------------[ cut here ]------------
WARNING: CPU: 1 PID: 76 at lib/refcount.c:28 refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28
refcount_t: underflow; use-after-free.
Modules linked in:
Kernel panic - not syncing: kernel: panic_on_warn set ...
CPU: 1 UID: 0 PID: 76 Comm: kworker/u10:1 Not tainted 6.12.0-syzkaller #0
Hardware name: ARM-Versatile Express
Workqueue: events_unbound nsim_dev_trap_report_work
Call trace: frame pointer underflow
[<819a01f8>] (dump_backtrace) from [<819a02f4>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:00000000 r6:82622f84 r5:00000000 r4:8203e950
[<819a02dc>] (show_stack) from [<819be7c0>] (__dump_stack lib/dump_stack.c:94 [inline])
[<819a02dc>] (show_stack) from [<819be7c0>] (dump_stack_lvl+0x54/0x7c lib/dump_stack.c:120)
[<819be76c>] (dump_stack_lvl) from [<819be800>] (dump_stack+0x18/0x1c lib/dump_stack.c:129)
 r5:00000000 r4:82871d18
[<819be7e8>] (dump_stack) from [<819a0e20>] (panic+0x120/0x374 kernel/panic.c:354)
[<819a0d00>] (panic) from [<802420d8>] (check_panic_on_warn kernel/panic.c:243 [inline])
[<819a0d00>] (panic) from [<802420d8>] (get_taint+0x0/0x1c kernel/panic.c:238)
 r3:8260c604 r2:00000001 r1:82026cdc r0:8202e790
 r7:80843b38
[<80242064>] (check_panic_on_warn) from [<8024223c>] (__warn+0x80/0x188 kernel/panic.c:748)
[<802421bc>] (__warn) from [<8024252c>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:783)
 r8:00000009 r7:8208d4bc r6:df805c94 r5:82f01800 r4:00000000
[<80242348>] (warn_slowpath_fmt) from [<80843b38>] (refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28)
 r10:20000113 r9:850d6d5c r8:83c7a480 r7:00000000 r6:8182fd94 r5:00000002
 r4:83c7a480
[<808439fc>] (refcount_warn_saturate) from [<8149f308>] (__refcount_sub_and_test include/linux/refcount.h:275 [inline])
[<808439fc>] (refcount_warn_saturate) from [<8149f308>] (__refcount_dec_and_test include/linux/refcount.h:307 [inline])
[<808439fc>] (refcount_warn_saturate) from [<8149f308>] (refcount_dec_and_test include/linux/refcount.h:325 [inline])
[<808439fc>] (refcount_warn_saturate) from [<8149f308>] (skb_unref include/linux/skbuff.h:1232 [inline])
[<808439fc>] (refcount_warn_saturate) from [<8149f308>] (__sk_skb_reason_drop net/core/skbuff.c:1213 [inline])
[<808439fc>] (refcount_warn_saturate) from [<8149f308>] (sk_skb_reason_drop+0x1d8/0x248 net/core/skbuff.c:1241)
[<8149f130>] (sk_skb_reason_drop) from [<8182fd94>] (kfree_skb_reason include/linux/skbuff.h:1262 [inline])
[<8149f130>] (sk_skb_reason_drop) from [<8182fd94>] (kfree_skb include/linux/skbuff.h:1271 [inline])
[<8149f130>] (sk_skb_reason_drop) from [<8182fd94>] (j1939_session_skb_drop_old net/can/j1939/transport.c:347 [inline])
[<8149f130>] (sk_skb_reason_drop) from [<8182fd94>] (j1939_xtp_rx_cts_one net/can/j1939/transport.c:1445 [inline])
[<8149f130>] (sk_skb_reason_drop) from [<8182fd94>] (j1939_xtp_rx_cts+0x220/0x3d0 net/can/j1939/transport.c:1484)
 r9:850d6d5c r8:83c7a480 r7:838dc6d8 r6:00000df2 r5:850d6d00 r4:850d6d14
[<8182fb74>] (j1939_xtp_rx_cts) from [<81830d08>] (j1939_tp_cmd_recv net/can/j1939/transport.c:2089 [inline])
[<8182fb74>] (j1939_xtp_rx_cts) from [<81830d08>] (j1939_tp_recv+0x3f4/0x530 net/can/j1939/transport.c:2161)
 r10:ddde50c8 r9:00000040 r8:838dc6d0 r7:83610000 r6:83610008 r5:83610000
 r4:83dd7540
[<81830914>] (j1939_tp_recv) from [<8182a7a0>] (j1939_can_recv+0x1e4/0x2dc net/can/j1939/main.c:108)
 r7:83610000 r6:83610008 r5:83610810 r4:83dd7540
[<8182a5bc>] (j1939_can_recv) from [<81820570>] (deliver net/can/af_can.c:572 [inline])
[<8182a5bc>] (j1939_can_recv) from [<81820570>] (can_rcv_filter+0x9c/0x218 net/can/af_can.c:606)
 r9:00000040 r8:847b06a0 r7:98c80000 r6:83dd7780 r5:00000001 r4:849ff360
[<818204d4>] (can_rcv_filter) from [<81820f14>] (can_receive+0xb4/0xf0 net/can/af_can.c:663)
 r9:00000040 r8:00000000 r7:847b0000 r6:846cc500 r5:84918d00 r4:83dd7780
[<81820e60>] (can_receive) from [<81820fd4>] (can_rcv+0x84/0xac net/can/af_can.c:687)
 r9:00000040 r8:00000002 r7:00000000 r6:00000000 r5:81820f50 r4:83dd7780
[<81820f50>] (can_rcv) from [<814c027c>] (__netif_receive_skb_one_core+0x5c/0x80 net/core/dev.c:5670)
 r5:81820f50 r4:847b0000
[<814c0220>] (__netif_receive_skb_one_core) from [<814c02e8>] (__netif_receive_skb+0x18/0x5c net/core/dev.c:5783)
 r5:ddde51b0 r4:83dd7780
[<814c02d0>] (__netif_receive_skb) from [<814c05f0>] (process_backlog+0xa0/0x17c net/core/dev.c:6115)
 r5:ddde51b0 r4:83dd7780
[<814c0550>] (process_backlog) from [<814c14fc>] (__napi_poll+0x34/0x240 net/core/dev.c:6779)
 r10:ddde50c0 r9:ddde5300 r8:df805ed0 r7:df805ecb r6:00000040 r5:ddde51b0
 r4:00000001
[<814c14c8>] (__napi_poll) from [<814c1d70>] (napi_poll net/core/dev.c:6848 [inline])
[<814c14c8>] (__napi_poll) from [<814c1d70>] (net_rx_action+0x358/0x440 net/core/dev.c:6970)
 r9:ddde5300 r8:df805ed0 r7:0000012c r6:ffffba86 r5:ddde51b0 r4:00000000
[<814c1a18>] (net_rx_action) from [<8024b51c>] (handle_softirqs+0x158/0x464 kernel/softirq.c:554)
 r10:00000008 r9:82f01800 r8:00000102 r7:04208060 r6:00000003 r5:00000004
 r4:8260408c
[<8024b3c4>] (handle_softirqs) from [<802012d0>] (__do_softirq+0x14/0x18 kernel/softirq.c:588)
 r10:84613500 r9:846135fc r8:00000030 r7:849bd300 r6:81b909e0 r5:00000002
 r4:60000113
[<802012bc>] (__do_softirq) from [<80208800>] (____do_softirq+0x10/0x14 arch/arm/kernel/irq.c:77)
[<802087f0>] (____do_softirq) from [<8196f67c>] (call_with_stack+0x1c/0x20 arch/arm/lib/call_with_stack.S:40)
[<8196f660>] (call_with_stack) from [<8020883c>] (do_softirq_own_stack+0x38/0x3c arch/arm/kernel/irq.c:82)
[<80208804>] (do_softirq_own_stack) from [<8024ba34>] (do_softirq kernel/softirq.c:455 [inline])
[<80208804>] (do_softirq_own_stack) from [<8024ba34>] (do_softirq+0x5c/0x64 kernel/softirq.c:442)
[<8024b9d8>] (do_softirq) from [<8024bb08>] (__local_bh_enable_ip+0xcc/0xd0 kernel/softirq.c:382)
 r5:00000002 r4:82f01800
[<8024ba3c>] (__local_bh_enable_ip) from [<819cba14>] (__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline])
[<8024ba3c>] (__local_bh_enable_ip) from [<819cba14>] (_raw_spin_unlock_bh+0x34/0x38 kernel/locking/spinlock.c:210)
 r5:849bd3b0 r4:83dd7840
[<819cb9e0>] (_raw_spin_unlock_bh) from [<80da3174>] (spin_unlock_bh include/linux/spinlock.h:396 [inline])
[<819cb9e0>] (_raw_spin_unlock_bh) from [<80da3174>] (nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline])
[<819cb9e0>] (_raw_spin_unlock_bh) from [<80da3174>] (nsim_dev_trap_report_work+0x29c/0x33c drivers/net/netdevsim/dev.c:851)
[<80da2ed8>] (nsim_dev_trap_report_work) from [<802660a0>] (process_one_work+0x1b4/0x4f4 kernel/workqueue.c:3229)
 r10:82c1be05 r9:82f01800 r8:02800000 r7:82c0f800 r6:82c1be00 r5:849bd300
 r4:82ea0b00
[<80265eec>] (process_one_work) from [<80266c84>] (process_scheduled_works kernel/workqueue.c:3310 [inline])
[<80265eec>] (process_one_work) from [<80266c84>] (worker_thread+0x1ec/0x3bc kernel/workqueue.c:3391)
 r10:82f01800 r9:82ea0b2c r8:61c88647 r7:82c0f820 r6:82604d40 r5:82c0f800
 r4:82ea0b00
[<80266a98>] (worker_thread) from [<8026fd00>] (kthread+0x104/0x134 kernel/kthread.c:389)
 r10:00000000 r9:df889e78 r8:82eb5dc0 r7:82ea0b00 r6:80266a98 r5:82f01800
 r4:82eb5c80
[<8026fbfc>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xdf985fb0 to 0xdf985ff8)
5fa0:                                     00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8026fbfc r4:82eb5c80
Rebooting in 86400 seconds..