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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 6BC9DC38A29 for ; Wed, 15 Apr 2020 12:06:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 553C0206A2 for ; Wed, 15 Apr 2020 12:06:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S368431AbgDOMGf (ORCPT ); Wed, 15 Apr 2020 08:06:35 -0400 Received: from www62.your-server.de ([213.133.104.62]:38598 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2897977AbgDOL56 (ORCPT ); Wed, 15 Apr 2020 07:57:58 -0400 Received: from sslproxy06.your-server.de ([78.46.172.3]) by www62.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1jOgfw-0005x1-GK; Wed, 15 Apr 2020 13:57:52 +0200 Received: from [178.195.186.98] (helo=pc-9.home) by sslproxy06.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jOgfw-000WfK-2j; Wed, 15 Apr 2020 13:57:52 +0200 Subject: Re: WARNING in bpf_cgroup_link_release To: syzbot , andriin@fb.com, ast@kernel.org, bpf@vger.kernel.org, john.fastabend@gmail.com, kafai@fb.com, kpsingh@chromium.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, songliubraving@fb.com, syzkaller-bugs@googlegroups.com, yhs@fb.com References: <000000000000500e6f05a34ecc01@google.com> From: Daniel Borkmann Message-ID: <4ba5ee0c-ec81-8ce3-6681-465e34b98a93@iogearbox.net> Date: Wed, 15 Apr 2020 13:57:51 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <000000000000500e6f05a34ecc01@google.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.102.2/25782/Tue Apr 14 13:57:42 2020) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/15/20 8:55 AM, syzbot wrote: > Hello, > > syzbot found the following crash on: Andrii, ptal. > HEAD commit: 1a323ea5 x86: get rid of 'errret' argument to __get_user_x.. > git tree: bpf-next > console output: https://syzkaller.appspot.com/x/log.txt?x=148ccb57e00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=8c1e98458335a7d1 > dashboard link: https://syzkaller.appspot.com/bug?extid=8a5dadc5c0b1d7055945 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > > Unfortunately, I don't have any reproducer for this crash yet. > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+8a5dadc5c0b1d7055945@syzkaller.appspotmail.com > > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 25081 at kernel/bpf/cgroup.c:796 bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796 > Kernel panic - not syncing: panic_on_warn set ... > CPU: 0 PID: 25081 Comm: syz-executor.1 Not tainted 5.6.0-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x188/0x20d lib/dump_stack.c:118 > panic+0x2e3/0x75c kernel/panic.c:221 > __warn.cold+0x2f/0x35 kernel/panic.c:582 > report_bug+0x27b/0x2f0 lib/bug.c:195 > fixup_bug arch/x86/kernel/traps.c:175 [inline] > fixup_bug arch/x86/kernel/traps.c:170 [inline] > do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267 > do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286 > invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 > RIP: 0010:bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796 > Code: cf ff 5b 5d 41 5c e9 df 2a e9 ff e8 da 2a e9 ff 48 c7 c7 20 f4 9d 89 e8 de a0 3a 06 5b 5d 41 5c e9 c5 2a e9 ff e8 c0 2a e9 ff <0f> 0b e9 57 fe ff ff e8 a4 3d 26 00 e9 2a fe ff ff e8 9a 3d 26 00 > RSP: 0018:ffffc900019a7dc0 EFLAGS: 00010246 > RAX: 0000000000040000 RBX: ffff88808c3eac00 RCX: ffffc9000415a000 > RDX: 0000000000040000 RSI: ffffffff8189bea0 RDI: 0000000000000005 > RBP: 00000000fffffff4 R08: ffff88809055e000 R09: ffffed1015cc70f4 > R10: ffffed1015cc70f3 R11: ffff8880ae63879b R12: ffff88808c3eac60 > R13: ffff88808c3eac10 R14: ffffc90000f32000 R15: ffffffff817f8e60 > bpf_link_free+0x80/0x140 kernel/bpf/syscall.c:2217 > bpf_link_put+0x15e/0x1b0 kernel/bpf/syscall.c:2243 > bpf_link_release+0x33/0x40 kernel/bpf/syscall.c:2251 > __fput+0x2e9/0x860 fs/file_table.c:280 > task_work_run+0xf4/0x1b0 kernel/task_work.c:123 > tracehook_notify_resume include/linux/tracehook.h:188 [inline] > exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165 > prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] > syscall_return_slowpath arch/x86/entry/common.c:279 [inline] > do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305 > entry_SYSCALL_64_after_hwframe+0x49/0xb3 > RIP: 0033:0x45c889 > Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007fddaf43fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 > RAX: 0000000000000000 RBX: 00007fddaf4406d4 RCX: 000000000045c889 > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 > RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 > R13: 0000000000000078 R14: 00000000005043d2 R15: 0000000000000000 > Kernel Offset: disabled > Rebooting in 86400 seconds.. > > > --- > This bug 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 bug report. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. >