capng_updatev - Linux
Overview
capng_updatev modifies the capabilities for a specified process or files. It’s primarily used to adjust access privileges or enhance security by modifying the capability bounding set associated with entities.
Syntax
capng_updatev -c <capability>... [-p] pid | -e executable [-E <context>] [-t type]...
Options
-c <capability>
: Capability(ies) to add or remove. Prefix with+
or-
to indicate action.-p <pid>
: Process ID of the target process.-e <executable>
: Executable file to modify.-E <context>
: Execution context:task
,ambient
, orcurrent
(default:task
).-t <type>
: Type of capabilities to modify:ambient
,effective
,inheritable
, orpermitted
.
Examples
Add Capability to Process
capng_updatev -c +CAP_NET_ADMIN -p 1234
Remove Capability from File
capng_updatev -c -CAP_CHOWN -e /path/to/file
Modify Capabilities in Ambient Context
capng_updatev -c +CAP_USB -E ambient -e /usr/bin/program
Common Issues
- Permission Denied: Ensure you have sufficient privileges to modify capabilities.
- Capability Not Supported: Check if the specified capability is supported by the kernel.
- File Not Found: Verify that the executable or file exists.
Integration
- BPF: Use capng_updatev in BPF programs to dynamically adjust capabilities for security hardening.
- Sandboxing: In conjunction with tools like seccomp, capng_updatev can create restricted environments by limiting capabilities.
Related Commands
- getcap, setcap
- Capabilities in Linux