[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.802410][ T26] audit: type=1800 audit(1555111145.987:25): pid=7663 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 37.843400][ T26] audit: type=1800 audit(1555111145.987:26): pid=7663 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 37.877948][ T26] audit: type=1800 audit(1555111145.987:27): pid=7663 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 '10.128.0.235' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 47.643621][ T7816] WARNING: CPU: 0 PID: 7816 at include/linux/cpumask.h:121 io_uring_setup+0x13b2/0x1990 [ 47.653364][ T7816] Kernel panic - not syncing: panic_on_warn set ... [ 47.659942][ T7816] CPU: 0 PID: 7816 Comm: syz-executor834 Not tainted 5.1.0-rc4+ #64 [ 47.667896][ T7816] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.678036][ T7816] Call Trace: [ 47.681320][ T7816] dump_stack+0x172/0x1f0 [ 47.685637][ T7816] ? io_uring_setup+0x12e0/0x1990 [ 47.690750][ T7816] panic+0x2cb/0x65c [ 47.694628][ T7816] ? __warn_printk+0xf3/0xf3 [ 47.699225][ T7816] ? io_uring_setup+0x13b2/0x1990 [ 47.704248][ T7816] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 47.710471][ T7816] ? __warn.cold+0x5/0x45 [ 47.714782][ T7816] ? __warn+0xe8/0x1d0 [ 47.718849][ T7816] ? io_uring_setup+0x13b2/0x1990 [ 47.723854][ T7816] __warn.cold+0x20/0x45 [ 47.728078][ T7816] ? io_uring_setup+0x13b2/0x1990 [ 47.733191][ T7816] report_bug+0x263/0x2b0 [ 47.737521][ T7816] do_error_trap+0x11b/0x200 [ 47.742109][ T7816] do_invalid_op+0x37/0x50 [ 47.746519][ T7816] ? io_uring_setup+0x13b2/0x1990 [ 47.751533][ T7816] invalid_op+0x14/0x20 [ 47.755671][ T7816] RIP: 0010:io_uring_setup+0x13b2/0x1990 [ 47.761302][ T7816] 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 [ 47.781175][ T7816] RSP: 0018:ffff888086de7dc0 EFLAGS: 00010293 [ 47.787228][ T7816] RAX: ffff888092bf2440 RBX: 0000000000000406 RCX: ffffffff81c80eab [ 47.795187][ T7816] RDX: 0000000000000000 RSI: ffffffff81c815d2 RDI: 0000000000000005 [ 47.803229][ T7816] RBP: ffff888086de7ef0 R08: ffff888092bf2440 R09: ffffed1013347db4 [ 47.811181][ T7816] R10: ffffed1013347db3 R11: ffff888099a3ed9f R12: ffff88809829ac00 [ 47.819225][ T7816] R13: ffff888086de7ec8 R14: ffff88809829ac40 R15: ffff88809829ac54 [ 47.827192][ T7816] ? io_uring_setup+0xc8b/0x1990 [ 47.832131][ T7816] ? io_uring_setup+0x13b2/0x1990 [ 47.837157][ T7816] ? io_uring_release+0x50/0x50 [ 47.842000][ T7816] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 47.847662][ T7816] ? do_syscall_64+0x26/0x610 [ 47.852323][ T7816] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 47.858447][ T7816] ? do_syscall_64+0x26/0x610 [ 47.863210][ T7816] ? lockdep_hardirqs_on+0x418/0x5d0 [ 47.868498][ T7816] __x64_sys_io_uring_setup+0x54/0x80 [ 47.873865][ T7816] do_syscall_64+0x103/0x610 [ 47.878447][ T7816] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 47.884323][ T7816] RIP: 0033:0x440239 [ 47.888201][ T7816] 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 [ 47.907822][ T7816] RSP: 002b:00007ffcf1743a88 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9 [ 47.916218][ T7816] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440239 [ 47.924171][ T7816] RDX: 0000000000400b60 RSI: 0000000020000140 RDI: 000000000000089e [ 47.932124][ T7816] RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000 [ 47.940097][ T7816] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000401ac0 [ 47.948062][ T7816] R13: 0000000000401b50 R14: 0000000000000000 R15: 0000000000000000 [ 47.956925][ T7816] Kernel Offset: disabled [ 47.961338][ T7816] Rebooting in 86400 seconds..