bd-kernel-vulns 1.0.4

bd_kernel_vulns - Script to process the Linux Kernel in a BD project to assess vulns applicability based on supplied list of kernel source files (or folders)

Black Duck SCA Kernel Vuln Processor - bd_kernel_vulns.py v1.0.4

PROVISION OF THIS SCRIPT

This script is provided under the MIT license (see LICENSE file).

It does not represent any extension of licensed functionality of Black Duck Software itself and is provided as-is, without warranty or liability.

If you have comments or issues, please raise a GitHub issue here. Black Duck support is not able to respond to support tickets for this OSS utility. Users of this pilot project commit to engage properly with the authors to address any identified issues.

INTRODUCTION

OVERVIEW OF BD_KERNEL_VULNS

This utility accepts a file containing compiled kernel source files (or folders) to filter the vulnerabilities associated with the Linux Kernel component in a Black Duck SCA project version.

Vulnerabilities which reference a kernel source file, but which do not match against the files/folders in the supplied kernel source file will be marked as remediated.

INSTALLATION

1. Create virtualenv
2. Run pip3 install bd_kernel_vulns --upgrade

Alternatively, if you want to build and install the utility locally:

1. clone the repository
2. Create virtualenv
3. Build the utility python3 -m build
4. Install the package pip3 install dist/bd_kernel_vulns-1.0.X-py3-none-any.whl --upgrade

Alternatively, clone the repository locally:

1. Clone the repository
2. Ensure prerequisite packages are installed (see list in pyproject.toml)

PREREQUISITES

1. Black Duck SCA server 2024.1 or newer
2. Black Duck SCA API with either Global Project Manager roles or Project BOM Manager roles for an existing project
3. Python 3.10 or newer

HOW TO RUN

If you installed the utility as a package:

1. Invoke virtualenv where utility was installed
2. Run bd-kernel-vulns OPTIONS

Alternatively, if you have cloned the repository locally:

1. Invoke virtualenv where dependency packages were installed
2. Run python3 PATH_TO_REPOSITORY/run.py OPTIONS

COMMAND LINE OPTIONS

  usage: bd-kernel-vulns [-h] [--blackduck_url BLACKDUCK_URL] [--blackduck_api_token BLACKDUCK_API_TOKEN] [--blackduck_trust_cert] [-p PROJECT] [-v VERSION] <OTHER OPTIONS>

  Mark kernel vulns which are not within a custom kernel as remediated   
  
 -h, --help            show this help message and exit

REQUIRED:
 --blackduck_url BLACKDUCK_URL
        Black Duck server URL (REQUIRED - will also use BLACKDUCK_URL env var)
 --blackduck_api_token BLACKDUCK_API_TOKEN
        Black Duck API token (REQUIRED - will also use BLACKDUCK_API_TOKEN env var)
 -p PROJECT, --project PROJECT 
        Black Duck project to create (REQUIRED)
 -v VERSION, --version VERSION
        Black Duck project version to create (REQUIRED)
-k KERNEL_SOURCE_FILE, --kernel_source_file KERNEL_SOURCE_FILE
        File containing list of source files (or folders) within the kernel (one per line).

OPTIONAL:
 --blackduck_trust_cert
        Black Duck trust server cert (can use BLACKDUCK_TRUST_CERT env var)
 --folders
        Supplied list is kernel source folders (not source files)
 --kernel_comp_name
        Alternate kernel component name (default 'Linux Kernel')
 --remediation_status
        Vulnerability Remediation Status to apply - Default NOT_AFFECTED
        (Options REMEDIATION_COMPLETE, NOT_AFFECTED, MITIGATED, DUPLICATE, IGNORED, 
        PATCHED, NEW, UNDER_INVESTIGATION, NEEDS_REVIEW, AFFECTED, REMEDIATION_REQUIRED)  
 --remediation_justification
        Vulnerability Remediation Justification - Default NO_CODE
        (Options NO_COMPONENT, NO_CODE, NOT_CONTROLLED, NOT_EXECUTED,
        ALREADY_MITIGATED, MITIGATION, NO_FIX_PLANNED,
        NONE_AVAILABLE, VENDOR_FIX, WORKAROUND - only applied if NOT_AFFECTED 
        or AFFECTED selected for remediation status
 --source_file_names_only
        Match only source file names from vulnerabilities against the supplied source file list
        (default is to match full folder names for example 'scripts/mod/file2alias.c' - use with caution
        as can match vulnerabilities by the same kernel source name in different modules)

REMEDIATION STATUS

The utility applies the default remediation status NOT_AFFECTED (with justification NO_CODE) which is a new remediation status available since 2025.1.0. The script identifies the Black Duck server version and modifies the remediation status to 'IGNORED' for versions prior to 2025.1.0 automatically.

KERNEL SOURCE FILES

The utility requires a list of kernel source files in a supplied file. The source file list should include the path of each source file ending in the correct extension for example 'scripts/mod/file2alias.c'. Folder separators should use forward slash '/'. Use the option --source_file_names_only to only match the source file name ignoring folders.

KERNEL SOURCE FOLDERS

If the --folders option is specified, then a list of kernel source file folders is expected in the kernel_source_file, and kernel source files referenced in vulnerabilities will be matched based on the folders where they exist only. For example the file 'scripts/mod/file2alias.c' will match the folder 'scripts', 'mod' or 'scripts/mod'. Leading and trailing '/' separators are not required.

OBTAINING KERNEL SOURCE FILES

FROM RUNNING LINUX IMAGE

The lsmod and modinfo commands can be used to report the compiled objects in the running kernel.

An example bash script to produce the list of kernel source files is shown below:

lsmod | while read module otherfields
do
    modinfo $module | grep '^filename:' | sed -e 's/filename:  *//g' -e 's/\.ko\.zst//g'
done > kfiles.lst

FROM YOCTO BUILD

The bd_scan_yocto_via_sbom utility is recommended to scan Yocto projects, and the --process_kernel_vulns option will call this utility to filter kernel vulnerabilities.

However, if not using this script then processing the module image archive can generate the list of compiled source files as follows:

1. Locate the modules image archive file for the specific build (usually beneath the poky/build/tmp/deploy/images folder - for example modules--6.12.31+git0+f2f3b6cbd9_fee8195f84-r0-qemux86-64-20250608200614.tgz)
2. Extract the list of modules from the file using tar tf FILE | grep '.ko$' | sed -e 's/\.ko$/.c/g' > kfiles.lst

FROM BUILDROOT BUILD

1. Locate the Kernel Build Directory - for example <buildroot_root_directory>/output/build/linux-<kernel_version>/
2. Identify Compiled Object Files (.o files) by running find <buildroot_root_directory>/output/build/linux-<kernel_version>/ -name "*.o" | sed -e 's/\.o$/.c/g' > kfiles.lst