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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS 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 83B50C11F64 for ; Thu, 1 Jul 2021 16:26:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6105E613E3 for ; Thu, 1 Jul 2021 16:26:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232133AbhGAQ2t (ORCPT ); Thu, 1 Jul 2021 12:28:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229664AbhGAQ2t (ORCPT ); Thu, 1 Jul 2021 12:28:49 -0400 Received: from mail-il1-x136.google.com (mail-il1-x136.google.com [IPv6:2607:f8b0:4864:20::136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 84FD3C061762; Thu, 1 Jul 2021 09:26:18 -0700 (PDT) Received: by mail-il1-x136.google.com with SMTP id s19so6960479ilj.1; Thu, 01 Jul 2021 09:26:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:message-id:in-reply-to:references:subject :mime-version:content-transfer-encoding; bh=2XdotHd/9Rh+BK080jiiJOcyvm9QE25ghUxjFU5Oqes=; b=vJW/sAkOCdqpQ/P8b8laZirQ+Hocgjyr25TnK08SYVLhB2jQ7/6pCsVYGud8ot2VG3 Q4sXnzUzzrvrKpUq72jCT4SxUs0wMwYDM/gZke/7+UejTNFy0LjA6HU6wMJy5CH/84vh OswxV/dO6KpnCMbhnPfx1zvzdvQEiTYDmnR+csBtTdsII0LhJTHIJlyblB142Ouyn+eq HV/YSX9qpphSoeJjlqQJGJmsAGIIG7VEOXdZtmTEg0NiU68jZnJFlodkm7/4ChYycSTj BMiIwqiIXlNv15F5A8XJpnPi06gC6tMgvWvWH97Wc1t/reA63wR/XDXUhRBa5Kc3BHyG nhBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:message-id:in-reply-to :references:subject:mime-version:content-transfer-encoding; bh=2XdotHd/9Rh+BK080jiiJOcyvm9QE25ghUxjFU5Oqes=; b=XCK+Axg67xby4vCWF7K03z70Xx5W2pIrj0l/UTb0TrvbAL6oo1mIi5s8zZ+CpYOn7v dyoydMcfBNC8Nlr2maShSoSquDcNEPwTzv9ry+z8CRd7WnCUKTZ/SPMCExQVHcHmUBV9 Qc1SyePt1waYsI1PUSzjPvupuoaE8fCgTLbSPxrF6Mr3lX+WjH6U8YHSQJuaK4tFGo/u pEt3nhrDdaaSJA2QILLxUzy8KXcMmTckNG5X60c+5RDwRO+W8Jh+ztzjKtidmaBQmpfx Qzup50uzhsCeeDgb/5D1fQz6xhNGY2qxHYa/qG1BE8dpOLqGmZrWk/2Ld1rbKcDvdMZJ L0Sw== X-Gm-Message-State: AOAM5311LlnBIo13rvEcfcq1ULgxwyH4n2yz4Qub3WumKsEQYxSCJQ+k cJJheDJa3SM5FADGTQfiYX0= X-Google-Smtp-Source: ABdhPJwJIgpDOEQ5GhWIVardLzgHkCSkA2L+LOW2yL7j/HnvWhEYfjJfwdCrYhRLqX+YoYX5K73EIQ== X-Received: by 2002:a92:a304:: with SMTP id a4mr161073ili.197.1625156777970; Thu, 01 Jul 2021 09:26:17 -0700 (PDT) Received: from localhost ([172.243.157.240]) by smtp.gmail.com with ESMTPSA id e14sm201023ilc.47.2021.07.01.09.26.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 01 Jul 2021 09:26:17 -0700 (PDT) Date: Thu, 01 Jul 2021 09:26:07 -0700 From: John Fastabend To: Jakub Sitnicki , Cong Wang Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Cong Wang , Jiang Wang , Daniel Borkmann , John Fastabend , Lorenz Bauer Message-ID: <60ddec9f5abd6_3fe24208c3@john-XPS-13-9370.notmuch> In-Reply-To: <877diarpsz.fsf@cloudflare.com> References: <20210701061656.34150-1-xiyou.wangcong@gmail.com> <877diarpsz.fsf@cloudflare.com> Subject: Re: [Patch bpf v2] skmsg: check sk_rcvbuf limit before queuing to ingress_skb Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Jakub Sitnicki wrote: > On Thu, Jul 01, 2021 at 08:16 AM CEST, Cong Wang wrote: > > From: Cong Wang > > > > Jiang observed OOM frequently when testing our AF_UNIX/UDP > > proxy. This is due to the fact that we do not actually limit > > the socket memory before queueing skb to ingress_skb. We > > charge the skb memory later when handling the psock backlog, > > but it is not limited either. > > > > This patch adds checks for sk->sk_rcvbuf right before queuing > > to ingress_skb and drops packets if this limit exceeds. This > > is very similar to UDP receive path. Ideally we should set the > > skb owner before this check too, but it is hard to make TCP > > happy about sk_forward_alloc. > > > > Reported-by: Jiang Wang > > Cc: Daniel Borkmann > > Cc: John Fastabend > > Cc: Lorenz Bauer > > Cc: Jakub Sitnicki > > Signed-off-by: Cong Wang > > --- > > Acked-by: Jakub Sitnicki > > By saying that it is hard to make TCP happy about sk_forward_alloc, I'm > guessing you're referring to problems described in 144748eb0c44 ("bpf, > sockmap: Fix incorrect fwd_alloc accounting") [1]? I have a couple fixes on my stack here I'm testing that clean up the tear down logic. Once thats in place maybe its as simple as adding the owner_r bits and calling the destructor to ensure memory accounting happens earlier so these ingress_skb packets are accounted for. I'll flush those out today, maybe it will be clear then. > > Thanks for the fix. > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=144748eb0c445091466c9b741ebd0bfcc5914f3d > > [...]