vcan0: j1939_tp_rxtimer: 0xffff888082cc0000: rx timeout, send abort ====================================================== WARNING: possible circular locking dependency detected 6.1.0-syzkaller-13872-gb6bb9676f216 #0 Not tainted ------------------------------------------------------ ksoftirqd/1/20 is trying to acquire lock: ffff88807e89d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88807e89d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 but task is already holding lock: ffff88807e89d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88807e89d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff88807e89d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe9/0x220 net/can/j1939/transport.c:1248 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&priv->active_session_list_lock){+.-.}-{2:2}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_session_list_lock net/can/j1939/transport.c:238 [inline] j1939_session_activate+0x47/0x4b0 net/can/j1939/transport.c:1561 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x1b6/0x450 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1109 [inline] j1939_session_completed+0x19a/0x1f0 net/can/j1939/transport.c:1222 j1939_xtp_rx_dat_one+0x591/0xee0 net/can/j1939/transport.c:1899 j1939_xtp_rx_dat net/can/j1939/transport.c:1937 [inline] j1939_tp_recv+0x7cf/0xcd0 net/can/j1939/transport.c:2131 j1939_can_recv net/can/j1939/main.c:112 [inline] j1939_can_recv+0x78e/0xa30 net/can/j1939/main.c:38 deliver net/can/af_can.c:572 [inline] can_rcv_filter+0x5d4/0x8d0 net/can/af_can.c:606 can_receive+0x31d/0x580 net/can/af_can.c:663 can_rcv+0x1e1/0x230 net/can/af_can.c:687 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5482 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5596 process_backlog+0x3e4/0x810 net/core/dev.c:5924 __napi_poll+0xb8/0x770 net/core/dev.c:6485 napi_poll net/core/dev.c:6552 [inline] net_rx_action+0xa00/0xde0 net/core/dev.c:6663 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x659/0xa20 kernel/smpboot.c:164 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 -> #1 (&jsk->sk_session_queue_lock){+.-.}-{2:2}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_sk_queue_drop_all+0x3b/0x2f0 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0x7f/0x160 net/can/j1939/socket.c:1275 j1939_netdev_notify+0x19d/0x1d0 net/can/j1939/main.c:379 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1944 call_netdevice_notifiers_extack net/core/dev.c:1982 [inline] call_netdevice_notifiers net/core/dev.c:1996 [inline] __dev_notify_flags+0x1ea/0x2d0 net/core/dev.c:8571 dev_change_flags+0x11b/0x170 net/core/dev.c:8607 do_setlink+0x9f1/0x3bb0 net/core/rtnetlink.c:2827 __rtnl_newlink+0xd69/0x1840 net/core/rtnetlink.c:3590 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1932 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2559 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&priv->j1939_socks_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 __j1939_session_cancel+0x3b9/0x460 net/can/j1939/transport.c:1132 j1939_tp_rxtimer.cold+0x1f6/0x24f net/can/j1939/transport.c:1257 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x690/0xfb0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x659/0xa20 kernel/smpboot.c:164 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 other info that might help us debug this: Chain exists of: &priv->j1939_socks_lock --> &jsk->sk_session_queue_lock --> &priv->active_session_list_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&priv->active_session_list_lock); lock(&jsk->sk_session_queue_lock); lock(&priv->active_session_list_lock); lock(&priv->j1939_socks_lock); *** DEADLOCK *** 1 lock held by ksoftirqd/1/20: #0: ffff88807e89d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #0: ffff88807e89d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] #0: ffff88807e89d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe9/0x220 net/can/j1939/transport.c:1248 stack backtrace: CPU: 1 PID: 20 Comm: ksoftirqd/1 Not tainted 6.1.0-syzkaller-13872-gb6bb9676f216 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 __j1939_session_cancel+0x3b9/0x460 net/can/j1939/transport.c:1132 j1939_tp_rxtimer.cold+0x1f6/0x24f net/can/j1939/transport.c:1257 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x690/0xfb0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x659/0xa20 kernel/smpboot.c:164 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 vcan0: j1939_tp_rxtimer: 0xffff888082cc0000: abort rx timeout. Force session deactivation vcan0: j1939_tp_rxtimer: 0xffff88803351d800: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff88801e06ec00: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_xtp_rx_abort_one: 0xffff888087aed400: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_tp_rxtimer: 0xffff88803351d800: abort rx timeout. Force session deactivation