vcan0: j1939_xtp_rx_abort_one: 0xffff88801f249400: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_xtp_rx_abort_one: 0xffff88801f24a800: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. ====================================================== WARNING: possible circular locking dependency detected 5.17.0-rc6-syzkaller-00184-g38f80f42147f #0 Not tainted ------------------------------------------------------ ksoftirqd/1/19 is trying to acquire lock: ffff888047929088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] ffff888047929088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff888047929088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_activate+0x43/0x4b0 net/can/j1939/transport.c:1553 but task is already holding lock: ffff88802baaa5c0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] ffff88802baaa5c0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x56/0x460 net/can/j1939/socket.c:204 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&jsk->sk_session_queue_lock){+.-.}-{2:2}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:354 [inline] j1939_sk_queue_drop_all+0x40/0x2f0 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0x7b/0x160 net/can/j1939/socket.c:1272 j1939_netdev_notify+0x199/0x1d0 net/can/j1939/main.c:372 notifier_call_chain+0xb5/0x200 kernel/notifier.c:84 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1919 call_netdevice_notifiers_extack net/core/dev.c:1931 [inline] call_netdevice_notifiers net/core/dev.c:1945 [inline] __dev_notify_flags+0x1da/0x2b0 net/core/dev.c:8179 dev_change_flags+0x112/0x170 net/core/dev.c:8215 do_setlink+0x96d/0x3a10 net/core/rtnetlink.c:2731 __rtnl_newlink+0xdf5/0x1760 net/core/rtnetlink.c:3416 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3531 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5596 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2413 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #1 (&priv->j1939_socks_lock){+.-.}-{2:2}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:354 [inline] j1939_sk_errqueue+0x9f/0x1a0 net/can/j1939/socket.c:1078 __j1939_session_cancel+0x3b9/0x460 net/can/j1939/transport.c:1124 j1939_tp_rxtimer.cold+0x1f6/0x24f net/can/j1939/transport.c:1249 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 -> #0 (&priv->active_session_list_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3063 [inline] check_prevs_add kernel/locking/lockdep.c:3186 [inline] validate_chain kernel/locking/lockdep.c:3801 [inline] __lock_acquire+0x2ad4/0x56c0 kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:354 [inline] j1939_session_list_lock net/can/j1939/transport.c:238 [inline] j1939_session_activate+0x43/0x4b0 net/can/j1939/transport.c:1553 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x29b/0x460 net/can/j1939/socket.c:205 j1939_session_deactivate_activate_next+0xc8/0xd3 net/can/j1939/transport.c:1101 j1939_xtp_rx_abort_one.cold+0x20b/0x33c net/can/j1939/transport.c:1340 j1939_xtp_rx_abort net/can/j1939/transport.c:1352 [inline] j1939_tp_cmd_recv net/can/j1939/transport.c:2100 [inline] j1939_tp_recv+0xb3d/0xcb0 net/can/j1939/transport.c:2133 j1939_can_recv+0x6ff/0x9a0 net/can/j1939/main.c:108 deliver net/can/af_can.c:574 [inline] can_rcv_filter+0x5d4/0x8d0 net/can/af_can.c:608 can_receive+0x31d/0x580 net/can/af_can.c:665 can_rcv+0x120/0x1c0 net/can/af_can.c:696 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5351 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5465 process_backlog+0x2a5/0x6c0 net/core/dev.c:5797 __napi_poll+0xb3/0x6e0 net/core/dev.c:6365 napi_poll net/core/dev.c:6432 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:6519 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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/1/19: #0: ffffffff8bb845e0 (rcu_read_lock){....}-{1:2}, at: __skb_unlink include/linux/skbuff.h:2168 [inline] #0: ffffffff8bb845e0 (rcu_read_lock){....}-{1:2}, at: __skb_dequeue include/linux/skbuff.h:2183 [inline] #0: ffffffff8bb845e0 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x250/0x6c0 net/core/dev.c:5795 #1: ffffffff8bb845e0 (rcu_read_lock){....}-{1:2}, at: can_receive+0x1ef/0x580 net/can/af_can.c:655 #2: ffff88802baaa5c0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] #2: ffff88802baaa5c0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x56/0x460 net/can/j1939/socket.c:204 stack backtrace: CPU: 1 PID: 19 Comm: ksoftirqd/1 Not tainted 5.17.0-rc6-syzkaller-00184-g38f80f42147f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2143 check_prev_add kernel/locking/lockdep.c:3063 [inline] check_prevs_add kernel/locking/lockdep.c:3186 [inline] validate_chain kernel/locking/lockdep.c:3801 [inline] __lock_acquire+0x2ad4/0x56c0 kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:354 [inline] j1939_session_list_lock net/can/j1939/transport.c:238 [inline] j1939_session_activate+0x43/0x4b0 net/can/j1939/transport.c:1553 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x29b/0x460 net/can/j1939/socket.c:205 j1939_session_deactivate_activate_next+0xc8/0xd3 net/can/j1939/transport.c:1101 j1939_xtp_rx_abort_one.cold+0x20b/0x33c net/can/j1939/transport.c:1340 j1939_xtp_rx_abort net/can/j1939/transport.c:1352 [inline] j1939_tp_cmd_recv net/can/j1939/transport.c:2100 [inline] j1939_tp_recv+0xb3d/0xcb0 net/can/j1939/transport.c:2133 j1939_can_recv+0x6ff/0x9a0 net/can/j1939/main.c:108 deliver net/can/af_can.c:574 [inline] can_rcv_filter+0x5d4/0x8d0 net/can/af_can.c:608 can_receive+0x31d/0x580 net/can/af_can.c:665 can_rcv+0x120/0x1c0 net/can/af_can.c:696 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5351 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5465 process_backlog+0x2a5/0x6c0 net/core/dev.c:5797 __napi_poll+0xb3/0x6e0 net/core/dev.c:6365 napi_poll net/core/dev.c:6432 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:6519 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 vcan0: j1939_tp_rxtimer: 0xffff8880730c6800: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff888069a3fc00: 0x00000: (3) A timeout occurred and this is the connection abort to close the session.