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BUG: KCSAN: data-race in tcp_space include/net/tcp.h:1373 [inline] and tcp_add_backlog+0x4a0/0xcc0
BUG: KCSAN: data-race in __tcp_select_window+0x6b/0x4d0 net/ipv4/tcp_output.c:2685 and tcp_add_backlog+0x4a0/0xcc0

write to 0xffff8881204be12c of 4 bytes by interrupt on cpu 0:
 sk_add_backlog include/net/sock.h:934 [inline]
 tcp_add_backlog+0x4a0/0xcc0 net/ipv4/tcp_ipv4.c:1737
 tcp_v4_rcv+0x1aba/0x1bf0 net/ipv4/tcp_ipv4.c:1925
 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/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

read to 0xffff8881204be12c of 4 bytes by task 7152 on cpu 1:
 tcp_space include/net/tcp.h:1373 [inline]
 __tcp_select_window+0x6b/0x4d0 net/ipv4/tcp_output.c:2685
 tcp_select_window net/ipv4/tcp_output.c:260 [inline]
 __tcp_transmit_skb+0x679/0x1cd0 net/ipv4/tcp_output.c:1113
 tcp_transmit_skb net/ipv4/tcp_output.c:1174 [inline]
 tcp_write_xmit+0x9f3/0x3080 net/ipv4/tcp_output.c:2429
 __tcp_push_pending_frames+0x7b/0x1d0 net/ipv4/tcp_output.c:2605
 tcp_push+0x1e9/0x3d0 net/ipv4/tcp.c:724
 tcp_sendmsg_locked+0x1d1b/0x1ef0 net/ipv4/tcp.c:1402
 tcp_sendmsg+0x39/0x60 net/ipv4/tcp.c:1433
 inet_sendmsg+0x6d/0x90 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0x9f/0xc0 net/socket.c:657
 sock_write_iter+0x16b/0x210 net/socket.c:989
 call_write_iter include/linux/fs.h:1870 [inline]
 new_sync_write+0x388/0x4a0 fs/read_write.c:483
 __vfs_write+0xb1/0xc0 fs/read_write.c:496
 vfs_write fs/read_write.c:558 [inline]
 vfs_write+0x18a/0x390 fs/read_write.c:542

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7152 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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