syzbot

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BUG: KCSAN: data-race in __skb_wait_for_more_packets / unix_release_sock

write to 0xffff88817d54d66a of 1 bytes by task 25212 on cpu 1:
 unix_release_sock+0x29a/0x6e0 net/unix/af_unix.c:548
 unix_release+0x2f/0x50 net/unix/af_unix.c:859
 __sock_release net/socket.c:599 [inline]
 sock_close+0x6c/0x150 net/socket.c:1258
 __fput+0x25b/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0xae/0x130 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:301
 do_syscall_64+0x56/0x90 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88817d54d66a of 1 bytes by task 25218 on cpu 0:
 __skb_wait_for_more_packets+0xdd/0x2e0 net/core/datagram.c:106
 unix_dgram_recvmsg+0x1d2/0x870 net/unix/af_unix.c:2113
 unix_seqpacket_recvmsg+0x5a/0x70 net/unix/af_unix.c:2066
 sock_recvmsg_nosec net/socket.c:888 [inline]
 sock_recvmsg net/socket.c:906 [inline]
 sock_read_iter+0x19e/0x1e0 net/socket.c:979
 call_read_iter include/linux/fs.h:2108 [inline]
 generic_file_splice_read+0x22a/0x310 fs/splice.c:311
 sock_splice_read+0xa5/0xb0 net/socket.c:957
 do_splice_to fs/splice.c:796 [inline]
 splice_file_to_pipe+0x233/0x360 fs/splice.c:1018
 do_splice+0xbc2/0xd30 fs/splice.c:1104
 __do_splice fs/splice.c:1144 [inline]
 __do_sys_splice fs/splice.c:1350 [inline]
 __se_sys_splice+0x2a6/0x390 fs/splice.c:1332
 __x64_sys_splice+0x74/0x80 fs/splice.c:1332
 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: 25218 Comm: syz-executor.0 Not tainted 5.13.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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