PermissionModeWrittenInDecimal

warning native off by default

Group: Probable bugs

A decimal permission literal can represent a different bitmask from the intended octal notation. Write Unix permission masks with an explicit octal prefix. This inspection is disabled by default because the intended policy or use can vary.

Example

<?php
chmod($path,755);
mkdir($path,1777);

Reported:

• line 2: Write the permission mask in octal notation.
• line 3: Write the permission mask in octal notation.

Detection

• Resolved chmod or mkdir mode argument is a decimal integer token of exactly three/four octal digits with nonzero first digit and numeric value exceeding 0777, such as 755. Report disabled-by-default notation hazard; explicit octal, hex, symbolic/bitwise mode excluded.
• Resolve builtin functions, classes, constants and methods; user-defined lookalikes are excluded. Follow only bounded local proof in one lexical scope.
• Emit one finding per violating operation, not per supporting evidence statement. When the proof is inconclusive, nothing is reported.

Exceptions (no report)

• Do not report unresolved or shadowed builtin names, unknown values, or incomplete receiver/type provenance. Unknown calls, aliases escaping, and intervening writes invalidate local proof. Similar code outside the stated detection contract is not a finding.
• Both standard suppression forms suppress this native ID.

Fix

None. Choosing a repair requires intent or additional runtime information.

PHP versions

Available throughout supported PHP 5.3–8.5 where the referenced builtin/extension is available. Respect syntax/version-specific receiver contracts; unavailable APIs are not this rule’s concern.

Configure

In custos.json:

{
  "rules": {
    "PermissionModeWrittenInDecimal": {
      "enabled": true
    }
  }
}

Suppress

Before the statement or declaration (or the first statement of the file):

// @custos-ignore PermissionModeWrittenInDecimal