syzbot

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BUG: KCSAN: data-race in close_fd / do_select

write to 0xffff888142517d00 of 8 bytes by task 20462 on cpu 1:
 instrument_write include/linux/instrumented.h:42 [inline]
 __clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:42 [inline]
 __clear_open_fd fs/file.c:254 [inline]
 __put_unused_fd fs/file.c:542 [inline]
 pick_file fs/file.c:612 [inline]
 close_fd+0xe8/0x1e0 fs/file.c:624
 __do_sys_close fs/open.c:1331 [inline]
 __se_sys_close fs/open.c:1329 [inline]
 __x64_sys_close+0x1b/0x70 fs/open.c:1329
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888142517d00 of 8 bytes by task 20472 on cpu 0:
 max_select_fd fs/select.c:446 [inline]
 do_select+0x29d/0xf40 fs/select.c:487
 core_sys_select+0x403/0x690 fs/select.c:677
 kern_select fs/select.c:718 [inline]
 __do_sys_select fs/select.c:725 [inline]
 __se_sys_select+0x17e/0x1c0 fs/select.c:722
 __x64_sys_select+0x63/0x70 fs/select.c:722
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000000000f7 -> 0x0000000000000007

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20472 Comm: syz-executor.0 Not tainted 5.14.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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