From patchwork Tue May 26 18:53:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 225196 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90A7BC433E0 for ; Tue, 26 May 2020 19:32:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5AE2120849 for ; Tue, 26 May 2020 19:32:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590521564; bh=lZSkrCSWq5IHgh33Yymn5+HmpEzB3rSS5qKnFSXSWGU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tgdDLQKa6PyGKcMoQkDQSb259OmnB+QTq90QL4vQQIQWWh1m8AbQbhn/ZXqJHw5zj GCB6Ub+J2srm084NwuVAdEnep7kDjuHPdymfrRb4vcSrDWL9cFDKQOLeVIcLbbk7iq SxFmul5+jEX/6Kre/w/uoqNiEjQK5oI9gXBayeAM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390843AbgEZTck (ORCPT ); Tue, 26 May 2020 15:32:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:50494 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390058AbgEZS5R (ORCPT ); Tue, 26 May 2020 14:57:17 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 790CB2151B; Tue, 26 May 2020 18:57:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519436; bh=lZSkrCSWq5IHgh33Yymn5+HmpEzB3rSS5qKnFSXSWGU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hQr/oyezG9ZQgh/eZmxGIpxAFqbLrH8hWA2SMoEZhwC6/zPl7dB2nHtwh0x4NadvJ K7E5AmusEIS6FO/AWkg1QqomajHynvF6K4Y0wSlaX7gjJxMSaAyCJxD2YPK3TCcc2q r89vo6ha6WPonYx3GjziLe1snJnpSEIyf15OfkFM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, greg@kroah.com Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Guillaume Nault , "David S. Miller" , Giuliano Procida Subject: [PATCH 4.4 50/65] l2tp: hold tunnel while processing genl delete command Date: Tue, 26 May 2020 20:53:09 +0200 Message-Id: <20200526183923.358855333@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526183905.988782958@linuxfoundation.org> References: <20200526183905.988782958@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Guillaume Nault commit bb0a32ce4389e17e47e198d2cddaf141561581ad upstream. l2tp_nl_cmd_tunnel_delete() needs to take a reference on the tunnel, to prevent it from being concurrently freed by l2tp_tunnel_destruct(). Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Giuliano Procida Signed-off-by: Greg Kroah-Hartman --- net/l2tp/l2tp_netlink.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/net/l2tp/l2tp_netlink.c +++ b/net/l2tp/l2tp_netlink.c @@ -280,8 +280,8 @@ static int l2tp_nl_cmd_tunnel_delete(str } tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]); - tunnel = l2tp_tunnel_find(net, tunnel_id); - if (tunnel == NULL) { + tunnel = l2tp_tunnel_get(net, tunnel_id); + if (!tunnel) { ret = -ENODEV; goto out; } @@ -291,6 +291,8 @@ static int l2tp_nl_cmd_tunnel_delete(str l2tp_tunnel_delete(tunnel); + l2tp_tunnel_dec_refcount(tunnel); + out: return ret; }