------------[ cut here ]------------
refcount_t: increment on 0; use-after-free.
WARNING: CPU: 0 PID: 31858 at lib/refcount.c:153 refcount_inc_checked lib/refcount.c:153 [inline]
WARNING: CPU: 0 PID: 31858 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: 31858 Comm: syz-executor111 Not tainted 4.19.37 #5
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 6a 4b 12 06 31 ff 89 de e8 bb 9d 47 fe 84 db 75 dd e8 72 9c 47 fe 48 c7 c7 80 86 81 87 c6 05 4a 4b 12 06 01 e8 1d 76 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:ffff8880a8eb7390 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8155e196 RDI: ffffed10151d6e64
RBP: ffff8880a8eb73a0 R08: ffff8880803f0080 R09: ffffed1015d03ee3
R10: ffffed1015d03ee2 R11: ffff8880ae81f717 R12: ffff88821add19b8
R13: ffff888099825620 R14: ffff888099825618 R15: ffff88821add1938
 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
 __kernel_write+0x110/0x390 fs/read_write.c:506
 write_pipe_buf+0x15d/0x1f0 fs/splice.c:798
 splice_from_pipe_feed fs/splice.c:503 [inline]
 __splice_from_pipe+0x39a/0x7e0 fs/splice.c:627
 splice_from_pipe+0x108/0x170 fs/splice.c:662
 default_file_splice_write+0x3c/0x90 fs/splice.c:810
 do_splice_from fs/splice.c:852 [inline]
 direct_splice_actor+0x126/0x1a0 fs/splice.c:1019
 splice_direct_to_actor+0x2ea/0x890 fs/splice.c:974
 do_splice_direct+0x1da/0x2a0 fs/splice.c:1062
 do_sendfile+0x597/0xce0 fs/read_write.c:1446
 __do_sys_sendfile64 fs/read_write.c:1507 [inline]
 __se_sys_sendfile64 fs/read_write.c:1493 [inline]
 __x64_sys_sendfile64+0x1dd/0x220 fs/read_write.c:1493
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446839
Code: e8 0c 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 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5763124db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 0000000000446839
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffd5c0a03df R14: 00007f57631259c0 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..