From patchwork Sun May 16 14:44:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Taehee Yoo X-Patchwork-Id: 440534 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=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 82083C433B4 for ; Sun, 16 May 2021 14:45:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53B9861182 for ; Sun, 16 May 2021 14:45:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234277AbhEPOqP (ORCPT ); Sun, 16 May 2021 10:46:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230324AbhEPOqO (ORCPT ); Sun, 16 May 2021 10:46:14 -0400 Received: from mail-pj1-x1032.google.com (mail-pj1-x1032.google.com [IPv6:2607:f8b0:4864:20::1032]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CAA7BC061573 for ; Sun, 16 May 2021 07:44:58 -0700 (PDT) Received: by mail-pj1-x1032.google.com with SMTP id g6-20020a17090adac6b029015d1a9a6f1aso3299922pjx.1 for ; Sun, 16 May 2021 07:44:58 -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; bh=z9JsyJfRlzMAJOT7FcT3zfUktNZ2mMjszlvqkw6Wvc4=; b=ZQ2aq/cS22ACEuQbiZG6QbtXly07tJzdP6wGgihJtcAliLr7NI/88QuZZ3re2gQSFw 9+d4Sjbo7nOZ70clmm0DdDGSTfRrZXFSMJLGmVZJ6Qbb5jo8rf1orwP95wbEll5uAKyI 74GYmMTuB+dDASN3FPfPWs30v8eBtPUV0vFxEEzEnG6AT1HKWzd0vPB011kMwIf7kNqY lLnR8FSQ0zLDsRK+Y1vJBdaMLx8R9nE/M/vOde1XU66nv42xk7/pvXI0WgK4Ni6GFlm6 AKsrLiAudevELlWCsektsf/0fMGxcOEMK4MCLG85Z5AnHNOWhR0rn70HInR9+JiAWyQF 7EwQ== 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; bh=z9JsyJfRlzMAJOT7FcT3zfUktNZ2mMjszlvqkw6Wvc4=; b=VumpaY0zgcVwybFqiZs2CN3geA1lsCPLRN4ulNRmnN5H+W8equnAKbN5q7Zofq3rmW bOeY/iovWK4cLnedXaU5SC+E3GzdNWKXMxEnOuz7VWCsQNaXJoperrjscYJfGeTjDAdS Ydg/ukS4JU6TFplIh67MV8HF1IhvyE4KzUDB7BVbw2elxk4aFUH9rYOlUTGwZSJmSzwz NuOLjUU9CETCuMKXgGoKjs/Yf/d3+K+XlwrKIGCYmCo3jgdZEHR3Z9WpL3G0HrSOXhQ0 4k9hHpMh5DGZ9XGNs2FtgJAD3hOTyBofXMiiyoEsCFL9E1U5ETFUtLW146lQnLtmEIdi XGlA== X-Gm-Message-State: AOAM531F8b7qmJBwbYiozjc6NYR6D3WxMMDmb+5XY93rVZ+x033pwXZ2 XVA6EQi3XGVq+VpaVrszz4U= X-Google-Smtp-Source: ABdhPJxXJgrnes8LcIxar521p1bRCTEX14ucsJAPsSqDdV0VPvI2o6v0vssfjLrh7jtvWuU77X2tFg== X-Received: by 2002:a17:90a:a604:: with SMTP id c4mr21782157pjq.81.1621176298213; Sun, 16 May 2021 07:44:58 -0700 (PDT) Received: from localhost.localdomain ([49.173.165.50]) by smtp.gmail.com with ESMTPSA id s9sm5390683pfm.120.2021.05.16.07.44.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 16 May 2021 07:44:57 -0700 (PDT) From: Taehee Yoo To: davem@davemloft.net, kuba@kernel.org, dsahern@kernel.org, yoshfuji@linux-ipv6.org, netdev@vger.kernel.org, eric.dumazet@gmail.com, xiyou.wangcong@gmail.com Cc: ap420073@gmail.com Subject: [PATCH v2 net] mld: fix panic in mld_newpack() Date: Sun, 16 May 2021 14:44:42 +0000 Message-Id: <20210516144442.4838-1-ap420073@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org mld_newpack() doesn't allow to allocate high order page, only order-0 allocation is allowed. If headroom size is too large, a kernel panic could occur in skb_put(). Test commands: ip netns del A ip netns del B ip netns add A ip netns add B ip link add veth0 type veth peer name veth1 ip link set veth0 netns A ip link set veth1 netns B ip netns exec A ip link set lo up ip netns exec A ip link set veth0 up ip netns exec A ip -6 a a 2001:db8:0::1/64 dev veth0 ip netns exec B ip link set lo up ip netns exec B ip link set veth1 up ip netns exec B ip -6 a a 2001:db8:0::2/64 dev veth1 for i in {1..99} do let A=$i-1 ip netns exec A ip link add ip6gre$i type ip6gre \ local 2001:db8:$A::1 remote 2001:db8:$A::2 encaplimit 100 ip netns exec A ip -6 a a 2001:db8:$i::1/64 dev ip6gre$i ip netns exec A ip link set ip6gre$i up ip netns exec B ip link add ip6gre$i type ip6gre \ local 2001:db8:$A::2 remote 2001:db8:$A::1 encaplimit 100 ip netns exec B ip -6 a a 2001:db8:$i::2/64 dev ip6gre$i ip netns exec B ip link set ip6gre$i up done Splat looks like: kernel BUG at net/core/skbuff.c:110! invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.12.0+ #891 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:skb_panic+0x15d/0x15f Code: 92 fe 4c 8b 4c 24 10 53 8b 4d 70 45 89 e0 48 c7 c7 00 ae 79 83 41 57 41 56 41 55 48 8b 54 24 a6 26 f9 ff <0f> 0b 48 8b 6c 24 20 89 34 24 e8 4a 4e 92 fe 8b 34 24 48 c7 c1 20 RSP: 0018:ffff88810091f820 EFLAGS: 00010282 RAX: 0000000000000089 RBX: ffff8881086e9000 RCX: 0000000000000000 RDX: 0000000000000089 RSI: 0000000000000008 RDI: ffffed1020123efb RBP: ffff888005f6eac0 R08: ffffed1022fc0031 R09: ffffed1022fc0031 R10: ffff888117e00187 R11: ffffed1022fc0030 R12: 0000000000000028 R13: ffff888008284eb0 R14: 0000000000000ed8 R15: 0000000000000ec0 FS: 0000000000000000(0000) GS:ffff888117c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8b801c5640 CR3: 0000000033c2c006 CR4: 00000000003706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600 ? ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600 skb_put.cold.104+0x22/0x22 ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600 ? rcu_read_lock_sched_held+0x91/0xc0 mld_newpack+0x398/0x8f0 ? ip6_mc_hdr.isra.26.constprop.46+0x600/0x600 ? lock_contended+0xc40/0xc40 add_grhead.isra.33+0x280/0x380 add_grec+0x5ca/0xff0 ? mld_sendpack+0xf40/0xf40 ? lock_downgrade+0x690/0x690 mld_send_initial_cr.part.34+0xb9/0x180 ipv6_mc_dad_complete+0x15d/0x1b0 addrconf_dad_completed+0x8d2/0xbb0 ? lock_downgrade+0x690/0x690 ? addrconf_rs_timer+0x660/0x660 ? addrconf_dad_work+0x73c/0x10e0 addrconf_dad_work+0x73c/0x10e0 Allowing high order page allocation could fix this problem. Fixes: 72e09ad107e7 ("ipv6: avoid high order allocations") Signed-off-by: Taehee Yoo --- v1 -> v2: - Wait for mld-sleepable patchset to be merged. net/ipv6/mcast.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index 0d59efb6b49e..d36ef9d25e73 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -1745,10 +1745,7 @@ static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu) IPV6_TLV_PADN, 0 }; /* we assume size > sizeof(ra) here */ - /* limit our allocations to order-0 page */ - size = min_t(int, size, SKB_MAX_ORDER(0, 0)); skb = sock_alloc_send_skb(sk, size, 1, &err); - if (!skb) return NULL;