From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 0A5FC7494; Fri, 26 Jul 2024 15:02:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722006127; cv=none; b=geyLo97fXmLqFS+RE31Utw1NRT0dMi3me/sBaxG6dGo/deUOzx3ezGHx4buPQpJsKNpBKlBwNxOUCVxJwP0UUyDO6Key6fObnosPMl5i3vsl9vnkZocTM+UQsEvSr1Ov674fAHbvbzir7H28/d+KyCWGSNBhUVWg4hureyy2wxc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722006127; c=relaxed/simple; bh=nVwWTgdTUodovh/iqkzdCNEo1Majgzgo+6kXKdU3h7Y=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=h8zXfz67Y8c3WSekXf7Un5uVdEJjTDT2qG3BYiGbqChm2zqUiPRtTCd98cAf7d4Cb63srqoCfBJRpGwxJdep+doxK9SOcJoPyUy6QzYn5Vd57GMi5vWSTCj6qN3dKiEpwUJCjrUQ1wKK97D+7sXyRJJvvvDCZrH7QrVaydglzuI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=I/WdCJLL; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="I/WdCJLL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2E7E8C32786; Fri, 26 Jul 2024 15:02:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722006126; bh=nVwWTgdTUodovh/iqkzdCNEo1Majgzgo+6kXKdU3h7Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=I/WdCJLLxqzmfyvQnQEfyewqeZdzswsEYRNfxRlINW2IhlKLAslVpSGu6i1NMs2d6 ZwI/sUt6H4mg9IhWfDhSqW+OzsvGwbA5IX8MrXoSexWfvzP1KyNRrJB0mWNAENRG/s jDiUnRr3U8AZuVEfOxQ3/+xAC2wp+l2OahinaAL5PR6UH4kIyLAeztPQwbE/56Ub9U AnPt8pHdWIRJx5ZJvixWNDp6e68NYbB8dshsQG6ojOy915j/t2ik3RV5Vf3fot5B7m 8GcotEEHQaE15bhljCKAynGjVSM1K2nEiGzBDIs9uOr4yHVNqPXqWU6W1s/qE5ePh1 y3efdvC9Sk+Tg== Date: Fri, 26 Jul 2024 08:02:05 -0700 From: Jakub Kicinski To: James Chapman Cc: syzbot , davem@davemloft.net, edumazet@google.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [net?] BUG: unable to handle kernel paging request in net_generic Message-ID: <20240726080205.33661f4e@kernel.org> In-Reply-To: <000000000000f9eeec061e0ffa03@google.com> References: <000000000000f9eeec061e0ffa03@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit CC: James [L2TP] On Thu, 25 Jul 2024 03:37:24 -0700 syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: c912bf709078 Merge remote-tracking branches 'origin/arm64-.. > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > console output: https://syzkaller.appspot.com/x/log.txt?x=1625a15e980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=79a49b0b9ffd6585 > dashboard link: https://syzkaller.appspot.com/bug?extid=6acef9e0a4d1f46c83d4 > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > userspace arch: arm64 > > Unfortunately, I don't have any reproducer for this issue yet. > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/fea69a9d153c/disk-c912bf70.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/be06762a72ef/vmlinux-c912bf70.xz > kernel image: https://storage.googleapis.com/syzbot-assets/6c8e58b4215d/Image-c912bf70.gz.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+6acef9e0a4d1f46c83d4@syzkaller.appspotmail.com > > Unable to handle kernel paging request at virtual address dfff800000000257 > KASAN: probably user-memory-access in range [0x00000000000012b8-0x00000000000012bf] > Mem abort info: > ESR = 0x0000000096000005 > EC = 0x25: DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > FSC = 0x05: level 1 translation fault > Data abort info: > ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 > CM = 0, WnR = 0, TnD = 0, TagAccess = 0 > GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 > [dfff800000000257] address between user and kernel address ranges > Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP > Modules linked in: > CPU: 1 PID: 6969 Comm: syz.2.105 Not tainted 6.10.0-rc7-syzkaller-gc912bf709078 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 > pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : net_generic+0xd0/0x250 include/net/netns/generic.h:46 > lr : rcu_read_lock include/linux/rcupdate.h:782 [inline] > lr : net_generic+0x54/0x250 include/net/netns/generic.h:45 > sp : ffff8000a6c86c10 > x29: ffff8000a6c86c10 x28: dfff800000000000 x27: 0000000000000802 > x26: 0000000000000002 x25: 1ffff00014d90d88 x24: dfff800000000000 > x23: ffff0000ca3fbd70 x22: ffff8000a6c86c40 x21: dfff800000000000 > x20: 00000000000012b8 x19: 000000000000004e x18: 1ffff00014d90cfe > x17: 000000000003099a x16: ffff80008054bde8 x15: 0000000000000001 > x14: ffff80008f100568 x13: dfff800000000000 x12: 00000000af8628cd > x11: 0000000068a0e22d x10: 0000000000ff0100 x9 : 0000000000000000 > x8 : 0000000000000257 x7 : ffff80008a4326a8 x6 : 0000000000000000 > x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000002 > x2 : 0000000000000008 x1 : ffff80008b681f20 x0 : 0000000000000001 > Call trace: > net_generic+0xd0/0x250 include/net/netns/generic.h:46 > l2tp_pernet net/l2tp/l2tp_core.c:125 [inline] > l2tp_tunnel_get+0x90/0x464 net/l2tp/l2tp_core.c:207 > l2tp_udp_recv_core net/l2tp/l2tp_core.c:852 [inline] > l2tp_udp_encap_recv+0x314/0xb3c net/l2tp/l2tp_core.c:933 > udpv6_queue_rcv_one_skb+0x1870/0x1ad4 net/ipv6/udp.c:727 > udpv6_queue_rcv_skb+0x3bc/0x574 net/ipv6/udp.c:789 > udp6_unicast_rcv_skb+0x1cc/0x320 net/ipv6/udp.c:929 > __udp6_lib_rcv+0xbcc/0x1330 net/ipv6/udp.c:1018 > udpv6_rcv+0x88/0x9c net/ipv6/udp.c:1133 > ip6_protocol_deliver_rcu+0x988/0x12a4 net/ipv6/ip6_input.c:438 > ip6_input_finish+0x164/0x298 net/ipv6/ip6_input.c:483 > NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:314 > ip6_input+0x90/0xa8 net/ipv6/ip6_input.c:492 > dst_input include/net/dst.h:460 [inline] > ip6_rcv_finish+0x1f0/0x21c net/ipv6/ip6_input.c:79 > NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:314 > ipv6_rcv+0x9c/0xbc net/ipv6/ip6_input.c:310 > __netif_receive_skb_one_core net/core/dev.c:5625 [inline] > __netif_receive_skb+0x18c/0x3c8 net/core/dev.c:5739 > netif_receive_skb_internal net/core/dev.c:5825 [inline] > netif_receive_skb+0x1f0/0x93c net/core/dev.c:5885 > tun_rx_batched+0x568/0x6e4 > tun_get_user+0x260c/0x3978 drivers/net/tun.c:2002 > tun_chr_write_iter+0xfc/0x204 drivers/net/tun.c:2048 > new_sync_write fs/read_write.c:497 [inline] > vfs_write+0x8f8/0xc38 fs/read_write.c:590 > ksys_write+0x15c/0x26c fs/read_write.c:643 > __do_sys_write fs/read_write.c:655 [inline] > __se_sys_write fs/read_write.c:652 [inline] > __arm64_sys_write+0x7c/0x90 fs/read_write.c:652 > __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] > invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 > el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:131 > do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:150 > el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 > el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 > el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 > Code: d2d00015 f2fbfff5 8b080294 d343fe88 (38756908) > ---[ end trace 0000000000000000 ]--- > ---------------- > Code disassembly (best guess): > 0: d2d00015 mov x21, #0x800000000000 // #140737488355328 > 4: f2fbfff5 movk x21, #0xdfff, lsl #48 > 8: 8b080294 add x20, x20, x8 > c: d343fe88 lsr x8, x20, #3 > * 10: 38756908 ldrb w8, [x8, x21] <-- trapping instruction > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) > > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report > > If you want to undo deduplication, reply with: > #syz undup