[New-bugs-announce] [issue29190] Avoid possible errors in comparing strings

[Serhiy Storchaka]

New submission from Serhiy Storchaka:

PyUnicode_Compare() and PyUnicode_RichCompare() can raise an exception if one of arguments is not ready unicode object. The result is not always checked for error. Proposed patch gets rid of possible bugs. PyUnicode_Compare() and PyUnicode_RichCompare() in Modules/_pickle.c are replaced with _PyUnicode_EqualToASCIIString() and _PyUnicode_EqualToASCIIId() which never fail. Additional check is added in Modules/_decimal/_decimal.c to ensure that the string which is came from a user code is ready.

All other occurrences of PyUnicode_Compare() seems are called only with ready unicode objects.

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components: Extension Modules
files: unicode_compare.patch
keywords: patch
messages: 284895
nosy: serhiy.storchaka
priority: normal
severity: normal
stage: patch review
status: open
title: Avoid possible errors in comparing strings
type: behavior
versions: Python 3.5, Python 3.6, Python 3.7
Added file: http://bugs.python.org/file46184/unicode_compare.patch

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<http://bugs.python.org/issue29190>
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