syzbot

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BUG: KCSAN: data-race in geneve_xmit / geneve_xmit

read-write to 0xffff88802a80b190 of 8 bytes by task 25940 on cpu 1:
 geneve_xmit+0x1122/0x1220 drivers/net/geneve.c:1082
 __netdev_start_xmit include/linux/netdevice.h:4735 [inline]
 netdev_start_xmit include/linux/netdevice.h:4749 [inline]
 xmit_one+0xf9/0x2e0 net/core/dev.c:3564
 dev_hard_start_xmit net/core/dev.c:3580 [inline]
 __dev_queue_xmit+0xeef/0x1510 net/core/dev.c:4140
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4173
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip_finish_output2+0xb09/0xba0 net/ipv4/ip_output.c:230
 __ip_finish_output+0x3d8/0x430 net/ipv4/ip_output.c:308
 ip_finish_output+0x39/0x160 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:290 [inline]
 ip_mc_output+0x304/0x4d0 net/ipv4/ip_output.c:417
 dst_output include/net/dst.h:443 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x6e/0xe0 net/ipv4/ip_output.c:1568
 udp_send_skb+0x619/0x850 net/ipv4/udp.c:948
 udp_sendmsg+0x142c/0x15e0 net/ipv4/udp.c:1235
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:817
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0x352/0x4c0 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmmsg+0x335/0x4b0 net/socket.c:2497
 __do_sys_sendmmsg net/socket.c:2526 [inline]
 __se_sys_sendmmsg net/socket.c:2523 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2523
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read-write to 0xffff88802a80b190 of 8 bytes by task 25908 on cpu 0:
 geneve_xmit+0x1122/0x1220 drivers/net/geneve.c:1082
 __netdev_start_xmit include/linux/netdevice.h:4735 [inline]
 netdev_start_xmit include/linux/netdevice.h:4749 [inline]
 xmit_one+0xf9/0x2e0 net/core/dev.c:3564
 dev_hard_start_xmit net/core/dev.c:3580 [inline]
 __dev_queue_xmit+0xeef/0x1510 net/core/dev.c:4140
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4173
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip_finish_output2+0xb09/0xba0 net/ipv4/ip_output.c:230
 __ip_finish_output+0x3d8/0x430 net/ipv4/ip_output.c:308
 ip_finish_output+0x39/0x160 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:290 [inline]
 ip_mc_output+0x304/0x4d0 net/ipv4/ip_output.c:417
 dst_output include/net/dst.h:443 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x6e/0xe0 net/ipv4/ip_output.c:1568
 udp_send_skb+0x619/0x850 net/ipv4/udp.c:948
 udp_sendmsg+0x142c/0x15e0 net/ipv4/udp.c:1235
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:817
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0x352/0x4c0 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmmsg+0x335/0x4b0 net/socket.c:2497
 __do_sys_sendmmsg net/socket.c:2526 [inline]
 __se_sys_sendmmsg net/socket.c:2523 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2523
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25908 Comm: syz-executor.5 Not tainted 5.10.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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