====================================================== WARNING: possible circular locking dependency detected 6.7.0-syzkaller-12263-gdbc153fd3c14 #0 Not tainted ------------------------------------------------------ syz-executor.3/23939 is trying to acquire lock: ffff888044c090d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888044c090d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_errqueue+0xaa/0x1a0 net/can/j1939/socket.c:1083 but task is already holding lock: ffff888044c09088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888044c09088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff888044c09088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_cancel_active_session+0x41/0x360 net/can/j1939/transport.c:2183 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&priv->active_session_list_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:356 [inline] j1939_session_list_lock net/can/j1939/transport.c:238 [inline] j1939_session_activate+0x4b/0x4a0 net/can/j1939/transport.c:1564 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x2bc/0x4d0 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1108 [inline] j1939_tp_rxtimer+0x350/0x500 net/can/j1939/transport.c:1236 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x203/0xc20 kernel/time/hrtimer.c:1752 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1769 __do_softirq+0x21a/0x8de kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194 debug_object_deactivate+0x1ec/0x370 lib/debugobjects.c:778 debug_rcu_head_unqueue kernel/rcu/rcu.h:239 [inline] debug_rcu_bhead_unqueue kernel/rcu/tree.c:2908 [inline] kvfree_rcu_bulk+0x12c/0x550 kernel/rcu/tree.c:2985 kvfree_rcu_drain_ready kernel/rcu/tree.c:3166 [inline] kfree_rcu_monitor+0x47b/0x12d0 kernel/rcu/tree.c:3184 process_one_work+0x886/0x15d0 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2706 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 -> #1 (&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:356 [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:1282 j1939_netdev_notify+0x1a2/0x1d0 net/can/j1939/main.c:381 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x130 net/core/dev.c:1966 call_netdevice_notifiers_extack net/core/dev.c:2004 [inline] call_netdevice_notifiers net/core/dev.c:2018 [inline] __dev_notify_flags+0x1f5/0x2e0 net/core/dev.c:8689 dev_change_flags+0x10c/0x160 net/core/dev.c:8725 do_setlink+0x1aac/0x4080 net/core/rtnetlink.c:2903 rtnl_group_changelink net/core/rtnetlink.c:3452 [inline] __rtnl_newlink+0xe04/0x1940 net/core/rtnetlink.c:3711 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3748 rtnetlink_rcv_msg+0x3c7/0xe00 net/core/rtnetlink.c:6615 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x53b/0x810 net/netlink/af_netlink.c:1367 netlink_sendmsg+0x8b7/0xd70 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b -> #0 (&priv->j1939_socks_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2445/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5719 __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:356 [inline] j1939_sk_errqueue+0xaa/0x1a0 net/can/j1939/socket.c:1083 j1939_session_destroy+0x276/0x4f0 net/can/j1939/transport.c:271 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put net/can/j1939/transport.c:299 [inline] j1939_session_deactivate_locked+0x28e/0x330 net/can/j1939/transport.c:1086 j1939_cancel_active_session+0x183/0x360 net/can/j1939/transport.c:2194 j1939_netdev_notify+0x19a/0x1d0 net/can/j1939/main.c:380 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x130 net/core/dev.c:1966 call_netdevice_notifiers_extack net/core/dev.c:2004 [inline] call_netdevice_notifiers net/core/dev.c:2018 [inline] __dev_notify_flags+0x1f5/0x2e0 net/core/dev.c:8689 dev_change_flags+0x10c/0x160 net/core/dev.c:8725 do_setlink+0x1aac/0x4080 net/core/rtnetlink.c:2903 rtnl_group_changelink net/core/rtnetlink.c:3452 [inline] __rtnl_newlink+0xe04/0x1940 net/core/rtnetlink.c:3711 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3748 rtnetlink_rcv_msg+0x3c7/0xe00 net/core/rtnetlink.c:6615 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x53b/0x810 net/netlink/af_netlink.c:1367 netlink_sendmsg+0x8b7/0xd70 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b other info that might help us debug this: Chain exists of: &priv->j1939_socks_lock --> &jsk->sk_session_queue_lock --> &priv->active_session_list_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&priv->active_session_list_lock); lock(&jsk->sk_session_queue_lock); lock(&priv->active_session_list_lock); lock(&priv->j1939_socks_lock); *** DEADLOCK *** 2 locks held by syz-executor.3/23939: #0: ffffffff8ecbc728 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8ecbc728 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xe00 net/core/rtnetlink.c:6612 #1: ffff888044c09088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff888044c09088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] #1: ffff888044c09088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_cancel_active_session+0x41/0x360 net/can/j1939/transport.c:2183 stack backtrace: CPU: 0 PID: 23939 Comm: syz-executor.3 Not tainted 6.7.0-syzkaller-12263-gdbc153fd3c14 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x317/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2445/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5719 __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:356 [inline] j1939_sk_errqueue+0xaa/0x1a0 net/can/j1939/socket.c:1083 j1939_session_destroy+0x276/0x4f0 net/can/j1939/transport.c:271 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put net/can/j1939/transport.c:299 [inline] j1939_session_deactivate_locked+0x28e/0x330 net/can/j1939/transport.c:1086 j1939_cancel_active_session+0x183/0x360 net/can/j1939/transport.c:2194 j1939_netdev_notify+0x19a/0x1d0 net/can/j1939/main.c:380 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x130 net/core/dev.c:1966 call_netdevice_notifiers_extack net/core/dev.c:2004 [inline] call_netdevice_notifiers net/core/dev.c:2018 [inline] __dev_notify_flags+0x1f5/0x2e0 net/core/dev.c:8689 dev_change_flags+0x10c/0x160 net/core/dev.c:8725 do_setlink+0x1aac/0x4080 net/core/rtnetlink.c:2903 rtnl_group_changelink net/core/rtnetlink.c:3452 [inline] __rtnl_newlink+0xe04/0x1940 net/core/rtnetlink.c:3711 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3748 rtnetlink_rcv_msg+0x3c7/0xe00 net/core/rtnetlink.c:6615 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x53b/0x810 net/netlink/af_netlink.c:1367 netlink_sendmsg+0x8b7/0xd70 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f9d2367cda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9d244340c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f9d237abf80 RCX: 00007f9d2367cda9 RDX: 0000000000000000 RSI: 0000000020006440 RDI: 0000000000000006 RBP: 00007f9d236c947a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f9d237abf80 R15: 00007fff58eedf88