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=-10.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 DCE65C43387 for ; Mon, 7 Jan 2019 12:48:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A185120651 for ; Mon, 7 Jan 2019 12:48:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546865301; bh=msEz2+G0MAl9izrXLnGqCI1CfLSaTD8a1Vefw4CMrPc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XABQWPPJmHI6sJtIiUbRFwcsSCFLLdDeNpv8TCTyT1YHHlGvjIe0JWfgcf+c5JV8R O3qZp5Gl7ohVnK70BOzxKS/s5cP4Jxr7O+GAtaugfPWMrXWkxplN2uPhBJRcRtCo1T 6Ah7EOYhM07HGY+9Asl671BTyvd46TwozTGDl5I0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729149AbfAGMsU (ORCPT ); Mon, 7 Jan 2019 07:48:20 -0500 Received: from mail.kernel.org ([198.145.29.99]:38866 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729137AbfAGMsR (ORCPT ); Mon, 7 Jan 2019 07:48:17 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 E4E102089F; Mon, 7 Jan 2019 12:48:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546865296; bh=msEz2+G0MAl9izrXLnGqCI1CfLSaTD8a1Vefw4CMrPc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=K3yuCA1yApRUqtRokhBFGDuZPCg6OtalXtKapI7AI06GXjNDdzdoVnKJu2hO/EQk0 ncAJu2p9KFZeNXOUgmGLIpmb25qhogHKxKvh8Dr0fqi1aZ/nkq6KrGEcfzspbIYL6R 0RYVz2KtOdx7ZnkIin4iPgb445XSOMaRzG/lwkic= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jianlin Shi , Stefano Brivio , David Ahern , "David S. Miller" Subject: [PATCH 4.19 047/170] ipv6: route: Fix return value of ip6_neigh_lookup() on neigh_create() error Date: Mon, 7 Jan 2019 13:31:14 +0100 Message-Id: <20190107104458.746734842@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190107104452.953560660@linuxfoundation.org> References: <20190107104452.953560660@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore 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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stefano Brivio [ Upstream commit 7adf3246092f5e87ed0fa610e8088fae416c581f ] In ip6_neigh_lookup(), we must not return errors coming from neigh_create(): if creation of a neighbour entry fails, the lookup should return NULL, in the same way as it's done in __neigh_lookup(). Otherwise, callers legitimately checking for a non-NULL return value of the lookup function might dereference an invalid pointer. For instance, on neighbour table overflow, ndisc_router_discovery() crashes ndisc_update() by passing ERR_PTR(-ENOBUFS) as 'neigh' argument. Reported-by: Jianlin Shi Fixes: f8a1b43b709d ("net/ipv6: Create a neigh_lookup for FIB entries") Signed-off-by: Stefano Brivio Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/route.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -210,7 +210,9 @@ struct neighbour *ip6_neigh_lookup(const n = __ipv6_neigh_lookup(dev, daddr); if (n) return n; - return neigh_create(&nd_tbl, daddr, dev); + + n = neigh_create(&nd_tbl, daddr, dev); + return IS_ERR(n) ? NULL : n; } static struct neighbour *ip6_dst_neigh_lookup(const struct dst_entry *dst,