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,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 09CF7C4360F for ; Thu, 21 Feb 2019 14:38:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD2D72084D for ; Thu, 21 Feb 2019 14:38:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550759915; bh=u94E0b/Ew+On4fxau3+yrutc87ENd8vnIHw9pn5h8t8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bzz+IvEFXbx68caH/iPfhMjOvGHp6rOZ99drMMC5/edAatZXypFHdYV4fgY4sng6G XGbIjef7MNUvTGmyRDpQBXXtxiy2eKHwEyhhrurUtNJB+aBLzhAa5vgWRb2LmxqJFZ Ho3PSzPGjESBJiTNfRaSjMLJLaw//rvwqz4HMzs0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728699AbfBUOie (ORCPT ); Thu, 21 Feb 2019 09:38:34 -0500 Received: from mail.kernel.org ([198.145.29.99]:60296 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728017AbfBUOib (ORCPT ); Thu, 21 Feb 2019 09:38:31 -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 EED6F20838; Thu, 21 Feb 2019 14:38:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550759910; bh=u94E0b/Ew+On4fxau3+yrutc87ENd8vnIHw9pn5h8t8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hYbiyaucQyzkRFeGfXbd6qdzfy668jXDKhuHWWiAn5ttOCeJwi/5/8I+5XVgcLNuD Jb9delbG6aSt3SPscxRBw3kLz8zH9BMdxiKIIJONw9HykEyk33aNpZtJ8dPDSzE778 sSZ1sCWqcOviiQ+MGsQWmCS2/BUnjcBwA7A/LN4A= 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 4.9 11/20] tcp: tcp_v4_err() should be more careful Date: Thu, 21 Feb 2019 15:35:49 +0100 Message-Id: <20190221125243.503417436@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190221125242.153179182@linuxfoundation.org> References: <20190221125242.153179182@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 4.9-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 @@ -464,14 +464,15 @@ 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));