------------[ cut here ]------------ refcount_t: increment on 0; use-after-free. WARNING: CPU: 0 PID: 9904 at lib/refcount.c:153 refcount_inc_checked lib/refcount.c:153 [inline] WARNING: CPU: 0 PID: 9904 at lib/refcount.c:153 refcount_inc_checked+0x61/0x70 lib/refcount.c:151 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 9904 Comm: syz-executor905 Not tainted 4.19.36 #4 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 panic+0x263/0x51d kernel/panic.c:185 __warn.cold+0x20/0x54 kernel/panic.c:540 report_bug+0x263/0x2b0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] fixup_bug arch/x86/kernel/traps.c:173 [inline] do_error_trap+0x204/0x360 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:997 RIP: 0010:refcount_inc_checked lib/refcount.c:153 [inline] RIP: 0010:refcount_inc_checked+0x61/0x70 lib/refcount.c:151 Code: 1d 49 4d 12 06 31 ff 89 de e8 2b 9f 47 fe 84 db 75 dd e8 e2 9d 47 fe 48 c7 c7 c0 84 81 87 c6 05 29 4d 12 06 01 e8 fd 79 1b fe <0f> 0b eb c1 90 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 RSP: 0018:ffff88808dd27928 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8155df26 RDI: ffffed1011ba4f17 RBP: ffff88808dd27938 R08: ffff8880811922c0 R09: ffffed1015d03ee3 R10: ffffed1015d03ee2 R11: ffff8880ae81f717 R12: ffff88821adf5978 R13: ffff888098bbe820 R14: ffff888098bbe818 R15: ffff88821adf58f8 kref_get include/linux/kref.h:47 [inline] kobject_get+0x66/0xc0 lib/kobject.c:613 kset_get include/linux/kobject.h:213 [inline] kobj_kset_join lib/kobject.c:186 [inline] kobject_add_internal lib/kobject.c:238 [inline] kobject_add_internal+0x14f/0x380 lib/kobject.c:217 kobject_add_varg lib/kobject.c:382 [inline] kobject_add+0x150/0x1c0 lib/kobject.c:426 class_dir_create_and_add drivers/base/core.c:1560 [inline] get_device_parent.isra.0+0x415/0x570 drivers/base/core.c:1615 device_add+0x2f4/0x1770 drivers/base/core.c:1871 hci_register_dev+0x304/0x880 net/bluetooth/hci_core.c:3198 __vhci_create_device+0x2d0/0x5a0 drivers/bluetooth/hci_vhci.c:139 vhci_create_device drivers/bluetooth/hci_vhci.c:163 [inline] vhci_get_user drivers/bluetooth/hci_vhci.c:219 [inline] vhci_write+0x2d6/0x470 drivers/bluetooth/hci_vhci.c:299 call_write_iter include/linux/fs.h:1811 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x58e/0x820 fs/read_write.c:487 vfs_write+0x20c/0x560 fs/read_write.c:549 ksys_write+0xea/0x1f0 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x441269 Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffea6596038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441269 RDX: 0000000000000002 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 000000000001021a R08: 00000000004002c8 R09: 00000000004002c8 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000401fe0 R13: 0000000000402070 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds..