------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 47 at lib/refcount.c:25 refcount_warn_saturate+0x13d/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 0 PID: 47 Comm: kworker/u4:2 Not tainted 5.10.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: qrtr_ns_handler qrtr_ns_worker
RIP: 0010:refcount_warn_saturate+0x13d/0x1a0 lib/refcount.c:25
Code: c7 20 19 ec 89 31 c0 e8 71 c4 84 fd 0f 0b eb a3 e8 98 af b4 fd c6 05 a4 d3 1a 09 01 48 c7 c7 c0 19 ec 89 31 c0 e8 53 c4 84 fd <0f> 0b eb 85 e8 7a af b4 fd c6 05 87 d3 1a 09 01 48 c7 c7 20 1a ec
RSP: 0018:ffffc90000eff9c0 EFLAGS: 00010046
RAX: 1d94e1b30bdd0f00 RBX: 0000000000000002 RCX: ffff888011488000
RDX: 0000000000000000 RSI: 0000000080000001 RDI: 0000000000000000
RBP: 0000000000000002 R08: ffffffff815d1792 R09: ffffed1017383fec
R10: ffffed1017383fec R11: 0000000000000000 R12: ffff888029e07098
R13: 1ffff1100255a2f6 R14: 0000000000000282 R15: ffff888029e07000
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004d0656 CR3: 000000004d93f000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __refcount_add include/linux/refcount.h:201 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 kref_get include/linux/kref.h:45 [inline]
 qrtr_node_acquire net/qrtr/qrtr.c:196 [inline]
 qrtr_node_lookup+0xc0/0xd0 net/qrtr/qrtr.c:389
 qrtr_send_resume_tx net/qrtr/qrtr.c:981 [inline]
 qrtr_recvmsg+0x429/0xa80 net/qrtr/qrtr.c:1044
 qrtr_ns_worker+0x164/0x5470 net/qrtr/ns.c:692
 process_one_work+0x789/0xfc0 kernel/workqueue.c:2272
 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2418
 kthread+0x36b/0x390 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296