------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 20470 at lib/refcount.c:25 refcount_warn_saturate+0x13d/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 1 PID: 20470 Comm: kworker/u4:17 Not tainted 5.10.0-rc3-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 a0 45 ec 89 31 c0 e8 b1 2e 84 fd 0f 0b eb a3 e8 38 1d b4 fd c6 05 8f 60 1a 09 01 48 c7 c7 40 46 ec 89 31 c0 e8 93 2e 84 fd <0f> 0b eb 85 e8 1a 1d b4 fd c6 05 72 60 1a 09 01 48 c7 c7 a0 46 ec
RSP: 0018:ffffc90002a3f9c0 EFLAGS: 00010046
RAX: 848fd73cb1ed0500 RBX: 0000000000000002 RCX: ffff888063854ec0
RDX: 0000000000000000 RSI: 0000000080000001 RDI: 0000000000000000
RBP: 0000000000000002 R08: ffffffff815d1882 R09: ffffed10173a3fec
R10: ffffed10173a3fec R11: 0000000000000000 R12: ffff888021d61098
R13: 1ffff1100cfebb6e R14: 0000000000000282 R15: ffff888021d61000
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000016a5374 CR3: 00000000509cf000 CR4: 00000000001526e0
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