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=-15.8 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,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 51480C4338F for ; Sat, 21 Aug 2021 07:14:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 30B9361101 for ; Sat, 21 Aug 2021 07:14:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232838AbhHUHPY (ORCPT ); Sat, 21 Aug 2021 03:15:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231738AbhHUHPV (ORCPT ); Sat, 21 Aug 2021 03:15:21 -0400 Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4EFBC061575; Sat, 21 Aug 2021 00:14:42 -0700 (PDT) Received: by mail-pj1-x102d.google.com with SMTP id fa24-20020a17090af0d8b0290178bfa69d97so8854315pjb.0; Sat, 21 Aug 2021 00:14:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=d64sHr5B5Q8l4jh+HMlfEo+7I1B8zRJJdtRpfTb8yTE=; b=OxgELvsvTZVoJqFsJ0aQI36b1FlaOxfZDaPPcGK25dxmRlIbbyfX8IODEWa9zdMzUs gjy0I9lSD9AKjmYD8Nh/RAqiuDGZ7L5/9EQnzbPWYGskritjL2JXMT4XlZQuz5QIb0Zk //4q6Sdm21dUiztHiNP35NgxnolaRRBQFIC2ruYWZeCIKj3EA+35ce27qRFiTEdGinqr AWv6UG95GHB59kvQYu/mWoYknBT9T9JrSbkHEiYTgaQgmLxirc2elpT8tbsqyK5QuxNc cjwCDm1sVULtm9T+6Pl9+c7f8yuXj6qI72gGn+ySOrBs+GnanhwdM9hws2B2KYTdxm1I vgKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=d64sHr5B5Q8l4jh+HMlfEo+7I1B8zRJJdtRpfTb8yTE=; b=ZNlNwMkS6u/ggCupNQnTE9TTlrmWusUjlLN+eMgzeXGcbtTX8RQQoWWLHQegO4FFv8 S+MtSYKOPprTPZsRdsj/muLsA0BKXT2pr0TxBwCO7jH8GjpukyoqO2aNJs3XoZTrPXpJ Ykc0/lDjLor1yG647KjHh2jCqLp8EIHPg+7NPs6SSQapJim8vizoS450pHWXBQ5jw0J7 IXDtmJSVNNyh9C8JlHmjxiCNHuso8KGV0kTAkxsAgKPsi6Zx3inl4r6w0EUNMwAZJ63j gkZKtuosVfFTEr7hctT0TWXpKhDJT/OgKurcwKikSlJKEaQe1GSsAXdgQGs52RfWRIv0 UaQQ== X-Gm-Message-State: AOAM531WaQzowFNsC2P24PnhlEGB7tkM8EVEDOUXGHXa1pVirpuOT3tV 4b26cwL96JdVfGEopYP+UEQ= X-Google-Smtp-Source: ABdhPJxumDzpnaUtwpVrde/2JIooqvWXtjXYqslScKiNGDjI7R0DlJKzBTJXWe6sS8OD/PXWjIMePw== X-Received: by 2002:a17:902:c10a:b0:12d:97e1:f035 with SMTP id 10-20020a170902c10a00b0012d97e1f035mr19775570pli.52.1629530082300; Sat, 21 Aug 2021 00:14:42 -0700 (PDT) Received: from fedora.. ([2405:201:6008:6ce2:9fb0:9db:90a4:39e2]) by smtp.googlemail.com with ESMTPSA id c7sm6901973pjc.31.2021.08.21.00.14.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 21 Aug 2021 00:14:41 -0700 (PDT) From: Shreyansh Chouhan To: davem@davemloft.net, yoshfuji@linux-ipv6.org, dsahern@kernel.org, kuba@kernel.org, pshelar@nicira.com, willemdebruijn.kernel@gmail.com Cc: Shreyansh Chouhan , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+ff8e1b9f2f36481e2efc@syzkaller.appspotmail.com Subject: [PATCH 1/2 net] ip_gre: add validation for csum_start Date: Sat, 21 Aug 2021 12:44:24 +0530 Message-Id: <20210821071425.512834-1-chouhan.shreyansh630@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210819100447.00201b26@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> References: <20210819100447.00201b26@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Validate csum_start in gre_handle_offloads before we call _gre_xmit so that we do not crash later when the csum_start value is used in the lco_csum function call. This patch deals with ipv4 code. Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.") Reported-by: syzbot+ff8e1b9f2f36481e2efc@syzkaller.appspotmail.com Signed-off-by: Shreyansh Chouhan --- net/ipv4/ip_gre.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 12dca0c85f3c..95419b7adf5c 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -473,6 +473,8 @@ static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, static int gre_handle_offloads(struct sk_buff *skb, bool csum) { + if (csum && skb_checksum_start(skb) < skb->data) + return -EINVAL; return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); } -- 2.31.1