syzbot

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BUG: KCSAN: data-race in wg_packet_send_staged_packets / wg_packet_send_staged_packets

read to 0xffff888158f36b28 of 4 bytes by task 1942 on cpu 0:
 wg_cpumask_next_online drivers/net/wireguard/queueing.h:127 [inline]
 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+0x614/0xae0 drivers/net/wireguard/send.c:388
 wg_packet_send_keepalive+0xe2/0x100 drivers/net/wireguard/send.c:239
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline]
 wg_packet_handshake_receive_worker+0x449/0x5f0 drivers/net/wireguard/receive.c:213
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0x465/0x990 kernel/workqueue.c:3335
 worker_thread+0x526/0x730 kernel/workqueue.c:3416
 kthread+0x1d1/0x210 kernel/kthread.c:388
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

write to 0xffff888158f36b28 of 4 bytes by task 10981 on cpu 1:
 wg_cpumask_next_online drivers/net/wireguard/queueing.h:130 [inline]
 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+0x6f9/0xae0 drivers/net/wireguard/send.c:388
 wg_packet_send_keepalive+0xe2/0x100 drivers/net/wireguard/send.c:239
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline]
 wg_packet_handshake_receive_worker+0x449/0x5f0 drivers/net/wireguard/receive.c:213
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0x465/0x990 kernel/workqueue.c:3335
 worker_thread+0x526/0x730 kernel/workqueue.c:3416
 kthread+0x1d1/0x210 kernel/kthread.c:388
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10981 Comm: kworker/1:22 Tainted: G        W          6.9.0-rc4-syzkaller-00034-g4b6b51322118 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: wg-kex-wg2 wg_packet_handshake_receive_worker
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