====================================================== WARNING: possible circular locking dependency detected 6.3.0-rc3-syzkaller-00322-g4bdec23f971b #0 Not tainted ------------------------------------------------------ ksoftirqd/0/15 is trying to acquire lock: ffff8880204b5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff8880204b5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff8880204b5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_activate+0x47/0x4b0 net/can/j1939/transport.c:1557 but task is already holding lock: ffff8880207a85c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff8880207a85c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x5f/0x4d0 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:1937 call_netdevice_notifiers_extack net/core/dev.c:1975 [inline] call_netdevice_notifiers net/core/dev.c:1989 [inline] __dev_notify_flags+0x1ea/0x2d0 net/core/dev.c:8568 dev_change_flags+0x11b/0x170 net/core/dev.c:8604 do_setlink+0x9f4/0x3d30 net/core/rtnetlink.c:2833 __rtnl_newlink+0xd69/0x1840 net/core/rtnetlink.c:3623 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3670 rtnetlink_rcv_msg+0x43d/0xd50 net/core/rtnetlink.c:6174 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2574 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0xde/0x190 net/socket.c:747 ____sys_sendmsg+0x71c/0x900 net/socket.c:2501 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2555 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2584 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:1128 j1939_tp_rxtimer+0x3df/0x4b0 net/can/j1939/transport.c:1253 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x5fa/0xbe0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1d4/0x905 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 mod_objcg_state+0x3df/0xa50 mm/memcontrol.c:3228 memcg_slab_post_alloc_hook+0x1e1/0x390 mm/slab.h:555 slab_post_alloc_hook mm/slab.h:777 [inline] slab_alloc_node mm/slub.c:3452 [inline] slab_alloc mm/slub.c:3460 [inline] __kmem_cache_alloc_lru mm/slub.c:3467 [inline] kmem_cache_alloc+0x1af/0x3b0 mm/slub.c:3476 vm_area_dup+0x21/0x1f0 kernel/fork.c:466 dup_mmap+0x67f/0x1230 kernel/fork.c:643 dup_mm kernel/fork.c:1550 [inline] copy_mm kernel/fork.c:1599 [inline] copy_process+0x7082/0x7590 kernel/fork.c:2269 kernel_clone+0xeb/0x890 kernel/fork.c:2684 __do_sys_clone+0xba/0x100 kernel/fork.c:2825 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 -> #0 (&priv->active_session_list_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain kernel/locking/lockdep.c:3832 [inline] __lock_acquire+0x2ec7/0x5d40 kernel/locking/lockdep.c:5056 lock_acquire kernel/locking/lockdep.c:5669 [inline] lock_acquire+0x1af/0x520 kernel/locking/lockdep.c:5634 __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:1557 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x2bf/0x4d0 net/can/j1939/socket.c:208 j1939_simple_txnext net/can/j1939/transport.c:1060 [inline] j1939_tp_txtimer+0x1653/0x2be0 net/can/j1939/transport.c:1153 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x5fa/0xbe0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1d4/0x905 kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x659/0x9e0 kernel/smpboot.c:164 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 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 *** 1 lock held by ksoftirqd/0/15: #0: ffff8880207a85c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #0: ffff8880207a85c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_activate_next+0x5f/0x4d0 net/can/j1939/socket.c:207 stack backtrace: CPU: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 6.3.0-rc3-syzkaller-00322-g4bdec23f971b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain kernel/locking/lockdep.c:3832 [inline] __lock_acquire+0x2ec7/0x5d40 kernel/locking/lockdep.c:5056 lock_acquire kernel/locking/lockdep.c:5669 [inline] lock_acquire+0x1af/0x520 kernel/locking/lockdep.c:5634 __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:1557 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x2bf/0x4d0 net/can/j1939/socket.c:208 j1939_simple_txnext net/can/j1939/transport.c:1060 [inline] j1939_tp_txtimer+0x1653/0x2be0 net/can/j1939/transport.c:1153 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x5fa/0xbe0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1d4/0x905 kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x659/0x9e0 kernel/smpboot.c:164 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 vcan0: j1939_tp_rxtimer: 0xffff88807b1e0c00: rx timeout, send abort vcan0: j1939_tp_rxtimer: 0xffff88807b1e0800: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff88807b1e0c00: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_xtp_rx_abort_one: 0xffff88807b1e0800: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_tp_rxtimer: 0xffff88807a5d0400: rx timeout, send abort vcan0: j1939_tp_rxtimer: 0xffff88807a5d0000: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff88807a5d0400: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_xtp_rx_abort_one: 0xffff88807a5d0000: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_tp_rxtimer: 0xffff88807a167c00: rx timeout, send abort vcan0: j1939_tp_rxtimer: 0xffff8880211b5000: rx timeout, send abort vcan0: j1939_xtp_rx_abort_one: 0xffff88807a167c00: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vcan0: j1939_xtp_rx_abort_one: 0xffff8880211b5000: 0x00000: (3) A timeout occurred and this is the connection abort to close the session.