From mboxrd@z Thu Jan 1 00:00:00 1970 From: syzbot Subject: BUG: unable to handle kernel NULL pointer dereference in corrupted Date: Fri, 08 Jun 2018 06:11:02 -0700 Message-ID: <000000000000b98577056e212120@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes To: davem@davemloft.net, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com Return-path: Received: from mail-io0-f199.google.com ([209.85.223.199]:38712 "EHLO mail-io0-f199.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751524AbeFHNLC (ORCPT ); Fri, 8 Jun 2018 09:11:02 -0400 Received: by mail-io0-f199.google.com with SMTP id g22-v6so10060497ioh.5 for ; Fri, 08 Jun 2018 06:11:02 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: Hello, syzbot found the following crash on: HEAD commit: 68abbe729567 Merge branch 'akpm' (patches from Andrew) git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16f7cebf800000 kernel config: https://syzkaller.appspot.com/x/.config?x=e5a4673d4582131c dashboard link: https://syzkaller.appspot.com/bug?extid=f5066e369b2d5fff630f compiler: gcc (GCC) 8.0.1 20180413 (experimental) syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=1191756f800000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162236af800000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+f5066e369b2d5fff630f@syzkaller.appspotmail.com random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 PGD 1b51e5067 P4D 1b51e5067 PUD 1b508f067 PMD 0 Oops: 0010 [#1] SMP KASAN CPU: 1 PID: 4485 Comm: syz-executor452 Not tainted 4.17.0+ #90 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010: (null) Code: Bad RIP value. RSP: 0018:ffff8801b6f273a0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8801b629b800 RCX: 1ffffffff10ea805 RDX: ffff8801b6f27c00 RSI: ffff8801ae67a100 RDI: ffff8801b51feac0 RBP: ffff8801b6f27510 R08: ffff8801b563cf78 R09: 0000000000000006 R10: ffff8801b563c740 R11: 0000000000000000 R12: 1ffff10036de4e79 R13: ffff8801b6f27c00 R14: ffff8801b629b812 R15: ffff8801b629bc58 FS: 0000000001c2b880(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001b5625000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sock_poll+0x1d1/0x710 net/socket.c:1156 vfs_poll+0x77/0x2a0 fs/select.c:40 ep_item_poll.isra.15+0x2c1/0x390 fs/eventpoll.c:887 ep_insert+0x6b8/0x1c00 fs/eventpoll.c:1459 __do_sys_epoll_ctl fs/eventpoll.c:2113 [inline] __se_sys_epoll_ctl fs/eventpoll.c:1999 [inline] __x64_sys_epoll_ctl+0xef1/0x10f0 fs/eventpoll.c:1999 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x43fcc9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 6b 45 00 00 c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff59e3a2f8 EFLAGS: 00000217 ORIG_RAX: 00000000000000e9 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fcc9 RDX: 0000000000000003 RSI: 0000000000000001 RDI: 0000000000000004 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 0000000020000000 R11: 0000000000000217 R12: 00000000004015f0 R13: 0000000000401680 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: Dumping ftrace buffer: (ftrace buffer empty) CR2: 0000000000000000 ---[ end trace 090a30b2125a99a3 ]--- RIP: 0010: (null) Code: Bad RIP value. RSP: 0018:ffff8801b6f273a0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8801b629b800 RCX: 1ffffffff10ea805 RDX: ffff8801b6f27c00 RSI: ffff8801ae67a100 RDI: ffff8801b51feac0 RBP: ffff8801b6f27510 R08: ffff8801b563cf78 R09: 0000000000000006 R10: ffff8801b563c740 R11: 0000000000000000 R12: 1ffff10036de4e79 R13: ffff8801b6f27c00 R14: ffff8801b629b812 R15: ffff8801b629bc58 FS: 0000000001c2b880(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001b5625000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 --- 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#bug-status-tracking for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches