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BUG: KCSAN: data-race in tcp_disconnect / tcp_poll

write to 0xffff88810e1896ea of 1 bytes by task 18252 on cpu 1:
 tcp_disconnect+0x4a4/0xd40 net/ipv4/tcp.c:2927
 __inet_stream_connect+0x543/0x710 net/ipv4/af_inet.c:713
 tcp_sendmsg_fastopen net/ipv4/tcp.c:1191 [inline]
 tcp_sendmsg_locked+0x2036/0x2130 net/ipv4/tcp.c:1233
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1459
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:817
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0x2a8/0x370 net/socket.c:1975
 __do_sys_sendto net/socket.c:1987 [inline]
 __se_sys_sendto net/socket.c:1983 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:1983
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88810e1896ea of 1 bytes by task 18202 on cpu 0:
 tcp_poll+0x355/0x690 net/ipv4/tcp.c:568
 sock_poll+0x23e/0x260 net/socket.c:1244
 vfs_poll include/linux/poll.h:90 [inline]
 do_select+0x8b1/0xfc0 fs/select.c:534
 core_sys_select+0x408/0x690 fs/select.c:677
 kern_select fs/select.c:718 [inline]
 __do_sys_select fs/select.c:725 [inline]
 __se_sys_select+0x180/0x1c0 fs/select.c:722
 __x64_sys_select+0x63/0x70 fs/select.c:722
 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: 18202 Comm: syz-executor.2 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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