我昨天问过这个问题，但是由于其上下文，它被标记为重复并被关闭，因为它被认为是一个 X/Y 问题，而我只是对“这怎么可能”这个一般性问题感兴趣，因为我的个人研究（在这个网站以及在互联网上）没有返回任何结果，我想更多地了解如何检测和处理这种特殊问题。
root因此，在没有任何背景信息的情况下，昨天我在我们的一台 Debian 服务器上发现了一些文件，虽然归 所有，但 普通用户可以看到， 却看不到root。
它对这些文件尝试了很多命令，无论我尝试什么，user它都会将这些文件视为常规文件，但root反应就像这些文件根本不存在一样（但无论如何也无法覆盖它们）。这些都是不是点文件。
这些命令的结果如下：
作为user
user@debian:/tmp$ groups
user cdrom floppy audio dip video plugdev netdev
user@debian:/tmp$ pwd
/tmp
user@debian:/tmp$ ls -lai
total 320
1048577 drwxrwxrwt 11 root root 4096 Sep 7 13:04 .
2 drwxr-xr-x 23 root root 4096 Sep 6 17:34 ..
5901230 -rw-r----- 1 root root 0 Sep 7 12:59 invisible_file
<other_files>
user@debian:/tmp$ touch invisible_file
touch: cannot touch 'invisible_file': Permission denied
user@debian:/tmp$ rm invisible_file
rm: remove write-protected regular empty file 'invisible_file'? y
rm: cannot remove 'invisible_file': Operation not permitted
user@debian:/tmp$ stat invisible_file
File: invisible_file
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: 801h/2049d Inode: 5901230 Links: 1
Access: (0640/-rw-r-----) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2021-09-07 12:59:54.859124530 +0200
Modify: 2021-09-07 12:59:54.859124530 +0200
Change: 2021-09-07 13:04:03.063441285 +0200
Birth: -
user@debian:/tmp$ install /dev/null invisible_file
install: cannot remove 'invisible_file': Operation not permitted
user@debian:/tmp$ cat invisible_file
cat: invisible_file: Permission denied
user@debian:/tmp$ find /tmp/ -iname "*invisible_file*"
/tmp/invisible_file
user@debian:/tmp$
作为root
root@debian:/tmp# groups
root
root@debian:/tmp# pwd
/tmp
root@debian:/tmp# ls -lai
total 308
1048577 drwxrwxrwt 11 root root 4096 Sep 7 13:04 .
2 drwxr-xr-x 23 root root 4096 Sep 6 17:34 ..
<other_files>
root@debian:/tmp# touch invisible_file
root@debian:/tmp# ls -lai
total 308
1048577 drwxrwxrwt 11 root root 4096 Sep 7 13:04 .
2 drwxr-xr-x 23 root root 4096 Sep 6 17:34 ..
<other_files>
root@debian:/tmp# rm invisible_file
rm: cannot remove 'invisible_file': No such file or directory
root@debian:/tmp# stat invisible_file
stat: cannot stat 'invisible_file': No such file or directory
root@debian:/tmp# install /dev/null invisible_file
install: cannot create regular file 'invisible_file': No such file or directory
root@debian:/tmp# cat invisible_file
cat: invisible_file: No such file or directory
root@debian:/tmp# find /tmp/ -iname "*invisible_file*"
root@debian:/tmp#
请注意，即使在ls命令中，使用的块总数也不同，差异对应于大小invisible_file。
我能够覆盖文件的唯一方法是创建一个具有另一个名称（甚至其他权限）的文件，并将root其mv覆盖invisible_file，但invisible_file一直被隐藏root。
我的问题是：在 Linux 世界中，如何才能让 root 完全忽略某些常规文件，就好像它们根本不存在一样，就像我的情况一样？我该如何调查此事，使这些文件再次可见，并确保没有其他对 root 不可见的文件？
编辑 ：
这是mount输出，它没有向我显示任何特殊的东西：
root@debian:~# mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=4078644k,nr_inodes=1019661,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,noexec,relatime,size=817960k,mode=755)
/dev/sda1 on / type ext4 (rw,relatime,errors=remount-ro,data=ordered)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,mode=755)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=35,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=9463)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,relatime)
mqueue on /dev/mqueue type mqueue (rw,relatime)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=817956k,mode=700,uid=1000,gid=1000)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,relatime)
输出fsck -nf如下：
root@debian:~# fsck -nf
fsck from util-linux 2.29.2
e2fsck 1.43.4 (31-Jan-2017)
Warning! /dev/sda1 is mounted.
Warning: skipping journal recovery because doing a read-only filesystem check.
Pass 1: Checking inodes, blocks, and sizes
Deleted inode 524799 has zero dtime. Fix? no
Inodes that were part of a corrupted orphan linked list found. Fix? no
Inode 1441794 was part of the orphaned inode list. IGNORED.
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Block bitmap differences: -(11108512--11108538)
Fix? no
Free blocks count wrong (16886612, counted=16857986).
Fix? no
Inode bitmap differences: -524799 -1441794
Fix? no
Free inodes count wrong (5867140, counted=5866555).
Fix? no
/dev/sda1: ********** WARNING: Filesystem still has errors **********
/dev/sda1: 162172/6029312 files (0.3% non-contiguous), 7230636/24117248 blocks
root@Confluence:~#
我终于能够fsck对文件系统进行完整运行。它纠正了上面显示的错误，但无济于事，因为文件仍然不可见。