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=-6.1 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=ham 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 32833C43381 for ; Thu, 21 Feb 2019 14:38:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 02BAD2086C for ; Thu, 21 Feb 2019 14:38:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550759897; bh=82SAn6VBjC8wyR9JZFYWZj8T5FJGWys/l3TaH3bYBqI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=vVKPpCXyhM1PuWBwiuNy8p48uLvVH/d7K5MZP+PrApjwvB6WtJBBhnVOD8kWUBsFZ 0MMz4U9WBK/ChL5xC2ERYyofI28zXcep9p0+Z/3M0WoMAdFO0DUgBI9P09ZkjaV1QA 5czaKw1i7eujyYZ/vIJ/jO9tFEPxulRKkrEZ+3+Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728632AbfBUOiP (ORCPT ); Thu, 21 Feb 2019 09:38:15 -0500 Received: from mail.kernel.org ([198.145.29.99]:59834 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727939AbfBUOiM (ORCPT ); Thu, 21 Feb 2019 09:38:12 -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 4DE4020838; Thu, 21 Feb 2019 14:38:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550759891; bh=82SAn6VBjC8wyR9JZFYWZj8T5FJGWys/l3TaH3bYBqI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QpjIPFx5QLPPYKIVSLeUo6P8JjLl+l7vDpTSmIGbB7NuBEmuLgwaDYRuqIUdBf/qX UPkqsDjR4WYmvR+XhljDXdNDBvVBXudwm8h5MY9MPO6s537223K0NJZQCs2sBQiHRL /Oh8nZQxpnHIftRja7qnBzdNTA5asNBAR/zCZnQ0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , soukjin bae , Neal Cardwell , Soheil Hassas Yeganeh , "David S. Miller" Subject: [PATCH 4.4 07/20] tcp: tcp_v4_err() should be more careful Date: Thu, 21 Feb 2019 15:35:37 +0100 Message-Id: <20190221141946.984750657@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190221141946.772985220@linuxfoundation.org> References: <20190221141946.772985220@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 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 2c4cc9712364c051b1de2d175d5fbea6be948ebf ] ICMP handlers are not very often stressed, we should make them more resilient to bugs that might surface in the future. If there is no packet in retransmit queue, we should avoid a NULL deref. Signed-off-by: Eric Dumazet Reported-by: soukjin bae Acked-by: Neal Cardwell Acked-by: Soheil Hassas Yeganeh Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/tcp_ipv4.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -466,14 +466,15 @@ void tcp_v4_err(struct sk_buff *icmp_skb if (sock_owned_by_user(sk)) break; + skb = tcp_write_queue_head(sk); + if (WARN_ON_ONCE(!skb)) + break; + icsk->icsk_backoff--; icsk->icsk_rto = tp->srtt_us ? __tcp_set_rto(tp) : TCP_TIMEOUT_INIT; icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX); - skb = tcp_write_queue_head(sk); - BUG_ON(!skb); - remaining = icsk->icsk_rto - min(icsk->icsk_rto, tcp_time_stamp - tcp_skb_timestamp(skb));