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BUG: KCSAN: data-race in wg_packet_send_staged_packets / wg_packet_send_staged_packets

read to 0xffff888117d5fb28 of 4 bytes by task 1090 on cpu 0:
 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+0x60e/0xac0 drivers/net/wireguard/send.c:388
 wg_xmit+0x5c8/0x6a0 drivers/net/wireguard/device.c:218
 __netdev_start_xmit include/linux/netdevice.h:4882 [inline]
 netdev_start_xmit include/linux/netdevice.h:4896 [inline]
 xmit_one net/core/dev.c:3578 [inline]
 dev_hard_start_xmit+0x119/0x3f0 net/core/dev.c:3594
 __dev_queue_xmit+0xf83/0x1e50 net/core/dev.c:4393
 dev_queue_xmit include/linux/netdevice.h:3095 [inline]
 neigh_connected_output+0x258/0x2c0 net/core/neighbour.c:1594
 neigh_output include/net/neighbour.h:542 [inline]
 ip_finish_output2+0x782/0x8b0 net/ipv4/ip_output.c:235
 ip_finish_output+0x11a/0x2a0 net/ipv4/ip_output.c:323
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip_mc_output+0x269/0x350 net/ipv4/ip_output.c:420
 dst_output include/net/dst.h:450 [inline]
 ip_local_out net/ipv4/ip_output.c:129 [inline]
 ip_send_skb+0x12f/0x140 net/ipv4/ip_output.c:1492
 udp_send_skb+0x6dd/0xa10 net/ipv4/udp.c:980
 udp_sendmsg+0x1257/0x12f0 net/ipv4/udp.c:1268
 inet_sendmsg+0xaf/0xd0 net/ipv4/af_inet.c:853
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x102/0x180 net/socket.c:745
 ____sys_sendmsg+0x312/0x410 net/socket.c:2585
 ___sys_sendmsg net/socket.c:2639 [inline]
 __sys_sendmmsg+0x269/0x500 net/socket.c:2725
 __do_sys_sendmmsg net/socket.c:2754 [inline]
 __se_sys_sendmmsg net/socket.c:2751 [inline]
 __x64_sys_sendmmsg+0x57/0x70 net/socket.c:2751
 x64_sys_call+0xa87/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff888117d5fb28 of 4 bytes by task 1091 on cpu 1:
 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+0x6e5/0xac0 drivers/net/wireguard/send.c:388
 wg_xmit+0x5c8/0x6a0 drivers/net/wireguard/device.c:218
 __netdev_start_xmit include/linux/netdevice.h:4882 [inline]
 netdev_start_xmit include/linux/netdevice.h:4896 [inline]
 xmit_one net/core/dev.c:3578 [inline]
 dev_hard_start_xmit+0x119/0x3f0 net/core/dev.c:3594
 __dev_queue_xmit+0xf83/0x1e50 net/core/dev.c:4393
 dev_queue_xmit include/linux/netdevice.h:3095 [inline]
 neigh_connected_output+0x258/0x2c0 net/core/neighbour.c:1594
 neigh_output include/net/neighbour.h:542 [inline]
 ip_finish_output2+0x782/0x8b0 net/ipv4/ip_output.c:235
 ip_finish_output+0x11a/0x2a0 net/ipv4/ip_output.c:323
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip_mc_output+0x269/0x350 net/ipv4/ip_output.c:420
 dst_output include/net/dst.h:450 [inline]
 ip_local_out net/ipv4/ip_output.c:129 [inline]
 ip_send_skb+0x12f/0x140 net/ipv4/ip_output.c:1492
 udp_send_skb+0x6dd/0xa10 net/ipv4/udp.c:980
 udp_sendmsg+0x1257/0x12f0 net/ipv4/udp.c:1268
 inet_sendmsg+0xaf/0xd0 net/ipv4/af_inet.c:853
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x102/0x180 net/socket.c:745
 ____sys_sendmsg+0x312/0x410 net/socket.c:2585
 ___sys_sendmsg net/socket.c:2639 [inline]
 __sys_sendmmsg+0x269/0x500 net/socket.c:2725
 __do_sys_sendmmsg net/socket.c:2754 [inline]
 __se_sys_sendmmsg net/socket.c:2751 [inline]
 __x64_sys_sendmmsg+0x57/0x70 net/socket.c:2751
 x64_sys_call+0xa87/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1091 Comm: syz-executor.3 Tainted: G        W          6.10.0-rc4-syzkaller-00052-ge5b3efbe1ab1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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