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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,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 1527EC28CC3 for ; Tue, 4 Jun 2019 23:31:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D83B1206C1 for ; Tue, 4 Jun 2019 23:31:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559691109; bh=66hOY2fBtQRs/WlfFucZlqG6SUvnQxfmiGeG7HznvFQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=iu96cvFIyMKUsBVFU1VsDMjihDnh5PLEZl8MrX5FmdO5kj7HjRFUfuM48KPaaC8Xi AFsO1owO1LJQAFnVZbWNx6GhnJ8BubDmBoRSjg7FCatDAxjq5bpc3NQ2NCJ+KPQoHw OAEWnpN0mOqdYLjfpm4FGwqxdZGWZjXh2pXgy5Ns= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727001AbfFDXWw (ORCPT ); Tue, 4 Jun 2019 19:22:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:33130 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727009AbfFDXWv (ORCPT ); Tue, 4 Jun 2019 19:22:51 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 36DF420863; Tue, 4 Jun 2019 23:22:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559690571; bh=66hOY2fBtQRs/WlfFucZlqG6SUvnQxfmiGeG7HznvFQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=szIKkU80u6EavR5yIQEaETIy6ElQRBKN1jhNvXWZOWNoypc+qMyhuZ2wuX0VwISt4 jSCed1sXaJcCKo2UquS7MHxrvcudAsTAczQwTh6yo/Q9Xnqws3gXqM6FxddOsnAs/x zZXV/mhgF0Or7BBFy7IGQIrECC4uuWgNJ0Td1vpE= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: John Fastabend , Arika Chen , Daniel Borkmann , Sasha Levin , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 5.1 24/60] bpf, tcp: correctly handle DONT_WAIT flags and timeo == 0 Date: Tue, 4 Jun 2019 19:21:34 -0400 Message-Id: <20190604232212.6753-24-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190604232212.6753-1-sashal@kernel.org> References: <20190604232212.6753-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: John Fastabend [ Upstream commit 5fa2ca7c4a3fc176f31b495e1a704862d8188b53 ] The tcp_bpf_wait_data() routine needs to check timeo != 0 before calling sk_wait_event() otherwise we may see unexpected stalls on receiver. Arika did all the leg work here I just formatted, posted and ran a few tests. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Reported-by: Arika Chen Suggested-by: Arika Chen Signed-off-by: John Fastabend Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin --- net/ipv4/tcp_bpf.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index 4a619c85daed..3d1e15401384 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -27,7 +27,10 @@ static int tcp_bpf_wait_data(struct sock *sk, struct sk_psock *psock, int flags, long timeo, int *err) { DEFINE_WAIT_FUNC(wait, woken_wake_function); - int ret; + int ret = 0; + + if (!timeo) + return ret; add_wait_queue(sk_sleep(sk), &wait); sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); -- 2.20.1