Fix a stack corruption issue in CFRegularExpression (SR-1003) #301
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The function _CFRegularExpressionEnumerateMatchesInString() walks the text searching for occurrences of the pattern. For every occurrence, it populates a CFRange array. If the number of capture groups is not greater than 7, it uses an array on the stack (instead of mallocing one). However, the total number of CFRanges inserted is (number of capture groups + 1). The last insert can corrupt the stack if the number of capture groups is 7.
atrick
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Jan 12, 2021
[gardening] Fix warning about strerror return value
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This is the proposed fix for https://bugs.swift.org/browse/SR-1003
The function _CFRegularExpressionEnumerateMatchesInString() walks the text
searching for occurrences of the pattern. For every occurrence, it populates
a CFRange array. If the number of capture groups is not greater than 7, it
uses an array on the stack (instead of mallocing one). However, the total
number of CFRanges inserted is (number of capture groups + 1). The last
insert can corrupt the stack if the number of capture groups is 7 and change the
values of other locals leading to unexplained behaviour.