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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 78427C43381 for ; Wed, 6 Mar 2019 16:31:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 430DC206DD for ; Wed, 6 Mar 2019 16:31:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fZWwvR9C" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727436AbfCFQbZ (ORCPT ); Wed, 6 Mar 2019 11:31:25 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:44561 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726127AbfCFQbZ (ORCPT ); Wed, 6 Mar 2019 11:31:25 -0500 Received: by mail-pf1-f195.google.com with SMTP id a3so9011284pff.11 for ; Wed, 06 Mar 2019 08:31:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=vM7RbfAaFUSzHnkm8ChU9rZ6kZUCjUnjpt2t8BMCo7s=; b=fZWwvR9CGVXnP59Hv/0gN+UD65vDOdZsiuZoKTmE4uX3Vu8DEhn1WVpPT/oC6Okwub 3JnbGkNYxhmJPgB/+AsaJ2oynONypwvqOEr+XBM1eO5aqk0VQJ7y0MjprUTy0sgs/8zG UPXZYVSY8qo1dm53s+8zVZIG9TLg+qeEJgauven+eS6Xj2e3+Vbn/xfIhapErd+XrUqy Bw/N0mdCl8Neg8+L2dbVGjIJWpWwhAo05FGfhIYjRq7paV7IaDZjUSszJuGy5wPhcYtf DqoSAqHf5R0KFyjvJWVHVcINMEr0rVWt88+IbkAB96FUeXejn+BeLskLE5zFGp0AV2r8 NTww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=vM7RbfAaFUSzHnkm8ChU9rZ6kZUCjUnjpt2t8BMCo7s=; b=ISY1Uw8lqZQ1VAEYkkwM09FkeisMYXXdzaI6XJ/W+LA0Jqas9uUV8voyBfH1ZJlP+Z u1AP4CUIiLefy8NWbTC7+Jw6ZxTDmC4tanN4f7i1RRmYXJxyCIBJJ9hzOeJBichIo2nw EUSQYwY2JorMeHiqS+KJ04zETqd40o6kT0NL5NvcWtt79zQ2g/O2pb0+Ui4cgerkI+9e bPNp27GL7Yx3J3cO84JvydN8mAeyjxiV4rEvv37amyctqG7bts1a7OH9/Qt+lv/WzAiV 0MG4HsDoT+5oxg5scbp0LBk37SW7houN+ymVNhSSeN9BTG33faDEL9wpfgXOK6TeVyJM qgGQ== X-Gm-Message-State: APjAAAU7gUDYlO4O2gt5thy10AFiiRgHY2Uxwf51oh8JnBVfGGFGKotp qwnymawJ/nJ4UfsUUzLQYOXoHypF X-Google-Smtp-Source: APXvYqzucoSVikOMLjR9oVn2f0+/hoIKNEcqvVEGT7f01Y4nxrLzRGQn9D5AMNwm4ldVi+WslcRirQ== X-Received: by 2002:a62:14c6:: with SMTP id 189mr8200305pfu.23.1551889884664; Wed, 06 Mar 2019 08:31:24 -0800 (PST) Received: from ?IPv6:2620:15c:2c1:200:55c7:81e6:c7d8:94b? ([2620:15c:2c1:200:55c7:81e6:c7d8:94b]) by smtp.gmail.com with ESMTPSA id y9sm3803099pfn.120.2019.03.06.08.31.23 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 06 Mar 2019 08:31:23 -0800 (PST) Subject: Re: [PATCH] tcp: detecting the misuse of .sendpage for Slab objects To: Vasily Averin , Eric Dumazet , netdev@vger.kernel.org References: <2a77e65a-9d81-9ddb-f7af-b3b6da095a10@virtuozzo.com> From: Eric Dumazet Message-ID: <0651e79d-5dfa-1d2c-6c92-dccc5a9027a7@gmail.com> Date: Wed, 6 Mar 2019 08:31:23 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <2a77e65a-9d81-9ddb-f7af-b3b6da095a10@virtuozzo.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 03/06/2019 03:10 AM, Vasily Averin wrote: > sendpage was not designed for processing of the Slab pages, > in some situations it can trigger BUG_ON on receiving side. > > Signed-off-by: Vasily Averin > --- > net/ipv4/tcp.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index ad07dd71063d..dbb08140cdc9 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -943,6 +943,10 @@ ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, > ssize_t copied; > long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); > > + if (IS_ENABLED(CONFIG_DEBUG_VM) && > + WARN_ONCE(PageSlab(page), "page must not be a Slab one")) > + return -EINVAL; > + > /* Wait for a connection to finish. One exception is TCP Fast Open > * (passive side) where data is allowed to be sent before a connection > * is fully established. > SGTM David, this probably can be merged into net tree. Signed-off-by: Eric Dumazet