feat(misconf): Support symlinks inside of tar archives

[simar7]

Discussed in #6554

^{Originally posted by fabpiaf April 24, 2024}

Description

x.tar is a gunzipped docker image.

trivy filesystem --scanners misconfig x.tar
2024-04-24T10:27:06.161Z        INFO    Misconfiguration scanning is enabled
2024-04-24T10:27:06.808Z        FATAL   filesystem scan error: scan error: scan failed: failed analysis: post analysis error: post analysis error: helm scan error: scan config error: walk dir error: failed to add tar "x.tar" to FS: header type '2' is not supported

but:

tar xf x.tar
trivy filesystem --scanners misconfig taredfolder
2024-04-24T10:28:08.086Z        INFO    Misconfiguration scanning is enabled
2024-04-24T10:28:16.060Z        INFO    Detected config files: 16

somename/taredfolder/runtime/templates/deployment.yaml (helm)

Tests: 139 (SUCCESSES: 125, FAILURES: 14, EXCEPTIONS: 0)
Failures: 14 (UNKNOWN: 0, LOW: 9, MEDIUM: 4, HIGH: 1, CRITICAL: 0)

...

Desired Behavior

trivy scans tar successfully without prior manual extraction

Actual Behavior

trivy needs manual extraction prior to scanning

Reproduction Steps

see above

Target

Filesystem

Scanner

Misconfiguration

Output Format

None

Mode

Standalone

Debug Output

2024-04-24T10:32:23.077Z        DEBUG   Severities: ["UNKNOWN" "LOW" "MEDIUM" "HIGH" "CRITICAL"]
2024-04-24T10:32:23.078Z        DEBUG   Ignore statuses {"statuses": null}
2024-04-24T10:32:23.083Z        DEBUG   cache dir:  /home/test/.cache/trivy
2024-04-24T10:32:23.083Z        INFO    Misconfiguration scanning is enabled
2024-04-24T10:32:23.083Z        DEBUG   Policies successfully loaded from disk
2024-04-24T10:32:23.083Z        DEBUG   Enabling misconfiguration scanners: [azure-arm cloudformation dockerfile helm kubernetes terraform terraformplan-json terraformplan-snapshot]
2024-04-24T10:32:23.104Z        DEBUG   Walk the file tree rooted at 'x.tar' in parallel
2024-04-24T10:32:23.104Z        DEBUG   Scanning Helm files for misconfigurations...
2024-04-24T10:32:23.104Z        DEBUG   [misconf] 32:23.104727510 helm.scanner.rego                Overriding filesystem for policies!
2024-04-24T10:32:23.171Z        DEBUG   [misconf] 32:23.171272797 helm.scanner.rego                Loaded 194 policies from disk.
2024-04-24T10:32:23.171Z        DEBUG   [misconf] 32:23.171696638 helm.scanner.rego                Overriding filesystem for data!
2024-04-24T10:32:23.744Z        FATAL   filesystem scan error:
    github.com/aquasecurity/trivy/pkg/commands/artifact.Run
        github.com/aquasecurity/trivy/pkg/commands/artifact/run.go:429
  - scan error:
    github.com/aquasecurity/trivy/pkg/commands/artifact.(*runner).scanArtifact
        github.com/aquasecurity/trivy/pkg/commands/artifact/run.go:269
  - scan failed:
    github.com/aquasecurity/trivy/pkg/commands/artifact.scan
        github.com/aquasecurity/trivy/pkg/commands/artifact/run.go:710
  - failed analysis:
    github.com/aquasecurity/trivy/pkg/scanner.Scanner.ScanArtifact
        github.com/aquasecurity/trivy/pkg/scanner/scan.go:148
  - post analysis error:
    github.com/aquasecurity/trivy/pkg/fanal/artifact/local.Artifact.Inspect
        github.com/aquasecurity/trivy/pkg/fanal/artifact/local/fs.go:164
  - post analysis error:
    github.com/aquasecurity/trivy/pkg/fanal/analyzer.AnalyzerGroup.PostAnalyze
        github.com/aquasecurity/trivy/pkg/fanal/analyzer/analyzer.go:496
  - helm scan error:
    github.com/aquasecurity/trivy/pkg/fanal/analyzer/config.(*Analyzer).PostAnalyze
        github.com/aquasecurity/trivy/pkg/fanal/analyzer/config/config.go:47
  - scan config error:
    github.com/aquasecurity/trivy/pkg/misconf.(*Scanner).Scan
        github.com/aquasecurity/trivy/pkg/misconf/scanner.go:162
  - walk dir error: failed to add tar "x.tar" to FS: header type '2' is not supported

Operating System

archlinux

Version

Version: 0.50.1
Vulnerability DB:
  Version: 2
  UpdatedAt: 2024-04-24 06:10:39.74901266 +0000 UTC
  NextUpdate: 2024-04-24 12:10:39.749012299 +0000 UTC
  DownloadedAt: 2024-04-24 06:16:07.509008473 +0000 UTC
Policy Bundle:
  Digest: sha256:aa1640957b796d93a0ffc5d91237ee6b7ed9467b8f1825279384d29f91b9e590
  DownloadedAt: 2024-04-23 10:57:09.408356928 +0000 UTC

Checklist

• Run trivy image --reset
• Read the troubleshooting