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BUG: KCSAN: data-race in ip_tunnel_xmit / ip_tunnel_xmit

read to 0xffff888130eaa178 of 8 bytes by task 1850 on cpu 1:
 ip_tunnel_xmit+0x960/0x1220 net/ipv4/ip_tunnel.c:762
 ipip_tunnel_xmit+0x266/0x2d0 net/ipv4/ipip.c:307
 __netdev_start_xmit include/linux/netdevice.h:4685 [inline]
 netdev_start_xmit include/linux/netdevice.h:4699 [inline]
 xmit_one+0x105/0x2f0 net/core/dev.c:3473
 dev_hard_start_xmit net/core/dev.c:3489 [inline]
 __dev_queue_xmit+0x86d/0xfa0 net/core/dev.c:4116
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4149
 neigh_connected_output+0x264/0x2a0 net/core/neighbour.c:1557
 neigh_output include/net/neighbour.h:549 [inline]
 ip_finish_output2+0x741/0xb70 net/ipv4/ip_output.c:228
 ip_finish_output+0xfb/0x240 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out+0x60/0x80 net/ipv4/ip_output.c:126
 iptunnel_xmit+0x349/0x4f0 net/ipv4/ip_tunnel_core.c:82
 udp_tunnel_xmit_skb+0x16f/0x180 net/ipv4/udp_tunnel_core.c:171
 send4+0x4d2/0x510 drivers/net/wireguard/socket.c:85
 wg_socket_send_skb_to_peer+0x92/0x130 drivers/net/wireguard/socket.c:174
 wg_socket_send_buffer_to_peer+0xf7/0x120 drivers/net/wireguard/socket.c:199
 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline]
 wg_packet_handshake_send_worker+0x109/0x150 drivers/net/wireguard/send.c:51
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

write to 0xffff888130eaa178 of 8 bytes by task 10200 on cpu 0:
 ip_tunnel_xmit+0x972/0x1220 net/ipv4/ip_tunnel.c:762
 ipip_tunnel_xmit+0x266/0x2d0 net/ipv4/ipip.c:307
 __netdev_start_xmit include/linux/netdevice.h:4685 [inline]
 netdev_start_xmit include/linux/netdevice.h:4699 [inline]
 xmit_one+0x105/0x2f0 net/core/dev.c:3473
 dev_hard_start_xmit net/core/dev.c:3489 [inline]
 __dev_queue_xmit+0x86d/0xfa0 net/core/dev.c:4116
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4149
 neigh_connected_output+0x264/0x2a0 net/core/neighbour.c:1557
 neigh_output include/net/neighbour.h:549 [inline]
 ip_finish_output2+0x741/0xb70 net/ipv4/ip_output.c:228
 ip_finish_output+0xfb/0x240 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out+0x60/0x80 net/ipv4/ip_output.c:126
 iptunnel_xmit+0x349/0x4f0 net/ipv4/ip_tunnel_core.c:82
 udp_tunnel_xmit_skb+0x16f/0x180 net/ipv4/udp_tunnel_core.c:171
 send4+0x4d2/0x510 drivers/net/wireguard/socket.c:85
 wg_socket_send_skb_to_peer+0x92/0x130 drivers/net/wireguard/socket.c:174
 wg_socket_send_buffer_to_peer+0xf7/0x120 drivers/net/wireguard/socket.c:199
 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline]
 wg_packet_handshake_send_worker+0x109/0x150 drivers/net/wireguard/send.c:51
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

value changed: 0x0000000000000269 -> 0x000000000000026a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10200 Comm: kworker/u4:2 Not tainted 5.17.0-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker
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