------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 5963 at lib/refcount.c:28 refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Modules linked in:
CPU: 1 UID: 0 PID: 5963 Comm: kworker/u8:9 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: bat_events batadv_nc_worker
RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Code: e0 1e 5f 8c e8 87 c5 95 fc 90 0f 0b 90 90 eb 99 e8 2b 1e d5 fc c6 05 6d 2c 39 0b 01 90 48 c7 c7 40 1f 5f 8c e8 67 c5 95 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 08 1e d5 fc c6 05 47 2c 39 0b 01 90
RSP: 0018:ffffc90000a186c0 EFLAGS: 00010246
RAX: 4950cf3d4d284800 RBX: ffff888054717364 RCX: ffff888031339e00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff81601c02 R09: fffffbfff1cfa210
R10: dffffc0000000000 R11: fffffbfff1cfa210 R12: ffff888027193c00
R13: ffff888054717364 R14: ffff888027193c00 R15: ffff888055f76118
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020007000 CR3: 000000002852c000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 kfree_skb_reason include/linux/skbuff.h:1263 [inline]
 kfree_skb include/linux/skbuff.h:1272 [inline]
 j1939_session_skb_drop_old net/can/j1939/transport.c:347 [inline]
 j1939_xtp_rx_cts_one net/can/j1939/transport.c:1445 [inline]
 j1939_xtp_rx_cts+0x552/0xc70 net/can/j1939/transport.c:1484
 j1939_tp_cmd_recv net/can/j1939/transport.c:2089 [inline]
 j1939_tp_recv+0x8ae/0x1050 net/can/j1939/transport.c:2161
 j1939_can_recv+0x732/0xb20 net/can/j1939/main.c:108
 deliver net/can/af_can.c:573 [inline]
 can_rcv_filter+0x35b/0x7f0 net/can/af_can.c:607
 can_receive+0x327/0x480 net/can/af_can.c:664
 can_rcv+0x144/0x260 net/can/af_can.c:688
 __netif_receive_skb_one_core net/core/dev.c:5672 [inline]
 __netif_receive_skb+0x2e2/0x650 net/core/dev.c:5785
 process_backlog+0x662/0x15b0 net/core/dev.c:6117
 __napi_poll+0xcd/0x490 net/core/dev.c:6877
 napi_poll net/core/dev.c:6946 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:7068
 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:554
 do_softirq+0x11b/0x1e0 kernel/softirq.c:455
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 batadv_nc_purge_paths+0x312/0x3b0 net/batman-adv/network-coding.c:471
 batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>