Linux Permissions 4

Question 1

What is the default umask for a regular (non-root) user on most Linux systems?

Accepted Answer

022

Answer

A umask of 022 is the most common default for regular users, resulting in 644 for files and 755 for directories.

Question 2

Which command grants user 'carol' read and write ACL permissions on report.txt?

Accepted Answer

setfacl -m u:carol:rw report.txt

Answer

The `setfacl -m u:carol:rw` command modifies the ACL to add or update the named user entry with read and write permissions.

Question 3

If a file has permissions rwSr--r--, what does the uppercase 'S' indicate?

Accepted Answer

The setuid bit is set but the owner execute bit is not set

Answer

An uppercase 'S' in the setuid position means the setuid bit is set but the owner does not have execute permission, making it a non-functional setuid.

Question 4

What is the minimum permission a user needs on a directory to create a file inside it?

Accepted Answer

Write and execute permissions on the directory

Answer

Creating a file in a directory requires both write (to add the directory entry) and execute (to traverse the directory) permissions.

Question 5

How do you remove all ACL entries from a file and revert to standard permissions?

Accepted Answer

setfacl -b file.txt

Answer

The `setfacl -b` option removes all extended ACL entries, leaving only the base owner/group/other permissions.

Linux Practice Test

Linux Practice Test

Linux Permissions 4