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BUG: KCSAN: data-race in __mod_timer / __mod_timer

write to 0xffff88811b08f180 of 8 bytes by task 4272 on cpu 1:
 __mod_timer+0x670/0x9d0 kernel/time/timer.c:1126
 mod_timer+0x1f/0x30 kernel/time/timer.c:1195
 mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
 wg_timers_any_authenticated_packet_traversal+0xd0/0x100 drivers/net/wireguard/timers.c:218
 wg_packet_create_data_done drivers/net/wireguard/send.c:247 [inline]
 wg_packet_tx_worker+0xeb/0x330 drivers/net/wireguard/send.c:276
 process_one_work kernel/workqueue.c:3275 [inline]
 process_scheduled_works+0x4de/0x9e0 kernel/workqueue.c:3358
 worker_thread+0x581/0x770 kernel/workqueue.c:3439
 kthread+0x22a/0x280 kernel/kthread.c:467
 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff88811b08f180 of 8 bytes by task 3411 on cpu 0:
 __mod_timer+0x69/0x9d0 kernel/time/timer.c:1038
 mod_timer+0x1f/0x30 kernel/time/timer.c:1195
 mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
 wg_timers_any_authenticated_packet_traversal+0xd0/0x100 drivers/net/wireguard/timers.c:218
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:202 [inline]
 wg_packet_handshake_receive_worker+0x4c3/0x5d0 drivers/net/wireguard/receive.c:213
 process_one_work kernel/workqueue.c:3275 [inline]
 process_scheduled_works+0x4de/0x9e0 kernel/workqueue.c:3358
 worker_thread+0x581/0x770 kernel/workqueue.c:3439
 kthread+0x22a/0x280 kernel/kthread.c:467
 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000fffff524 -> 0x00000000fffff55f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3411 Comm: kworker/0:5 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: wg-kex-wg0 wg_packet_handshake_receive_worker
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