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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 101E8CA9EA0 for ; Fri, 25 Oct 2019 13:42:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D914E20679 for ; Fri, 25 Oct 2019 13:42:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=metanetworks.com header.i=@metanetworks.com header.b="Li6TPKlS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2504886AbfJYNmt (ORCPT ); Fri, 25 Oct 2019 09:42:49 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:36495 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2504875AbfJYNms (ORCPT ); Fri, 25 Oct 2019 09:42:48 -0400 Received: by mail-wr1-f65.google.com with SMTP id w18so2419697wrt.3 for ; Fri, 25 Oct 2019 06:42:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=metanetworks.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=0mnmJjgSlbBJ30kBXAxihFKleD83aqV+FTUAUtrG3yA=; b=Li6TPKlS1dN7+hG4fVg7M1mBLXyZSf07oSkHnNQubaNALerMXZKLDxK7R9u+lzqxCy ogprTCWDbICgJw0yomR4qlKWK64bTcZ7INGxfNig4hcYRHNrTzDv69+wbwZzcR6lhuf7 fyzfxPa1PjHRBK+jFpQ/Gv7TKnU4DXkigWg+0= 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; bh=0mnmJjgSlbBJ30kBXAxihFKleD83aqV+FTUAUtrG3yA=; b=M6LCuu4+TbVfrD4uDkQ9fH4476dSmsjBiiQEMg3Ujp/nBf7nGGZ6jQoUcViG41dkzz h43KeuwYvdFBriRrbV3uMt2bKqmK1fXK4QD79NNqyUNexgmxC/OBz1fj2Zrxlea6Coes GHwddQoNlaKfPdmsALN3/pv/lS2QZ/r0i1E/gGNZktBJhI0IcubEjtrCHLZwqguletxY QqgOhrYl/i5GAIqHMMbKGi5LvIRKZ/t8e5fkWFooySapidIO6PNX9er1YrCpcsXUbvFu +pit1Ngco8wrLIh/GQH/ORhQROM3TnSRJekryOQsptLI8zpZRxV9aXVXRDOttlsdp8AR TXjw== X-Gm-Message-State: APjAAAX61D9/JaikMBjjKtye1t61ictCt0HGuKpXq6sN/86ha9Yp6orX ktcMRPZi9VhOv1LWfysqC84Nxw== X-Google-Smtp-Source: APXvYqwupdv7Fh2oROTvgM21NgJagri/TBE8LfHiqS9h+SXH5+3S+USNhdGzYSHXAQdz0PZWE1FJkQ== X-Received: by 2002:adf:e585:: with SMTP id l5mr3085728wrm.156.1572010966360; Fri, 25 Oct 2019 06:42:46 -0700 (PDT) Received: from localhost.localdomain ([94.230.83.169]) by smtp.gmail.com with ESMTPSA id v11sm2194730wrw.97.2019.10.25.06.42.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 25 Oct 2019 06:42:45 -0700 (PDT) From: Shmulik Ladkani X-Google-Original-From: Shmulik Ladkani To: Daniel Borkmann Cc: bpf@vger.kernel.org, netdev@vger.kernel.org, Shmulik Ladkani Subject: [PATCH bpf-next 2/2] test_bpf: Introduce 'gso_linear_no_head_frag' skb_segment test Date: Fri, 25 Oct 2019 16:42:23 +0300 Message-Id: <20191025134223.2761-3-shmulik.ladkani@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191025134223.2761-1-shmulik.ladkani@gmail.com> References: <20191025134223.2761-1-shmulik.ladkani@gmail.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Following reports of skb_segment() hitting a BUG_ON when working on GROed skbs which have their gso_size mangled (e.g. after a bpf_skb_change_proto call), add a reproducer test that mimics the input skbs that lead to the mentioned BUG_ON as in [1] and validates the fix submitted in [2]. [1] https://lists.openwall.net/netdev/2019/08/26/110 [2] commit 3dcbdb134f32 ("net: gso: Fix skb_segment splat when splitting gso_size mangled skb having linear-headed frag_list") Signed-off-by: Shmulik Ladkani --- lib/test_bpf.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) diff --git a/lib/test_bpf.c b/lib/test_bpf.c index c952df82b515..cecb230833be 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -6859,6 +6859,60 @@ static __init struct sk_buff *build_test_skb(void) return NULL; } +static __init struct sk_buff *build_test_skb_linear_no_head_frag(void) +{ + unsigned int alloc_size = 2000; + unsigned int headroom = 102, doffset = 72, data_size = 1308; + struct sk_buff *skb[2]; + int i; + + /* skbs linked in a frag_list, both with linear data, with head_frag=0 + * (data allocated by kmalloc), both have tcp data of 1308 bytes + * (total payload is 2616 bytes). + * Data offset is 72 bytes (40 ipv6 hdr, 32 tcp hdr). Some headroom. + */ + for (i = 0; i < 2; i++) { + skb[i] = alloc_skb(alloc_size, GFP_KERNEL); + if (!skb[i]) { + if (i == 0) + goto err_skb0; + else + goto err_skb1; + } + + skb[i]->protocol = htons(ETH_P_IPV6); + skb_reserve(skb[i], headroom); + skb_put(skb[i], doffset + data_size); + skb_reset_network_header(skb[i]); + if (i == 0) + skb_reset_mac_header(skb[i]); + else + skb_set_mac_header(skb[i], -ETH_HLEN); + __skb_pull(skb[i], doffset); + } + + /* setup shinfo. + * mimic bpf_skb_proto_4_to_6, which resets gso_segs and assigns a + * reduced gso_size. + */ + skb_shinfo(skb[0])->gso_size = 1288; + skb_shinfo(skb[0])->gso_type = SKB_GSO_TCPV6 | SKB_GSO_DODGY; + skb_shinfo(skb[0])->gso_segs = 0; + skb_shinfo(skb[0])->frag_list = skb[1]; + + /* adjust skb[0]'s len */ + skb[0]->len += skb[1]->len; + skb[0]->data_len += skb[1]->len; + skb[0]->truesize += skb[1]->truesize; + + return skb[0]; + +err_skb1: + kfree_skb(skb[0]); +err_skb0: + return NULL; +} + struct skb_segment_test { const char *descr; struct sk_buff *(*build_skb)(void); @@ -6871,6 +6925,15 @@ static struct skb_segment_test skb_segment_tests[] __initconst = { .build_skb = build_test_skb, .features = NETIF_F_SG | NETIF_F_GSO_PARTIAL | NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM + }, + { + .descr = "gso_linear_no_head_frag", + .build_skb = build_test_skb_linear_no_head_frag, + .features = NETIF_F_SG | NETIF_F_FRAGLIST | + NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_GSO | + NETIF_F_LLTX_BIT | NETIF_F_GRO | + NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM | + NETIF_F_HW_VLAN_STAG_TX_BIT } }; -- 2.17.1