IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready ====================================================== WARNING: possible circular locking dependency detected 6.2.0-rc3-syzkaller-00009-g5a41237ad1d4 #0 Not tainted ------------------------------------------------------ syz-executor.3/9744 is trying to acquire lock: ffff888078d1f5c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff888078d1f5c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_drop_all+0x3f/0x250 net/can/j1939/socket.c:139 but task is already holding lock: ffff88808196d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88808196d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_netdev_event_netdown+0x2d/0x160 net/can/j1939/socket.c:1269 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&priv->j1939_socks_lock){+.-.}-{2:2}: lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5668 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_sk_errqueue+0x92/0x160 net/can/j1939/socket.c:1081 j1939_tp_rxtimer+0x479/0xa20 net/can/j1939/transport.c:1257 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x50b/0xa60 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x1a1/0x580 kernel/time/hrtimer.c:1766 __do_softirq+0x277/0x75b kernel/softirq.c:571 run_ksoftirqd+0xc1/0x120 kernel/softirq.c:934 smpboot_thread_fn+0x533/0xa10 kernel/smpboot.c:164 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 -> #1 (&priv->active_session_list_lock){+.-.}-{2:2}: lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5668 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 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+0x4d/0x450 net/can/j1939/transport.c:1561 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x279/0x3f0 net/can/j1939/socket.c:208 j1939_xtp_rx_eoma net/can/j1939/transport.c:1407 [inline] j1939_tp_cmd_recv net/can/j1939/transport.c:2096 [inline] j1939_tp_recv+0xc83/0x14f0 net/can/j1939/transport.c:2141 j1939_can_recv+0x700/0xb50 net/can/j1939/main.c:112 deliver net/can/af_can.c:572 [inline] can_rcv_filter+0x35e/0x800 net/can/af_can.c:606 can_receive+0x2e8/0x410 net/can/af_can.c:663 can_rcv+0x13c/0x250 net/can/af_can.c:687 __netif_receive_skb_one_core net/core/dev.c:5482 [inline] __netif_receive_skb+0x1c5/0x500 net/core/dev.c:5596 process_backlog+0x568/0x920 net/core/dev.c:5924 __napi_poll+0xbe/0x4b0 net/core/dev.c:6485 napi_poll net/core/dev.c:6552 [inline] net_rx_action+0x76c/0x1100 net/core/dev.c:6663 __do_softirq+0x277/0x75b kernel/softirq.c:571 run_ksoftirqd+0xc1/0x120 kernel/softirq.c:934 smpboot_thread_fn+0x533/0xa10 kernel/smpboot.c:164 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 -> #0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain+0x184a/0x6470 kernel/locking/lockdep.c:3831 __lock_acquire+0x1292/0x1f60 kernel/locking/lockdep.c:5055 lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5668 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_sk_queue_drop_all+0x3f/0x250 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0xf5/0x160 net/can/j1939/socket.c:1275 j1939_netdev_notify+0x204/0x330 net/can/j1939/main.c:379 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:455 __dev_notify_flags+0x339/0x630 dev_change_flags+0xe8/0x190 net/core/dev.c:8607 do_setlink+0xf36/0x3f10 net/core/rtnetlink.c:2827 __rtnl_newlink net/core/rtnetlink.c:3590 [inline] rtnl_newlink+0x1856/0x20a0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x7ca/0xec0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x1f0/0x470 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x7e7/0x9c0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x9b3/0xcd0 net/netlink/af_netlink.c:1932 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0x597/0x8e0 net/socket.c:2476 ___sys_sendmsg net/socket.c:2530 [inline] __sys_sendmsg+0x28e/0x390 net/socket.c:2559 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &jsk->sk_session_queue_lock --> &priv->active_session_list_lock --> &priv->j1939_socks_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&priv->j1939_socks_lock); lock(&priv->active_session_list_lock); lock(&priv->j1939_socks_lock); lock(&jsk->sk_session_queue_lock); *** DEADLOCK *** 2 locks held by syz-executor.3/9744: #0: ffffffff8e664848 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:75 [inline] #0: ffffffff8e664848 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x773/0xec0 net/core/rtnetlink.c:6138 #1: ffff88808196d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #1: ffff88808196d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_netdev_event_netdown+0x2d/0x160 net/can/j1939/socket.c:1269 stack backtrace: CPU: 1 PID: 9744 Comm: syz-executor.3 Not tainted 6.2.0-rc3-syzkaller-00009-g5a41237ad1d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2f9/0x3b0 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+0x184a/0x6470 kernel/locking/lockdep.c:3831 __lock_acquire+0x1292/0x1f60 kernel/locking/lockdep.c:5055 lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5668 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:355 [inline] j1939_sk_queue_drop_all+0x3f/0x250 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0xf5/0x160 net/can/j1939/socket.c:1275 j1939_netdev_notify+0x204/0x330 net/can/j1939/main.c:379 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:455 __dev_notify_flags+0x339/0x630 dev_change_flags+0xe8/0x190 net/core/dev.c:8607 do_setlink+0xf36/0x3f10 net/core/rtnetlink.c:2827 __rtnl_newlink net/core/rtnetlink.c:3590 [inline] rtnl_newlink+0x1856/0x20a0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x7ca/0xec0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x1f0/0x470 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x7e7/0x9c0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x9b3/0xcd0 net/netlink/af_netlink.c:1932 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0x597/0x8e0 net/socket.c:2476 ___sys_sendmsg net/socket.c:2530 [inline] __sys_sendmsg+0x28e/0x390 net/socket.c:2559 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fe44808c0c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe448d07168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fe4481abf80 RCX: 00007fe44808c0c9 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000006 RBP: 00007fe4480e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc6f69a4cf R14: 00007fe448d07300 R15: 0000000000022000