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[3.15] gh-154318: Guard C recursion when hashing nested tuples and frozendicts (GH-154362) - #160128
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…zendicts (pythonGH-154362) * pythongh-154318: Guard C recursion when hashing nested tuples and frozendicts tuple_hash() and frozendict_hash() fold each contained object's hash into an accumulator with PyObject_Hash() inside an unguarded loop. For a deeply nested tuple or frozendict this recurses back into the same function once per level and overflows the C stack (SIGSEGV / STATUS_STACK_OVERFLOW) instead of raising RecursionError. Wrap both loops in _Py_EnterRecursiveCall() / _Py_LeaveRecursiveCall(), as the sibling comparison and repr paths already do. The guard is placed after the cached-hash early return, so repeated hashing of an already-hashed tuple is unaffected. This also covers types.GenericAlias, whose ga_hash() hashes its __args__ tuple and so crashed through tuple_hash(). (cherry picked from commit 08500b0) Co-authored-by: Jason G <41053218+gianghungtien@users.noreply.github.com>
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tuple_hash() and frozendict_hash() fold each contained object's hash into
an accumulator with PyObject_Hash() inside an unguarded loop. For a deeply
nested tuple or frozendict this recurses back into the same function once
per level and overflows the C stack (SIGSEGV / STATUS_STACK_OVERFLOW)
instead of raising RecursionError.
Wrap both loops in _Py_EnterRecursiveCall() / _Py_LeaveRecursiveCall(), as
the sibling comparison and repr paths already do. The guard is placed after
the cached-hash early return, so repeated hashing of an already-hashed
tuple is unaffected.
This also covers types.GenericAlias, whose ga_hash() hashes its args
tuple and so crashed through tuple_hash().
(cherry picked from commit 08500b0)
Co-authored-by: Jason G 41053218+gianghungtien@users.noreply.github.com