------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 5274 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Modules linked in:
CPU: 0 UID: 0 PID: 5274 Comm: kworker/0:6 Not tainted 6.12.0-rc1-syzkaller-00046-g7ec462100ef9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Code: ff 89 de e8 78 1c fe fc 84 db 0f 85 66 ff ff ff e8 8b 1a fe fc c6 05 e0 7e b8 0b 01 90 48 c7 c7 40 4a d1 8b e8 17 03 bf fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 68 1a fe fc 0f b6 1d bb 7e b8 0b 31
RSP: 0018:ffffc90000007948 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff814e7329
RDX: ffff888032565a00 RSI: ffffffff814e7336 RDI: 0000000000000001
RBP: ffff88803012e4a4 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 00000000000505b8 R12: 0000000000000002
R13: 0000000000000000 R14: ffff88803012e4a4 R15: ffff88804f1db319
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002057eff8 CR3: 00000000629a6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__refcount_sub_and_test include/linux/refcount.h:275 [inline]
__refcount_dec_and_test include/linux/refcount.h:307 [inline]
refcount_dec_and_test include/linux/refcount.h:325 [inline]
skb_unref include/linux/skbuff.h:1232 [inline]
__sk_skb_reason_drop net/core/skbuff.c:1213 [inline]
sk_skb_reason_drop+0x183/0x1a0 net/core/skbuff.c:1241
kfree_skb_reason include/linux/skbuff.h:1262 [inline]
kfree_skb include/linux/skbuff.h:1271 [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+0x622/0xf50 net/can/j1939/transport.c:1484
j1939_tp_cmd_recv net/can/j1939/transport.c:2089 [inline]
j1939_tp_recv+0x568/0xf50 net/can/j1939/transport.c:2161
j1939_can_recv+0x78f/0xa50 net/can/j1939/main.c:108
deliver net/can/af_can.c:572 [inline]
can_rcv_filter+0x2a8/0x900 net/can/af_can.c:606
can_receive+0x320/0x5c0 net/can/af_can.c:663
can_rcv+0x1e2/0x280 net/can/af_can.c:687
__netif_receive_skb_one_core+0x1b1/0x1e0 net/core/dev.c:5662
__netif_receive_skb+0x1d/0x160 net/core/dev.c:5775
process_backlog+0x443/0x15f0 net/core/dev.c:6107
__napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6771
napi_poll net/core/dev.c:6840 [inline]
net_rx_action+0xa92/0x1010 net/core/dev.c:6962
handle_softirqs+0x213/0x8f0 kernel/softirq.c:554
do_softirq kernel/softirq.c:455 [inline]
do_softirq+0xb2/0xf0 kernel/softirq.c:442
__local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382
spin_unlock_bh include/linux/spinlock.h:396 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
nsim_dev_trap_report_work+0x870/0xc80 drivers/net/netdevsim/dev.c:850
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244