vxcan1: j1939_tp_rxtimer: 0xffff888026f4bc00: rx timeout, send abort vxcan1: j1939_xtp_rx_abort_one: 0xffff888026f4bc00: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. ====================================================== WARNING: possible circular locking dependency detected 6.1.66-syzkaller #0 Not tainted ------------------------------------------------------ ksoftirqd/1/21 is trying to acquire lock: ffff888021335088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff888021335088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff888021335088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_activate+0x4d/0x3d0 net/can/j1939/transport.c:1564 but task is already holding lock: ffff8880770015c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff8880770015c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x54/0x3e0 net/can/j1939/socket.c:207 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&jsk->sk_session_queue_lock){+.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_sk_queue_drop_all+0x3a/0x240 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0xe9/0x150 net/can/j1939/socket.c:1280 j1939_netdev_notify+0x209/0x2e0 net/can/j1939/main.c:381 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455 __dev_notify_flags+0x304/0x610 dev_change_flags+0xe7/0x190 net/core/dev.c:8655 do_setlink+0xf5d/0x3e60 net/core/rtnetlink.c:2808 __rtnl_newlink net/core/rtnetlink.c:3576 [inline] rtnl_newlink+0x172c/0x2050 net/core/rtnetlink.c:3623 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6122 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2499 ___sys_sendmsg net/socket.c:2553 [inline] __sys_sendmsg+0x2a9/0x390 net/socket.c:2582 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&priv->j1939_socks_lock){+.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_sk_errqueue+0x92/0x140 net/can/j1939/socket.c:1081 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put+0x100/0x460 net/can/j1939/transport.c:299 j1939_session_deactivate_locked net/can/j1939/transport.c:1086 [inline] j1939_cancel_active_session+0x350/0x480 net/can/j1939/transport.c:2194 j1939_netdev_notify+0x201/0x2e0 net/can/j1939/main.c:380 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455 __dev_notify_flags+0x304/0x610 dev_change_flags+0xe7/0x190 net/core/dev.c:8655 do_setlink+0xf5d/0x3e60 net/core/rtnetlink.c:2808 __rtnl_newlink net/core/rtnetlink.c:3576 [inline] rtnl_newlink+0x172c/0x2050 net/core/rtnetlink.c:3623 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6122 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2499 ___sys_sendmsg net/socket.c:2553 [inline] __sys_sendmsg+0x2a9/0x390 net/socket.c:2582 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&priv->active_session_list_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 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+0x4d/0x3d0 net/can/j1939/transport.c:1564 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x268/0x3e0 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1108 [inline] j1939_xtp_rx_abort_one+0x359/0x410 net/can/j1939/transport.c:1351 j1939_xtp_rx_abort net/can/j1939/transport.c:1362 [inline] j1939_tp_cmd_recv net/can/j1939/transport.c:2111 [inline] j1939_tp_recv+0x956/0x1000 net/can/j1939/transport.c:2144 j1939_can_recv+0x72e/0xb10 net/can/j1939/main.c:112 deliver net/can/af_can.c:573 [inline] can_rcv_filter+0x349/0x7c0 net/can/af_can.c:607 can_receive+0x319/0x470 net/can/af_can.c:664 can_rcv+0x140/0x260 net/can/af_can.c:688 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5639 process_backlog+0x381/0x760 net/core/dev.c:5967 __napi_poll+0xc7/0x470 net/core/dev.c:6534 napi_poll net/core/dev.c:6601 [inline] net_rx_action+0x70f/0xeb0 net/core/dev.c:6712 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 run_ksoftirqd+0xc1/0x120 kernel/softirq.c:934 smpboot_thread_fn+0x52c/0xa30 kernel/smpboot.c:164 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 other info that might help us debug this: Chain exists of: &priv->active_session_list_lock --> &priv->j1939_socks_lock --> &jsk->sk_session_queue_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&jsk->sk_session_queue_lock); lock(&priv->j1939_socks_lock); lock(&jsk->sk_session_queue_lock); lock(&priv->active_session_list_lock); *** DEADLOCK *** 3 locks held by ksoftirqd/1/21: #0: ffffffff8d12a1e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline] #0: ffffffff8d12a1e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8d12a1e0 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x2c9/0x760 net/core/dev.c:5966 #1: ffffffff8d12a1e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline] #1: ffffffff8d12a1e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #1: ffffffff8d12a1e0 (rcu_read_lock){....}-{1:2}, at: can_receive+0x1c4/0x470 net/can/af_can.c:657 #2: ffff8880770015c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #2: ffff8880770015c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x54/0x3e0 net/can/j1939/socket.c:207 stack backtrace: CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 6.1.66-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 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+0x4d/0x3d0 net/can/j1939/transport.c:1564 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x268/0x3e0 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1108 [inline] j1939_xtp_rx_abort_one+0x359/0x410 net/can/j1939/transport.c:1351 j1939_xtp_rx_abort net/can/j1939/transport.c:1362 [inline] j1939_tp_cmd_recv net/can/j1939/transport.c:2111 [inline] j1939_tp_recv+0x956/0x1000 net/can/j1939/transport.c:2144 j1939_can_recv+0x72e/0xb10 net/can/j1939/main.c:112 deliver net/can/af_can.c:573 [inline] can_rcv_filter+0x349/0x7c0 net/can/af_can.c:607 can_receive+0x319/0x470 net/can/af_can.c:664 can_rcv+0x140/0x260 net/can/af_can.c:688 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5639 process_backlog+0x381/0x760 net/core/dev.c:5967 __napi_poll+0xc7/0x470 net/core/dev.c:6534 napi_poll net/core/dev.c:6601 [inline] net_rx_action+0x70f/0xeb0 net/core/dev.c:6712 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 run_ksoftirqd+0xc1/0x120 kernel/softirq.c:934 smpboot_thread_fn+0x52c/0xa30 kernel/smpboot.c:164 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306