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Why does one command work and the other doesn’t? I have found some remotely related articles, but I failed to understand them.

$ sudo ls -la /tmp/restricted
total 12
drwxr-x---.  2 root root    42 Mar 17 17:40 .
drwxrwxrwt. 12 root root 12288 Mar 17 17:37 ..
-rwxrwxr-x.  1 root tms      0 Mar 17 17:22 foo1
-rwxrwxr-x.  1 root tms      0 Mar 17 17:22 foo2
-rwxrwxr-x.  1 root tms      0 Mar 17 17:22 foo3

$ sudo ls -a /tmp/restricted/foo*
ls: cannot access /tmp/restricted/foo*: No such file or directory

Note that if I change the privileges on /tmp/restricted to 755 instead of 750, both commands succeed:

$ sudo chmod 755 /tmp/restricted/

$ sudo ls -la /tmp/restricted
total 12
drwxr-xr-x.  2 root root    42 Mar 17 17:40 .
drwxrwxrwt. 12 root root 12288 Mar 17 17:37 ..
-rwxrwxr-x.  1 root tms      0 Mar 17 17:22 foo1
-rwxrwxr-x.  1 root tms      0 Mar 17 17:22 foo2
-rwxrwxr-x.  1 root tms      0 Mar 17 17:22 foo3

$ sudo ls -a /tmp/restricted/foo*
/tmp/restricted/foo1  /tmp/restricted/foo2  /tmp/restricted/foo3
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When you run sudo ls -la /tmp/restricted, ls runs as root and has full access to /tmp/restricted.

When you run sudo ls -a /tmp/restricted/foo*, your shell, which is not running as root, attempts to expand /tmp/restricted/foo*. It can’t, and in your case leaves the argument alone. ls runs as root, with an argument of /tmp/restricted/foo*, and since no file exists with that name, fails with the error message you’re seeing.

You can see the same error by forcing your shell not to glob: ls "*" (unless you have a file really named * in the current directory).

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  • @heuvy6 a simple solution would be: sudo sh -c 'ls -a /tmp/restricted/foo*', which will force the * to expand inside root's shell. Commented Mar 19, 2023 at 16:56

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