------------[ cut here ]------------ refcount_t: increment on 0; use-after-free. WARNING: CPU: 1 PID: 30065 at lib/refcount.c:156 refcount_inc_checked lib/refcount.c:156 [inline] WARNING: CPU: 1 PID: 30065 at lib/refcount.c:156 refcount_inc_checked+0x61/0x70 lib/refcount.c:154 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 30065 Comm: syz-executor.3 Not tainted 5.1.0+ #1 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+0x2cb/0x65c kernel/panic.c:214 __warn.cold+0x20/0x45 kernel/panic.c:566 report_bug+0x263/0x2b0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:179 [inline] fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:972 RIP: 0010:refcount_inc_checked lib/refcount.c:156 [inline] RIP: 0010:refcount_inc_checked+0x61/0x70 lib/refcount.c:154 Code: 1d 20 5a 2a 06 31 ff 89 de e8 fb 6a 40 fe 84 db 75 dd e8 b2 69 40 fe 48 c7 c7 80 ca a1 87 c6 05 00 5a 2a 06 01 e8 0d 2c 13 fe <0f> 0b eb c1 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41 RSP: 0018:ffff88806c6478d8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000018cdc RSI: ffffffff815aec76 RDI: ffffed100d8c8f0d RBP: ffff88806c6478e8 R08: ffff88805ca2a180 R09: ffffed1015d26011 R10: ffffed1015d26010 R11: ffff8880ae930087 R12: ffff8880a7652c38 R13: ffff8880887ec620 R14: ffff8880887ec618 R15: ffff8880a7652bb8 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:1732 [inline] get_device_parent.isra.0+0x415/0x570 drivers/base/core.c:1787 device_add+0x2fd/0x18a0 drivers/base/core.c:2043 hci_register_dev+0x2e8/0x860 net/bluetooth/hci_core.c:3307 __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+0x2d0/0x470 drivers/bluetooth/hci_vhci.c:299 call_write_iter include/linux/fs.h:1866 [inline] new_sync_write+0x4c7/0x760 fs/read_write.c:474 __vfs_write+0xe4/0x110 fs/read_write.c:487 vfs_write+0x20c/0x580 fs/read_write.c:549 ksys_write+0x14f/0x2d0 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __ia32_sys_write+0x71/0xb0 fs/read_write.c:608 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x281/0xc98 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f16849 Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5d120cc EFLAGS: 00000296 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds..