From mboxrd@z Thu Jan 1 00:00:00 1970 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=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 987BDC433E0 for ; Mon, 10 Aug 2020 15:28:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 623E722CF7 for ; Mon, 10 Aug 2020 15:28:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597073305; bh=u/EJEC7fwlnjfYmjRVebmZuNlug14uzNDm4KhwNNuzs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=vupM3XI0iP6RXs17RYHuTzUUkcA+Q9ydfkXZlYVASYSrBJCf/VC9cBjGeCa2+2XcX wDc6gTi0hRgTprJ2RNwUTxeyS4qS4ayw78l8wqx+nUDIDzW1IOkmr/bmCfDNgJ80+p KdKwX+W6a3DhZemg/2YmsiohhZM2se7oz931Fj2Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728857AbgHJP2X (ORCPT ); Mon, 10 Aug 2020 11:28:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:34312 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728533AbgHJP2N (ORCPT ); Mon, 10 Aug 2020 11:28:13 -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 650A122B47; Mon, 10 Aug 2020 15:28:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597073292; bh=u/EJEC7fwlnjfYmjRVebmZuNlug14uzNDm4KhwNNuzs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=US/L+ZmnemVgUoYp4LsbREieE1xEYHXjA3DXwFfRcegljFdTQEzH91myUhnL0Nidm H8j3QX9s0jjFCyqGD+q1NENBXmbiJXw1Ub2DtbcIiSZuI/CGFMbVn/5I/BTOoLluGw 0osEb7hnvAgKNESRDCfDWxqPcObyricZbFIjwpgc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiyu Yang , Xin Tan , David Ahern , "David S. Miller" Subject: [PATCH 5.4 52/67] ipv6: Fix nexthop refcnt leak when creating ipv6 route info Date: Mon, 10 Aug 2020 17:21:39 +0200 Message-Id: <20200810151812.040621550@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200810151809.438685785@linuxfoundation.org> References: <20200810151809.438685785@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiyu Yang [ Upstream commit 706ec919164622ff5ce822065472d0f30a9e9dd2 ] ip6_route_info_create() invokes nexthop_get(), which increases the refcount of the "nh". When ip6_route_info_create() returns, local variable "nh" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of ip6_route_info_create(). When nexthops can not be used with source routing, the function forgets to decrease the refcnt increased by nexthop_get(), causing a refcnt leak. Fix this issue by pulling up the error source routing handling when nexthops can not be used with source routing. Fixes: f88d8ea67fbd ("ipv6: Plumb support for nexthop object in a fib6_info") Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/route.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3686,14 +3686,14 @@ static struct fib6_info *ip6_route_info_ rt->fib6_src.plen = cfg->fc_src_len; #endif if (nh) { - if (!nexthop_get(nh)) { - NL_SET_ERR_MSG(extack, "Nexthop has been deleted"); - goto out; - } if (rt->fib6_src.plen) { NL_SET_ERR_MSG(extack, "Nexthops can not be used with source routing"); goto out; } + if (!nexthop_get(nh)) { + NL_SET_ERR_MSG(extack, "Nexthop has been deleted"); + goto out; + } rt->nh = nh; fib6_nh = nexthop_fib6_nh(rt->nh); } else {