From patchwork Thu Sep 27 07:15:33 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Liu X-Patchwork-Id: 975570 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.b="KyniX0Z1"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42LR123Qytz9s3l for ; Thu, 27 Sep 2018 17:15:50 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726790AbeI0Ncf (ORCPT ); Thu, 27 Sep 2018 09:32:35 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:44882 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726681AbeI0Ncf (ORCPT ); Thu, 27 Sep 2018 09:32:35 -0400 Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w8R7F4n3022169 for ; Thu, 27 Sep 2018 00:15:46 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=facebook; bh=gTZhxN6p/OpkmOm9GqnLoTsJfHrCE6R5RMqn3O5W0Fk=; b=KyniX0Z1U20P1qagWyCLvDtlvOzbYudkzBdOBDdM+0F7ExQn7a3j0P0asjy8WyLvCPZn 3BPjjSIyZOtcFmNAL9xI+BhfBe10pITiKXIjuPU5NbD3d9gBzhgsWNW6VQltoKTYvUz8 Zdkaka8MHzds/3CAwuJyOtWFCWoF43rYlNA= Received: from mail.thefacebook.com ([199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2mrsavg63s-3 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Thu, 27 Sep 2018 00:15:46 -0700 Received: from mx-out.facebook.com (192.168.52.123) by mail.thefacebook.com (192.168.16.22) with Microsoft SMTP Server (TLS) id 14.3.319.2; Thu, 27 Sep 2018 00:15:46 -0700 Received: by devbig006.ftw2.facebook.com (Postfix, from userid 4523) id 677B662E1CD9; Thu, 27 Sep 2018 00:15:43 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Song Liu Smtp-Origin-Hostname: devbig006.ftw2.facebook.com To: CC: , , Song Liu , Willem de Bruijn , Petar Penkov Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH bpf-next] bpf: test_bpf: add dummy dev->net for flow_dissector Date: Thu, 27 Sep 2018 00:15:33 -0700 Message-ID: <20180927071533.2290229-1-songliubraving@fb.com> X-Mailer: git-send-email 2.17.1 X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-09-27_04:, , signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Latest changes in __skb_flow_dissect() assume skb->dev has valid nd_net. However, this is not true for test_bpf. As a result, test_bpf.ko crashes the system with the following stack trace: [ 1133.716622] BUG: unable to handle kernel paging request at 0000000000001030 [ 1133.716623] PGD 8000001fbf7ee067 [ 1133.716624] P4D 8000001fbf7ee067 [ 1133.716624] PUD 1f6c1cf067 [ 1133.716625] PMD 0 [ 1133.716628] Oops: 0000 [#1] SMP PTI [ 1133.716630] CPU: 7 PID: 40473 Comm: modprobe Kdump: loaded Not tainted 4.19.0-rc5-00805-gca11cc92ccd2 #1167 [ 1133.716631] Hardware name: Wiwynn Leopard-Orv2/Leopard-DDR BW, BIOS LBM12.5 12/06/2017 [ 1133.716638] RIP: 0010:__skb_flow_dissect+0x83/0x1680 [ 1133.716639] Code: 04 00 00 41 0f b7 44 24 04 48 85 db 4d 8d 14 07 0f 84 01 02 00 00 48 8b 43 10 48 85 c0 0f 84 e5 01 00 00 48 8b 80 a8 04 00 00 <48> 8b 90 30 10 00 00 48 85 d2 0f 84 dd 01 00 00 31 c0 b9 05 00 00 [ 1133.716640] RSP: 0018:ffffc900303c7a80 EFLAGS: 00010282 [ 1133.716642] RAX: 0000000000000000 RBX: ffff881fea0b7400 RCX: 0000000000000000 [ 1133.716643] RDX: ffffc900303c7bb4 RSI: ffffffff8235c3e0 RDI: ffff881fea0b7400 [ 1133.716643] RBP: ffffc900303c7b80 R08: 0000000000000000 R09: 000000000000000e [ 1133.716644] R10: ffffc900303c7bb4 R11: ffff881fb6840400 R12: ffffffff8235c3e0 [ 1133.716645] R13: 0000000000000008 R14: 000000000000001e R15: ffffc900303c7bb4 [ 1133.716646] FS: 00007f54e75d3740(0000) GS:ffff881fff5c0000(0000) knlGS:0000000000000000 [ 1133.716648] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1133.716649] CR2: 0000000000001030 CR3: 0000001f6c226005 CR4: 00000000003606e0 [ 1133.716649] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1133.716650] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1133.716651] Call Trace: [ 1133.716660] ? sched_clock_cpu+0xc/0xa0 [ 1133.716662] ? sched_clock_cpu+0xc/0xa0 [ 1133.716665] ? log_store+0x1b5/0x260 [ 1133.716667] ? up+0x12/0x60 [ 1133.716669] ? skb_get_poff+0x4b/0xa0 [ 1133.716674] ? __kmalloc_reserve.isra.47+0x2e/0x80 [ 1133.716675] skb_get_poff+0x4b/0xa0 [ 1133.716680] bpf_skb_get_pay_offset+0xa/0x10 [ 1133.716686] ? test_bpf_init+0x578/0x1000 [test_bpf] [ 1133.716690] ? netlink_broadcast_filtered+0x153/0x3d0 [ 1133.716695] ? free_pcppages_bulk+0x324/0x600 [ 1133.716696] ? 0xffffffffa0279000 [ 1133.716699] ? do_one_initcall+0x46/0x1bd [ 1133.716704] ? kmem_cache_alloc_trace+0x144/0x1a0 [ 1133.716709] ? do_init_module+0x5b/0x209 [ 1133.716712] ? load_module+0x2136/0x25d0 [ 1133.716715] ? __do_sys_finit_module+0xba/0xe0 [ 1133.716717] ? __do_sys_finit_module+0xba/0xe0 [ 1133.716719] ? do_syscall_64+0x48/0x100 [ 1133.716724] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 This patch fixes tes_bpf by adding a dummy struct net to the dummy dev. Fixes: d0e13a1488ad ("flow_dissector: lookup netns by skb->sk if skb->dev is NULL") Fixes: d58e468b1112 ("flow_dissector: implements flow dissector BPF hook") Cc: Willem de Bruijn Cc: Petar Penkov Signed-off-by: Song Liu Reported-by: Eric Dumazet --- lib/test_bpf.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/lib/test_bpf.c b/lib/test_bpf.c index 08d3d59dca17..5e29d4bd06c8 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -6470,6 +6470,7 @@ static struct bpf_test tests[] = { }, }; +static struct net net; static struct net_device dev; static struct sk_buff *populate_skb(char *buf, int size) @@ -6494,6 +6495,8 @@ static struct sk_buff *populate_skb(char *buf, int size) skb->queue_mapping = SKB_QUEUE_MAP; skb->vlan_tci = SKB_VLAN_TCI; skb->vlan_proto = htons(ETH_P_IP); + dev_net_set(&dev, &net); + RCU_INIT_POINTER(net.flow_dissector_prog, NULL); skb->dev = &dev; skb->dev->ifindex = SKB_DEV_IFINDEX; skb->dev->type = SKB_DEV_TYPE;