[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.876983] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.299072] random: sshd: uninitialized urandom read (32 bytes read) [ 21.548331] random: sshd: uninitialized urandom read (32 bytes read) [ 22.360357] random: sshd: uninitialized urandom read (32 bytes read) [ 115.993045] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.11' (ECDSA) to the list of known hosts. [ 121.575805] random: sshd: uninitialized urandom read (32 bytes read) net.ipv6.conf.syz_tun.accept_dad = 0 [ 121.683188] IPVS: ftp: loaded support on port[0] = 21 net.ipv6.conf.syz_tun.router_solicitations = 0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 133.852029] ================================================================== [ 133.859791] BUG: KASAN: use-after-free in __dev_map_entry_free+0x2a8/0x300 [ 133.866819] Read of size 8 at addr ffff8801d8cfa1c8 by task ksoftirqd/1/18 [ 133.873836] [ 133.875479] CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.18.0-rc1+ #110 [ 133.882411] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 133.892137] Call Trace: [ 133.894754] dump_stack+0x1c9/0x2b4 executing program executing program executing program executing program executing program [ 133.898423] ? dump_stack_print_info.cold.2+0x52/0x52 [ 133.903627] ? printk+0xa7/0xcf [ 133.906921] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 133.911693] ? __dev_map_entry_free+0x2a8/0x300 [ 133.916382] print_address_description+0x6c/0x20b [ 133.921238] ? __dev_map_entry_free+0x2a8/0x300 [ 133.925924] kasan_report.cold.7+0x242/0x2fe [ 133.930357] __asan_report_load8_noabort+0x14/0x20 [ 133.935396] __dev_map_entry_free+0x2a8/0x300 [ 133.939921] ? dev_map_delete_elem+0x100/0x100 [ 133.944532] rcu_process_callbacks+0xed5/0x1850 executing program executing program executing program executing program executing program [ 133.949232] ? call_rcu_sched+0x20/0x20 [ 133.953253] ? lock_downgrade+0x8f0/0x8f0 [ 133.957424] ? finish_task_switch+0x18a/0x890 [ 133.961940] ? kasan_check_read+0x11/0x20 [ 133.966111] ? do_raw_spin_unlock+0xa7/0x2f0 [ 133.970527] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 133.975129] ? compat_start_thread+0x80/0x80 [ 133.979645] ? _raw_spin_unlock_irq+0x27/0x70 [ 133.984172] ? finish_task_switch+0x2ca/0x890 [ 133.988692] ? kasan_check_read+0x11/0x20 [ 133.993038] ? rcu_is_watching+0x8c/0x150 [ 133.997231] ? rcu_pm_notify+0xc0/0xc0 executing program executing program executing program executing program executing program [ 134.001144] __do_softirq+0x2e8/0xb17 [ 134.004974] ? __irqentry_text_end+0x1f97a8/0x1f97a8 [ 134.010096] ? find_held_lock+0x36/0x1c0 [ 134.014180] ? schedule+0xfb/0x450 [ 134.017734] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 134.022778] ? rcu_note_context_switch+0x730/0x730 [ 134.027733] ? check_same_owner+0x340/0x340 [ 134.032067] ? run_ksoftirqd+0x8b/0x100 [ 134.036064] ? takeover_tasklets+0xa60/0xa60 [ 134.040487] run_ksoftirqd+0x86/0x100 [ 134.044305] smpboot_thread_fn+0x417/0x870 [ 134.048657] ? sort_range+0x30/0x30 executing program executing program executing program executing program [ 134.052297] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 134.057327] ? trace_hardirqs_on+0xd/0x10 [ 134.061492] kthread+0x345/0x410 [ 134.064891] ? sort_range+0x30/0x30 [ 134.068550] ? kthread_bind+0x40/0x40 [ 134.072359] ret_from_fork+0x3a/0x50 [ 134.076090] [ 134.077733] Allocated by task 8934: [ 134.081371] save_stack+0x43/0xd0 [ 134.084838] kasan_kmalloc+0xc4/0xe0 [ 134.088738] kmem_cache_alloc_trace+0x152/0x780 [ 134.093416] dev_map_alloc+0x210/0x810 [ 134.097316] map_create+0x39b/0x1020 executing program executing program executing program executing program executing program [ 134.101038] __x64_sys_bpf+0x303/0x510 [ 134.104941] do_syscall_64+0x1b9/0x820 [ 134.108834] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 134.114021] [ 134.115758] Freed by task 26: [ 134.118882] save_stack+0x43/0xd0 [ 134.122348] __kasan_slab_free+0x11a/0x170 [ 134.126601] kasan_slab_free+0xe/0x10 [ 134.130428] kfree+0xd9/0x260 [ 134.133559] dev_map_free+0x502/0x680 [ 134.137383] bpf_map_free_deferred+0xba/0xf0 [ 134.141815] process_one_work+0xc73/0x1ba0 [ 134.146058] worker_thread+0x189/0x13c0 [ 134.150043] kthread+0x345/0x410 executing program executing program executing program executing program executing program [ 134.153428] ret_from_fork+0x3a/0x50 [ 134.157149] [ 134.158794] The buggy address belongs to the object at ffff8801d8cfa0c0 [ 134.158794] which belongs to the cache kmalloc-512 of size 512 [ 134.171458] The buggy address is located 264 bytes inside of [ 134.171458] 512-byte region [ffff8801d8cfa0c0, ffff8801d8cfa2c0) [ 134.183346] The buggy address belongs to the page: [ 134.188301] page:ffffea0007633e80 count:1 mapcount:0 mapping:ffff8801da800940 index:0x0 [ 134.196468] flags: 0x2fffc0000000100(slab) executing program executing program executing program executing program executing program [ 134.200716] raw: 02fffc0000000100 ffffea0007620148 ffffea000763d6c8 ffff8801da800940 [ 134.208609] raw: 0000000000000000 ffff8801d8cfa0c0 0000000100000006 0000000000000000 [ 134.216513] page dumped because: kasan: bad access detected [ 134.222233] [ 134.223854] Memory state around the buggy address: [ 134.228794] ffff8801d8cfa080: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 134.236161] ffff8801d8cfa100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 134.243527] >ffff8801d8cfa180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb executing program executing program executing program executing program executing program [ 134.250881] ^ [ 134.256604] ffff8801d8cfa200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 134.263976] ffff8801d8cfa280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 134.271340] ================================================================== [ 134.278728] Disabling lock debugging due to kernel taint [ 134.284218] Kernel panic - not syncing: panic_on_warn set ... [ 134.284218] [ 134.291618] CPU: 1 PID: 18 Comm: ksoftirqd/1 Tainted: G B 4.18.0-rc1+ #110 executing program executing program executing program executing program executing program executing program executing program [ 134.299943] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 134.309310] Call Trace: [ 134.311906] dump_stack+0x1c9/0x2b4 [ 134.315551] ? dump_stack_print_info.cold.2+0x52/0x52 [ 134.320777] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 134.325540] panic+0x238/0x4e7 [ 134.328739] ? add_taint.cold.5+0x16/0x16 [ 134.332892] ? do_raw_spin_unlock+0xa7/0x2f0 [ 134.337307] ? do_raw_spin_unlock+0xa7/0x2f0 [ 134.341724] ? __dev_map_entry_free+0x2a8/0x300 [ 134.346402] kasan_end_report+0x47/0x4f executing program executing program executing program executing program executing program executing program executing program [ 134.350385] kasan_report.cold.7+0x76/0x2fe [ 134.354720] __asan_report_load8_noabort+0x14/0x20 [ 134.359666] __dev_map_entry_free+0x2a8/0x300 [ 134.364192] ? dev_map_delete_elem+0x100/0x100 [ 134.368790] rcu_process_callbacks+0xed5/0x1850 [ 134.373475] ? call_rcu_sched+0x20/0x20 [ 134.377463] ? lock_downgrade+0x8f0/0x8f0 [ 134.381644] ? finish_task_switch+0x18a/0x890 [ 134.386151] ? kasan_check_read+0x11/0x20 [ 134.390478] ? do_raw_spin_unlock+0xa7/0x2f0 [ 134.394902] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 134.399638] ? compat_start_thread+0x80/0x80 executing program executing program executing program executing program executing program executing program [ 134.404062] ? _raw_spin_unlock_irq+0x27/0x70 [ 134.408588] ? finish_task_switch+0x2ca/0x890 [ 134.413105] ? kasan_check_read+0x11/0x20 [ 134.417437] ? rcu_is_watching+0x8c/0x150 [ 134.421592] ? rcu_pm_notify+0xc0/0xc0 [ 134.425497] __do_softirq+0x2e8/0xb17 [ 134.429399] ? __irqentry_text_end+0x1f97a8/0x1f97a8 [ 134.434512] ? find_held_lock+0x36/0x1c0 [ 134.438580] ? schedule+0xfb/0x450 [ 134.442128] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 134.447157] ? rcu_note_context_switch+0x730/0x730 executing program executing program executing program executing program executing program executing program [ 134.452100] ? check_same_owner+0x340/0x340 [ 134.456440] ? run_ksoftirqd+0x8b/0x100 [ 134.460450] ? takeover_tasklets+0xa60/0xa60 [ 134.464875] run_ksoftirqd+0x86/0x100 [ 134.468686] smpboot_thread_fn+0x417/0x870 [ 134.472940] ? sort_range+0x30/0x30 [ 134.476584] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 134.481612] ? trace_hardirqs_on+0xd/0x10 [ 134.485791] kthread+0x345/0x410 [ 134.489166] ? sort_range+0x30/0x30 [ 134.492797] ? kthread_bind+0x40/0x40 [ 134.496611] ret_from_fork+0x3a/0x50 [ 134.500763] Dumping ftrace buffer: [ 134.504296] (ftrace buffer empty) [ 134.507983] Kernel Offset: disabled [ 134.511588] Rebooting in 86400 seconds..