[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.640116] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 24.050603] random: sshd: uninitialized urandom read (32 bytes read) [ 24.350706] random: sshd: uninitialized urandom read (32 bytes read) [ 25.244284] random: sshd: uninitialized urandom read (32 bytes read) [ 25.403111] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.15.204' (ECDSA) to the list of known hosts. [ 31.060198] 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 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.155537] ================================================================== [ 31.163033] BUG: KASAN: use-after-free in kernel_accept+0x2a4/0x310 [ 31.169444] Read of size 8 at addr ffff8801a772c5e8 by task kworker/1:3/4569 [ 31.176622] [ 31.178261] CPU: 1 PID: 4569 Comm: kworker/1:3 Not tainted 4.18.0-rc3+ #10 [ 31.185281] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.194649] Workqueue: events smc_tcp_listen_work [ 31.199528] Call Trace: [ 31.202131] dump_stack+0x1c9/0x2b4 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.205770] ? dump_stack_print_info.cold.2+0x52/0x52 [ 31.210965] ? printk+0xa7/0xcf [ 31.214252] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 31.219019] ? kernel_accept+0x2a4/0x310 [ 31.223086] print_address_description+0x6c/0x20b [ 31.227941] ? kernel_accept+0x2a4/0x310 [ 31.232006] kasan_report.cold.7+0x242/0x2fe [ 31.237469] __asan_report_load8_noabort+0x14/0x20 [ 31.242408] kernel_accept+0x2a4/0x310 [ 31.246318] smc_tcp_listen_work+0x222/0xef0 [ 31.250741] ? smc_link_save_peer_info+0x320/0x320 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.255685] ? __lock_is_held+0xb5/0x140 [ 31.259767] process_one_work+0xc73/0x1ba0 [ 31.264009] ? trace_hardirqs_on+0x10/0x10 [ 31.268259] ? pwq_dec_nr_in_flight+0x4a0/0x4a0 [ 31.272945] ? lock_repin_lock+0x430/0x430 [ 31.277210] ? __sched_text_start+0x8/0x8 [ 31.281364] ? lock_downgrade+0x8f0/0x8f0 [ 31.285520] ? graph_lock+0x170/0x170 [ 31.289327] ? graph_lock+0x170/0x170 [ 31.293164] ? lock_acquire+0x1e4/0x540 [ 31.297150] ? worker_thread+0x3dc/0x13c0 [ 31.301304] ? lock_downgrade+0x8f0/0x8f0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.305459] ? lock_release+0xa30/0xa30 [ 31.309445] ? kasan_check_read+0x11/0x20 [ 31.313606] ? do_raw_spin_unlock+0xa7/0x2f0 [ 31.318021] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 31.322617] ? kasan_check_write+0x14/0x20 [ 31.326875] ? do_raw_spin_lock+0xc1/0x200 [ 31.331128] worker_thread+0x189/0x13c0 [ 31.335214] ? process_one_work+0x1ba0/0x1ba0 [ 31.339733] ? __sched_text_start+0x8/0x8 [ 31.343894] ? graph_lock+0x170/0x170 [ 31.347702] ? find_held_lock+0x36/0x1c0 [ 31.351774] ? find_held_lock+0x36/0x1c0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.355846] ? find_held_lock+0x36/0x1c0 [ 31.359921] ? retint_kernel+0x10/0x10 [ 31.363822] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.368849] ? schedule+0xfb/0x450 [ 31.372425] ? __schedule+0x1ed0/0x1ed0 [ 31.376406] ? retint_kernel+0x10/0x10 [ 31.380393] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.385940] ? __kthread_parkme+0x111/0x1d0 [ 31.390270] ? parse_args.cold.15+0x1b3/0x1b3 [ 31.394778] kthread+0x345/0x410 [ 31.398164] ? process_one_work+0x1ba0/0x1ba0 [ 31.402667] ? kthread_bind+0x40/0x40 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.406512] ret_from_fork+0x3a/0x50 [ 31.410235] [ 31.411863] Allocated by task 4568: [ 31.415502] save_stack+0x43/0xd0 [ 31.418962] kasan_kmalloc+0xc4/0xe0 [ 31.422679] kasan_slab_alloc+0x12/0x20 [ 31.426660] kmem_cache_alloc+0x12e/0x760 [ 31.430816] sock_alloc_inode+0x78/0x320 [ 31.434884] alloc_inode+0x63/0x190 [ 31.438521] new_inode_pseudo+0x71/0x1a0 [ 31.442590] sock_alloc+0x41/0x270 [ 31.446136] __sock_create+0x175/0x940 [ 31.450027] sock_create_kern+0x3b/0x50 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.454006] smc_create+0x141/0x360 [ 31.457643] __sock_create+0x53c/0x940 [ 31.461543] __sys_socket+0x106/0x260 [ 31.465351] __x64_sys_socket+0x73/0xb0 [ 31.469330] do_syscall_64+0x1b9/0x820 [ 31.473228] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 31.478411] [ 31.480038] Freed by task 4568: [ 31.483329] save_stack+0x43/0xd0 [ 31.486792] __kasan_slab_free+0x11a/0x170 [ 31.491031] kasan_slab_free+0xe/0x10 [ 31.494878] kmem_cache_free+0x86/0x2d0 [ 31.498896] sock_destroy_inode+0x56/0x70 [ 31.503057] destroy_inode+0x159/0x200 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.506954] evict+0x5d5/0x990 [ 31.510154] iput+0x635/0xaa0 [ 31.513270] __sock_release+0x1f1/0x260 [ 31.517257] sock_release+0x17/0x20 [ 31.520893] smc_release+0x1a8/0x720 [ 31.524615] __sock_release+0xd7/0x260 [ 31.528508] sock_close+0x19/0x20 [ 31.531969] __fput+0x355/0x8b0 [ 31.535257] ____fput+0x15/0x20 [ 31.538546] task_work_run+0x1ec/0x2a0 [ 31.542443] exit_to_usermode_loop+0x313/0x370 [ 31.547031] do_syscall_64+0x6be/0x820 [ 31.550926] entry_SYSCALL_64_after_hwframe+0x49/0xbe executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.556142] [ 31.557775] The buggy address belongs to the object at ffff8801a772c5c0 [ 31.557775] which belongs to the cache sock_inode_cache of size 992 [ 31.572103] The buggy address is located 40 bytes inside of [ 31.572103] 992-byte region [ffff8801a772c5c0, ffff8801a772c9a0) [ 31.585896] The buggy address belongs to the page: [ 31.590843] page:ffffea00069dcb00 count:1 mapcount:0 mapping:ffff8801d9be93c0 index:0xffff8801a772cffd [ 31.600304] flags: 0x2fffc0000000100(slab) executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.604571] raw: 02fffc0000000100 ffffea00069dcac8 ffffea00069dd408 ffff8801d9be93c0 [ 31.612471] raw: ffff8801a772cffd ffff8801a772c140 0000000100000003 0000000000000000 [ 31.620359] page dumped because: kasan: bad access detected [ 31.626077] [ 31.627711] Memory state around the buggy address: [ 31.632647] ffff8801a772c480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 31.640019] ffff8801a772c500: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 31.647480] >ffff8801a772c580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.654841] ^ [ 31.661602] ffff8801a772c600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.668976] ffff8801a772c680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.676335] ================================================================== [ 31.684049] Disabling lock debugging due to kernel taint [ 31.689864] Kernel panic - not syncing: panic_on_warn set ... [ 31.689864] [ 31.697244] CPU: 1 PID: 4569 Comm: kworker/1:3 Tainted: G B 4.18.0-rc3+ #10 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.705643] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.715013] Workqueue: events smc_tcp_listen_work [ 31.719952] Call Trace: [ 31.722549] dump_stack+0x1c9/0x2b4 [ 31.726186] ? dump_stack_print_info.cold.2+0x52/0x52 [ 31.731410] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.736180] panic+0x238/0x4e7 [ 31.739383] ? add_taint.cold.5+0x16/0x16 [ 31.743542] ? do_raw_spin_unlock+0xa7/0x2f0 [ 31.747969] ? do_raw_spin_unlock+0xa7/0x2f0 [ 31.752388] ? kernel_accept+0x2a4/0x310 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.756458] kasan_end_report+0x47/0x4f [ 31.760793] kasan_report.cold.7+0x76/0x2fe [ 31.765130] __asan_report_load8_noabort+0x14/0x20 [ 31.770164] kernel_accept+0x2a4/0x310 [ 31.774082] smc_tcp_listen_work+0x222/0xef0 [ 31.778504] ? smc_link_save_peer_info+0x320/0x320 [ 31.783475] ? __lock_is_held+0xb5/0x140 [ 31.787551] process_one_work+0xc73/0x1ba0 [ 31.791796] ? trace_hardirqs_on+0x10/0x10 [ 31.796042] ? pwq_dec_nr_in_flight+0x4a0/0x4a0 [ 31.800749] ? lock_repin_lock+0x430/0x430 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.805001] ? __sched_text_start+0x8/0x8 [ 31.809245] ? lock_downgrade+0x8f0/0x8f0 [ 31.813409] ? graph_lock+0x170/0x170 [ 31.817219] ? graph_lock+0x170/0x170 [ 31.821071] ? lock_acquire+0x1e4/0x540 [ 31.825052] ? worker_thread+0x3dc/0x13c0 [ 31.829213] ? lock_downgrade+0x8f0/0x8f0 [ 31.833807] ? lock_release+0xa30/0xa30 [ 31.837790] ? kasan_check_read+0x11/0x20 [ 31.841944] ? do_raw_spin_unlock+0xa7/0x2f0 [ 31.846358] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 31.851127] ? kasan_check_write+0x14/0x20 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.855369] ? do_raw_spin_lock+0xc1/0x200 [ 31.859612] worker_thread+0x189/0x13c0 [ 31.863599] ? process_one_work+0x1ba0/0x1ba0 [ 31.868104] ? __sched_text_start+0x8/0x8 [ 31.872256] ? graph_lock+0x170/0x170 [ 31.876074] ? find_held_lock+0x36/0x1c0 [ 31.880148] ? find_held_lock+0x36/0x1c0 [ 31.884216] ? find_held_lock+0x36/0x1c0 [ 31.888286] ? retint_kernel+0x10/0x10 [ 31.892193] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.897277] ? schedule+0xfb/0x450 [ 31.900911] ? __schedule+0x1ed0/0x1ed0 [ 31.904980] ? retint_kernel+0x10/0x10 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.908881] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.914516] ? __kthread_parkme+0x111/0x1d0 [ 31.918884] ? parse_args.cold.15+0x1b3/0x1b3 [ 31.923399] kthread+0x345/0x410 [ 31.926785] ? process_one_work+0x1ba0/0x1ba0 [ 31.931296] ? kthread_bind+0x40/0x40 [ 31.935115] ret_from_fork+0x3a/0x50 [ 31.939425] Dumping ftrace buffer: [ 31.942968] (ftrace buffer empty) [ 31.946699] Kernel Offset: disabled [ 31.950407] Rebooting in 86400 seconds..