vxcan1: j1939_tp_rxtimer: 0xffff88805b01b000: rx timeout, send abort vxcan1: j1939_xtp_rx_abort_one: 0xffff88805b01b000: 0x00100: (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+0x14a/0x210 lib/refcount.c:28 Modules linked in: CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.13.0-rc1-syzkaller-00036-g5076001689e4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28 Code: ff 89 de e8 98 23 f9 fc 84 db 0f 85 66 ff ff ff e8 ab 21 f9 fc c6 05 77 cf a6 0b 01 90 48 c7 c7 a0 61 d1 8b e8 47 6b b9 fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 88 21 f9 fc 0f b6 1d 52 cf a6 0b 31 RSP: 0018:ffffc900001577c8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff815a5159 RDX: ffff88801d2d0000 RSI: ffffffff815a5166 RDI: 0000000000000001 RBP: ffff88805b73fea4 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000002 R13: 0000000000000000 R14: ffff88805b73fea4 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff6eb81afb8 CR3: 000000002a6b6000 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:1233 [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:1263 [inline] kfree_skb include/linux/skbuff.h:1272 [inline] j1939_session_destroy+0x163/0x460 net/can/j1939/transport.c:282 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put net/can/j1939/transport.c:299 [inline] j1939_xtp_rx_abort_one+0x3f9/0x560 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+0xcf8/0xf50 net/can/j1939/transport.c:2161 j1939_can_recv+0x78f/0xa50 net/can/j1939/main.c:108 deliver net/can/af_can.c:573 [inline] can_rcv_filter+0x2a8/0x900 net/can/af_can.c:607 can_receive+0x320/0x5c0 net/can/af_can.c:664 can_rcv+0x1e2/0x280 net/can/af_can.c:688 __netif_receive_skb_one_core+0x1b1/0x1e0 net/core/dev.c:5672 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5785 process_backlog+0x443/0x15f0 net/core/dev.c:6117 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6877 napi_poll net/core/dev.c:6946 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7068 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554 run_ksoftirqd kernel/softirq.c:943 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:935 smpboot_thread_fn+0x661/0xa30 kernel/smpboot.c:164 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