[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 70.950447][ T26] audit: type=1800 audit(1585463194.665:25): pid=9236 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 70.978670][ T26] audit: type=1800 audit(1585463194.665:26): pid=9236 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 71.021230][ T26] audit: type=1800 audit(1585463194.665:27): pid=9236 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 '10.128.0.7' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 563.639255][T12752] ------------[ cut here ]------------ [ 563.644846][T12752] WARNING: CPU: 0 PID: 12752 at lib/percpu-refcount.c:111 percpu_ref_exit+0xa3/0xd0 [ 563.654217][T12752] Kernel panic - not syncing: panic_on_warn set ... [ 563.660786][T12752] CPU: 0 PID: 12752 Comm: syz-executor526 Not tainted 5.6.0-rc3-next-20200228-syzkaller #0 [ 563.670733][T12752] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 563.680763][T12752] Call Trace: [ 563.684105][T12752] dump_stack+0x188/0x20d [ 563.688426][T12752] ? percpu_ref_exit+0x10/0xd0 [ 563.693208][T12752] panic+0x2e3/0x75c [ 563.697092][T12752] ? add_taint.cold+0x16/0x16 [ 563.701810][T12752] ? printk+0xba/0xed [ 563.705773][T12752] ? kmsg_dump_rewind_nolock+0xd9/0xd9 [ 563.711212][T12752] ? __warn.cold+0x14/0x35 [ 563.715604][T12752] ? __warn+0xd5/0x1c8 [ 563.719654][T12752] ? percpu_ref_exit+0xa3/0xd0 [ 563.724397][T12752] __warn.cold+0x2f/0x35 [ 563.728620][T12752] ? percpu_ref_exit+0xa3/0xd0 [ 563.733365][T12752] report_bug+0x27b/0x2f0 [ 563.737714][T12752] do_error_trap+0x12b/0x220 [ 563.742286][T12752] ? percpu_ref_exit+0xa3/0xd0 [ 563.747044][T12752] do_invalid_op+0x32/0x40 [ 563.751479][T12752] ? percpu_ref_exit+0xa3/0xd0 [ 563.756292][T12752] invalid_op+0x23/0x30 [ 563.760432][T12752] RIP: 0010:percpu_ref_exit+0xa3/0xd0 [ 563.765779][T12752] Code: 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 1a 48 c7 43 08 03 00 00 00 5b 5d 41 5c e9 f2 6e e3 fd e8 ed 6e e3 fd <0f> 0b eb c2 4c 89 e7 e8 01 90 20 fe eb dc e8 7a 8f 20 fe eb aa 4c [ 563.785376][T12752] RSP: 0018:ffffc90002f07c18 EFLAGS: 00010293 [ 563.791431][T12752] RAX: ffff8880966e85c0 RBX: ffff8880a73f0a10 RCX: ffffffff838f262d [ 563.799398][T12752] RDX: 0000000000000000 RSI: ffffffff838f2693 RDI: ffff8880a73f0a28 [ 563.807348][T12752] RBP: 0000607f51637238 R08: ffff8880966e85c0 R09: ffffed1014e7e14a [ 563.815398][T12752] R10: ffffed1014e7e149 R11: ffff8880a73f0a4f R12: ffff8880a73f0a18 [ 563.823352][T12752] R13: ffff8880a2daa1a0 R14: ffff8880a2daa000 R15: ffff88809607ee40 [ 563.831325][T12752] ? percpu_ref_exit+0x3d/0xd0 [ 563.836079][T12752] ? percpu_ref_exit+0xa3/0xd0 [ 563.840831][T12752] ? percpu_ref_exit+0xa3/0xd0 [ 563.845616][T12752] io_sqe_files_unregister+0x8a/0x2f0 [ 563.851056][T12752] ? io_ring_ctx_wait_and_kill+0x864/0xa10 [ 563.856963][T12752] ? lockdep_hardirqs_on+0x417/0x5d0 [ 563.862234][T12752] io_ring_ctx_wait_and_kill+0x4b5/0xa10 [ 563.867934][T12752] ? io_ring_ctx_wait_and_kill+0xa10/0xa10 [ 563.873716][T12752] io_uring_release+0x3e/0x50 [ 563.878526][T12752] __fput+0x2da/0x850 [ 563.882542][T12752] task_work_run+0x13f/0x1b0 [ 563.887178][T12752] do_exit+0xb53/0x2e10 [ 563.891432][T12752] ? mm_update_next_owner+0x7a0/0x7a0 [ 563.896872][T12752] ? up_read+0x1a8/0x750 [ 563.901106][T12752] ? down_read_nested+0x430/0x430 [ 563.906139][T12752] ? handle_mm_fault+0x29e/0x660 [ 563.911074][T12752] do_group_exit+0x125/0x340 [ 563.915662][T12752] __x64_sys_exit_group+0x3a/0x50 [ 563.920682][T12752] do_syscall_64+0xf6/0x790 [ 563.925172][T12752] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 563.931050][T12752] RIP: 0033:0x43fff8 [ 563.934932][T12752] Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0 0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00 [ 563.954647][T12752] RSP: 002b:00007fff68b80a98 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 563.963085][T12752] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043fff8 [ 563.971038][T12752] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 563.978991][T12752] RBP: 00000000004bf830 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 563.987092][T12752] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000001 [ 563.995046][T12752] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 564.004431][T12752] Kernel Offset: disabled [ 564.008799][T12752] Rebooting in 86400 seconds..