我一直在尝试创建自定义 ISO 映像，并且取得了成功。然而，在此过程中我遇到了一种我无法理解的情况。
我的系统是 Ubuntu 20.04.6 LTS 桌面。
基本上，当我运行sudo unsquashfs ubuntu-server-minimal.squashfs到一个目录，然后列出父目录的内容时，结果squashfs-根目录目录下，我收到以下信息以及一些警告：
$ ls -l
total 2231416
dr-xr-xr-x 9 mike mike 4096 Aug 9 22:06 extracted-iso
drwxr-xr-x 18 root root 4096 Aug 9 17:20 squashfs-root
-rw-rw-r-- 1 mike mike 2133391360 Sep 18 18:13 ubuntu-22.04.3-live-server-amd64.iso
-r--r--r-- 1 mike mike 151560192 Sep 18 18:15 ubuntu-server-minimal.squashfs
warning: could not open directory 'iso/squashfs-root/var/lib/polkit-1/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/apt/lists/partial/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/snapd/void/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/log/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/pollinate/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/ldconfig/': Permission denied
warning: could not open directory 'iso/squashfs-root/root/': Permission denied
warning: could not open directory 'iso/squashfs-root/run/lock/lvm/': Permission denied
warning: could not open directory 'iso/squashfs-root/run/lvm/': Permission denied
warning: could not open directory 'iso/squashfs-root/etc/polkit-1/localauthority/': Permission denied
warning: could not open directory 'iso/squashfs-root/etc/ssl/private/': Permission denied
这就是我感到困惑的地方。我知道squashfs-根目录归 root 所有，但每个人都有读取权限。其次，在创建chroot进入所需的各种挂载后，警告数量会增加squashfs-根目录例如以下内容：
mount --bind /etc/resolv.conf squashfs-root/etc/resolv.conf
mount -t proc none squashfs-root/proc
mount -t sysfs none squashfs-root/sys
mount -t devpts none squashfs-root/dev/pts
此外，这些警告现在会出现在任何命令中，例如lsb_release -a和pwd：
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.6 LTS
Release: 20.04
Codename: focal
warning: could not open directory 'iso/squashfs-root/var/lib/polkit-1/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/apt/lists/partial/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/snapd/void/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/log/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/pollinate/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/ldconfig/': Permission denied
warning: could not open directory 'iso/squashfs-root/root/': Permission denied
warning: could not open directory 'iso/squashfs-root/run/lock/lvm/': Permission denied
warning: could not open directory 'iso/squashfs-root/run/lvm/': Permission denied
warning: could not open directory 'iso/squashfs-root/etc/polkit-1/localauthority/': Permission denied
warning: could not open directory 'iso/squashfs-root/etc/ssl/private/': Permission denied
$ pwd
/home/mike/custom-iso/iso
warning: could not open directory 'iso/squashfs-root/var/lib/polkit-1/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/apt/lists/partial/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/lib/snapd/void/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/log/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/private/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/pollinate/': Permission denied
warning: could not open directory 'iso/squashfs-root/var/cache/ldconfig/': Permission denied
warning: could not open directory 'iso/squashfs-root/root/': Permission denied
warning: could not open directory 'iso/squashfs-root/run/lock/lvm/': Permission denied
warning: could not open directory 'iso/squashfs-root/run/lvm/': Permission denied
warning: could not open directory 'iso/squashfs-root/etc/polkit-1/localauthority/': Permission denied
warning: could not open directory 'iso/squashfs-root/etc/ssl/private/': Permission denied
- 如果我
sudo su，所有警告都会消失。 - 删除后squashfs-根目录使用 后
sudo rm -fr squashfs-root，所有警告都会消失。
那么这是怎么回事？为什么我会收到这些警告？如何才能抑制这些警告？我是不是做错了什么unsquashfs？
更新：
作为测试，我在 VirtualBox 中创建了两个虚拟机，一个装有 Ubuntu 20.04.6 LTS 桌面，另一个装有 22.04.3 LTS 桌面。我下载了相同的 ISO，提取并像之前一样将 squashfs 解压到两个系统中。我在两个虚拟机中都没有收到任何警告。
因此，看来我当前的系统出了问题，我需要帮助进行故障排除。有什么想法可以开始吗？
答案1
我解决了这个问题。
我意识到的父目录iso/squashfs-root中有一个 Git 存储库，但iso/squashfs-root尚未添加到.gitignore文件。结果，警告实际上来自 Git，而不是操作系统。所以我只是将此目录添加到.gitignore警告就消失了。