[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 39.176255][ T26] audit: type=1800 audit(1555328476.907:25): pid=7721 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 39.213427][ T26] audit: type=1800 audit(1555328476.907:26): pid=7721 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 39.246163][ T26] audit: type=1800 audit(1555328476.907:27): pid=7721 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.37' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 50.753576][ T7872] WARNING: CPU: 1 PID: 7872 at include/linux/cpumask.h:121 io_uring_setup+0x13cd/0x1a30 [ 50.763329][ T7872] Kernel panic - not syncing: panic_on_warn set ... [ 50.769914][ T7872] CPU: 1 PID: 7872 Comm: syz-executor435 Not tainted 5.1.0-rc5 #68 [ 50.777806][ T7872] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.787853][ T7872] Call Trace: [ 50.791131][ T7872] dump_stack+0x172/0x1f0 [ 50.795494][ T7872] ? io_uring_setup+0x1390/0x1a30 [ 50.800549][ T7872] panic+0x2cb/0x65c [ 50.804447][ T7872] ? __warn_printk+0xf3/0xf3 [ 50.809054][ T7872] ? io_uring_setup+0x13cd/0x1a30 [ 50.814083][ T7872] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 50.820325][ T7872] ? __warn.cold+0x5/0x45 [ 50.824662][ T7872] ? __warn+0xe8/0x1d0 [ 50.828732][ T7872] ? io_uring_setup+0x13cd/0x1a30 [ 50.833746][ T7872] __warn.cold+0x20/0x45 [ 50.837972][ T7872] ? io_uring_setup+0x13cd/0x1a30 [ 50.842977][ T7872] report_bug+0x263/0x2b0 [ 50.847294][ T7872] do_error_trap+0x11b/0x200 [ 50.851880][ T7872] do_invalid_op+0x37/0x50 [ 50.856277][ T7872] ? io_uring_setup+0x13cd/0x1a30 [ 50.861301][ T7872] invalid_op+0x14/0x20 [ 50.865446][ T7872] RIP: 0010:io_uring_setup+0x13cd/0x1a30 [ 50.871092][ T7872] Code: 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 84 18 fe ff ff 48 8b bd e8 fe ff ff e8 2d 80 e0 ff e9 07 fe ff ff e8 73 70 a8 ff <0f> 0b e9 bc f8 ff ff e8 67 70 a8 ff 49 8d 84 24 88 00 00 00 48 89 [ 50.890706][ T7872] RSP: 0018:ffff8880a7a47db0 EFLAGS: 00010293 [ 50.896850][ T7872] RAX: ffff888097e7a540 RBX: 00000000fffffffe RCX: ffffffff81c814f7 [ 50.904810][ T7872] RDX: 0000000000000000 RSI: ffffffff81c81c3d RDI: 0000000000000005 [ 50.912791][ T7872] RBP: ffff8880a7a47ee0 R08: ffff888097e7a540 R09: ffffed101182d304 [ 50.920769][ T7872] R10: ffffed101182d303 R11: ffff88808c16981f R12: ffff88808c70b700 [ 50.928733][ T7872] R13: ffff8880a7a47eb8 R14: ffff88808c70b790 R15: ffff88808c70b754 [ 50.936709][ T7872] ? io_uring_setup+0xc87/0x1a30 [ 50.941635][ T7872] ? io_uring_setup+0x13cd/0x1a30 [ 50.946655][ T7872] ? io_uring_release+0x50/0x50 [ 50.951490][ T7872] ? lock_downgrade+0x880/0x880 [ 50.956334][ T7872] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 50.961778][ T7872] ? do_fast_syscall_32+0xd1/0xc98 [ 50.966895][ T7872] ? entry_SYSENTER_compat+0x70/0x7f [ 50.972166][ T7872] ? do_fast_syscall_32+0xd1/0xc98 [ 50.977284][ T7872] ? lockdep_hardirqs_on+0x418/0x5d0 [ 50.982557][ T7872] __ia32_sys_io_uring_setup+0x53/0x70 [ 50.988012][ T7872] do_fast_syscall_32+0x281/0xc98 [ 50.993040][ T7872] entry_SYSENTER_compat+0x70/0x7f [ 50.998478][ T7872] RIP: 0023:0xf7f29869 [ 51.002997][ T7872] Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 [ 51.022594][ T7872] RSP: 002b:00000000ffa9ccdc EFLAGS: 00000286 ORIG_RAX: 00000000000001a9 [ 51.031020][ T7872] RAX: ffffffffffffffda RBX: 000000000000014a RCX: 0000000020000040 [ 51.038983][ T7872] RDX: 0000000000000002 RSI: 00000000080ea070 RDI: 00000000ffa9cd30 [ 51.046963][ T7872] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 51.054946][ T7872] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 51.062908][ T7872] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 51.071798][ T7872] Kernel Offset: disabled [ 51.076203][ T7872] Rebooting in 86400 seconds..