IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready ====================================================== WARNING: possible circular locking dependency detected 6.1.69-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor320/6247 is trying to acquire lock: ffff888074ef50d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff888074ef50d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_errqueue+0x92/0x140 net/can/j1939/socket.c:1081 but task is already holding lock: ffff888074ef5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff888074ef5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff888074ef5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_cancel_active_session+0x43/0x480 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}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __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/0x3d0 net/can/j1939/transport.c:1564 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x268/0x3e0 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1108 [inline] j1939_session_completed net/can/j1939/transport.c:1222 [inline] j1939_xtp_rx_eoma_one net/can/j1939/transport.c:1395 [inline] j1939_xtp_rx_eoma+0x323/0x530 net/can/j1939/transport.c:1410 j1939_tp_cmd_recv net/can/j1939/transport.c:2099 [inline] j1939_tp_recv+0x833/0x1000 net/can/j1939/transport.c:2144 j1939_can_recv+0x72e/0xb10 net/can/j1939/main.c:112 deliver net/can/af_can.c:573 [inline] can_rcv_filter+0x349/0x7c0 net/can/af_can.c:607 can_receive+0x319/0x470 net/can/af_can.c:664 can_rcv+0x140/0x260 net/can/af_can.c:688 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5639 process_backlog+0x381/0x760 net/core/dev.c:5967 __napi_poll+0xc7/0x470 net/core/dev.c:6534 napi_poll net/core/dev.c:6601 [inline] net_rx_action+0x70f/0xeb0 net/core/dev.c:6712 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 run_ksoftirqd+0xc1/0x120 kernel/softirq.c:934 smpboot_thread_fn+0x52c/0xa30 kernel/smpboot.c:164 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 -> #1 (&jsk->sk_session_queue_lock){+.-.}-{2:2}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __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+0x3a/0x240 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0xe9/0x150 net/can/j1939/socket.c:1280 j1939_netdev_notify+0x209/0x2e0 net/can/j1939/main.c:381 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455 __dev_notify_flags+0x304/0x610 dev_change_flags+0xe7/0x190 net/core/dev.c:8655 do_setlink+0xf5d/0x3e60 net/core/rtnetlink.c:2808 __rtnl_newlink net/core/rtnetlink.c:3576 [inline] rtnl_newlink+0x172c/0x2050 net/core/rtnetlink.c:3623 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6122 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2499 ___sys_sendmsg net/socket.c:2553 [inline] __sys_sendmsg+0x2a9/0x390 net/socket.c:2582 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&priv->j1939_socks_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __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+0x92/0x140 net/can/j1939/socket.c:1081 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put+0x100/0x460 net/can/j1939/transport.c:299 j1939_session_deactivate_locked net/can/j1939/transport.c:1086 [inline] j1939_cancel_active_session+0x350/0x480 net/can/j1939/transport.c:2194 j1939_netdev_notify+0x201/0x2e0 net/can/j1939/main.c:380 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455 __dev_notify_flags+0x304/0x610 dev_change_flags+0xe7/0x190 net/core/dev.c:8655 do_setlink+0xf5d/0x3e60 net/core/rtnetlink.c:2808 __rtnl_newlink net/core/rtnetlink.c:3576 [inline] rtnl_newlink+0x172c/0x2050 net/core/rtnetlink.c:3623 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6122 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2499 ___sys_sendmsg net/socket.c:2553 [inline] __sys_sendmsg+0x2a9/0x390 net/socket.c:2582 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd 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-executor320/6247: #0: ffffffff8e294e68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e294e68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6119 #1: ffff888074ef5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #1: ffff888074ef5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] #1: ffff888074ef5088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_cancel_active_session+0x43/0x480 net/can/j1939/transport.c:2183 stack backtrace: CPU: 1 PID: 6247 Comm: syz-executor320 Not tainted 6.1.69-syzkaller #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+0x1e3/0x2cb lib/dump_stack.c:106 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __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+0x92/0x140 net/can/j1939/socket.c:1081 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put+0x100/0x460 net/can/j1939/transport.c:299 j1939_session_deactivate_locked net/can/j1939/transport.c:1086 [inline] j1939_cancel_active_session+0x350/0x480 net/can/j1939/transport.c:2194 j1939_netdev_notify+0x201/0x2e0 net/can/j1939/main.c:380 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:455 __dev_notify_flags+0x304/0x610 dev_change_flags+0xe7/0x190 net/core/dev.c:8655 do_setlink+0xf5d/0x3e60 net/core/rtnetlink.c:2808 __rtnl_newlink net/core/rtnetlink.c:3576 [inline] rtnl_newlink+0x172c/0x2050 net/core/rtnetlink.c:3623 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6122 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2499 ___sys_sendmsg net/socket.c:2553 [inline] __sys_sendmsg+0x2a9/0x390 net/socket.c:2582 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f91ed11e549 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 1c 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:00007ffcb19f1168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f91ed11e549 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000007 RBP: 0000000000000000 R08: 00007ffcb19f1210 R09: 00007ffcb19f1210 R10: 00007ffcb19f1210 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000