------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 139 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0 lib/refcount.c:25 Modules linked in: CPU: 1 PID: 139 Comm: kworker/1:2 Not tainted 5.17.0-rc5-syzkaller-00306-g2293be58d6a1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events sco_sock_timeout RIP: 0010:refcount_warn_saturate+0x169/0x1e0 lib/refcount.c:25 Code: 09 31 ff 89 de e8 b7 95 99 fd 84 db 0f 85 36 ff ff ff e8 2a 93 99 fd 48 c7 c7 20 08 06 8a c6 05 c1 69 a0 09 01 e8 3e b4 28 05 <0f> 0b e9 17 ff ff ff e8 0b 93 99 fd 0f b6 1d a6 69 a0 09 31 ff 89 RSP: 0018:ffffc9000279fce8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff8880182d1d00 RSI: ffffffff815fe288 RDI: fffff520004f3f8f RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff815f891e R11: 0000000000000000 R12: ffff88807aae5008 R13: ffff88801a229080 R14: ffff8880182b4000 R15: ffff8880b9d39480 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcfdc1fb1b8 CR3: 000000000b88e000 CR4: 0000000000350ee0 Call Trace: __refcount_add include/linux/refcount.h:199 [inline] __refcount_inc include/linux/refcount.h:250 [inline] refcount_inc include/linux/refcount.h:267 [inline] sock_hold include/net/sock.h:712 [inline] sco_sock_timeout+0x216/0x290 net/bluetooth/sco.c:89 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295