gh-153981: Fix use after free bug itertools.count()#153983
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gh-153981: Fix use after free bug itertools.count()#153983johng wants to merge 4 commits intopython:mainpython/cpython:mainfrom johng:use-after-free-iter-toolsjohng/cpython:use-after-free-iter-toolsCopy head branch name to clipboard
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Obtain a reference to lz->long_cnt, lz->long_step such that we don't hit a use after free
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This appears to add some very slight overhead to repr in slow mode, no impact to the likely more heavily used fast mode |
picnixz
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Jul 24, 2026
| if (lz->long_cnt == NULL) { | ||
| PyObject *long_cnt, *long_step, *result; | ||
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| Py_BEGIN_CRITICAL_SECTION(lz); |
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I would suggest uaimg PyUnicodeWriter to avoid all those ifs that are a bit unreadable. It is slightly slower but I thimk it is fine.
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Performances are not really inportant for |
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
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Obtain a reference to lz->long_cnt, lz->long_step
such that we don't hit a use after free.