[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 15.796724] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.751732] random: sshd: uninitialized urandom read (32 bytes read) [ 20.076367] random: sshd: uninitialized urandom read (32 bytes read) [ 20.746575] random: sshd: uninitialized urandom read (32 bytes read) [ 69.576588] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.51' (ECDSA) to the list of known hosts. [ 75.455468] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 76.704071] ================================================================== [ 76.711519] BUG: KASAN: use-after-free in work_is_static_object+0x39/0x40 [ 76.711538] Read of size 8 at addr ffff8801b9985620 by task kworker/1:1/40 [ 76.726610] [ 76.728241] CPU: 1 PID: 40 Comm: kworker/1:1 Not tainted 4.18.0-rc4-next-20180713+ #7 [ 76.736203] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 76.745568] Workqueue: events p9_poll_workfn [ 76.749995] Call Trace: executing program [ 76.752598] dump_stack+0x1c9/0x2b4 [ 76.752616] ? dump_stack_print_info.cold.2+0x52/0x52 [ 76.761441] ? printk+0xa7/0xcf [ 76.764723] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 76.769482] ? work_is_static_object+0x39/0x40 [ 76.774084] print_address_description+0x6c/0x20b [ 76.778932] ? work_is_static_object+0x39/0x40 [ 76.783603] kasan_report.cold.7+0x242/0x30d [ 76.788019] __asan_report_load8_noabort+0x14/0x20 [ 76.792975] work_is_static_object+0x39/0x40 [ 76.792990] debug_object_activate+0x2fc/0x690 executing program [ 76.793002] ? __wake_up_common+0x740/0x740 [ 76.793020] ? debug_object_assert_init+0x4b0/0x4b0 [ 76.811368] __queue_work+0x1ca/0x1410 [ 76.815261] ? __wake_up+0xe/0x10 [ 76.818711] ? p9_client_cb+0x62/0x80 [ 76.822516] ? flush_rcu_work+0x90/0x90 [ 76.826751] ? p9_fd_cancelled+0x2f0/0x2f0 [ 76.831002] ? lock_acquire+0x1e4/0x540 [ 76.831022] ? p9_poll_workfn+0x3ec/0x6d0 [ 76.839144] ? lock_downgrade+0x8f0/0x8f0 [ 76.843295] ? mounts_poll+0x1f9/0x290 [ 76.847198] queue_work_on+0x19a/0x1e0 executing program executing program [ 76.851112] p9_poll_workfn+0x55e/0x6d0 [ 76.855086] ? p9_read_work+0x1060/0x1060 [ 76.859247] ? lock_acquire+0x1e4/0x540 [ 76.863229] ? process_one_work+0xb9b/0x1ba0 [ 76.867656] ? kasan_check_read+0x11/0x20 [ 76.867679] ? lock_release+0xa30/0xa30 [ 76.876165] ? kasan_check_read+0x11/0x20 [ 76.880333] ? do_raw_spin_unlock+0xa7/0x2f0 [ 76.884740] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 76.889324] ? read_word_at_a_time+0x20/0x20 [ 76.893733] ? compat_start_thread+0x80/0x80 [ 76.898136] ? dequeue_entity+0x15e0/0x15e0 executing program [ 76.902464] process_one_work+0xc73/0x1ba0 [ 76.906712] ? trace_hardirqs_on+0x10/0x10 [ 76.906730] ? pwq_dec_nr_in_flight+0x4a0/0x4a0 [ 76.915608] ? lock_repin_lock+0x430/0x430 [ 76.919827] ? __sched_text_start+0x8/0x8 [ 76.924561] ? lock_downgrade+0x8f0/0x8f0 [ 76.928688] ? graph_lock+0x170/0x170 [ 76.932474] ? graph_lock+0x170/0x170 [ 76.936297] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 76.941051] ? retint_kernel+0x10/0x10 [ 76.944932] ? lock_acquire+0x1e4/0x540 [ 76.944941] ? worker_thread+0x3dc/0x13c0 executing program [ 76.944956] ? lock_downgrade+0x8f0/0x8f0 [ 76.957214] ? lock_release+0xa30/0xa30 [ 76.961182] ? kasan_check_read+0x11/0x20 [ 76.965325] ? do_raw_spin_unlock+0xa7/0x2f0 [ 76.969710] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 76.974284] ? kasan_check_write+0x14/0x20 [ 76.978508] ? do_raw_spin_lock+0xc1/0x200 [ 76.982741] worker_thread+0x189/0x13c0 [ 76.982756] ? process_one_work+0x1ba0/0x1ba0 [ 76.991209] ? graph_lock+0x170/0x170 [ 76.994996] ? graph_lock+0x170/0x170 [ 76.998783] ? find_held_lock+0x36/0x1c0 executing program [ 77.002823] ? find_held_lock+0x36/0x1c0 [ 77.007247] ? kasan_check_read+0x11/0x20 [ 77.011374] ? do_raw_spin_unlock+0xa7/0x2f0 [ 77.015765] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 77.020868] ? __kthread_parkme+0x58/0x1b0 [ 77.020881] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 77.020895] ? trace_hardirqs_on+0xd/0x10 [ 77.034243] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 77.039758] ? __kthread_parkme+0x106/0x1b0 [ 77.044056] kthread+0x345/0x410 [ 77.047412] ? process_one_work+0x1ba0/0x1ba0 executing program executing program [ 77.052233] ? kthread_bind+0x40/0x40 [ 77.056023] ret_from_fork+0x3a/0x50 [ 77.059724] [ 77.059730] Allocated by task 4468: [ 77.059741] save_stack+0x43/0xd0 [ 77.059755] kasan_kmalloc+0xc4/0xe0 [ 77.072120] kmem_cache_alloc_trace+0x152/0x780 [ 77.076779] p9_fd_create+0x1a7/0x3f0 [ 77.080557] p9_client_create+0x8ed/0x1770 [ 77.085300] v9fs_session_init+0x21a/0x1a80 [ 77.089841] v9fs_mount+0x7c/0x900 [ 77.093373] legacy_get_tree+0x118/0x440 [ 77.097440] vfs_get_tree+0x1cb/0x5c0 [ 77.097448] do_mount+0x6c1/0x1fb0 executing program [ 77.097461] ksys_mount+0x12d/0x140 [ 77.108396] __x64_sys_mount+0xbe/0x150 [ 77.112353] do_syscall_64+0x1b9/0x820 [ 77.116221] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 77.121383] [ 77.122989] Freed by task 4468: [ 77.126249] save_stack+0x43/0xd0 [ 77.129680] __kasan_slab_free+0x11a/0x170 [ 77.133902] kasan_slab_free+0xe/0x10 [ 77.133909] kfree+0xd9/0x260 [ 77.133917] p9_fd_close+0x416/0x5b0 [ 77.133923] p9_client_create+0xa9a/0x1770 [ 77.133930] v9fs_session_init+0x21a/0x1a80 executing program [ 77.133945] v9fs_mount+0x7c/0x900 [ 77.156596] legacy_get_tree+0x118/0x440 [ 77.160637] vfs_get_tree+0x1cb/0x5c0 [ 77.164424] do_mount+0x6c1/0x1fb0 [ 77.167951] ksys_mount+0x12d/0x140 [ 77.171590] __x64_sys_mount+0xbe/0x150 [ 77.171605] do_syscall_64+0x1b9/0x820 [ 77.171626] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 77.184670] [ 77.186285] The buggy address belongs to the object at ffff8801b9985500 [ 77.186285] which belongs to the cache kmalloc-512 of size 512 [ 77.198964] The buggy address is located 288 bytes inside of executing program executing program [ 77.198964] 512-byte region [ffff8801b9985500, ffff8801b9985700) [ 77.210886] The buggy address belongs to the page: [ 77.210898] page:ffffea0006e66140 count:1 mapcount:0 mapping:ffff8801da800940 index:0x0 [ 77.224227] flags: 0x2fffc0000000100(slab) [ 77.228444] raw: 02fffc0000000100 ffffea00070a8148 ffffea0006f7d348 ffff8801da800940 [ 77.236320] raw: 0000000000000000 ffff8801b9985000 0000000100000006 0000000000000000 [ 77.244183] page dumped because: kasan: bad access detected [ 77.249885] [ 77.249888] Memory state around the buggy address: executing program [ 77.249896] ffff8801b9985500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 77.249902] ffff8801b9985580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 77.249907] >ffff8801b9985600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 77.249910] ^ [ 77.249915] ffff8801b9985680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 77.249920] ffff8801b9985700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 77.249929] ================================================================== [ 77.305250] Kernel panic - not syncing: panic_on_warn set ... [ 77.305250] [ 77.305262] CPU: 1 PID: 40 Comm: kworker/1:1 Tainted: G B 4.18.0-rc4-next-20180713+ #7 [ 77.305266] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 77.305281] Workqueue: events p9_poll_workfn [ 77.305285] Call Trace: [ 77.305298] dump_stack+0x1c9/0x2b4 [ 77.305307] ? dump_stack_print_info.cold.2+0x52/0x52 [ 77.305318] ? lock_downgrade+0x8f0/0x8f0 [ 77.305326] ? work_is_static_object+0x39/0x40 [ 77.305336] panic+0x238/0x4e7 [ 77.305344] ? add_taint.cold.5+0x16/0x16 [ 77.305354] ? print_shadow_for_address+0xba/0x116 [ 77.305361] ? do_raw_spin_unlock+0xa7/0x2f0 [ 77.305368] ? work_is_static_object+0x39/0x40 [ 77.305374] kasan_end_report+0x47/0x4f [ 77.305381] kasan_report.cold.7+0x76/0x30d [ 77.305389] __asan_report_load8_noabort+0x14/0x20 [ 77.305396] work_is_static_object+0x39/0x40 [ 77.305405] debug_object_activate+0x2fc/0x690 [ 77.305411] ? __wake_up_common+0x740/0x740 [ 77.305419] ? debug_object_assert_init+0x4b0/0x4b0 [ 77.305429] __queue_work+0x1ca/0x1410 [ 77.305436] ? __wake_up+0xe/0x10 [ 77.305442] ? p9_client_cb+0x62/0x80 [ 77.305450] ? flush_rcu_work+0x90/0x90 [ 77.305460] ? p9_fd_cancelled+0x2f0/0x2f0 [ 77.305475] ? lock_acquire+0x1e4/0x540 [ 77.305486] ? p9_poll_workfn+0x3ec/0x6d0 [ 77.305497] ? lock_downgrade+0x8f0/0x8f0 [ 77.305509] ? mounts_poll+0x1f9/0x290 [ 77.305519] queue_work_on+0x19a/0x1e0 [ 77.305527] p9_poll_workfn+0x55e/0x6d0 [ 77.305536] ? p9_read_work+0x1060/0x1060 [ 77.305545] ? lock_acquire+0x1e4/0x540 [ 77.305552] ? process_one_work+0xb9b/0x1ba0 [ 77.305561] ? kasan_check_read+0x11/0x20 [ 77.305569] ? lock_release+0xa30/0xa30 [ 77.305576] ? kasan_check_read+0x11/0x20 [ 77.305583] ? do_raw_spin_unlock+0xa7/0x2f0 [ 77.305590] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 77.305597] ? read_word_at_a_time+0x20/0x20 [ 77.305608] ? compat_start_thread+0x80/0x80 [ 77.305617] ? dequeue_entity+0x15e0/0x15e0 [ 77.305625] process_one_work+0xc73/0x1ba0 [ 77.305633] ? trace_hardirqs_on+0x10/0x10 [ 77.305643] ? pwq_dec_nr_in_flight+0x4a0/0x4a0 [ 77.305651] ? lock_repin_lock+0x430/0x430 [ 77.305663] ? __sched_text_start+0x8/0x8 [ 77.305671] ? lock_downgrade+0x8f0/0x8f0 [ 77.305679] ? graph_lock+0x170/0x170 [ 77.305686] ? graph_lock+0x170/0x170 [ 77.305696] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 77.305705] ? retint_kernel+0x10/0x10 [ 77.305716] ? lock_acquire+0x1e4/0x540 [ 77.305723] ? worker_thread+0x3dc/0x13c0 [ 77.305731] ? lock_downgrade+0x8f0/0x8f0 [ 77.305739] ? lock_release+0xa30/0xa30 [ 77.305747] ? kasan_check_read+0x11/0x20 [ 77.305754] ? do_raw_spin_unlock+0xa7/0x2f0 [ 77.305761] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 77.305769] ? kasan_check_write+0x14/0x20 [ 77.305775] ? do_raw_spin_lock+0xc1/0x200 [ 77.305784] worker_thread+0x189/0x13c0 [ 77.305795] ? process_one_work+0x1ba0/0x1ba0 [ 77.305803] ? graph_lock+0x170/0x170 [ 77.305811] ? graph_lock+0x170/0x170 [ 77.305818] ? find_held_lock+0x36/0x1c0 [ 77.305828] ? find_held_lock+0x36/0x1c0 [ 77.305840] ? kasan_check_read+0x11/0x20 [ 77.305847] ? do_raw_spin_unlock+0xa7/0x2f0 [ 77.305869] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 77.305879] ? __kthread_parkme+0x58/0x1b0 [ 77.305889] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 77.305900] ? trace_hardirqs_on+0xd/0x10 [ 77.305913] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 77.305921] ? __kthread_parkme+0x106/0x1b0 [ 77.305931] kthread+0x345/0x410 [ 77.305941] ? process_one_work+0x1ba0/0x1ba0 [ 77.305948] ? kthread_bind+0x40/0x40 [ 77.305959] ret_from_fork+0x3a/0x50 [ 77.306481] Dumping ftrace buffer: [ 77.306485] (ftrace buffer empty) [ 77.306488] Kernel Offset: disabled [ 77.670001] Rebooting in 86400 seconds..