capng_fill - Linux

Overview

capng_fill is a powerful Linux command that allows users to fill a capability set with capabilities. It is primarily used for managing and manipulating capabilities in Linux systems, enabling fine-grained control over the permissions granted to processes and users.

Syntax

capng_fill [options] [cap1] [cap2] [...]

Options/Flags

• -f: Fill the capability set by matching the specified capabilities to a given file or directory.
• -a: Add the specified capabilities to the existing capability set.
• -r: Remove the specified capabilities from the existing capability set.

Examples

Fill a capability set with specific capabilities:

capng_fill setcap 1 2 3

Add capabilities to an existing set:

capng_fill -a setcap 4

Remove capabilities from an existing set:

capng_fill -r setcap 2 3

Common Issues

• Incorrect capability names: Ensure that the specified capabilities are valid and match the desired functionality.
• Permission denied: Verify that the user has sufficient privileges to modify capabilities.
• Conflicting capabilities: Consider the implications of combining different capabilities and potential conflicts that may arise.

Integration

capng_fill can be combined with other commands like setcap for applying capability sets to processes or files. For example:

setcap $(capng_fill chown,mknod,dac_override) /bin/my_script

Related Commands

• getcap: Get the capabilities associated with a file or process.
• setcap: Set the capabilities of a file or process.
• capabilities(7): Linux man page on Linux capabilities.