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BUG: KCSAN: data-race in wg_packet_send_staged_packets / wg_packet_send_staged_packets

read to 0xffff88815e42db28 of 4 bytes by interrupt on cpu 1:
 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_expired_send_persistent_keepalive+0x3c/0x50 drivers/net/wireguard/timers.c:141
 call_timer_fn+0x3a/0x300 kernel/time/timer.c:1792
 expire_timers kernel/time/timer.c:1843 [inline]
 __run_timers kernel/time/timer.c:2408 [inline]
 __run_timer_base+0x417/0x640 kernel/time/timer.c:2419
 run_timer_base kernel/time/timer.c:2428 [inline]
 run_timer_softirq+0x31/0x70 kernel/time/timer.c:2438
 __do_softirq+0xc8/0x285 kernel/softirq.c:554
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:633 [inline]
 irq_exit_rcu+0x3c/0x90 kernel/softirq.c:645
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0x37/0x80 arch/x86/kernel/apic/apic.c:1043
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

write to 0xffff88815e42db28 of 4 bytes by interrupt on cpu 0:
 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_expired_send_persistent_keepalive+0x3c/0x50 drivers/net/wireguard/timers.c:141
 call_timer_fn+0x3a/0x300 kernel/time/timer.c:1792
 expire_timers kernel/time/timer.c:1843 [inline]
 __run_timers kernel/time/timer.c:2408 [inline]
 __run_timer_base+0x417/0x640 kernel/time/timer.c:2419
 run_timer_base kernel/time/timer.c:2428 [inline]
 run_timer_softirq+0x31/0x70 kernel/time/timer.c:2438
 __do_softirq+0xc8/0x285 kernel/softirq.c:554
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:633 [inline]
 irq_exit_rcu+0x3c/0x90 kernel/softirq.c:645
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0x37/0x80 arch/x86/kernel/apic/apic.c:1043
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3238 Comm: syz-fuzzer Tainted: G        W          6.8.0-syzkaller-11567-gb3603fcb79b1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
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