From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga04-in.huawei.com (szxga04-in.huawei.com [45.249.212.190]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E85C4A1A; Thu, 27 Mar 2025 07:40:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.190 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743061213; cv=none; b=T6+oM0ZEERCpT1uLBS343Zq18OiCk+epozLjgrr7/CMNSzhPqyP3q0pO6PGOtnSIYSGl1QckP1nVhFO7g8O04/t+FxutRLKLdiQo2JCPTscy2yLyWZNzTkeBrF+OzqhGWCIv6DWsiqkeEJrLBmr4h+yycosotsqBG/RZDJ9tQzY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743061213; c=relaxed/simple; bh=xIzDxi++J3dCaLpdaxTc+W8/qa00RPqhhzN6FtJfE20=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=pY/FyQ7Tl2MYERCibOJiAb9OFv7KcKkl1Mq4fvx7HSaI2kLdXPMkseFKFpTKo7Hy0AkC5MmuEmc0VCMHjIKOFivjC7ERKVui3+1l7KQ6esNJQwWrOqJfz8itpWowgl+KJsaJlYTfOACIlF12U8AMjBZ5AZDbxK6wwqzVN7uj9Zs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.190 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4ZNb6R2k9Gz2TS0C; Thu, 27 Mar 2025 15:35:27 +0800 (CST) Received: from kwepemg200005.china.huawei.com (unknown [7.202.181.32]) by mail.maildlp.com (Postfix) with ESMTPS id DEFF71A016C; Thu, 27 Mar 2025 15:40:07 +0800 (CST) Received: from [10.174.176.70] (10.174.176.70) by kwepemg200005.china.huawei.com (7.202.181.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Thu, 27 Mar 2025 15:40:06 +0800 Message-ID: <7b0e4957-623b-45ce-85e4-e4c08cbdb8b3@huawei.com> Date: Thu, 27 Mar 2025 15:40:06 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net] ipv6: sit: fix skb_under_panic with overflowed needed_headroom To: Eric Dumazet CC: , , , , , , , , , References: <20250327015827.2729554-1-wangliang74@huawei.com> From: Wang Liang In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemg200005.china.huawei.com (7.202.181.32) 在 2025/3/27 14:39, Eric Dumazet 写道: > On Thu, Mar 27, 2025 at 7:33 AM Wang Liang wrote: >> >> >> You can get the report in >> https://syzkaller.appspot.com/text?tag=CrashReport&x=106b6b34880000 > Well, please provide the most accurate stack trace with symbols in > your patch then ? > > If you spent time reproducing the issue and providing your stack > trace, please add the symbols. Thank you for the reminder of decode_stacktrace.sh. I just reproduce the issue, and first use decode_stacktrace.sh to get the stack trace below[1], please check it. I will update the stack trace in my patch later. Thanks. [1] [  895.885034][T23587] ------------[ cut here ]------------ [  895.885951][T23587] kernel BUG at net/core/skbuff.c:209! [  895.886889][T23587] Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI [  895.888037][T23587] CPU: 0 UID: 0 PID: 23587 Comm: test Tainted: G        W          6.14.0-00624-g2f2d52945852-dirty #15 [  895.889837][T23587] Tainted: [W]=WARN [  895.890469][T23587] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 [895.891962][T23587] RIP: 0010:skb_panic (net/core/skbuff.c:209 (discriminator 4)) [ 895.892786][T23587] Code: 0f b6 04 01 84 c0 74 04 3c 03 7e 20 8b 4b 70 41 56 45 89 e8 48 c7 c7 c0 0c 7e 8b 41 57 56 48 89 ee 52 4c 89 e2 e8 6a 40 6e f9 <0f> 0b 4c 89 4c 24 10 48 89 54 24 08 48 89 34 24 e8 b5 68 ec f9 4c [  895.895918][T23587] RSP: 0018:ffffc900000e6a18 EFLAGS: 00010282 [  895.897396][T23587] RAX: 0000000000000088 RBX: ffff88809a0cd000 RCX: ffffffff819352e9 [  895.898695][T23587] RDX: 0000000000000000 RSI: ffffffff8193bd1d RDI: 0000000000000005 [  895.899992][T23587] RBP: ffffffff8b7e2020 R08: 0000000000000000 R09: fffffbfff1989a84 [  895.901274][T23587] R10: 0000000000000200 R11: 000000000023df70 R12: ffffffff88d9b291 [  895.902561][T23587] R13: 0000000000000008 R14: ffff88805013e120 R15: 0000000000000180 [  895.903863][T23587] FS:  00000000162863c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 [  895.905307][T23587] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [  895.906378][T23587] CR2: ffffffffff600400 CR3: 0000000094fcc000 CR4: 00000000000006f0 [  895.907669][T23587] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [  895.908960][T23587] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [  895.910252][T23587] Call Trace: [  895.910798][T23587]  [895.923567][T23587] skb_push (net/core/skbuff.c:2544) [895.924232][T23587] fou_build_udp (./include/linux/skbuff.h:3026 net/ipv4/fou_core.c:1041) [895.925001][T23587] gue_build_header (net/ipv4/fou_core.c:1085) [895.927586][T23587] ip_tunnel_xmit (./include/net/ip_tunnels.h:541 ./include/net/ip_tunnels.h:525 net/ipv4/ip_tunnel.c:780) [895.931769][T23587] sit_tunnel_xmit__.isra.0 (net/ipv6/sit.c:1065) [895.932682][T23587] sit_tunnel_xmit (net/ipv6/sit.c:1076) [895.937147][T23587] dev_hard_start_xmit (./include/linux/netdevice.h:5161 net/core/dev.c:3800 net/core/dev.c:3816) [895.937996][T23587] __dev_queue_xmit (net/core/dev.h:320 net/core/dev.c:4653) [895.945680][T23587] neigh_connected_output (./include/linux/netdevice.h:3313 net/core/neighbour.c:1543) [895.946570][T23587] ip_finish_output2 (./include/net/neighbour.h:539 net/ipv4/ip_output.c:236) [895.948304][T23587] __ip_finish_output (net/ipv4/ip_output.c:314 net/ipv4/ip_output.c:296) [895.949152][T23587] ip_finish_output (net/ipv4/ip_output.c:324) [895.949945][T23587] ip_mc_output (./include/linux/netfilter.h:303 net/ipv4/ip_output.c:421) [895.951538][T23587] ip_send_skb (./include/net/dst.h:459 ./include/net/dst.h:457 net/ipv4/ip_output.c:130 net/ipv4/ip_output.c:1502) [895.952279][T23587] udp_send_skb (net/ipv4/udp.c:1197) [895.953048][T23587] udp_sendmsg (net/ipv4/udp.c:1484) [895.962452][T23587] udpv6_sendmsg (net/ipv6/udp.c:1545 (discriminator 1)) [895.976909][T23587] inet6_sendmsg (net/ipv6/af_inet6.c:659 (discriminator 4)) [895.978530][T23587] ____sys_sendmsg (net/socket.c:718 net/socket.c:733 net/socket.c:2573) [895.982832][T23587] ___sys_sendmsg (net/socket.c:2629) [895.988814][T23587] __sys_sendmmsg (net/socket.c:2719) [895.994530][T23587] __x64_sys_sendmmsg (net/socket.c:2740) [895.996217][T23587] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) [895.996965][T23587] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) [  895.997937][T23587] RIP: 0033:0x44a19d [ 895.998581][T23587] Code: c3 e8 37 1f 00 00 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 [  896.001683][T23587] RSP: 002b:00007fffc1b01a88 EFLAGS: 00000216 ORIG_RAX: 0000000000000133 [  896.003032][T23587] RAX: ffffffffffffffda RBX: 0000000020000014 RCX: 000000000044a19d [  896.004311][T23587] RDX: 0000000000000001 RSI: 00000000200017c0 RDI: 0000000000000003 [  896.005595][T23587] RBP: 00007fffc1b01ab0 R08: 0000000000000000 R09: 0000000000000000 [  896.006891][T23587] R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000000001 [  896.008164][T23587] R13: 00007fffc1b01cf8 R14: 00000000004c4710 R15: 0000000000000001 [  896.009454][T23587]  [  896.009969][T23587] Modules linked in: [  896.010664][T23587] ---[ end trace 0000000000000000 ]---