[3.10] gh-149079: Fix O(n^2) canonical ordering in unicodedata.normalize() (GH-149080) (GH-150843) - #155159
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…normalize() (pythonGH-149080) (pythonGH-150843) Replace the insertion sort used for canonical ordering of combining characters with a hybrid approach: insertion sort for short runs (< 20) and counting sort for longer runs, reducing worst-case complexity from O(n^2) to O(n). This prevents denial of service via crafted Unicode strings with many combining characters in alternating CCC order. (cherry picked from commit 991224b) (cherry picked from commit d3ab945) Co-authored-by: Petr Viktorin <[email protected]> Co-authored-by: Seth Larson <[email protected]> Co-authored-by: ch4n3-yoon <[email protected]> Co-authored-by: Seokchan Yoon <[email protected]> Co-authored-by: Stan Ulbrych <[email protected]> Co-authored-by: Bénédikt Tran <[email protected]> Co-authored-by: Serhiy Storchaka <[email protected]> Co-authored-by: Maurycy Pawłowski-Wieroński <[email protected]>
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Replace the insertion sort used for canonical ordering of combining
characters with a hybrid approach: insertion sort for short runs (< 20)
and counting sort for longer runs, reducing worst-case complexity from
O(n^2) to O(n). This prevents denial of service via crafted Unicode
strings with many combining characters in alternating CCC order.
(cherry picked from commit 991224b)
(cherry picked from commit d3ab945)
Co-authored-by: Petr Viktorin [email protected]
Co-authored-by: Seth Larson [email protected]
Co-authored-by: ch4n3-yoon [email protected]
Co-authored-by: Seokchan Yoon [email protected]
Co-authored-by: Stan Ulbrych [email protected]
Co-authored-by: Bénédikt Tran [email protected]
Co-authored-by: Serhiy Storchaka [email protected]
Co-authored-by: Maurycy Pawłowski-Wieroński [email protected]
unicodedata.normalize("NFC")canonical ordering #149079