perf: linear nested [quote] and nested brackets (was O(n^2) DoS) - #261
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Two converter/parser quadratic blowups found by a security audit: - BbcodeToDjot::parseQuotesWithDepth recursed on each closed quote's inner content and used unanchored preg_match per position, so deeply nested [quote] was O(n^2) (~19s for 90KB). Now a single stack-based pass, O(n). - The inline parser ran the char-by-char bracket-depth scan for every even when the text has no link/span trigger (, , ), so a balanced nested run like [[[[x]]]] was O(n^2) (~33s at 20k). parseLink now short-circuits on a memoized trigger-presence check (matching carve-php), O(n). Output unchanged; regression tests added.
Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## master #261 +/- ##
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- Coverage 92.37% 92.36% -0.02%
Complexity 3637 3637
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Files 109 109
Lines 10287 10292 +5
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+ Hits 9503 9506 +3
- Misses 784 786 +2 ☔ View full report in Codecov by Harness. 🚀 New features to boost your workflow:
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Two quadratic blowups found by a security audit:
BbcodeToDjot::parseQuotesWithDepthrecursed on each closed quote's inner content and used an unanchoredpreg_matchper position, so deeply nested[quote]was O(n²) (~19s for 90KB). Now a single stack-based pass, O(n) (~0.05s).[even when the text has no link/span trigger, so a balanced nested run like[[[[x]]]]was O(n²) (~33s at 20k).parseLinknow short-circuits on a memoized trigger-presence check (matching carve-php), O(n) (~0.1s).Output unchanged for well-formed input; regression tests added. Full suite (2699), phpstan, phpcs green.