------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 25 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0 lib/refcount.c:25
Modules linked in:
CPU: 1 PID: 25 Comm: kworker/u4:1 Tainted: G        W         5.13.0-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+0x169/0x1e0 lib/refcount.c:25
Code: 0a 31 ff 89 de e8 47 73 a2 fd 84 db 0f 85 36 ff ff ff e8 fa 6c a2 fd 48 c7 c7 a0 2d e3 89 c6 05 02 b5 03 0a 01 e8 24 1a 0c 05 <0f> 0b e9 17 ff ff ff e8 db 6c a2 fd 0f b6 1d e7 b4 03 0a 31 ff 89
RSP: 0018:ffffc90000dffa00 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888015da1c40 RSI: ffffffff815d7235 RDI: fffff520001bff32
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815d109e R11: 0000000000000000 R12: ffff8881441d0000
R13: ffff888021ffa800 R14: ffff888035bb8df0 R15: ffff888035bb8df4
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffea272d828 CR3: 00000000176fa000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
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]
 kref_get include/linux/kref.h:45 [inline]
 qrtr_node_acquire net/qrtr/qrtr.c:202 [inline]
 qrtr_node_lookup net/qrtr/qrtr.c:398 [inline]
 qrtr_send_resume_tx net/qrtr/qrtr.c:995 [inline]
 qrtr_recvmsg+0x85a/0x990 net/qrtr/qrtr.c:1063
 sock_recvmsg_nosec net/socket.c:936 [inline]
 sock_recvmsg net/socket.c:954 [inline]
 sock_recvmsg net/socket.c:950 [inline]
 kernel_recvmsg+0x110/0x160 net/socket.c:979
 qrtr_ns_worker+0x15a/0x1710 net/qrtr/ns.c:684
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295