[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.4' (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 syzkaller login: [ 50.669447] audit: type=1400 audit(1596736917.306:8): avc: denied { execmem } for pid=6466 comm="syz-executor264" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 50.907308] ================================================================== [ 50.914876] BUG: KASAN: use-after-free in ex_handler_refcount+0x18f/0x1c0 [ 50.921819] Write of size 4 at addr ffff8880a0df36d8 by task kworker/1:2/2884 [ 50.929089] [ 50.930716] CPU: 1 PID: 2884 Comm: kworker/1:2 Not tainted 4.19.137-syzkaller #0 [ 50.938239] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.947683] Workqueue: events do_enable_set [ 50.951991] Call Trace: [ 50.954585] dump_stack+0x1fc/0x2fe [ 50.958211] print_address_description.cold+0x54/0x219 [ 50.963910] kasan_report_error.cold+0x8a/0x1c7 [ 50.968587] ? ex_handler_refcount+0x18f/0x1c0 [ 50.973336] __asan_report_store4_noabort+0x88/0x90 [ 50.978346] ? ex_handler_refcount+0x18f/0x1c0 [ 50.982921] ex_handler_refcount+0x18f/0x1c0 [ 50.987325] ? ex_handler_clear_fs+0xb0/0xb0 [ 50.991727] fixup_exception+0x8a/0xc3 [ 50.995609] do_trap+0x61/0x250 [ 50.998881] do_error_trap+0x15d/0x310 [ 51.002772] ? math_error+0x310/0x310 [ 51.006572] ? csum_partial_copy_generic+0x607f/0x7811 [ 51.011849] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 51.016692] invalid_op+0x14/0x20 [ 51.020166] RIP: 0010:csum_partial_copy_generic+0x607f/0x7811 [ 51.026041] Code: 49 8d 8c 24 80 00 00 00 0f 0b 48 8d 8d 80 00 00 00 0f 0b 48 8d 8d 80 00 00 00 0f 0b 49 8d 8c 24 b8 02 00 00 0f 0b 48 8d 4d 18 <0f> 0b 48 8d 8d b8 02 00 00 0f 0b 48 8d 4b 18 0f 0b 48 8d 8d 80 00 [ 51.044932] RSP: 0018:ffff88809e1afc20 EFLAGS: 00010297 [ 51.050288] RAX: ffff88809e198380 RBX: 0000000000000001 RCX: ffff8880a0df36d8 [ 51.057557] RDX: 0000000000000000 RSI: ffffffff868150d0 RDI: ffff8880a0df36c0 [ 51.064826] RBP: ffff8880a0df36c0 R08: 0000000000000000 R09: 0000000000000008 [ 51.072138] R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880ae72bb10 [ 51.079403] R13: ffff88809e07f800 R14: ffff8880ae72bac0 R15: ffff8880a7d77280 [ 51.086678] ? l2cap_chan_put+0x10/0x1c0 [ 51.090735] do_enable_set+0x4ef/0x975 [ 51.094616] ? process_one_work+0x77b/0x1570 [ 51.099069] ? chan_recv_cb+0xa70/0xa70 [ 51.103037] ? check_preemption_disabled+0x41/0x280 [ 51.108056] process_one_work+0x864/0x1570 [ 51.112288] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 51.117019] worker_thread+0x64c/0x1130 [ 51.120995] ? __kthread_parkme+0xfd/0x1b0 [ 51.125222] ? process_one_work+0x1570/0x1570 [ 51.129708] kthread+0x30b/0x410 [ 51.133070] ? kthread_park+0x180/0x180 [ 51.137111] ret_from_fork+0x24/0x30 [ 51.140820] [ 51.142437] Allocated by task 6414: [ 51.146060] kmem_cache_alloc_trace+0x12f/0x380 [ 51.150852] l2cap_chan_create+0x40/0x380 [ 51.155078] do_enable_set+0x525/0x975 [ 51.158955] process_one_work+0x864/0x1570 [ 51.163177] worker_thread+0x64c/0x1130 [ 51.167142] kthread+0x30b/0x410 [ 51.170500] ret_from_fork+0x24/0x30 [ 51.174241] [ 51.175860] Freed by task 6414: [ 51.179132] kfree+0xcc/0x210 [ 51.182230] l2cap_chan_put+0x16b/0x1c0 [ 51.186192] do_enable_set+0x4ef/0x975 [ 51.190154] process_one_work+0x864/0x1570 [ 51.194378] worker_thread+0x64c/0x1130 [ 51.198398] kthread+0x30b/0x410 [ 51.201754] ret_from_fork+0x24/0x30 [ 51.205451] [ 51.207071] The buggy address belongs to the object at ffff8880a0df36c0 [ 51.207071] which belongs to the cache kmalloc-2048 of size 2048 [ 51.219897] The buggy address is located 24 bytes inside of [ 51.219897] 2048-byte region [ffff8880a0df36c0, ffff8880a0df3ec0) [ 51.231797] The buggy address belongs to the page: [ 51.236721] page:ffffea0002837c80 count:1 mapcount:0 mapping:ffff88812c39cc40 index:0x0 compound_mapcount: 0 [ 51.246673] flags: 0xfffe0000008100(slab|head) [ 51.251276] raw: 00fffe0000008100 ffffea0002831008 ffffea000282e288 ffff88812c39cc40 [ 51.259149] raw: 0000000000000000 ffff8880a0df25c0 0000000100000003 0000000000000000 [ 51.267017] page dumped because: kasan: bad access detected [ 51.272712] [ 51.274328] Memory state around the buggy address: [ 51.279246] ffff8880a0df3580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 51.286637] ffff8880a0df3600: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 51.293987] >ffff8880a0df3680: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 51.301334] ^ executing program executing program executing program executing program executing program [ 51.307613] ffff8880a0df3700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 51.314965] ffff8880a0df3780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 51.322310] ================================================================== [ 51.329828] Disabling lock debugging due to kernel taint [ 51.342592] Kernel panic - not syncing: panic_on_warn set ... [ 51.342592] [ 51.350081] CPU: 1 PID: 2884 Comm: kworker/1:2 Tainted: G B 4.19.137-syzkaller #0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 51.359095] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.368463] Workqueue: events do_enable_set [ 51.372788] Call Trace: [ 51.375389] dump_stack+0x1fc/0x2fe [ 51.379028] panic+0x26a/0x50e [ 51.382228] ? __warn_printk+0xf3/0xf3 [ 51.386126] ? preempt_schedule_common+0x45/0xc0 [ 51.390980] ? ___preempt_schedule+0x16/0x18 [ 51.395401] ? trace_hardirqs_on+0x55/0x210 [ 51.399832] kasan_end_report+0x43/0x49 [ 51.403915] kasan_report_error.cold+0xa7/0x1c7 [ 51.409038] ? ex_handler_refcount+0x18f/0x1c0 [ 51.413631] __asan_report_store4_noabort+0x88/0x90 [ 51.418661] ? ex_handler_refcount+0x18f/0x1c0 [ 51.423254] ex_handler_refcount+0x18f/0x1c0 [ 51.427847] ? ex_handler_clear_fs+0xb0/0xb0 [ 51.432263] fixup_exception+0x8a/0xc3 [ 51.436161] do_trap+0x61/0x250 [ 51.439576] do_error_trap+0x15d/0x310 [ 51.443473] ? math_error+0x310/0x310 [ 51.447282] ? csum_partial_copy_generic+0x607f/0x7811 [ 51.452658] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 51.457600] invalid_op+0x14/0x20 [ 51.461065] RIP: 0010:csum_partial_copy_generic+0x607f/0x7811 [ 51.466958] Code: 49 8d 8c 24 80 00 00 00 0f 0b 48 8d 8d 80 00 00 00 0f 0b 48 8d 8d 80 00 00 00 0f 0b 49 8d 8c 24 b8 02 00 00 0f 0b 48 8d 4d 18 <0f> 0b 48 8d 8d b8 02 00 00 0f 0b 48 8d 4b 18 0f 0b 48 8d 8d 80 00 [ 51.485982] RSP: 0018:ffff88809e1afc20 EFLAGS: 00010297 [ 51.491357] RAX: ffff88809e198380 RBX: 0000000000000001 RCX: ffff8880a0df36d8 [ 51.498637] RDX: 0000000000000000 RSI: ffffffff868150d0 RDI: ffff8880a0df36c0 [ 51.506036] RBP: ffff8880a0df36c0 R08: 0000000000000000 R09: 0000000000000008 [ 51.513398] R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880ae72bb10 [ 51.520676] R13: ffff88809e07f800 R14: ffff8880ae72bac0 R15: ffff8880a7d77280 [ 51.527972] ? l2cap_chan_put+0x10/0x1c0 [ 51.532052] do_enable_set+0x4ef/0x975 [ 51.536038] ? process_one_work+0x77b/0x1570 [ 51.540458] ? chan_recv_cb+0xa70/0xa70 [ 51.544440] ? check_preemption_disabled+0x41/0x280 [ 51.549465] process_one_work+0x864/0x1570 [ 51.553717] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 51.558411] worker_thread+0x64c/0x1130 [ 51.562399] ? __kthread_parkme+0xfd/0x1b0 [ 51.566640] ? process_one_work+0x1570/0x1570 [ 51.571288] kthread+0x30b/0x410 [ 51.574664] ? kthread_park+0x180/0x180 [ 51.578651] ret_from_fork+0x24/0x30 [ 51.583940] Kernel Offset: disabled [ 51.587564] Rebooting in 86400 seconds..