------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 10403 at lib/refcount.c:28 refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28 Modules linked in: CPU: 0 UID: 0 PID: 10403 Comm: kbnepd bnep0 Not tainted 6.14.0-rc1-syzkaller-00092-g011b03359038 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28 Code: 00 45 60 8c e8 17 4d 97 fc 90 0f 0b 90 90 eb 99 e8 9b a1 d6 fc c6 05 fa bb 1c 0b 01 90 48 c7 c7 60 45 60 8c e8 f7 4c 97 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 78 a1 d6 fc c6 05 d4 bb 1c 0b 01 90 RSP: 0018:ffffc9000e987720 EFLAGS: 00010246 RAX: 5b7d8ee7720fab00 RBX: ffff88803276fc78 RCX: ffff8880324e5a00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000003 R08: ffffffff81800c22 R09: fffffbfff1cfa588 R10: dffffc0000000000 R11: fffffbfff1cfa588 R12: ffff88803276fc60 R13: 1ffff110064edf8c R14: ffff88803276fc60 R15: ffffffff862ad220 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055557f299808 CR3: 000000002917e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __refcount_sub_and_test include/linux/refcount.h:275 [inline] __refcount_dec_and_test include/linux/refcount.h:307 [inline] refcount_dec_and_test include/linux/refcount.h:325 [inline] kref_put include/linux/kref.h:64 [inline] klist_dec_and_del+0x3ec/0x3f0 lib/klist.c:206 klist_put lib/klist.c:217 [inline] klist_del+0xa7/0x110 lib/klist.c:230 device_del+0x2c9/0x9b0 drivers/base/core.c:3831 unregister_netdevice_many_notify+0x19b4/0x1f10 net/core/dev.c:11855 unregister_netdevice_many net/core/dev.c:11883 [inline] unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11753 unregister_netdevice include/linux/netdevice.h:3335 [inline] unregister_netdev+0x21/0x30 net/core/dev.c:11903 bnep_session+0x2e3c/0x3030 net/bluetooth/bnep/core.c:525 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK>