Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.33' (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 syzkaller login: [ 27.831450] ================================================================== [ 27.838820] BUG: KASAN: use-after-free in __lock_acquire+0x2c57/0x3f20 [ 27.845465] Read of size 8 at addr ffff8880ac397120 by task kworker/u4:3/1341 [ 27.852711] [ 27.854318] CPU: 0 PID: 1341 Comm: kworker/u4:3 Not tainted 4.14.280-syzkaller #0 [ 27.861907] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.871253] Workqueue: tipc_rcv tipc_recv_work [ 27.875809] Call Trace: [ 27.878373] dump_stack+0x1b2/0x281 [ 27.881974] print_address_description.cold+0x54/0x1d3 [ 27.887223] kasan_report_error.cold+0x8a/0x191 [ 27.891874] ? __lock_acquire+0x2c57/0x3f20 [ 27.896172] __asan_report_load8_noabort+0x68/0x70 [ 27.901077] ? tipc_subscrb_rcv_cb+0x2c0/0xa40 [ 27.905630] ? __lock_acquire+0x2c57/0x3f20 [ 27.909935] __lock_acquire+0x2c57/0x3f20 [ 27.914059] ? io_schedule_timeout+0x140/0x140 [ 27.918623] ? __wake_up_common_lock+0xcd/0x140 [ 27.923267] ? trace_hardirqs_on+0x10/0x10 [ 27.927478] ? trace_hardirqs_on+0x10/0x10 [ 27.931686] ? preempt_schedule_common+0x45/0xc0 [ 27.936765] ? ___preempt_schedule+0x16/0x18 [ 27.941150] ? tipc_recvmsg+0x43e/0x9e0 [ 27.945098] ? __local_bh_enable_ip+0x132/0x170 [ 27.949740] lock_acquire+0x170/0x3f0 [ 27.953516] ? tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 27.958072] _raw_spin_lock_bh+0x2f/0x40 [ 27.962104] ? tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 27.966670] tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 27.971107] tipc_receive_from_sock+0x25c/0x450 [ 27.975754] ? trace_hardirqs_on+0x10/0x10 [ 27.979963] ? lock_acquire+0x170/0x3f0 [ 27.983921] ? tipc_close_conn+0x200/0x200 [ 27.988137] tipc_recv_work+0x75/0xd0 [ 27.991922] process_one_work+0x793/0x14a0 [ 27.996139] ? work_busy+0x320/0x320 [ 27.999830] ? worker_thread+0x158/0xff0 [ 28.003866] ? _raw_spin_unlock_irq+0x24/0x80 [ 28.008337] worker_thread+0x5cc/0xff0 [ 28.012199] ? rescuer_thread+0xc80/0xc80 [ 28.016319] kthread+0x30d/0x420 [ 28.019660] ? kthread_create_on_node+0xd0/0xd0 [ 28.024304] ret_from_fork+0x24/0x30 [ 28.027989] [ 28.029592] Allocated by task 1341: [ 28.033196] kasan_kmalloc+0xeb/0x160 [ 28.036971] kmem_cache_alloc_trace+0x131/0x3d0 [ 28.041622] tipc_subscrb_connect_cb+0x40/0x150 [ 28.046280] tipc_accept_from_sock+0x25b/0x400 [ 28.050847] tipc_recv_work+0x75/0xd0 [ 28.054629] process_one_work+0x793/0x14a0 [ 28.058840] worker_thread+0x5cc/0xff0 [ 28.062713] kthread+0x30d/0x420 [ 28.066058] ret_from_fork+0x24/0x30 [ 28.069740] [ 28.071345] Freed by task 5: [ 28.074340] kasan_slab_free+0xc3/0x1a0 [ 28.078289] kfree+0xc9/0x250 [ 28.081381] tipc_subscrb_put+0x22/0x30 [ 28.085333] tipc_close_conn+0x16a/0x200 [ 28.089370] tipc_send_work+0x41e/0x520 [ 28.093325] process_one_work+0x793/0x14a0 [ 28.097537] worker_thread+0x5cc/0xff0 [ 28.101401] kthread+0x30d/0x420 [ 28.104743] ret_from_fork+0x24/0x30 [ 28.108428] [ 28.110033] The buggy address belongs to the object at ffff8880ac397100 [ 28.110033] which belongs to the cache kmalloc-96 of size 96 [ 28.122485] The buggy address is located 32 bytes inside of [ 28.122485] 96-byte region [ffff8880ac397100, ffff8880ac397160) [ 28.134159] The buggy address belongs to the page: [ 28.139061] page:ffffea0002b0e5c0 count:1 mapcount:0 mapping:ffff8880ac397000 index:0xffff8880ac397b00 [ 28.148479] flags: 0xfff00000000100(slab) [ 28.152599] raw: 00fff00000000100 ffff8880ac397000 ffff8880ac397b00 0000000100000014 [ 28.160450] raw: ffffea0002d1d820 ffffea000286f3a0 ffff88813fe744c0 0000000000000000 [ 28.168300] page dumped because: kasan: bad access detected [ 28.173977] [ 28.175576] Memory state around the buggy address: [ 28.180481] ffff8880ac397000: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.187813] ffff8880ac397080: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.195152] >ffff8880ac397100: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.202486] ^ [ 28.206866] ffff8880ac397180: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.214197] ffff8880ac397200: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 28.221526] ================================================================== [ 28.228863] Disabling lock debugging due to kernel taint [ 28.234285] Kernel panic - not syncing: panic_on_warn set ... [ 28.234285] [ 28.241619] CPU: 0 PID: 1341 Comm: kworker/u4:3 Tainted: G B 4.14.280-syzkaller #0 [ 28.250426] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.259762] Workqueue: tipc_rcv tipc_recv_work [ 28.264406] Call Trace: [ 28.266971] dump_stack+0x1b2/0x281 [ 28.270573] panic+0x1f9/0x42d [ 28.273754] ? add_taint.cold+0x16/0x16 [ 28.277732] ? lock_downgrade+0x740/0x740 [ 28.281864] kasan_end_report+0x43/0x49 [ 28.285825] kasan_report_error.cold+0xa7/0x191 [ 28.290479] ? __lock_acquire+0x2c57/0x3f20 [ 28.294781] __asan_report_load8_noabort+0x68/0x70 [ 28.299685] ? tipc_subscrb_rcv_cb+0x2c0/0xa40 [ 28.304240] ? __lock_acquire+0x2c57/0x3f20 [ 28.308535] __lock_acquire+0x2c57/0x3f20 [ 28.312660] ? io_schedule_timeout+0x140/0x140 [ 28.317218] ? __wake_up_common_lock+0xcd/0x140 [ 28.321859] ? trace_hardirqs_on+0x10/0x10 [ 28.326069] ? trace_hardirqs_on+0x10/0x10 [ 28.330276] ? preempt_schedule_common+0x45/0xc0 [ 28.335012] ? ___preempt_schedule+0x16/0x18 [ 28.339397] ? tipc_recvmsg+0x43e/0x9e0 [ 28.343371] ? __local_bh_enable_ip+0x132/0x170 [ 28.348033] lock_acquire+0x170/0x3f0 [ 28.351810] ? tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.356365] _raw_spin_lock_bh+0x2f/0x40 [ 28.360402] ? tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.364955] tipc_subscrb_rcv_cb+0x4d4/0xa40 [ 28.369337] tipc_receive_from_sock+0x25c/0x450 [ 28.373980] ? trace_hardirqs_on+0x10/0x10 [ 28.378190] ? lock_acquire+0x170/0x3f0 [ 28.382139] ? tipc_close_conn+0x200/0x200 [ 28.386348] tipc_recv_work+0x75/0xd0 [ 28.390210] process_one_work+0x793/0x14a0 [ 28.394416] ? work_busy+0x320/0x320 [ 28.398102] ? worker_thread+0x158/0xff0 [ 28.402137] ? _raw_spin_unlock_irq+0x24/0x80 [ 28.406604] worker_thread+0x5cc/0xff0 [ 28.410475] ? rescuer_thread+0xc80/0xc80 [ 28.414599] kthread+0x30d/0x420 [ 28.417946] ? kthread_create_on_node+0xd0/0xd0 [ 28.422589] ret_from_fork+0x24/0x30 [ 28.426447] Kernel Offset: disabled [ 28.430055] Rebooting in 86400 seconds..