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BUG: KCSAN: data-race in kick_pool_pick / wq_worker_running

read-write to 0xffff888237c2b0a4 of 4 bytes by task 3530 on cpu 0:
 wq_worker_running+0x9c/0x120 kernel/workqueue.c:1465
 schedule_timeout+0xca/0x180 kernel/time/sleep_timeout.c:99
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common+0xef/0x1d0 kernel/sched/completion.c:132
 usb_start_wait_urb+0x12c/0x220 drivers/usb/core/message.c:72
 usb_internal_control_msg drivers/usb/core/message.c:117 [inline]
 usb_control_msg+0x182/0x240 drivers/usb/core/message.c:167
 get_port_status drivers/usb/core/hub.c:610 [inline]
 hub_ext_port_status+0xb4/0x410 drivers/usb/core/hub.c:627
 usb_hub_port_status drivers/usb/core/hub.c:677 [inline]
 port_event drivers/usb/core/hub.c:5779 [inline]
 hub_event+0x47e/0x2aa0 drivers/usb/core/hub.c:5971
 process_one_work kernel/workqueue.c:3396 [inline]
 process_scheduled_works+0x56a/0xa50 kernel/workqueue.c:3479
 worker_thread+0x569/0x750 kernel/workqueue.c:3560
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237c2b0a4 of 4 bytes by task 4539 on cpu 1:
 need_more_worker kernel/workqueue.c:954 [inline]
 kick_pool_pick+0x5f/0x310 kernel/workqueue.c:1284
 __queue_work+0x913/0xbd0 kernel/workqueue.c:2449
 queue_work_on+0xa9/0x140 kernel/workqueue.c:2501
 wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:173 [inline]
 wg_packet_create_data drivers/net/wireguard/send.c:320 [inline]
 wg_packet_send_staged_packets+0x9f3/0xcc0 drivers/net/wireguard/send.c:388
 wg_xmit+0x5e5/0x6d0 drivers/net/wireguard/device.c:218
 __netdev_start_xmit include/linux/netdevice.h:5432 [inline]
 netdev_start_xmit include/linux/netdevice.h:5441 [inline]
 xmit_one net/core/dev.c:3953 [inline]
 dev_hard_start_xmit+0x10c/0x380 net/core/dev.c:3969
 __dev_queue_xmit+0xbfd/0x1ec0 net/core/dev.c:4958
 dev_queue_xmit include/linux/netdevice.h:3464 [inline]
 neigh_connected_output+0x251/0x2c0 net/core/neighbour.c:1645
 neigh_output include/net/neighbour.h:560 [inline]
 ip_finish_output2+0x792/0x8a0 net/ipv4/ip_output.c:236
 __ip_finish_output net/ipv4/ip_output.c:-1 [inline]
 ip_finish_output+0x112/0x290 net/ipv4/ip_output.c:324
 NF_HOOK_COND include/linux/netfilter.h:314 [inline]
 ip_mc_output+0x25f/0x370 net/ipv4/ip_output.c:421
 dst_output include/net/dst.h:471 [inline]
 ip_local_out net/ipv4/ip_output.c:131 [inline]
 ip_send_skb+0x139/0x140 net/ipv4/ip_output.c:1515
 udp_send_skb+0x542/0x7b0 net/ipv4/udp.c:1183
 udp_sendmsg+0x1094/0x14e0 net/ipv4/udp.c:1465
 inet_sendmsg+0xac/0xd0 net/ipv4/af_inet.c:865
 sock_sendmsg_nosec net/socket.c:801 [inline]
 __sock_sendmsg net/socket.c:815 [inline]
 ____sys_sendmsg+0x4e8/0x580 net/socket.c:2713
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2767
 __sys_sendmmsg+0x185/0x320 net/socket.c:2856
 __do_sys_sendmmsg net/socket.c:2883 [inline]
 __se_sys_sendmmsg net/socket.c:2880 [inline]
 __x64_sys_sendmmsg+0x57/0x70 net/socket.c:2880
 x64_sys_call+0x1fb4/0x2550 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4539 Comm: syz.3.248 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
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