[3.13] gh-152682: Fix NULL dereference on OOM in symtable_visit_type_param_bound_or_default (GH-152684) - #152697
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JelleZijlstra merged 2 commits intoJul 6, 2026
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…param_bound_or_default` (pythonGH-152684) In `symtable_visit_type_param_bound_or_default()`, when a reserved name (e.g. `__classdict__`) is used as a type parameter, `PyUnicode_FromFormat()` is called to build the SyntaxError message. If the allocation fails and returns NULL, the subsequent `PyErr_SetObject()` and `Py_DECREF()` calls would dereference NULL, causing a segfault. Fix by returning 0 immediately when `PyUnicode_FromFormat()` returns NULL. This propagates the MemoryError set by `PyUnicode_FromFormat()`. The bug was introduced in pythongh-128632 (commit 891c61c). (cherry picked from commit 10ed03e) Co-authored-by: Petr Vaganov <petrvaganoff@gmail.com>
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Documentation build overview465 files changed · + 1 added · ± 424 modified · - 40 deleted + Added ± Modified
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StanFromIreland
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June 30, 2026 15:08
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Disabling till #152684 (comment) is decided. |
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In symtable_visit_type_param_bound_or_default(), when a reserved name
(e.g. __classdict__) is used as a type parameter, PyUnicode_FromFormat()
is called to build the SyntaxError message. If the allocation fails and
returns NULL, the subsequent PyErr_SetObject() and Py_DECREF() calls
would dereference NULL, causing a segfault.
Fix by returning 0 immediately when PyUnicode_FromFormat() returns NULL.
This propagates the MemoryError set by PyUnicode_FromFormat().
The bug was introduced in gh-128632 (commit 891c61c).
(cherry picked from commit 10ed03e)
Co-authored-by: Petr Vaganov petrvaganoff@gmail.com