syzbot

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BUG: KCSAN: data-race in ____nf_conntrack_find net/netfilter/nf_conntrack_core.c:747 [inline] and __nf_ct_refresh_acct+0xfb/0x1b0
BUG: KCSAN: data-race in __nf_conntrack_find_get+0x284/0x870 net/netfilter/nf_conntrack_core.c:778 and __nf_ct_refresh_acct+0xfb/0x1b0

write to 0xffff88812aea4808 of 4 bytes by task 7225 on cpu 0:
 __nf_ct_refresh_acct+0xfb/0x1b0 net/netfilter/nf_conntrack_core.c:1797
 nf_ct_refresh_acct include/net/netfilter/nf_conntrack.h:201 [inline]
 nf_conntrack_tcp_packet+0xd40/0x3390 net/netfilter/nf_conntrack_proto_tcp.c:1161
 nf_conntrack_handle_packet net/netfilter/nf_conntrack_core.c:1633 [inline]
 nf_conntrack_in+0x410/0xaa0 net/netfilter/nf_conntrack_core.c:1727
 ipv4_conntrack_local+0xbe/0x130 net/netfilter/nf_conntrack_proto.c:200
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x83/0x160 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:260 [inline]
 __ip_local_out+0x1f7/0x2b0 net/ipv4/ip_output.c:114
 ip_local_out+0x31/0x90 net/ipv4/ip_output.c:123
 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x45/0x60 include/net/ip.h:236
 __tcp_transmit_skb+0xdeb/0x1cd0 net/ipv4/tcp_output.c:1158
 __tcp_send_ack+0x246/0x300 net/ipv4/tcp_output.c:3685
 tcp_send_ack+0x34/0x40 net/ipv4/tcp_output.c:3691
 tcp_cleanup_rbuf+0x130/0x360 net/ipv4/tcp.c:1575
 tcp_recvmsg+0x633/0x1a30 net/ipv4/tcp.c:2179

read to 0xffff88812aea4808 of 4 bytes by interrupt on cpu 1:
 ____nf_conntrack_find net/netfilter/nf_conntrack_core.c:747 [inline]
 __nf_conntrack_find_get+0x284/0x870 net/netfilter/nf_conntrack_core.c:778
 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1548 [inline]
 nf_conntrack_in+0x2ef/0xaa0 net/netfilter/nf_conntrack_core.c:1710
 ipv4_conntrack_in+0x27/0x40 net/netfilter/nf_conntrack_proto.c:178
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x83/0x160 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:260 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 ip_rcv+0x12f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208
 napi_skb_finish net/core/dev.c:5671 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
 napi_poll net/core/dev.c:6352 [inline]
 net_rx_action+0x3ae/0xa50 net/core/dev.c:6418
 __do_softirq+0x115/0x33f kernel/softirq.c:292

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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