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=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 98DFBC07E95 for ; Sun, 4 Jul 2021 13:10:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71A75613E5 for ; Sun, 4 Jul 2021 13:10:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229532AbhGDNNI (ORCPT ); Sun, 4 Jul 2021 09:13:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229530AbhGDNNI (ORCPT ); Sun, 4 Jul 2021 09:13:08 -0400 Received: from mail-lj1-x229.google.com (mail-lj1-x229.google.com [IPv6:2a00:1450:4864:20::229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77259C061574 for ; Sun, 4 Jul 2021 06:10:32 -0700 (PDT) Received: by mail-lj1-x229.google.com with SMTP id a6so20723941ljq.3 for ; Sun, 04 Jul 2021 06:10:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google; h=references:user-agent:from:to:cc:subject:in-reply-to:date :message-id:mime-version; bh=tPLRcPv1NPR6kIfLhu4yXv2ZwM15Pog1toqV70W4KYE=; b=N4Kw4GeICx4+Zu9hyCCs76JNuh7wl1BEd9ztGYKRYT6pMLcjuZOrtrlJfgzVz0WTlf ZQDOc74c6hFyOgi1mubaU4YbGqF9jfEZmTsgtQrmJJr+bKei7xyQ46enkwGyJOPvvH+Y ior284G4ZnJjY2Bx4ytJa1Igy1RL2YrCOG7t4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:references:user-agent:from:to:cc:subject :in-reply-to:date:message-id:mime-version; bh=tPLRcPv1NPR6kIfLhu4yXv2ZwM15Pog1toqV70W4KYE=; b=k8JWcuMrFfifU+X9DI4qAyJ4ZXuple30gcgiuqBYKJrvrTcwKxvsUWYkp+2pKxtrkf yB4udCYx1E994oBwt9lzCn1liIGc6g7UMIwJnU/gJ2ND2oOkPRnAv2YYHr8oGekrMfH7 udpL33yF8YJMDeVskzBXVUUX8C0buVgB+HlvIkNtno897WnBIbx/uiO9kaZjG+110yxH J6PzHQMK+b7W6JztRN0BUsZSVxdLoIpOZR5KTOV/QNrzzxyKNNmS65KLJqSyEgIUclHA X8HNbxKh5FaygX+jwpsH8hv3JsJz6Pp+OOKoKKLUxfVs94CFe0LvLtfX4kU/q6drN6z+ 3zlA== X-Gm-Message-State: AOAM530c68iwdv/pv0eWrZ9JUKbpudZOXFUXuRQ4yKna+KhgLHtBHXUP PPY134E9Re+w/cwoNPZ9CZV/5w== X-Google-Smtp-Source: ABdhPJwkVdg15dhviQ6aL0BGjXPAMwRLO3qZKcPrCox1F3IRe/RxVQ3CtUrPZAXV4srMl/JkAXZC+Q== X-Received: by 2002:a05:651c:4ce:: with SMTP id e14mr7145630lji.176.1625404230671; Sun, 04 Jul 2021 06:10:30 -0700 (PDT) Received: from cloudflare.com (79.191.58.233.ipv4.supernova.orange.pl. [79.191.58.233]) by smtp.gmail.com with ESMTPSA id s17sm368594ljg.28.2021.07.04.06.10.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 04 Jul 2021 06:10:29 -0700 (PDT) References: <20210701061656.34150-1-xiyou.wangcong@gmail.com> <60ddec01c651b_3fe24208dc@john-XPS-13-9370.notmuch> <875yxrs2sc.fsf@cloudflare.com> User-agent: mu4e 1.1.0; emacs 27.2 From: Jakub Sitnicki To: John Fastabend Cc: Cong Wang , netdev@vger.kernel.org, bpf@vger.kernel.org, Cong Wang , Jiang Wang , Daniel Borkmann , "Lorenz Bauer" Subject: Re: [Patch bpf v2] skmsg: check sk_rcvbuf limit before queuing to ingress_skb In-reply-to: <875yxrs2sc.fsf@cloudflare.com> Date: Sun, 04 Jul 2021 15:10:28 +0200 Message-ID: <874kdarzqz.fsf@cloudflare.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Sat, Jul 03, 2021 at 07:52 PM CEST, Jakub Sitnicki wrote: [...] > Then there is the case when a parser prog is attached. In this case the > skb is really gone if we drop it on redirect. > > In sk_psock_strp_read, we ignore the -EIO error from > sk_psock_verdict_apply, and return to tcp_read_sock how many bytes have > been parsed. > > sk->sk_data_ready > sk_psock_verdict_data_ready > ->read_sock(..., sk_psock_verdict_recv) > tcp_read_sock (used = copied = eaten) > strp_recv -> ret = eaten > __strp_recv -> ret = eaten > strp->cb.rcv_msg -> -EIO > sk_psock_verdict_apply -> -EIO > sk_psock_redirect -> -EIO Copy-paste error. The call chain for the parser case goes as so: sk->sk_data_ready sk_psock_strp_data_ready strp_data_ready strp_read_sock ->read_sock(..., strp_recv) tcp_read_sock (used = copied = skb->len) strp_recv -> ret = skb->len __strp_recv -> ret = skb->len (dummy parser case) strp->cb.rcv_msg -> -EIO sk_psock_verdict_apply -> -EIO sk_psock_redirect -> -EIO