------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 16 at lib/refcount.c:28 refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Modules linked in:
CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-syzkaller-09073-g9f16d5e6f220 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Code: a0 0f 61 8c e8 57 dc 95 fc 90 0f 0b 90 90 eb 99 e8 3b 36 d5 fc c6 05 0e d4 47 0b 01 90 48 c7 c7 00 10 61 8c e8 37 dc 95 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 18 36 d5 fc c6 05 e8 d3 47 0b 01 90
RSP: 0018:ffffc90000157480 EFLAGS: 00010246
RAX: e53b0df9a8c41700 RBX: ffff888024906c24 RCX: ffff88801cadda00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff815688b2 R09: fffffbfff1cfa8a0
R10: dffffc0000000000 R11: fffffbfff1cfa8a0 R12: ffff888022b5c400
R13: ffff888024906c24 R14: ffff888022b5c400 R15: ffff888066790618
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c39dd5e CR3: 000000006f972000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 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+0x2c7/0x980 kernel/softirq.c:554
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943
 smpboot_thread_fn+0x546/0xa30 kernel/smpboot.c:164
 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>