From patchwork Tue May 14 04:42:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Fastabend X-Patchwork-Id: 1099220 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="CkJevJMH"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 4534mC4NVXz9sCJ for ; Tue, 14 May 2019 14:42:19 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725985AbfENEmR (ORCPT ); Tue, 14 May 2019 00:42:17 -0400 Received: from mail-it1-f194.google.com ([209.85.166.194]:39892 "EHLO mail-it1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725562AbfENEmR (ORCPT ); Tue, 14 May 2019 00:42:17 -0400 Received: by mail-it1-f194.google.com with SMTP id 9so2646132itf.4; Mon, 13 May 2019 21:42:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:from:to:cc:date:message-id:user-agent:mime-version :content-transfer-encoding; bh=OK+amOIyoJqoqKtJQ8fZgnv70LQ09z+QT/CtisP33vA=; b=CkJevJMHG3DdojgneEqgpSlVEXQ37TfODb/h8CqSiAEVrLOZPv8A3fw13LV+ZAtFSS JBOPiQUAnNnqgyTg5oWVpNThm6q8ul2ZsBHSg7tiiEnBF9F7JiOFVoDz+FJORULv+Kce ykPV57bD0R5OPnJtIDIG4T+KOs595ErbNfF39VCxnd88Fy72s6EGm6NB1zOZCt/pn2bp SFRIt2CryJJMAN6w4l6vuPUT2Jr4J1t2ErfUiYCm/lcxGFhC+n7N0TdhFHYTpvt0Kyk9 NLO9naZF1/Z+PYyw1vNbq8XYTNoVgInGzmWmPT+hjHH9Zx+xIFJqUU5U+vBN3YcP6vlG 7azA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:date:message-id:user-agent :mime-version:content-transfer-encoding; bh=OK+amOIyoJqoqKtJQ8fZgnv70LQ09z+QT/CtisP33vA=; b=r6aaWx7Fv4mOrV62i4QmrXsUZjgD/DSSyADMUrwa3ZPpfVcy76uPZOm9dPXsRlZKbI XI/d75L3FBLLseFJd7BrSp2KHLBUKbKivCrV1jkNsRklcPBQqn4A+hB0Qo4UaFiDr5cv REMqa5Efnpf5VRT8rHkjJmA3TWPrZBndfLSUipEV6xpvVlMtkE+beFuamf17trTPXhaP BMcd3Lpl7PqWT3jGcxS6ey24KeQmx1ZUVQpXvupE7HUT60qW0c9l0u3YE6CgYvTtyqZm whmOPB/6udOvaSTIATY3WggRrlRA1+i7aWel6mp+tbsARsm/CHEGA4e5JcB6s8TMdfF+ zozA== X-Gm-Message-State: APjAAAUMYFpgMRwRrvPo6KX16pBa4r6yDpnkPtes661v+wroqQKdC0Hm iTM0Xj9DIvpcmCOaBMT7qmr9C+Kc/7Q= X-Google-Smtp-Source: APXvYqw8jHakmSmdEon2t+dwXLuxZIJwyxhTyGr8bCIcsyfoXksr0nNZpu8ulFNNIAcokFlwCfeb+Q== X-Received: by 2002:a02:37d7:: with SMTP id r206mr22245076jar.127.1557808936273; Mon, 13 May 2019 21:42:16 -0700 (PDT) Received: from [127.0.1.1] ([184.63.162.180]) by smtp.gmail.com with ESMTPSA id g13sm5605818iom.46.2019.05.13.21.42.10 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 13 May 2019 21:42:15 -0700 (PDT) Subject: [bpf PATCH] net: tcp_bpf, correctly handle DONT_WAIT flags and timeo == 0 From: John Fastabend To: ast@kernel.org, daniel@iogearbox.net Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, john.fastabend@gmail.com Date: Mon, 13 May 2019 21:42:03 -0700 Message-ID: <155780892372.10726.16677541867391282805.stgit@john-XPS-13-9360> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-Id: netdev.vger.kernel.org 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 formaatted, 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 --- 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 1bb7321a256d..27206b2064db 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);