[3.9] gh-133767: Fix use-after-free in the unicode-escape decoder with an error handler (GH-129648) (GH-133944) #134346
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…er with an error handler (pythonGH-129648) (pythonGH-133944) If the error handler is used, a new bytes object is created to set as the object attribute of UnicodeDecodeError, and that bytes object then replaces the original data. A pointer to the decoded data will became invalid after destroying that temporary bytes object. So we need other way to return the first invalid escape from _PyUnicode_DecodeUnicodeEscapeInternal(). _PyBytes_DecodeEscape() does not have such issue, because it does not use the error handlers registry, but it should be changed for compatibility with _PyUnicode_DecodeUnicodeEscapeInternal(). (cherry picked from commit 9f69a58) (cherry picked from commit 6279eb8) (cherry picked from commit a75953b) (cherry picked from commit 0c33e5b) (cherry picked from commit 8b528ca) Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
freebsd-git
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May 29, 2025
Reference: python/cpython#134346 PR: 287009
mcepl
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May 31, 2025
freebsd-git
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Jun 1, 2025
Reference: python/cpython#134346 PR: 287009 (cherry picked from commit c9ca6e6)
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If the error handler is used, a new bytes object is created to set as the object attribute of UnicodeDecodeError, and that bytes object then replaces the original data. A pointer to the decoded data will became invalid after destroying that temporary bytes object. So we need other way to return the first invalid escape from _PyUnicode_DecodeUnicodeEscapeInternal().
_PyBytes_DecodeEscape() does not have such issue, because it does not use the error handlers registry, but it should be changed for compatibility with _PyUnicode_DecodeUnicodeEscapeInternal().
(cherry picked from commit 9f69a58) (cherry picked from commit 6279eb8) (cherry picked from commit a75953b) (cherry picked from commit 0c33e5b) (cherry picked from commit 8b528ca)
unicode_escapedecoder with error handler #133767