[ 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 '10.128.0.110' (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 syzkaller login: [ 36.427342] ================================================================== [ 36.434892] BUG: KASAN: use-after-free in ex_handler_refcount+0x18f/0x1c0 [ 36.441844] Write of size 4 at addr ffff8880ae2413d8 by task syz-executor762/8130 [ 36.449459] [ 36.451097] CPU: 0 PID: 8130 Comm: syz-executor762 Not tainted 4.19.187-syzkaller #0 [ 36.458983] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 36.468343] Call Trace: [ 36.470941] dump_stack+0x1fc/0x2ef [ 36.474583] print_address_description.cold+0x54/0x219 [ 36.479872] kasan_report_error.cold+0x8a/0x1b9 [ 36.484552] ? ex_handler_refcount+0x18f/0x1c0 [ 36.489181] __asan_report_store4_noabort+0x88/0x90 [ 36.494237] ? ex_handler_refcount+0x18f/0x1c0 [ 36.499331] ex_handler_refcount+0x18f/0x1c0 [ 36.503899] ? ex_handler_clear_fs+0xb0/0xb0 [ 36.508316] fixup_exception+0x8a/0xd0 [ 36.512215] do_trap+0x61/0x250 [ 36.515508] do_error_trap+0x15d/0x310 [ 36.519408] ? math_error+0x310/0x310 [ 36.523225] ? __noinstr_text_end+0x7617/0x77e7 [ 36.527914] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 36.532777] invalid_op+0x14/0x20 [ 36.536255] RIP: 0010:__noinstr_text_end+0x7617/0x77e7 [ 36.541551] Code: 8d 0e 0f 0b 48 8d 8d 80 00 00 00 0f 0b 48 8d 8d 80 00 00 00 0f 0b 48 8d 8b 80 00 00 00 0f 0b 49 8d 4c 24 18 0f 0b 48 8d 4d 18 <0f> 0b 49 8d 8d 80 00 00 00 0f 0b 49 8d 4d 00 0f 0b 48 8d 8b e4 00 [ 36.560458] RSP: 0018:ffff8880950afbc0 EFLAGS: 00010297 [ 36.565825] RAX: ffff888095cda2c0 RBX: 0000000000000004 RCX: ffff8880ae2413d8 [ 36.573099] RDX: 0000000000000000 RSI: ffffffff87dcb8f8 RDI: ffff8880ae2413c0 [ 36.580378] RBP: ffff8880ae2413c0 R08: 0000000000000000 R09: 0000000000000000 [ 36.587658] R10: 0000000000000001 R11: 0000000000000000 R12: ffff888095335680 [ 36.594934] R13: ffff888095335680 R14: ffff8880ae2413c0 R15: ffff8880b5bc3e20 [ 36.602241] ? nfc_llcp_local_put+0x18/0x1b0 [ 36.606650] ? nfc_llcp_sock_free+0x220/0x220 [ 36.611146] llcp_sock_destruct+0x7b/0x140 [ 36.615391] __sk_destruct+0x4b/0x8a0 [ 36.619206] __sk_free+0x165/0x3b0 [ 36.622748] sk_free+0x3b/0x50 [ 36.625942] llcp_sock_release+0x37a/0x520 [ 36.630192] __sock_release+0xcd/0x2a0 [ 36.634091] ? __sock_release+0x2a0/0x2a0 [ 36.638260] sock_close+0x15/0x20 [ 36.641750] __fput+0x2ce/0x890 [ 36.645076] task_work_run+0x148/0x1c0 [ 36.648987] do_exit+0xbf3/0x2be0 [ 36.652458] ? lock_downgrade+0x720/0x720 [ 36.656642] ? mm_update_next_owner+0x650/0x650 [ 36.661322] ? up_read+0x17/0x110 [ 36.664787] ? __do_page_fault+0x180/0xd60 [ 36.669035] do_group_exit+0x125/0x310 [ 36.672937] __x64_sys_exit_group+0x3a/0x50 [ 36.677270] do_syscall_64+0xf9/0x620 [ 36.681119] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 36.686315] RIP: 0033:0x43e989 [ 36.689542] Code: 00 49 c7 c0 c0 ff ff ff be e7 00 00 00 ba 3c 00 00 00 eb 12 0f 1f 44 00 00 89 d0 0f 05 48 3d 00 f0 ff ff 77 1c f4 89 f0 0f 05 <48> 3d 00 f0 ff ff 76 e7 f7 d8 64 41 89 00 eb df 0f 1f 80 00 00 00 [ 36.709059] RSP: 002b:00007ffef4b14b68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 36.716772] RAX: ffffffffffffffda RBX: 00000000004b02f0 RCX: 000000000043e989 [ 36.724046] RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 [ 36.731492] RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000000000001 [ 36.738756] R10: 0000000000080800 R11: 0000000000000246 R12: 00000000004b02f0 [ 36.746018] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 [ 36.753301] [ 36.754924] Allocated by task 1: [ 36.758288] kmem_cache_alloc_trace+0x12f/0x380 [ 36.763018] nfc_llcp_register_device+0x45/0x9b0 [ 36.767765] nfc_register_device+0x6d/0x360 [ 36.772095] nfcsim_device_new+0x333/0x5af [ 36.776338] nfcsim_init+0x71/0x14d [ 36.779970] do_one_initcall+0xf1/0x740 [ 36.783941] kernel_init_freeable+0x9a6/0xa98 [ 36.788428] kernel_init+0xd/0x1b6 [ 36.791974] ret_from_fork+0x24/0x30 [ 36.795680] [ 36.797304] Freed by task 8132: [ 36.800587] kfree+0xcc/0x210 [ 36.803701] nfc_llcp_local_put+0x155/0x1b0 [ 36.808028] llcp_sock_destruct+0x7b/0x140 [ 36.812269] __sk_destruct+0x4b/0x8a0 [ 36.816073] __sk_free+0x165/0x3b0 [ 36.819615] sk_free+0x3b/0x50 [ 36.822819] llcp_sock_release+0x37a/0x520 [ 36.827058] __sock_release+0xcd/0x2a0 [ 36.830974] sock_close+0x15/0x20 [ 36.834433] __fput+0x2ce/0x890 [ 36.837712] task_work_run+0x148/0x1c0 [ 36.841594] do_exit+0xbf3/0x2be0 [ 36.845074] do_group_exit+0x125/0x310 [ 36.848966] __x64_sys_exit_group+0x3a/0x50 [ 36.853292] do_syscall_64+0xf9/0x620 [ 36.857099] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 36.862282] [ 36.863930] The buggy address belongs to the object at ffff8880ae2413c0 [ 36.863930] which belongs to the cache kmalloc-2048 of size 2048 [ 36.876768] The buggy address is located 24 bytes inside of [ 36.876768] 2048-byte region [ffff8880ae2413c0, ffff8880ae241bc0) [ 36.888645] The buggy address belongs to the page: [ 36.893581] page:ffffea0002b89000 count:1 mapcount:0 mapping:ffff88813bff0c40 index:0x0 compound_mapcount: 0 [ 36.903572] flags: 0xfff00000008100(slab|head) [ 36.908149] raw: 00fff00000008100 ffffea0002b85788 ffffea0002b8a188 ffff88813bff0c40 [ 36.916027] raw: 0000000000000000 ffff8880ae2402c0 0000000100000003 0000000000000000 [ 36.923886] page dumped because: kasan: bad access detected [ 36.929581] [ 36.931206] Memory state around the buggy address: [ 36.936152] ffff8880ae241280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 36.943504] ffff8880ae241300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 36.950866] >ffff8880ae241380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 36.958226] ^ [ 36.964471] ffff8880ae241400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 36.971852] ffff8880ae241480: fb fb fb fb fb fb fb fb 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 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 36.979209] ================================================================== [ 36.986568] Disabling lock debugging due to kernel taint executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.077815] Kernel panic - not syncing: panic_on_warn set ... [ 37.077815] [ 37.085229] CPU: 1 PID: 8130 Comm: syz-executor762 Tainted: G B 4.19.187-syzkaller #0 [ 37.094495] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.103845] Call Trace: [ 37.106437] dump_stack+0x1fc/0x2ef [ 37.110070] panic+0x26a/0x50e [ 37.113269] ? __warn_printk+0xf3/0xf3 [ 37.117168] ? preempt_schedule_common+0x45/0xc0 [ 37.121929] ? ___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 executing program [ 37.126347] ? trace_hardirqs_on+0x55/0x210 [ 37.130678] kasan_end_report+0x43/0x49 [ 37.134656] kasan_report_error.cold+0xa7/0x1b9 [ 37.139330] ? ex_handler_refcount+0x18f/0x1c0 [ 37.143918] __asan_report_store4_noabort+0x88/0x90 [ 37.148937] ? ex_handler_refcount+0x18f/0x1c0 [ 37.153525] ex_handler_refcount+0x18f/0x1c0 [ 37.157935] ? ex_handler_clear_fs+0xb0/0xb0 [ 37.162344] fixup_exception+0x8a/0xd0 [ 37.166267] do_trap+0x61/0x250 [ 37.169642] do_error_trap+0x15d/0x310 [ 37.173534] ? math_error+0x310/0x310 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 [ 37.177346] ? __noinstr_text_end+0x7617/0x77e7 [ 37.182049] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 37.186899] invalid_op+0x14/0x20 [ 37.190361] RIP: 0010:__noinstr_text_end+0x7617/0x77e7 [ 37.195644] Code: 8d 0e 0f 0b 48 8d 8d 80 00 00 00 0f 0b 48 8d 8d 80 00 00 00 0f 0b 48 8d 8b 80 00 00 00 0f 0b 49 8d 4c 24 18 0f 0b 48 8d 4d 18 <0f> 0b 49 8d 8d 80 00 00 00 0f 0b 49 8d 4d 00 0f 0b 48 8d 8b e4 00 [ 37.214544] RSP: 0018:ffff8880950afbc0 EFLAGS: 00010297 [ 37.219908] RAX: ffff888095cda2c0 RBX: 0000000000000004 RCX: ffff8880ae2413d8 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.227178] RDX: 0000000000000000 RSI: ffffffff87dcb8f8 RDI: ffff8880ae2413c0 [ 37.234450] RBP: ffff8880ae2413c0 R08: 0000000000000000 R09: 0000000000000000 [ 37.241725] R10: 0000000000000001 R11: 0000000000000000 R12: ffff888095335680 [ 37.248999] R13: ffff888095335680 R14: ffff8880ae2413c0 R15: ffff8880b5bc3e20 [ 37.256284] ? nfc_llcp_local_put+0x18/0x1b0 [ 37.260707] ? nfc_llcp_sock_free+0x220/0x220 [ 37.265208] llcp_sock_destruct+0x7b/0x140 [ 37.269459] __sk_destruct+0x4b/0x8a0 [ 37.273267] __sk_free+0x165/0x3b0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.276809] sk_free+0x3b/0x50 [ 37.280009] llcp_sock_release+0x37a/0x520 [ 37.284272] __sock_release+0xcd/0x2a0 [ 37.288170] ? __sock_release+0x2a0/0x2a0 [ 37.292323] sock_close+0x15/0x20 [ 37.295783] __fput+0x2ce/0x890 [ 37.299078] task_work_run+0x148/0x1c0 [ 37.302980] do_exit+0xbf3/0x2be0 [ 37.306444] ? lock_downgrade+0x720/0x720 [ 37.310602] ? mm_update_next_owner+0x650/0x650 [ 37.315286] ? up_read+0x17/0x110 [ 37.318748] ? __do_page_fault+0x180/0xd60 [ 37.322990] do_group_exit+0x125/0x310 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 [ 37.326890] __x64_sys_exit_group+0x3a/0x50 [ 37.331223] do_syscall_64+0xf9/0x620 [ 37.335030] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 37.340222] RIP: 0033:0x43e989 [ 37.343421] Code: 00 49 c7 c0 c0 ff ff ff be e7 00 00 00 ba 3c 00 00 00 eb 12 0f 1f 44 00 00 89 d0 0f 05 48 3d 00 f0 ff ff 77 1c f4 89 f0 0f 05 <48> 3d 00 f0 ff ff 76 e7 f7 d8 64 41 89 00 eb df 0f 1f 80 00 00 00 [ 37.362455] RSP: 002b:00007ffef4b14b68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 37.370170] RAX: ffffffffffffffda RBX: 00000000004b02f0 RCX: 000000000043e989 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 37.377473] RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 [ 37.384746] RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000000000001 [ 37.392015] R10: 0000000000080800 R11: 0000000000000246 R12: 00000000004b02f0 [ 37.399284] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 [ 37.407156] Kernel Offset: disabled [ 37.410807] Rebooting in 86400 seconds..