vxcan1: j1939_xtp_rx_abort_one: 0x000000001898b195: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 16 at lib/refcount.c:28 refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28 Modules linked in: CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-syzkaller-g7b1d1d4cfac0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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 : ffff8000979f7470 x29: ffff8000979f7470 x28: 0000000000000001 x27: 00000000ffffffff x26: 1fffe00018d09c18 x25: dfff800000000000 x24: 0000000000000000 x23: ffff0000d08cd5e4 x22: ffff80008a63b670 x21: 0000000000000003 x20: ffff0000d08cd5e4 x19: ffff800092b74000 x18: 0000000000000008 x17: 0000000000000000 x16: ffff80008b47f65c x15: ffff700011f29534 x14: 1ffff00011f29534 x13: 0000000000000004 x12: ffffffffffffffff x11: 0000000000000102 x10: 0000000000ff0100 x9 : 60080877a14a6700 x8 : 60080877a14a6700 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff8000979f6b98 x4 : ffff80008f9bd220 x3 : ffff8000803921b4 x2 : 0000000000000000 x1 : 0000000100000100 x0 : 0000000000000000 Call trace: refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28 (P) refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28 (L) __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_abort_one+0xd4/0x358 net/can/j1939/transport.c:1354 j1939_xtp_rx_abort net/can/j1939/transport.c:1362 [inline] j1939_tp_cmd_recv net/can/j1939/transport.c:2128 [inline] j1939_tp_recv+0x814/0xe14 net/can/j1939/transport.c:2161 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:5670 [inline] __netif_receive_skb+0x18c/0x3c8 net/core/dev.c:5783 process_backlog+0x640/0x123c net/core/dev.c:6115 __napi_poll+0xb4/0x3fc net/core/dev.c:6779 napi_poll net/core/dev.c:6848 [inline] net_rx_action+0x6a8/0xf4c net/core/dev.c:6970 handle_softirqs+0x2e0/0xbf8 kernel/softirq.c:554 run_ksoftirqd+0x70/0xc0 kernel/softirq.c:949 smpboot_thread_fn+0x4b0/0x90c kernel/smpboot.c:164 kthread+0x288/0x310 kernel/kthread.c:389 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 irq event stamp: 1127127 hardirqs last enabled at (1127126): [] __up_console_sem kernel/printk/printk.c:344 [inline] hardirqs last enabled at (1127126): [] __console_unlock+0x70/0xc4 kernel/printk/printk.c:2844 hardirqs last disabled at (1127127): [] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:488 softirqs last enabled at (1127054): [] softirq_handle_end kernel/softirq.c:400 [inline] softirqs last enabled at (1127054): [] handle_softirqs+0xa38/0xbf8 kernel/softirq.c:582 softirqs last disabled at (1127059): [] run_ksoftirqd+0x70/0xc0 kernel/softirq.c:949 ---[ end trace 0000000000000000 ]--- vkms_vblank_simulate: vblank timer overrun vxcan1: j1939_tp_rxtimer: 0x00000000680c0aaa: rx timeout, send abort vxcan1: j1939_xtp_rx_abort_one: 0x00000000680c0aaa: 0x00000: (3) A timeout occurred and this is the connection abort to close the session.