifsExiting)
+			server->tcpStatus = CifsNeedReconnect;
+		spin_unlock(&server->srv_lock);
 		return;
 	}
-	spin_unlock(&pserver->srv_lock);
 
 	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {