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 A15D0C433E1 for ; Mon, 20 Jul 2020 15:49:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 604742064B for ; Mon, 20 Jul 2020 15:49:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595260185; bh=YL+fDmrIp0AJVr4B8vAuONxS7rpJX/UrdUgwnouQVKk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=o5L3w1UAKR1gv+PwquANFiqmyHfYuT4dA684RrXeF+n4qRWL8YpQ09KKwZoks9Wz0 UG5nuZFsl0V1dmdhTUjilbDRVwpx91/4TBCqGOFVlduJxrDU4NPXt1m4pdpVZs1yGi eXRQraRyINMfhHL9iDS7Pj1PKy1FFPE4QSFq/rQY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730644AbgGTPto (ORCPT ); Mon, 20 Jul 2020 11:49:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:45842 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729893AbgGTPtk (ORCPT ); Mon, 20 Jul 2020 11:49:40 -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 A5B442064B; Mon, 20 Jul 2020 15:49:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595260180; bh=YL+fDmrIp0AJVr4B8vAuONxS7rpJX/UrdUgwnouQVKk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JnoLjrD3FgAPnuT+kVigvGFewOIYZXvP7MzueVEdvujlBC48rXSxXYFHgKQXmqThj tU3oVXpky8Kt76m+2qLoQIi9NizfTUfsyHFB0xQk3iFPM0bTi6PqdNR7PS1bkA7FH9 NBEjWOcWC2s8UelvTjQ66E9y7bFQk7pKZdH8A/9Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , "David S. Miller" Subject: [PATCH 4.19 010/133] tcp: fix SO_RCVLOWAT possible hangs under high mem pressure Date: Mon, 20 Jul 2020 17:35:57 +0200 Message-Id: <20200720152804.232247109@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152803.732195882@linuxfoundation.org> References: <20200720152803.732195882@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: Eric Dumazet [ Upstream commit ba3bb0e76ccd464bb66665a1941fabe55dadb3ba ] Whenever tcp_try_rmem_schedule() returns an error, we are under trouble and should make sure to wakeup readers so that they can drain socket queues and eventually make room. Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/tcp_input.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4494,6 +4494,7 @@ static void tcp_data_queue_ofo(struct so if (unlikely(tcp_try_rmem_schedule(sk, skb, skb->truesize))) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFODROP); + sk->sk_data_ready(sk); tcp_drop(sk, skb); return; } @@ -4739,6 +4740,7 @@ queue_and_out: sk_forced_mem_schedule(sk, skb->truesize); else if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVQDROP); + sk->sk_data_ready(sk); goto drop; }