TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
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BUG: KCSAN: data-race in __xfrm_policy_check / __xfrm_policy_check

write to 0xffff8880b1d6dd08 of 8 bytes by interrupt on cpu 1:
 __xfrm_policy_check+0x3ce/0x13e0 net/xfrm/xfrm_policy.c:3585
 __xfrm_policy_check2 include/net/xfrm.h:1101 [inline]
 xfrm_policy_check include/net/xfrm.h:1106 [inline]
 xfrm6_policy_check include/net/xfrm.h:1116 [inline]
 tcp_v6_rcv+0x1a15/0x1aa0 net/ipv6/tcp_ipv6.c:1582
 ip6_protocol_deliver_rcu+0x22a/0xbe0 net/ipv6/ip6_input.c:409
 ip6_input_finish+0x30/0x50 net/ipv6/ip6_input.c:450
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip6_input+0x177/0x190 net/ipv6/ip6_input.c:459
 dst_input include/net/dst.h:442 [inline]
 ip6_rcv_finish+0x110/0x140 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ipv6_rcv+0x1a1/0x1b0 net/ipv6/ip6_input.c:284
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124
 process_backlog+0x1d3/0x420 net/core/dev.c:5955
 napi_poll net/core/dev.c:6392 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6460
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082
 do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337

write to 0xffff8880b1d6dd08 of 8 bytes by interrupt on cpu 0:
 __xfrm_policy_check+0x3ce/0x13e0 net/xfrm/xfrm_policy.c:3585
 __xfrm_policy_check2 include/net/xfrm.h:1101 [inline]
 xfrm_policy_check include/net/xfrm.h:1106 [inline]
 xfrm6_policy_check include/net/xfrm.h:1116 [inline]
 tcp_v6_rcv+0x1a15/0x1aa0 net/ipv6/tcp_ipv6.c:1582
 ip6_protocol_deliver_rcu+0x22a/0xbe0 net/ipv6/ip6_input.c:409
 ip6_input_finish+0x30/0x50 net/ipv6/ip6_input.c:450
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip6_input+0x177/0x190 net/ipv6/ip6_input.c:459
 dst_input include/net/dst.h:442 [inline]
 ip6_rcv_finish+0x110/0x140 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ipv6_rcv+0x1a1/0x1b0 net/ipv6/ip6_input.c:284
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124
 process_backlog+0x1d3/0x420 net/core/dev.c:5955
 napi_poll net/core/dev.c:6392 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6460
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 26965 Comm: syz-executor.1 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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