vcan0: j1939_xtp_rx_abort_one: 0xffff888024cf8c00: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. ====================================================== WARNING: possible circular locking dependency detected 5.16.0-rc8-syzkaller #0 Not tainted ------------------------------------------------------ ksoftirqd/3/31 is trying to acquire lock: ffff88804d4f5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] ffff88804d4f5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff88804d4f5088 (&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: ffff8880681075c0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] ffff8880681075c0 (&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:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2002 call_netdevice_notifiers_extack net/core/dev.c:2014 [inline] call_netdevice_notifiers net/core/dev.c:2028 [inline] __dev_notify_flags+0x1da/0x2b0 net/core/dev.c:8836 dev_change_flags+0x112/0x170 net/core/dev.c:8872 do_setlink+0x96d/0x3970 net/core/rtnetlink.c:2719 rtnl_group_changelink net/core/rtnetlink.c:3242 [inline] __rtnl_newlink+0xc06/0x1750 net/core/rtnetlink.c:3396 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3506 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2496 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c -> #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+0x15e/0x1aa 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 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] default_idle+0xb/0x10 arch/x86/kernel/process.c:733 default_idle_call+0x87/0xd0 kernel/sched/idle.c:112 cpuidle_idle_call kernel/sched/idle.c:194 [inline] do_idle+0x401/0x590 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x265/0x340 arch/x86/kernel/smpboot.c:272 secondary_startup_64_no_verify+0xb0/0xbb -> #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+0x2a2c/0x5470 kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __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+0x2e/0x35 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:5465 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5579 process_backlog+0x2a5/0x6c0 net/core/dev.c:6455 __napi_poll+0xaf/0x440 net/core/dev.c:7023 napi_poll net/core/dev.c:7090 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7177 __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+0x405/0x4f0 kernel/kthread.c:327 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/3/31: #0: ffffffff8bb83da0 (rcu_read_lock){....}-{1:2}, at: __skb_unlink include/linux/skbuff.h:2137 [inline] #0: ffffffff8bb83da0 (rcu_read_lock){....}-{1:2}, at: __skb_dequeue include/linux/skbuff.h:2152 [inline] #0: ffffffff8bb83da0 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x250/0x6c0 net/core/dev.c:6453 #1: ffffffff8bb83da0 (rcu_read_lock){....}-{1:2}, at: can_receive+0x1ef/0x580 net/can/af_can.c:655 #2: ffff8880681075c0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline] #2: ffff8880681075c0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x56/0x460 net/can/j1939/socket.c:204 stack backtrace: CPU: 3 PID: 31 Comm: ksoftirqd/3 Not tainted 5.16.0-rc8-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 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+0x2a2c/0x5470 kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __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+0x2e/0x35 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:5465 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5579 process_backlog+0x2a5/0x6c0 net/core/dev.c:6455 __napi_poll+0xaf/0x440 net/core/dev.c:7023 napi_poll net/core/dev.c:7090 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7177 __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+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 vcan0: j1939_tp_rxtimer: 0xffff888018293c00: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff8880638c8400: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_tp_rxtimer: 0xffff888018293c00: abort rx timeout. Force session deactivation