[ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.117' (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 syzkaller login: [ 27.906216] ================================================================== [ 27.913615] BUG: KASAN: use-after-free in __lock_acquire+0x2c57/0x3f20 [ 27.920377] Read of size 8 at addr ffff8880abdd46a0 by task kworker/u4:0/5 [ 27.927411] [ 27.929039] CPU: 1 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.292-syzkaller #0 [ 27.936397] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 [ 27.946278] Workqueue: tipc_rcv tipc_recv_work [ 27.950854] Call Trace: executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 27.953445] dump_stack+0x1b2/0x281 [ 27.957075] print_address_description.cold+0x54/0x1d3 [ 27.962353] kasan_report_error.cold+0x8a/0x191 [ 27.967030] ? __lock_acquire+0x2c57/0x3f20 [ 27.971365] __asan_report_load8_noabort+0x68/0x70 [ 27.976294] ? tipc_subscrb_rcv_cb+0x370/0xa40 [ 27.980878] ? __lock_acquire+0x2c57/0x3f20 [ 27.985230] __lock_acquire+0x2c57/0x3f20 [ 27.989385] ? io_schedule_timeout+0x140/0x140 [ 27.993967] ? __wake_up_common_lock+0xcd/0x140 [ 27.998644] ? trace_hardirqs_on+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 [ 28.002879] ? trace_hardirqs_on+0x10/0x10 [ 28.007116] ? preempt_schedule_common+0x45/0xc0 [ 28.011973] ? ___preempt_schedule+0x16/0x18 [ 28.016422] ? tipc_recvmsg+0x43e/0x9e0 [ 28.020405] ? __local_bh_enable_ip+0x132/0x170 [ 28.025076] lock_acquire+0x170/0x3f0 [ 28.028878] ? tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.033461] _raw_spin_lock_bh+0x2f/0x40 [ 28.037532] ? tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.042125] tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.046539] tipc_receive_from_sock+0x25c/0x450 [ 28.051211] ? trace_hardirqs_on+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 [ 28.055455] ? lock_acquire+0x170/0x3f0 [ 28.059434] ? tipc_close_conn+0x200/0x200 [ 28.063674] tipc_recv_work+0x75/0xd0 [ 28.067477] process_one_work+0x793/0x14a0 [ 28.071721] ? work_busy+0x320/0x320 [ 28.075434] ? worker_thread+0x158/0xff0 [ 28.079498] ? _raw_spin_unlock_irq+0x24/0x80 [ 28.084001] worker_thread+0x5cc/0xff0 [ 28.087890] ? rescuer_thread+0xc80/0xc80 [ 28.092037] kthread+0x30d/0x420 [ 28.096103] ? kthread_create_on_node+0xd0/0xd0 [ 28.100780] ret_from_fork+0x24/0x30 [ 28.104489] executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 28.106118] Allocated by task 5: [ 28.109486] kasan_kmalloc+0xeb/0x160 [ 28.113461] kmem_cache_alloc_trace+0x131/0x3d0 [ 28.118127] tipc_subscrb_connect_cb+0x40/0x150 [ 28.122798] tipc_accept_from_sock+0x25b/0x400 [ 28.127390] tipc_recv_work+0x75/0xd0 [ 28.131192] process_one_work+0x793/0x14a0 [ 28.135426] worker_thread+0x5cc/0xff0 [ 28.139312] kthread+0x30d/0x420 [ 28.142683] ret_from_fork+0x24/0x30 [ 28.146391] [ 28.148014] Freed by task 35: [ 28.151115] kasan_slab_free+0xc3/0x1a0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 28.155084] kfree+0xc9/0x250 [ 28.158189] tipc_subscrb_put+0x22/0x30 [ 28.162512] tipc_close_conn+0x16a/0x200 [ 28.166572] tipc_send_work+0x41e/0x520 [ 28.170543] process_one_work+0x793/0x14a0 [ 28.174773] worker_thread+0x5cc/0xff0 [ 28.178661] kthread+0x30d/0x420 [ 28.182036] ret_from_fork+0x24/0x30 [ 28.185736] [ 28.187359] The buggy address belongs to the object at ffff8880abdd4680 [ 28.187359] which belongs to the cache kmalloc-96 of size 96 [ 28.199839] The buggy address is located 32 bytes inside of executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 28.199839] 96-byte region [ffff8880abdd4680, ffff8880abdd46e0) [ 28.211531] The buggy address belongs to the page: [ 28.216454] page:ffffea0002af7500 count:1 mapcount:0 mapping:ffff8880abdd4000 index:0xffff8880abdd4600 [ 28.225902] flags: 0xfff00000000100(slab) [ 28.230053] raw: 00fff00000000100 ffff8880abdd4000 ffff8880abdd4600 0000000100000015 [ 28.237935] raw: ffffea0002b04de0 ffffea0002b0d260 ffff88813fe744c0 0000000000000000 [ 28.245807] page dumped because: kasan: bad access detected [ 28.251505] executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 28.253122] Memory state around the buggy address: [ 28.258042] ffff8880abdd4580: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.265398] ffff8880abdd4600: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.272764] >ffff8880abdd4680: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.280112] ^ [ 28.284520] ffff8880abdd4700: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.291883] ffff8880abdd4780: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.299234] ================================================================== executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 28.306583] Disabling lock debugging due to kernel taint [ 28.312027] Kernel panic - not syncing: panic_on_warn set ... [ 28.312027] [ 28.319389] CPU: 1 PID: 5 Comm: kworker/u4:0 Tainted: G B 4.14.292-syzkaller #0 [ 28.327965] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 [ 28.337359] Workqueue: tipc_rcv tipc_recv_work [ 28.341943] Call Trace: [ 28.344525] dump_stack+0x1b2/0x281 [ 28.348151] panic+0x1f9/0x42d [ 28.351340] ? add_taint.cold+0x16/0x16 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 28.355313] ? lock_downgrade+0x740/0x740 [ 28.359462] kasan_end_report+0x43/0x49 [ 28.363435] kasan_report_error.cold+0xa7/0x191 [ 28.368188] ? __lock_acquire+0x2c57/0x3f20 [ 28.372506] __asan_report_load8_noabort+0x68/0x70 [ 28.377432] ? tipc_subscrb_rcv_cb+0x370/0xa40 [ 28.382010] ? __lock_acquire+0x2c57/0x3f20 [ 28.386328] __lock_acquire+0x2c57/0x3f20 [ 28.390478] ? io_schedule_timeout+0x140/0x140 [ 28.395074] ? __wake_up_common_lock+0xcd/0x140 [ 28.399745] ? trace_hardirqs_on+0x10/0x10 [ 28.403982] ? trace_hardirqs_on+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 [ 28.408219] ? preempt_schedule_common+0x45/0xc0 [ 28.412972] ? ___preempt_schedule+0x16/0x18 [ 28.417384] ? tipc_recvmsg+0x43e/0x9e0 [ 28.421369] ? __local_bh_enable_ip+0x132/0x170 [ 28.426039] lock_acquire+0x170/0x3f0 [ 28.429843] ? tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.434428] _raw_spin_lock_bh+0x2f/0x40 [ 28.438489] ? tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.443075] tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.447492] tipc_receive_from_sock+0x25c/0x450 [ 28.452163] ? trace_hardirqs_on+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 [ 28.456486] ? lock_acquire+0x170/0x3f0 [ 28.460458] ? tipc_close_conn+0x200/0x200 [ 28.464696] tipc_recv_work+0x75/0xd0 [ 28.468494] process_one_work+0x793/0x14a0 [ 28.472726] ? work_busy+0x320/0x320 [ 28.476441] ? worker_thread+0x158/0xff0 [ 28.482502] ? _raw_spin_unlock_irq+0x24/0x80 [ 28.486993] worker_thread+0x5cc/0xff0 [ 28.490880] ? rescuer_thread+0xc80/0xc80 [ 28.495025] kthread+0x30d/0x420 [ 28.498400] ? kthread_create_on_node+0xd0/0xd0 [ 28.503072] ret_from_fork+0x24/0x30 [ 28.506946] Kernel Offset: disabled [ 28.510554] Rebooting in 86400 seconds..