======================================================
WARNING: possible circular locking dependency detected
6.2.0-rc2-syzkaller-00301-g6bd4755c7c49 #0 Not tainted
------------------------------------------------------
udevd/4433 is trying to acquire lock:
ffff8880563f5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline]
ffff8880563f5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline]
ffff8880563f5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_activate+0x47/0x4b0 net/can/j1939/transport.c:1561

but task is already holding lock:
ffff8880181f15c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline]
ffff8880181f15c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x5f/0x450 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}:
       __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

-> #1 (&priv->j1939_socks_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_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

-> #0 (&priv->active_session_list_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_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
       invoke_softirq kernel/softirq.c:445 [inline]
       __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
       irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
       sysvec_apic_timer_interrupt+0x49/0xc0 arch/x86/kernel/apic/apic.c:1107
       asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649

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 udevd/4433:
 #0: ffffffff8c791b80 (rcu_read_lock){....}-{1:2}, at: __skb_unlink include/linux/skbuff.h:2327 [inline]
 #0: ffffffff8c791b80 (rcu_read_lock){....}-{1:2}, at: __skb_dequeue include/linux/skbuff.h:2342 [inline]
 #0: ffffffff8c791b80 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x38f/0x810 net/core/dev.c:5922
 #1: ffffffff8c791b80 (rcu_read_lock){....}-{1:2}, at: can_receive+0x1ef/0x580 net/can/af_can.c:653
 #2: ffff8880181f15c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline]
 #2: ffff8880181f15c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x5f/0x450 net/can/j1939/socket.c:207

stack backtrace:
CPU: 1 PID: 4433 Comm: udevd Not tainted 6.2.0-rc2-syzkaller-00301-g6bd4755c7c49 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 <TASK>
 __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_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
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x49/0xc0 arch/x86/kernel/apic/apic.c:1107
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0033:0x7f0738a8c9df
Code: cc cc cc cc cc 66 0f 1f 44 00 00 48 89 f8 48 89 f9 49 83 e8 01 49 f7 e1 48 c1 ea 03 48 8d 04 92 48 01 c0 48 29 c1 0f b6 04 0e <41> 88 00 48 89 f8 48 89 d7 48 83 f8 09 77 d2 4c 89 c0 c3 66 66 2e
RSP: 002b:00007ffc3205cc98 EFLAGS: 00000206
RAX: 0000000000000033 RBX: 0000000000000075 RCX: 0000000000000003
RDX: 0000000000000cde RSI: 00007f0738bbf3e0 RDI: 00000000000080af
RBP: 00007ffc3205d1e0 R08: 00007ffc3205d187 R09: cccccccccccccccd
R10: 00000000000080af R11: 0000000000000001 R12: 0000000000000000
R13: 00007ffc3205d188 R14: 0000000000000000 R15: 00007ffc3205d358
 </TASK>