syzbot

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BUG: KCSAN: data-race in __skb_wait_for_more_packets / inet_shutdown

write to 0xffff888100c4efaa of 1 bytes by task 7457 on cpu 1:
 inet_shutdown+0x148/0x200 net/ipv4/af_inet.c:891
 __sys_shutdown_sock net/socket.c:2189 [inline]
 __sys_shutdown net/socket.c:2201 [inline]
 __do_sys_shutdown net/socket.c:2209 [inline]
 __se_sys_shutdown+0xf6/0x140 net/socket.c:2207
 __x64_sys_shutdown+0x2d/0x40 net/socket.c:2207
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888100c4efaa of 1 bytes by task 7456 on cpu 0:
 __skb_wait_for_more_packets+0xdd/0x2e0 net/core/datagram.c:106
 __skb_recv_udp+0x761/0x890 net/ipv4/udp.c:1776
 udp_recvmsg+0x155/0xa40 net/ipv4/udp.c:1835
 inet_recvmsg+0xa3/0x200 net/ipv4/af_inet.c:852
 sock_recvmsg_nosec net/socket.c:888 [inline]
 sock_recvmsg net/socket.c:906 [inline]
 __sys_recvfrom+0x1d7/0x2a0 net/socket.c:2034
 __do_sys_recvfrom net/socket.c:2052 [inline]
 __se_sys_recvfrom net/socket.c:2048 [inline]
 __x64_sys_recvfrom+0x74/0x90 net/socket.c:2048
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7456 Comm: syz-executor.5 Not tainted 5.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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