syzbot

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BUG: KCSAN: data-race in __skb_wait_for_more_packets / inet_shutdown

write to 0xffff88810087036a of 1 bytes by task 18398 on cpu 0:
 inet_shutdown+0x148/0x200 net/ipv4/af_inet.c:891
 __sys_shutdown_sock net/socket.c:2176 [inline]
 __sys_shutdown net/socket.c:2188 [inline]
 __do_sys_shutdown net/socket.c:2196 [inline]
 __se_sys_shutdown+0xf6/0x140 net/socket.c:2194
 __x64_sys_shutdown+0x2d/0x40 net/socket.c:2194
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88810087036a of 1 bytes by task 18397 on cpu 1:
 __skb_wait_for_more_packets+0xe7/0x2f0 net/core/datagram.c:106
 __skb_recv_udp+0x771/0x8a0 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:2021
 __do_sys_recvfrom net/socket.c:2039 [inline]
 __se_sys_recvfrom net/socket.c:2035 [inline]
 __x64_sys_recvfrom+0x74/0x90 net/socket.c:2035
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18397 Comm: syz-executor.3 Not tainted 5.13.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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