syzbot

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BUG: KCSAN: data-race in wg_packet_send_keepalive / wg_packet_send_staged_packets

write to 0xffff88813253bcb8 of 8 bytes by task 3173 on cpu 0:
 __skb_queue_head_init include/linux/skbuff.h:2162 [inline]
 skb_queue_splice_init include/linux/skbuff.h:2248 [inline]
 wg_packet_send_staged_packets+0xe5/0xad0 drivers/net/wireguard/send.c:350
 wg_xmit+0x5cb/0x680 drivers/net/wireguard/device.c:218
 __netdev_start_xmit include/linux/netdevice.h:4889 [inline]
 netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 xmit_one net/core/dev.c:3573 [inline]
 dev_hard_start_xmit+0x11b/0x3f0 net/core/dev.c:3589
 __dev_queue_xmit+0xf27/0x1e20 net/core/dev.c:4369
 dev_queue_xmit include/linux/netdevice.h:3082 [inline]
 neigh_connected_output+0x231/0x2a0 net/core/neighbour.c:1583
 neigh_output include/net/neighbour.h:542 [inline]
 ip6_finish_output2+0x9c0/0xc50 net/ipv6/ip6_output.c:135
 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline]
 ip6_finish_output+0x3a0/0x4f0 net/ipv6/ip6_output.c:207
 NF_HOOK_COND include/linux/netfilter.h:293 [inline]
 ip6_output+0xeb/0x220 net/ipv6/ip6_output.c:228
 dst_output include/net/dst.h:458 [inline]
 NF_HOOK include/linux/netfilter.h:304 [inline]
 ndisc_send_skb+0x4d2/0x6b0 net/ipv6/ndisc.c:509
 ndisc_send_rs+0x3ab/0x3e0 net/ipv6/ndisc.c:719
 addrconf_dad_completed+0x640/0x8e0 net/ipv6/addrconf.c:4291
 addrconf_dad_work+0x891/0xbc0
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

read to 0xffff88813253bcb8 of 8 bytes by task 3195 on cpu 1:
 skb_queue_empty include/linux/skbuff.h:1798 [inline]
 wg_packet_send_keepalive+0x20/0x100 drivers/net/wireguard/send.c:225
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:186 [inline]
 wg_packet_handshake_receive_worker+0x445/0x5e0 drivers/net/wireguard/receive.c:213
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

value changed: 0xffff888100cd8000 -> 0xffff88813253bcb8

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3195 Comm: kworker/1:5 Not tainted 6.6.0-rc6-syzkaller-00334-g1acfd2bd3f0d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Workqueue: wg-kex-wg2 wg_packet_handshake_receive_worker
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