------------[ cut here ]------------
WARNING: CPU: 0 PID: 15 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: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 6.11.0-syzkaller #0
Hardware name: ARM-Versatile Express
Call trace: frame pointer underflow
[<81966cb8>] (dump_backtrace) from [<81966db4>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:00000000 r6:826228c4 r5:00000000 r4:8200e404
[<81966d9c>] (show_stack) from [<81984a58>] (__dump_stack lib/dump_stack.c:93 [inline])
[<81966d9c>] (show_stack) from [<81984a58>] (dump_stack_lvl+0x54/0x7c lib/dump_stack.c:119)
[<81984a04>] (dump_stack_lvl) from [<81984a98>] (dump_stack+0x18/0x1c lib/dump_stack.c:128)
 r5:00000000 r4:8286ed18
[<81984a80>] (dump_stack) from [<8196785c>] (panic+0x120/0x368 kernel/panic.c:354)
[<8196773c>] (panic) from [<802421d4>] (check_panic_on_warn kernel/panic.c:243 [inline])
[<8196773c>] (panic) from [<802421d4>] (get_taint+0x0/0x1c kernel/panic.c:238)
 r3:8260c5c4 r2:00000001 r1:81ff6c38 r0:81ffea04
 r7:8081a110
[<80242160>] (check_panic_on_warn) from [<80242328>] (__warn+0x7c/0x180 kernel/panic.c:741)
[<802422ac>] (__warn) from [<80242614>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:774)
 r8:00000009 r7:8205cdc4 r6:df801c64 r5:82e3b000 r4:00000000
[<80242430>] (warn_slowpath_fmt) from [<8081a110>] (refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28)
 r10:20000113 r9:8525d65c r8:83e9f600 r7:00000000 r6:817f7394 r5:00000002
 r4:83e9f600
[<80819fd4>] (refcount_warn_saturate) from [<8146782c>] (__refcount_sub_and_test include/linux/refcount.h:275 [inline])
[<80819fd4>] (refcount_warn_saturate) from [<8146782c>] (__refcount_dec_and_test include/linux/refcount.h:307 [inline])
[<80819fd4>] (refcount_warn_saturate) from [<8146782c>] (refcount_dec_and_test include/linux/refcount.h:325 [inline])
[<80819fd4>] (refcount_warn_saturate) from [<8146782c>] (skb_unref include/linux/skbuff.h:1232 [inline])
[<80819fd4>] (refcount_warn_saturate) from [<8146782c>] (__sk_skb_reason_drop net/core/skbuff.c:1213 [inline])
[<80819fd4>] (refcount_warn_saturate) from [<8146782c>] (sk_skb_reason_drop+0x1d8/0x248 net/core/skbuff.c:1241)
[<81467654>] (sk_skb_reason_drop) from [<817f7394>] (kfree_skb_reason include/linux/skbuff.h:1262 [inline])
[<81467654>] (sk_skb_reason_drop) from [<817f7394>] (kfree_skb include/linux/skbuff.h:1271 [inline])
[<81467654>] (sk_skb_reason_drop) from [<817f7394>] (j1939_session_skb_drop_old net/can/j1939/transport.c:347 [inline])
[<81467654>] (sk_skb_reason_drop) from [<817f7394>] (j1939_xtp_rx_cts_one net/can/j1939/transport.c:1445 [inline])
[<81467654>] (sk_skb_reason_drop) from [<817f7394>] (j1939_xtp_rx_cts+0x220/0x3d0 net/can/j1939/transport.c:1484)
 r9:8525d65c r8:83e9f600 r7:83f64918 r6:00000df2 r5:8525d600 r4:8525d614
[<817f7174>] (j1939_xtp_rx_cts) from [<817f8308>] (j1939_tp_cmd_recv net/can/j1939/transport.c:2089 [inline])
[<817f7174>] (j1939_xtp_rx_cts) from [<817f8308>] (j1939_tp_recv+0x3f4/0x530 net/can/j1939/transport.c:2161)
 r10:dddd0ec8 r9:00000040 r8:83f64910 r7:84642000 r6:84642008 r5:84642000
 r4:8419a540
[<817f7f14>] (j1939_tp_recv) from [<817f1da0>] (j1939_can_recv+0x1e4/0x2dc net/can/j1939/main.c:108)
 r7:84642000 r6:84642008 r5:84642810 r4:8419a540
[<817f1bbc>] (j1939_can_recv) from [<817e7b6c>] (deliver net/can/af_can.c:572 [inline])
[<817f1bbc>] (j1939_can_recv) from [<817e7b6c>] (can_rcv_filter+0x9c/0x218 net/can/af_can.c:606)
 r9:00000040 r8:84b4c6a0 r7:98c80000 r6:8419a780 r5:00000001 r4:850e43f0
[<817e7ad0>] (can_rcv_filter) from [<817e8510>] (can_receive+0xb4/0xf0 net/can/af_can.c:663)
 r9:00000040 r8:00000000 r7:84b4c000 r6:846a4a80 r5:84718000 r4:8419a780
[<817e845c>] (can_receive) from [<817e85d0>] (can_rcv+0x84/0xac net/can/af_can.c:687)
 r9:00000040 r8:00000002 r7:00000000 r6:00000000 r5:817e854c r4:8419a780
[<817e854c>] (can_rcv) from [<814886a4>] (__netif_receive_skb_one_core+0x5c/0x80 net/core/dev.c:5662)
 r5:817e854c r4:84b4c000
[<81488648>] (__netif_receive_skb_one_core) from [<81488710>] (__netif_receive_skb+0x18/0x5c net/core/dev.c:5775)
 r5:dddd0fb0 r4:8419a780
[<814886f8>] (__netif_receive_skb) from [<81488a00>] (process_backlog+0x88/0x15c net/core/dev.c:6107)
 r5:dddd0fb0 r4:8419a780
[<81488978>] (process_backlog) from [<81489904>] (__napi_poll+0x34/0x240 net/core/dev.c:6771)
 r10:dddd0ec0 r9:dddd1100 r8:df801ea0 r7:df801e9b r6:00000040 r5:dddd0fb0
 r4:00000001
[<814898d0>] (__napi_poll) from [<8148a13c>] (napi_poll net/core/dev.c:6840 [inline])
[<814898d0>] (__napi_poll) from [<8148a13c>] (net_rx_action+0x338/0x420 net/core/dev.c:6962)
 r9:dddd1100 r8:df801ea0 r7:0000012c r6:000007b8 r5:dddd0fb0 r4:00000000
[<81489e04>] (net_rx_action) from [<8024b5d8>] (handle_softirqs+0x15c/0x468 kernel/softirq.c:554)
 r10:00000008 r9:82e3b000 r8:00000100 r7:04208040 r6:00000003 r5:00000004
 r4:8260408c
[<8024b47c>] (handle_softirqs) from [<8024b9d4>] (__do_softirq kernel/softirq.c:588 [inline])
[<8024b47c>] (handle_softirqs) from [<8024b9d4>] (invoke_softirq kernel/softirq.c:428 [inline])
[<8024b47c>] (handle_softirqs) from [<8024b9d4>] (__irq_exit_rcu+0xa4/0x164 kernel/softirq.c:637)
 r10:00000000 r9:82e3b000 r8:00000000 r7:df855ef8 r6:821af29c r5:821ef71c
 r4:82e3b000
[<8024b930>] (__irq_exit_rcu) from [<8024bcd4>] (irq_exit+0x10/0x18 kernel/softirq.c:661)
 r5:821ef71c r4:824b8b5c
[<8024bcc4>] (irq_exit) from [<81985354>] (generic_handle_arch_irq+0x7c/0x80 kernel/irq/handle.c:240)
[<819852d8>] (generic_handle_arch_irq) from [<81936768>] (call_with_stack+0x1c/0x20 arch/arm/lib/call_with_stack.S:40)
 r9:82e3b000 r8:826240c8 r7:df855f2c r6:ffffffff r5:60000013 r4:8024b92c
[<8193674c>] (call_with_stack) from [<80200bcc>] (__irq_svc+0x8c/0xbc arch/arm/kernel/entry-armv.S:227)
Exception stack(0xdf855ef8 to 0xdf855f40)
5ee0:                                                       82e3b000 00000100
5f00: 003af880 04208040 00000000 82e3b000 82cb6100 00000001 826240c8 00000002
5f20: 00000000 df855f54 5b917000 df855f48 00000000 8024b92c 60000013 ffffffff
[<8024b8e4>] (run_ksoftirqd) from [<80274f1c>] (smpboot_thread_fn+0x16c/0x288 kernel/smpboot.c:164)
[<80274db0>] (smpboot_thread_fn) from [<8026faf4>] (kthread+0x104/0x134 kernel/kthread.c:389)
 r10:00000000 r9:df819de8 r8:82cb6240 r7:82cb6100 r6:80274db0 r5:82e3b000
 r4:82cb6140 r3:00000000
[<8026f9f0>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xdf855fb0 to 0xdf855ff8)
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 r5:8026f9f0 r4:82cb6140
Rebooting in 86400 seconds..