Warning: Permanently added '10.128.0.229' (ECDSA) to the list of known hosts. syzkaller login: [ 38.283442] audit: type=1400 audit(1596403647.707:8): avc: denied { execmem } for pid=6480 comm="syz-executor311" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 38.295372] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.466934] ================================================================== [ 39.474459] BUG: KASAN: use-after-free in hci_send_acl+0xad6/0xc70 [ 39.480781] Read of size 8 at addr ffff88809f8e8798 by task kworker/u5:2/6507 [ 39.488046] [ 39.489680] CPU: 0 PID: 6507 Comm: kworker/u5:2 Not tainted 4.19.136-syzkaller #0 [ 39.497296] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.506658] Workqueue: hci0 hci_rx_work [ 39.510629] Call Trace: [ 39.513223] dump_stack+0x1fc/0x2fe executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.516861] print_address_description.cold+0x54/0x219 [ 39.522143] kasan_report_error.cold+0x8a/0x1c7 [ 39.526816] ? hci_send_acl+0xad6/0xc70 [ 39.530789] __asan_report_load8_noabort+0x88/0x90 [ 39.535724] ? hci_send_acl+0xad6/0xc70 [ 39.539724] hci_send_acl+0xad6/0xc70 [ 39.543529] ? memcpy+0x35/0x50 [ 39.546810] ? l2cap_build_cmd+0x53e/0x6e0 [ 39.551053] l2cap_send_cmd+0x1bd/0x210 [ 39.555024] l2cap_recv_frame+0x6aa8/0xa550 [ 39.559372] ? mark_held_locks+0xf0/0xf0 [ 39.563438] ? kfree_skbmem+0xc1/0x140 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.567325] ? hci_event_packet+0x561/0x858f [ 39.571742] ? l2cap_ertm_init+0xa60/0xa60 [ 39.575986] ? __lock_acquire+0x6de/0x3ff0 [ 39.580228] ? lock_acquire+0x170/0x3c0 [ 39.584203] ? hci_rx_work+0x2e4/0xa90 [ 39.588098] ? hci_rx_work+0x426/0xa90 [ 39.591991] ? lock_downgrade+0x720/0x720 [ 39.596143] ? hci_rx_work+0x2e4/0xa90 [ 39.600034] ? __mutex_add_waiter+0x160/0x160 [ 39.604535] ? __mutex_unlock_slowpath+0xea/0x610 [ 39.609484] ? hci_conn_enter_active_mode+0x19c/0x2c0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.614677] l2cap_recv_acldata+0x80e/0x910 [ 39.619004] hci_rx_work+0x455/0xa90 [ 39.622754] process_one_work+0x864/0x1570 [ 39.627009] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 39.631691] worker_thread+0x64c/0x1130 [ 39.635680] ? __kthread_parkme+0xfd/0x1b0 [ 39.639922] ? process_one_work+0x1570/0x1570 [ 39.644425] kthread+0x30b/0x410 [ 39.647947] ? kthread_park+0x180/0x180 [ 39.651929] ret_from_fork+0x24/0x30 [ 39.655655] [ 39.657273] Allocated by task 1226: [ 39.660896] kmem_cache_alloc_trace+0x12f/0x380 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.665565] hci_chan_create+0x8e/0x310 [ 39.669553] l2cap_conn_add.part.0+0x18/0xc40 [ 39.674052] l2cap_connect_cfm+0x236/0xe70 [ 39.678288] hci_event_packet+0x3a31/0x858f [ 39.682610] hci_rx_work+0x46b/0xa90 [ 39.686325] process_one_work+0x864/0x1570 [ 39.690553] worker_thread+0x64c/0x1130 [ 39.694531] kthread+0x30b/0x410 [ 39.697902] ret_from_fork+0x24/0x30 [ 39.701604] [ 39.703219] Freed by task 6507: [ 39.706495] kfree+0xcc/0x210 [ 39.709597] hci_event_packet+0xf52/0x858f [ 39.713835] hci_rx_work+0x46b/0xa90 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.717548] process_one_work+0x864/0x1570 [ 39.721781] worker_thread+0x64c/0x1130 [ 39.725757] kthread+0x30b/0x410 [ 39.729141] ret_from_fork+0x24/0x30 [ 39.732853] [ 39.734477] The buggy address belongs to the object at ffff88809f8e8780 [ 39.734477] which belongs to the cache kmalloc-128 of size 128 [ 39.747134] The buggy address is located 24 bytes inside of [ 39.747134] 128-byte region [ffff88809f8e8780, ffff88809f8e8800) [ 39.758916] The buggy address belongs to the page: executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.763845] page:ffffea00027e3a00 count:1 mapcount:0 mapping:ffff88812c39c640 index:0x0 [ 39.771983] flags: 0xfffe0000000100(slab) [ 39.776135] raw: 00fffe0000000100 ffffea0002806bc8 ffffea00027ed848 ffff88812c39c640 [ 39.784016] raw: 0000000000000000 ffff88809f8e8000 0000000100000015 0000000000000000 [ 39.791889] page dumped because: kasan: bad access detected [ 39.797588] [ 39.799205] Memory state around the buggy address: [ 39.804130] ffff88809f8e8680: 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 [ 39.811501] ffff88809f8e8700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 39.818870] >ffff88809f8e8780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 39.826224] ^ [ 39.830370] ffff88809f8e8800: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 [ 39.837736] ffff88809f8e8880: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 39.845089] ================================================================== [ 39.852437] Disabling lock debugging due to kernel taint executing program executing program executing program executing program executing program executing program executing program [ 39.866601] Kernel panic - not syncing: panic_on_warn set ... [ 39.866601] [ 39.866615] CPU: 0 PID: 6507 Comm: kworker/u5:2 Tainted: G B 4.19.136-syzkaller #0 [ 39.866621] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.866635] Workqueue: hci0 hci_rx_work [ 39.896272] Call Trace: [ 39.898858] dump_stack+0x1fc/0x2fe [ 39.902485] panic+0x26a/0x50e [ 39.905674] ? __warn_printk+0xf3/0xf3 [ 39.909559] ? preempt_schedule_common+0x45/0xc0 [ 39.914322] ? ___preempt_schedule+0x16/0x18 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.918735] ? trace_hardirqs_on+0x55/0x210 [ 39.923069] kasan_end_report+0x43/0x49 [ 39.927037] kasan_report_error.cold+0xa7/0x1c7 [ 39.931696] ? hci_send_acl+0xad6/0xc70 [ 39.935663] __asan_report_load8_noabort+0x88/0x90 [ 39.940584] ? hci_send_acl+0xad6/0xc70 [ 39.944549] hci_send_acl+0xad6/0xc70 [ 39.948350] ? memcpy+0x35/0x50 [ 39.951632] ? l2cap_build_cmd+0x53e/0x6e0 [ 39.955860] l2cap_send_cmd+0x1bd/0x210 [ 39.959828] l2cap_recv_frame+0x6aa8/0xa550 [ 39.964142] ? mark_held_locks+0xf0/0xf0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 39.968210] ? kfree_skbmem+0xc1/0x140 [ 39.972087] ? hci_event_packet+0x561/0x858f [ 39.976513] ? l2cap_ertm_init+0xa60/0xa60 [ 39.980746] ? __lock_acquire+0x6de/0x3ff0 [ 39.984987] ? lock_acquire+0x170/0x3c0 [ 39.988952] ? hci_rx_work+0x2e4/0xa90 [ 39.992840] ? hci_rx_work+0x426/0xa90 [ 39.996734] ? lock_downgrade+0x720/0x720 [ 40.000907] ? hci_rx_work+0x2e4/0xa90 [ 40.004786] ? __mutex_add_waiter+0x160/0x160 [ 40.009270] ? __mutex_unlock_slowpath+0xea/0x610 [ 40.014220] ? hci_conn_enter_active_mode+0x19c/0x2c0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 40.019415] l2cap_recv_acldata+0x80e/0x910 [ 40.023730] hci_rx_work+0x455/0xa90 [ 40.027436] process_one_work+0x864/0x1570 [ 40.031675] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 40.036350] worker_thread+0x64c/0x1130 [ 40.040330] ? __kthread_parkme+0xfd/0x1b0 [ 40.044553] ? process_one_work+0x1570/0x1570 [ 40.049033] kthread+0x30b/0x410 [ 40.052394] ? kthread_park+0x180/0x180 [ 40.063048] ret_from_fork+0x24/0x30 [ 40.068014] Kernel Offset: disabled [ 40.071627] Rebooting in 86400 seconds..