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BUG: KCSAN: data-race in wg_expired_retransmit_handshake / wg_packet_send_queued_handshake_initiation

read to 0xffff88811a9b0a88 of 4 bytes by interrupt on cpu 1:
 wg_expired_retransmit_handshake+0x2a/0x160 drivers/net/wireguard/timers.c:46
 call_timer_fn+0x3b/0x240 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2374 [inline]
 __run_timer_base+0x40c/0x5f0 kernel/time/timer.c:2386
 run_timer_base kernel/time/timer.c:2395 [inline]
 run_timer_softirq+0x31/0x70 kernel/time/timer.c:2405
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
 sock_has_perm security/selinux/hooks.c:4925 [inline]
 selinux_socket_recvmsg+0x91/0x1e0 security/selinux/hooks.c:5297
 security_socket_recvmsg+0x4c/0x90 security/security.c:4330
 sock_recvmsg+0x38/0x120 net/socket.c:1146
 ____sys_recvmsg+0xf5/0x280 net/socket.c:2904
 ___sys_recvmsg+0x11f/0x3a0 net/socket.c:2946
 __sys_recvmsg net/socket.c:2979 [inline]
 __do_sys_recvmsg net/socket.c:2985 [inline]
 __se_sys_recvmsg net/socket.c:2982 [inline]
 __x64_sys_recvmsg+0xd1/0x160 net/socket.c:2982
 x64_sys_call+0x2b1a/0x3020 arch/x86/include/generated/asm/syscalls_64.h:48
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff88811a9b0a88 of 4 bytes by interrupt on cpu 0:
 wg_packet_send_queued_handshake_initiation+0x32/0x180 drivers/net/wireguard/send.c:59
 wg_expired_new_handshake+0x26/0x30 drivers/net/wireguard/timers.c:104
 call_timer_fn+0x3b/0x240 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2374 [inline]
 __run_timer_base+0x40c/0x5f0 kernel/time/timer.c:2386
 run_timer_base kernel/time/timer.c:2395 [inline]
 run_timer_softirq+0x31/0x70 kernel/time/timer.c:2405
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x121/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000002 -> 0x00000003

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3635 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
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