Fix buffer overrun with enums pointers cast to int64_t* when enum is only 32-bit #1687
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dsnopek
added
cherrypick:4.2
cherrypick:4.3
bug
dsnopek
added
cherrypick:4.2
cherrypick:4.3
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cherrypick:4.2
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dsnopek
approved these changes
Jan 20, 2025
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Cherry-picked for 4.2 in PR #1694 |
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Cherry-picked for 4.3 in PR #1695 |
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This replaces godotengine/godot#101639
Bug description (copied from that issue):
the affected code receives a pointer to an enum as a void pointer, and reinterpret casts it to an int64 pointer, probably because int64 is the size used for variants. But enums are not 64 bit by default, and the majority of enums in the godot codebase use the default size, which is usually int (32 bit on most platforms), and never larger unless absolutely needed, see C++ standard on enum size
Since the code immediately does a truncating C-style cast of this int64 to the enum type, the 4 extra bytes will be discarded immediately and not result in any program logic errors.
I verified my changes by diffing the
gen/directories before and after my changes. As intended, only regular enums are affected, bitfields are already 64 bit and do not require an extra copy.