------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 7540 at lib/refcount.c:28 refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28
Modules linked in:
CPU: 1 UID: 0 PID: 7540 Comm: modprobe Not tainted 6.12.0-rc1-syzkaller-g80cb3fb61135 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28
lr : refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28
sp : ffff800080017660
x29: ffff800080017660 x28: 0000000000000001 x27: 00000000ffffffff
x26: 1fffe00018da3f18 x25: dfff800000000000 x24: 0000000000000000
x23: ffff0000df952ea4 x22: ffff80008a57ce90 x21: 0000000000000003
x20: ffff0000df952ea4 x19: ffff800092a80000 x18: 0000000000000008
x17: 0000000000000000 x16: ffff8000830b4c50 x15: 0000000000000001
x14: 1fffe000366cc0e2 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000102 x10: 0000000000ff0100 x9 : 237489df7c1fbb00
x8 : 237489df7c1fbb00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800080016d98 x4 : ffff80008f8dcac0 x3 : ffff800080626e34
x2 : 0000000000000001 x1 : 0000000100000100 x0 : 0000000000000000
Call trace:
 refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28
 __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+0x210/0x43c net/core/skbuff.c:1241
 kfree_skb_reason include/linux/skbuff.h:1262 [inline]
 kfree_skb include/linux/skbuff.h:1271 [inline]
 j1939_session_destroy net/can/j1939/transport.c:282 [inline]
 __j1939_session_release net/can/j1939/transport.c:294 [inline]
 kref_put include/linux/kref.h:65 [inline]
 j1939_session_put+0x1c8/0x460 net/can/j1939/transport.c:299
 j1939_xtp_rx_dat_one+0x680/0xdb4
 j1939_xtp_rx_dat net/can/j1939/transport.c:1957 [inline]
 j1939_tp_recv+0x2c8/0xe14 net/can/j1939/transport.c:2151
 j1939_can_recv+0x5bc/0x934 net/can/j1939/main.c:108
 deliver net/can/af_can.c:572 [inline]
 can_rcv_filter+0x308/0x714 net/can/af_can.c:606
 can_receive+0x328/0x488 net/can/af_can.c:663
 can_rcv+0x128/0x240 net/can/af_can.c:687
 __netif_receive_skb_one_core net/core/dev.c:5662 [inline]
 __netif_receive_skb+0x18c/0x3c8 net/core/dev.c:5775
 process_backlog+0x640/0x123c net/core/dev.c:6107
 __napi_poll+0xb4/0x3fc net/core/dev.c:6771
 napi_poll net/core/dev.c:6840 [inline]
 net_rx_action+0x6a8/0xf4c net/core/dev.c:6962
 handle_softirqs+0x2e0/0xbf8 kernel/softirq.c:554
 __do_softirq+0x14/0x20 kernel/softirq.c:588
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81
 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:889
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:86
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0x1d8/0x434 kernel/softirq.c:637
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:649
 __el1_irq arch/arm64/kernel/entry-common.c:549 [inline]
 el1_interrupt+0x38/0x68 arch/arm64/kernel/entry-common.c:563
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:568
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:594
 invoke_syscall+0x90/0x2b8 arch/arm64/kernel/syscall.c:48
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:732
 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:750
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598
irq event stamp: 2741
hardirqs last  enabled at (2740): [<ffff80008039c81c>] __up_console_sem kernel/printk/printk.c:344 [inline]
hardirqs last  enabled at (2740): [<ffff80008039c81c>] __console_unlock+0x70/0xc4 kernel/printk/printk.c:2844
hardirqs last disabled at (2741): [<ffff80008b481ff4>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:479
softirqs last  enabled at (1346): [<ffff8000800307f8>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (2655): [<ffff800080020db4>] __do_softirq+0x14/0x20 kernel/softirq.c:588
---[ end trace 0000000000000000 ]---