nil-check-after-call.yaml

rules:
  - id: nil-check-after-call
    message: Potential `$FOO` nil dereference when `$BAR` is called
    languages: [go]
    severity: WARNING
    metadata:
      category: security
      cwe: "CWE-253: Incorrect Check of Function Return Value"
      subcategory: [vuln]
      confidence: MEDIUM
      likelihood: MEDIUM
      impact: MEDIUM
      technology: [--no-technology--]
      description: "Possible nil dereferences"
      references:
        - https://blog.trailofbits.com/2019/11/07/attacking-go-vr-ttps/

    patterns:
      - pattern-either:
          - pattern: |
              $FOO.$BAR(...)
              ...
              if $FOO != nil { ... }
          - pattern: |
              $FOO.$BAR(...)
              ...
              if $FOO == nil { ... }
          - pattern: |
              $FUNC(..., $FOO.$BAR(...), ...)
              ...
              if $FOO != nil { ... }
          - pattern: |
              $FUNC(..., $FOO.$BAR(...), ...)
              ...
              if $FOO == nil { ... }
      - pattern-not: |
          $FOO.$BAR(...)
          ...
          $FOO = ...
          ...
          if $FOO != nil { ... }
      - pattern-not: |
          $FOO.$BAR(...)
          ...
          ..., $FOO, ... = ...
          ...
          if $FOO == nil { ... }
      - pattern-not: |
          $FOO.$BAR(...)
          ...
          ..., $FOO, ... = ...
          ...
          if $FOO != nil { ... }
      - pattern-not: |
          $FOO.$BAR(...)
          ...
          $FOO = ...
          ...
          if $FOO == nil { ... }
      - pattern-not: |
          ..., $FOO = $FOO.$BAR(...)
          ...
          if $FOO == nil { ... }
      - pattern-not: |
          ..., $FOO = $FOO.$BAR(...)
          ...
          if $FOO != nil { ... }
      - pattern-not: |
          $FOO = $FOO.$BAR(...)
          ...
          if $FOO == nil { ... }
      - pattern-not: |
          $FOO = $FOO.$BAR(...)
          ...
          if $FOO != nil { ... }