Add bounds check to source map VLQ decoder shift#8331
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sumleo wants to merge 1 commit intoWebAssembly:mainfrom
Open
Add bounds check to source map VLQ decoder shift#8331sumleo wants to merge 1 commit intoWebAssembly:mainfrom
sumleo wants to merge 1 commit intoWebAssembly:mainfrom
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readBase64VLQ() increments the shift value by 5 for each continuation digit with no upper bound. After 7 continuation digits, shift reaches 35 and 'digit << shift' on a uint32_t is undefined behavior (shifting by an amount >= the type width). Add a bounds check after incrementing shift, throwing a MapParseException for malformed VLQ values.
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Summary
readBase64VLQ()incrementsshiftby 5 for each continuation digit with no upper bound.shiftreaches 35 anddigit << shifton auint32_tis undefined behavior (shifting by >= type width).shift, throwingMapParseExceptionfor malformed VLQ values with too many continuation digits.Test plan