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BUG: KCSAN: data-race in __neigh_event_send / neigh_resolve_output

write to 0xffff88813bdba284 of 1 bytes by task 12126 on cpu 1:
 __neigh_event_send+0x458/0xbc0 net/core/neighbour.c:1201
 neigh_event_send_probe include/net/neighbour.h:470 [inline]
 neigh_event_send include/net/neighbour.h:476 [inline]
 neigh_resolve_output+0x110/0x450 net/core/neighbour.c:1555
 neigh_output include/net/neighbour.h:546 [inline]
 ip6_finish_output2+0xa12/0xc30 net/ipv6/ip6_output.c:134
 ip6_fragment+0x101b/0x1270 net/ipv6/ip6_output.c:1007
 __ip6_finish_output net/ipv6/ip6_output.c:193 [inline]
 ip6_finish_output+0x3b4/0x4f0 net/ipv6/ip6_output.c:206
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:227
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip6_xmit+0x79d/0xb50 net/ipv6/ip6_output.c:343
 sctp_v6_xmit+0x413/0x730 net/sctp/ipv6.c:250
 sctp_packet_transmit+0x13aa/0x1480 net/sctp/output.c:653
 sctp_packet_singleton+0x118/0x170 net/sctp/outqueue.c:783
 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline]
 sctp_outq_flush+0x300/0x1920 net/sctp/outqueue.c:1212
 sctp_outq_uncork+0x54/0x60 net/sctp/outqueue.c:764
 sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
 sctp_do_sm+0x2c15/0x2ed0 net/sctp/sm_sideeffect.c:1170
 sctp_primitive_ASSOCIATE+0x6e/0x80 net/sctp/primitive.c:73
 sctp_sendmsg_to_asoc+0x85f/0xb90 net/sctp/socket.c:1835
 sctp_sendmsg+0x1280/0x1840 net/sctp/socket.c:2025
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:827
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 __sys_sendto+0x22d/0x2d0 net/socket.c:2117
 __do_sys_sendto net/socket.c:2129 [inline]
 __se_sys_sendto net/socket.c:2125 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:2125
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813bdba284 of 1 bytes by task 12133 on cpu 0:
 neigh_event_send_probe include/net/neighbour.h:469 [inline]
 neigh_event_send include/net/neighbour.h:476 [inline]
 neigh_resolve_output+0x6f/0x450 net/core/neighbour.c:1555
 neigh_output include/net/neighbour.h:546 [inline]
 ip6_finish_output2+0xa12/0xc30 net/ipv6/ip6_output.c:134
 ip6_fragment+0x101b/0x1270 net/ipv6/ip6_output.c:1007
 __ip6_finish_output net/ipv6/ip6_output.c:193 [inline]
 ip6_finish_output+0x3b4/0x4f0 net/ipv6/ip6_output.c:206
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:227
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip6_xmit+0x79d/0xb50 net/ipv6/ip6_output.c:343
 sctp_v6_xmit+0x413/0x730 net/sctp/ipv6.c:250
 sctp_packet_transmit+0x13aa/0x1480 net/sctp/output.c:653
 sctp_packet_singleton+0x118/0x170 net/sctp/outqueue.c:783
 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline]
 sctp_outq_flush+0x300/0x1920 net/sctp/outqueue.c:1212
 sctp_outq_uncork+0x54/0x60 net/sctp/outqueue.c:764
 sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
 sctp_do_sm+0x2c15/0x2ed0 net/sctp/sm_sideeffect.c:1170
 sctp_primitive_ASSOCIATE+0x6e/0x80 net/sctp/primitive.c:73
 sctp_sendmsg_to_asoc+0x85f/0xb90 net/sctp/socket.c:1835
 sctp_sendmsg+0x1280/0x1840 net/sctp/socket.c:2025
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:827
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 __sys_sendto+0x22d/0x2d0 net/socket.c:2117
 __do_sys_sendto net/socket.c:2129 [inline]
 __se_sys_sendto net/socket.c:2125 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:2125
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x20 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12133 Comm: syz-executor.1 Not tainted 6.2.0-rc6-syzkaller-00011-gc0b67534c95c-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
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syz-executor.1 (12133) used greatest stack depth: 9360 bytes left