[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 39.265377][ T26] audit: type=1800 audit(1555110119.972:25): pid=7767 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 39.293643][ T26] audit: type=1800 audit(1555110119.982:26): pid=7767 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 39.315359][ T26] audit: type=1800 audit(1555110119.982:27): pid=7767 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 '10.128.0.220' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 54.077856][ T7919] WARNING: CPU: 1 PID: 7919 at include/linux/cpumask.h:121 io_uring_setup+0x13b2/0x1990 [ 54.087844][ T7919] Kernel panic - not syncing: panic_on_warn set ... [ 54.094495][ T7919] CPU: 1 PID: 7919 Comm: syz-executor076 Not tainted 5.1.0-rc4+ #64 [ 54.102455][ T7919] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 54.112498][ T7919] Call Trace: [ 54.115774][ T7919] dump_stack+0x172/0x1f0 [ 54.120168][ T7919] ? io_uring_setup+0x12e0/0x1990 [ 54.125180][ T7919] panic+0x2cb/0x65c [ 54.129061][ T7919] ? __warn_printk+0xf3/0xf3 [ 54.133754][ T7919] ? io_uring_setup+0x13b2/0x1990 [ 54.138765][ T7919] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 54.144997][ T7919] ? __warn.cold+0x5/0x45 [ 54.149311][ T7919] ? __warn+0xe8/0x1d0 [ 54.153475][ T7919] ? io_uring_setup+0x13b2/0x1990 [ 54.158493][ T7919] __warn.cold+0x20/0x45 [ 54.162769][ T7919] ? io_uring_setup+0x13b2/0x1990 [ 54.167790][ T7919] report_bug+0x263/0x2b0 [ 54.172110][ T7919] do_error_trap+0x11b/0x200 [ 54.176700][ T7919] do_invalid_op+0x37/0x50 [ 54.181097][ T7919] ? io_uring_setup+0x13b2/0x1990 [ 54.186104][ T7919] invalid_op+0x14/0x20 [ 54.190354][ T7919] RIP: 0010:io_uring_setup+0x13b2/0x1990 [ 54.195991][ T7919] Code: 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 80 3c 02 00 0f 84 18 fe ff ff 48 89 df e8 e8 80 e0 ff e9 0b fe ff ff e8 2e 79 a8 ff <0f> 0b e9 db f8 ff ff e8 22 79 a8 ff 49 8d 9c 24 88 00 00 00 48 b8 [ 54.227126][ T7919] RSP: 0018:ffff88809607fdc0 EFLAGS: 00010293 [ 54.233185][ T7919] RAX: ffff8880a1634540 RBX: 0000000000000400 RCX: ffffffff81c80eab [ 54.241147][ T7919] RDX: 0000000000000000 RSI: ffffffff81c815d2 RDI: 0000000000000005 [ 54.249105][ T7919] RBP: ffff88809607fef0 R08: ffff8880a1634540 R09: ffffed1014f5bdc4 [ 54.257164][ T7919] R10: ffffed1014f5bdc3 R11: ffff8880a7adee1f R12: ffff88808a641480 [ 54.265169][ T7919] R13: ffff88809607fec8 R14: ffff88808a6414c0 R15: ffff88808a6414d4 [ 54.273146][ T7919] ? io_uring_setup+0xc8b/0x1990 [ 54.278077][ T7919] ? io_uring_setup+0x13b2/0x1990 [ 54.283248][ T7919] ? io_uring_release+0x50/0x50 [ 54.288093][ T7919] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 54.293536][ T7919] ? do_syscall_64+0x26/0x610 [ 54.298193][ T7919] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 54.304244][ T7919] ? do_syscall_64+0x26/0x610 [ 54.308916][ T7919] ? lockdep_hardirqs_on+0x418/0x5d0 [ 54.314197][ T7919] __x64_sys_io_uring_setup+0x54/0x80 [ 54.319557][ T7919] do_syscall_64+0x103/0x610 [ 54.324149][ T7919] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 54.330078][ T7919] RIP: 0033:0x440239 [ 54.333958][ T7919] 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 54.353552][ T7919] RSP: 002b:00007ffdad1455e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9 [ 54.361956][ T7919] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440239 [ 54.370160][ T7919] RDX: 0000000000400b60 RSI: 0000000020000200 RDI: 0000000000000c9f [ 54.378123][ T7919] RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000 [ 54.386101][ T7919] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000401ac0 [ 54.394083][ T7919] R13: 0000000000401b50 R14: 0000000000000000 R15: 0000000000000000 [ 54.402907][ T7919] Kernel Offset: disabled [ 54.407305][ T7919] Rebooting in 86400 seconds..