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BUG: KCSAN: data-race in __mod_timer / __mod_timer

write to 0xffff88811a1cb120 of 8 bytes by task 18951 on cpu 1:
 __mod_timer+0x86a/0x9c0 kernel/time/timer.c:1078
 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:3257 [inline]
 process_scheduled_works+0x4cd/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x6bc/0x8b0 kernel/workqueue.c:3421
 kthread+0x488/0x510 kernel/kthread.c:463
 ret_from_fork+0x148/0x280 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

read to 0xffff88811a1cb120 of 8 bytes by task 18225 on cpu 0:
 __mod_timer+0x69/0x9c0 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:3257 [inline]
 process_scheduled_works+0x4cd/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x6bc/0x8b0 kernel/workqueue.c:3421
 kthread+0x488/0x510 kernel/kthread.c:463
 ret_from_fork+0x148/0x280 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

value changed: 0x000000010004be2d -> 0x000000010004be2e

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 18225 Comm: kworker/0:3 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: wg-kex-wg0 wg_packet_handshake_receive_worker
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