====================================================== WARNING: possible circular locking dependency detected 6.17.0-rc1-syzkaller-00029-g91325f31afc1 #0 Not tainted ------------------------------------------------------ dhcpcd/5522 is trying to acquire lock: ffffffff99fc2398 (&net->xdp.lock){+.+.}-{4:4}, at: xsk_notifier+0x89/0x230 net/xdp/xsk.c:1664 but task is already holding lock: ffff888062718d28 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2758 [inline] ffff888062718d28 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] ffff888062718d28 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: dev_change_flags+0x113/0x260 net/core/dev_api.c:67 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&dev_instance_lock_key#20){+.+.}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1360 kernel/locking/mutex.c:760 netdev_lock include/linux/netdevice.h:2758 [inline] netdev_lock_ops include/net/netdev_lock.h:42 [inline] xsk_bind+0x2f7/0xf90 net/xdp/xsk.c:1193 __sys_bind_socket net/socket.c:1858 [inline] __sys_bind+0x2c6/0x3e0 net/socket.c:1889 __do_sys_bind net/socket.c:1894 [inline] __se_sys_bind net/socket.c:1892 [inline] __x64_sys_bind+0x7a/0x90 net/socket.c:1892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&xs->mutex){+.+.}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1360 kernel/locking/mutex.c:760 xsk_notifier+0xd5/0x230 net/xdp/xsk.c:1668 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] unregister_netdevice_many_notify+0x14d7/0x1ff0 net/core/dev.c:12148 rtnl_delete_link net/core/rtnetlink.c:3513 [inline] rtnl_dellink+0x488/0x710 net/core/rtnetlink.c:3555 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6946 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&net->xdp.lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1360 kernel/locking/mutex.c:760 xsk_notifier+0x89/0x230 net/xdp/xsk.c:1664 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] unregister_netdevice_many_notify+0x14d7/0x1ff0 net/core/dev.c:12148 unregister_netdevice_many net/core/dev.c:12211 [inline] unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:12055 register_netdevice+0x1689/0x1ae0 net/core/dev.c:11233 bpq_new_device drivers/net/hamradio/bpqether.c:481 [inline] bpq_device_event+0x491/0x600 drivers/net/hamradio/bpqether.c:523 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9600 dev_change_flags+0x130/0x260 net/core/dev_api.c:68 devinet_ioctl+0xbb4/0x1b50 net/ipv4/devinet.c:1200 inet_ioctl+0x3c0/0x4c0 net/ipv4/af_inet.c:1001 sock_do_ioctl+0xdc/0x300 net/socket.c:1238 sock_ioctl+0x576/0x790 net/socket.c:1359 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &net->xdp.lock --> &xs->mutex --> &dev_instance_lock_key#20 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&dev_instance_lock_key#20); lock(&xs->mutex); lock(&dev_instance_lock_key#20); lock(&net->xdp.lock); *** DEADLOCK *** 2 locks held by dhcpcd/5522: #0: ffffffff8f537c88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f537c88 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x323/0x1b50 net/ipv4/devinet.c:1121 #1: ffff888062718d28 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2758 [inline] #1: ffff888062718d28 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #1: ffff888062718d28 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: dev_change_flags+0x113/0x260 net/core/dev_api.c:67 stack backtrace: CPU: 1 UID: 0 PID: 5522 Comm: dhcpcd Not tainted 6.17.0-rc1-syzkaller-00029-g91325f31afc1 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1360 kernel/locking/mutex.c:760 xsk_notifier+0x89/0x230 net/xdp/xsk.c:1664 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] unregister_netdevice_many_notify+0x14d7/0x1ff0 net/core/dev.c:12148 unregister_netdevice_many net/core/dev.c:12211 [inline] unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:12055 register_netdevice+0x1689/0x1ae0 net/core/dev.c:11233 bpq_new_device drivers/net/hamradio/bpqether.c:481 [inline] bpq_device_event+0x491/0x600 drivers/net/hamradio/bpqether.c:523 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9600 dev_change_flags+0x130/0x260 net/core/dev_api.c:68 devinet_ioctl+0xbb4/0x1b50 net/ipv4/devinet.c:1200 inet_ioctl+0x3c0/0x4c0 net/ipv4/af_inet.c:1001 sock_do_ioctl+0xdc/0x300 net/socket.c:1238 sock_ioctl+0x576/0x790 net/socket.c:1359 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9b85bc0378 Code: 00 00 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 07 89 d0 c3 0f 1f 40 00 48 8b 15 49 3a 0d RSP: 002b:00007ffdd9c500b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000019 RCX: 00007f9b85bc0378 RDX: 00007ffdd9c602b0 RSI: 0000000000008914 RDI: 0000000000000019 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdd9c70450 R13: 00007f9b85ac06c8 R14: 0000000000000028 R15: 0000000000008914