Fix: Nested rule parser#1
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Nested at-rules and style rules are parsed by recursive descent with no depth bound, so untrusted input with deep nesting overflows the thread stack and aborts the process. Enforce MAX_NESTING_DEPTH (32) in NestedRuleParser::parse_nested, returning ParserError::MaximumNestingDepth once exceeded (or skipping the rule under error recovery). The limit fits within a 512 KiB stack in release builds; real CSS never nests this deep. This is not a real problem for parcel bundler but may be for using `lightningcss` in other applications like email processing
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Nested at-rules and style rules are parsed by recursive descent with no depth bound, so untrusted input with deep nesting overflows the thread stack and aborts the process. Enforce MAX_NESTING_DEPTH (32) in NestedRuleParser::parse_nested, returning ParserError::MaximumNestingDepth once exceeded (or skipping the rule under error recovery). The limit fits within a 512 KiB stack in release builds; real CSS never nests this deep.
This is not a real problem for parcel bundler but may be for using
lightningcssin other applications like email processing