vcan0: j1939_tp_rxtimer: 0xffff88804957e400: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff88804957e400: 0x40000: (3) A timeout occurred and this is the connection abort to close the session. ====================================================== WARNING: possible circular locking dependency detected 5.19.0-rc7-syzkaller-00192-gb5177ed92bf6 #0 Not tainted ------------------------------------------------------ ksoftirqd/0/15 is trying to acquire lock: ffff88805a29d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] ffff88805a29d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff88805a29d088 (&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: ffff88807a53d5b8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] ffff88807a53d5b8 (&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:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 call_netdevice_notifiers_extack net/core/dev.c:1983 [inline] call_netdevice_notifiers net/core/dev.c:1997 [inline] __dev_notify_flags+0x1da/0x2b0 net/core/dev.c:8577 dev_change_flags+0x112/0x170 net/core/dev.c:8613 do_setlink+0x961/0x3bb0 net/core/rtnetlink.c:2780 __rtnl_newlink+0xd6a/0x17e0 net/core/rtnetlink.c:3546 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3593 rtnetlink_rcv_msg+0x43a/0xc90 net/core/rtnetlink.c:6089 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 ____sys_sendmsg+0x6eb/0x810 net/socket.c:2488 ___sys_sendmsg+0xf3/0x170 net/socket.c:2542 __sys_sendmsg net/socket.c:2571 [inline] __do_sys_sendmsg net/socket.c:2580 [inline] __se_sys_sendmsg net/socket.c:2578 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2578 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+0x63/0xcd -> #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:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 lock_is_held_type+0xff/0x140 kernel/locking/lockdep.c:5713 lock_is_held include/linux/lockdep.h:279 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x480/0x570 kernel/locking/lockdep.c:5636 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747 __unix_dgram_recvmsg+0x226/0xb90 net/unix/af_unix.c:2387 unix_dgram_recvmsg+0xc0/0xe0 net/unix/af_unix.c:2487 sock_recvmsg_nosec net/socket.c:995 [inline] ____sys_recvmsg+0x536/0x600 net/socket.c:2705 ___sys_recvmsg+0x127/0x200 net/socket.c:2749 do_recvmmsg+0x254/0x6d0 net/socket.c:2843 __sys_recvmmsg net/socket.c:2922 [inline] __do_sys_recvmmsg net/socket.c:2945 [inline] __se_sys_recvmmsg net/socket.c:2938 [inline] __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2938 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+0x63/0xcd -> #0 (&priv->active_session_list_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x2abe/0x5660 kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5630 __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:1351 [inline] j1939_tp_cmd_recv net/can/j1939/transport.c:2100 [inline] j1939_tp_recv+0xb28/0xcb0 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:5484 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5598 process_backlog+0x3a0/0x7c0 net/core/dev.c:5926 __napi_poll+0xb3/0x6e0 net/core/dev.c:6492 napi_poll net/core/dev.c:6559 [inline] net_rx_action+0x9c1/0xd90 net/core/dev.c:6670 __do_softirq+0x29b/0x9c2 kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 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/0/15: #0: ffffffff8bd87120 (rcu_read_lock){....}-{1:2}, at: __skb_unlink include/linux/skbuff.h:2469 [inline] #0: ffffffff8bd87120 (rcu_read_lock){....}-{1:2}, at: __skb_dequeue include/linux/skbuff.h:2484 [inline] #0: ffffffff8bd87120 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x34b/0x7c0 net/core/dev.c:5924 #1: ffffffff8bd87120 (rcu_read_lock){....}-{1:2}, at: can_receive+0x1ef/0x580 net/can/af_can.c:655 #2: ffff88807a53d5b8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] #2: ffff88807a53d5b8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x56/0x460 net/can/j1939/socket.c:204 stack backtrace: CPU: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 5.19.0-rc7-syzkaller-00192-gb5177ed92bf6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 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:2175 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x2abe/0x5660 kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5630 __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:1351 [inline] j1939_tp_cmd_recv net/can/j1939/transport.c:2100 [inline] j1939_tp_recv+0xb28/0xcb0 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:5484 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5598 process_backlog+0x3a0/0x7c0 net/core/dev.c:5926 __napi_poll+0xb3/0x6e0 net/core/dev.c:6492 napi_poll net/core/dev.c:6559 [inline] net_rx_action+0x9c1/0xd90 net/core/dev.c:6670 __do_softirq+0x29b/0x9c2 kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 vcan0: j1939_xtp_rx_abort_one: 0xffff88804957c000: 0x40000: (3) A timeout occurred and this is the connection abort to close the session.