================================================================== BUG: KCSAN: data-race in ipv6_mc_down / mld_ifc_work write to 0xffff888178cce832 of 1 bytes by task 29599 on cpu 1: mld_ifc_stop_work net/ipv6/mcast.c:1080 [inline] ipv6_mc_down+0x10a/0x280 net/ipv6/mcast.c:2728 addrconf_ifdown+0xe32/0xf10 net/ipv6/addrconf.c:3905 addrconf_notify+0x310/0x980 notifier_call_chain kernel/notifier.c:93 [inline] raw_notifier_call_chain+0x6b/0x1c0 kernel/notifier.c:461 call_netdevice_notifiers_info net/core/dev.c:1962 [inline] call_netdevice_notifiers_extack net/core/dev.c:2000 [inline] call_netdevice_notifiers net/core/dev.c:2014 [inline] dev_close_many+0x1f0/0x2f0 net/core/dev.c:1555 unregister_netdevice_many_notify+0x253/0x1070 net/core/dev.c:10823 rtnl_delete_link net/core/rtnetlink.c:3214 [inline] rtnl_dellink+0x384/0x580 net/core/rtnetlink.c:3266 rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6428 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2549 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6446 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg net/socket.c:748 [inline] ____sys_sendmsg+0x37c/0x4d0 net/socket.c:2494 ___sys_sendmsg net/socket.c:2548 [inline] __sys_sendmsg+0x1e9/0x270 net/socket.c:2577 __do_sys_sendmsg net/socket.c:2586 [inline] __se_sys_sendmsg net/socket.c:2584 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2584 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd write to 0xffff888178cce832 of 1 bytes by task 3189 on cpu 0: mld_ifc_work+0x54c/0x7b0 net/ipv6/mcast.c:2656 process_one_work+0x434/0x860 kernel/workqueue.c:2600 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2751 kthread+0x1d7/0x210 kernel/kthread.c:389 ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 value changed: 0x02 -> 0x00 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 3189 Comm: kworker/0:7 Not tainted 6.5.0-rc7-syzkaller-00004-gf7757129e3de #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: mld mld_ifc_work ==================================================================