Troubleshooting SAST

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The following troubleshooting scenarios have been collected from customer support cases. If you experience a problem not addressed here, or the information here does not fix your problem, see the GitLab Support page for ways to get help.

Debug-level logging

Debug-level logging can help when troubleshooting. For details, see debug-level logging.

Changes in the CI/CD template

The GitLab-managed SAST CI/CD template controls which analyzer jobs run and how they’re configured. While using the template, you might experience a job failure or other pipeline error. For example, you might:

  • See an error message like '<your job>' needs 'spotbugs-sast' job, but 'spotbugs-sast' is not in any previous stage when you view an affected pipeline.
  • Experience another type of unexpected issue with your CI/CD pipeline configuration.

If you’re experiencing a job failure or seeing a SAST-related yaml invalid pipeline status, you can temporarily revert to an older version of the template so your pipelines keep working while you investigate the issue. To use an older version of the template, change the existing include statement in your CI/CD YAML file to refer to a specific template version, such as v15.3.3-ee: 

include:
  remote: 'https://gitlab.com/gitlab-org/gitlab/-/raw/v15.3.3-ee/lib/gitlab/ci/templates/Jobs/SAST.gitlab-ci.yml'

If your GitLab instance has limited network connectivity, you can also download the file and host it elsewhere.

You should only use this solution temporarily, returning to the standard template as soon as possible.

Errors in a specific analyzer job

GitLab SAST analyzers are released as container images. If you’re seeing a new error that doesn’t appear to be related to the GitLab-managed SAST CI/CD template or changes in your own project, you can try pinning the affected analyzer to a specific older version.

Each analyzer project has a CHANGELOG.md file listing the changes made in each available version.

Job log messages

The SAST job’s log may include error messages that help pinpoint the root cause. Below are some of the error messages and recommended actions.

Executable format 

exec /bin/sh: exec format error` message in job log

GitLab SAST analyzers only support running on the amd64 CPU architecture. This message indicates that the job is being run on a different architecture, such as arm.

Docker error 

Error response from daemon: error processing tar file: docker-tar: relocation error

This error occurs when the Docker version that runs the SAST job is 19.03.0. Consider updating to Docker 19.03.1 or greater. Older versions are not affected. For more details, see issue 13830 - “Current SAST container fails”.

No matching files 

gl-sast-report.json: no matching files

For information on this, see the general Application Security troubleshooting section.

Configuration only 

sast is used for configuration only, and its script should not be executed

For information on this, see the GitLab Secure troubleshooting section.

SAST jobs run unexpectedly

The SAST CI template uses the rules:exists parameter. For performance reasons, a maximum number of 10000 matches are made against the given glob pattern. If the number of matches exceeds the maximum, the rules:exists parameter returns true. Depending on the number of files in your repository, a SAST job might be triggered even if the scanner doesn’t support your project. For more details about this limitation, see the rules:exists documentation.

SpotBugs errors

Below are details of the most common SpotBugs errors that occur, and recommended actions.

UTF-8 unmappable character errors

These errors occur when UTF-8 encoding isn’t enabled on a SpotBugs build and there are UTF-8 characters in the source code. To fix this error, enable UTF-8 for your project’s build tool.

For Gradle builds, add the following to your build.gradle file: 

compileJava.options.encoding = 'UTF-8'
tasks.withType(JavaCompile) {
    options.encoding = 'UTF-8'
}

For Maven builds, add the following to your pom.xml file: 

<properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>

Project couldn’t be built

If your job is failing at the build step with the message “Project couldn’t be built”, it’s most likely because your job is asking SpotBugs to build with a tool that isn’t part of its default tools. For a list of the SpotBugs default tools, see SpotBugs’ asdf dependencies.

The solution is to use pre-compilation. Pre-compilation ensures the images required by SpotBugs are available in the job’s container.

Java out of memory error

When a SAST job is running you might get an error that states java.lang.OutOfMemoryError. This issue occurs when Java has run out of memory.

To try to resolve this issue you can:

  • Choose a lower level of effort.
  • Set the CI/CD variable JAVA_OPTS to replace the default -XX:MaxRAMPercentage=80, e.g. -XX:MaxRAMPercentage=90.
  • Tag a larger runner in your spotbugs-sast job.

Exception analyzing

If your job log contains a message of the form “Exception analyzing … using detector …” followed by a Java stack trace, this is not a failure of the SAST pipeline. SpotBugs has determined that the exception is recoverable, logged it, and resumed analysis.

The first “…” part of the message is the class being analyzed - if it’s not part of your project, you can likely ignore the message and the stack trace that follows.

If, on the other hand, the class being analyzed is part of your project, consider creating an issue with the SpotBugs project on GitHub.

Flawfinder encoding error

This occurs when Flawfinder encounters an invalid UTF-8 character. To fix this, apply their documented advice to your entire repository, or only per job using the before_script feature.

You can configure the before_script section in each .gitlab-ci.yml file, or use a pipeline execution policy action to install the encoder and run the converter command. For example, you can add a before_script section to the flawfinder-sast-0 job generated from the execution policy to convert all files with a .cpp extension.

Example pipeline execution policy YAML 

---
scan_execution_policy:
- name: SAST
  description: 'Run SAST on C++ application'
  enabled: true
  rules:
  - type: pipeline
    branch_type: all
  actions:
  - scan: sast
  - scan: custom
    ci_configuration: |-
      flawfinder-sast-0:
          before_script:
            - pip install cvt2utf
            - cvt2utf convert "$PWD" -i cpp

Semgrep slowness, unexpected results, or other errors

If Semgrep is slow, reports too many false positives or false negatives, crashes, fails, or is otherwise broken, see the Semgrep docs for troubleshooting GitLab SAST.