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BUG: KCSAN: data-race in __mod_timer / __mod_timer

write to 0xffff88811aa7b110 of 8 bytes by task 8870 on cpu 1:
 __mod_timer+0x84e/0x990 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/0x340 drivers/net/wireguard/send.c:276
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405
 worker_thread+0x569/0x750 kernel/workqueue.c:3486
 kthread+0x221/0x270 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 0xffff88811aa7b110 of 8 bytes by task 22803 on cpu 0:
 __mod_timer+0x69/0x990 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_packet_consume_data_done drivers/net/wireguard/receive.c:354 [inline]
 wg_packet_rx_poll+0x7b1/0x1090 drivers/net/wireguard/receive.c:474
 __napi_poll+0x61/0x300 net/core/dev.c:7729
 napi_threaded_poll_loop+0x1e8/0x6c0 net/core/dev.c:7849
 napi_threaded_poll+0x193/0x240 net/core/dev.c:7904
 kthread+0x221/0x270 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

value changed: 0x000000010000fc39 -> 0x000000010000fc3f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 22803 Comm: napi/wg2-0 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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