[Git][wine/wine][master] windowscodecs: Fix potential integer overflow in PNG format reader.

[Alexandre Julliard (＠julliard)]

Alexandre Julliard pushed to branch master at wine / wine

Commits:
762a9718 by Wei Xie at 2025-11-03T23:18:15+01:00
windowscodecs: Fix potential integer overflow in PNG format reader.

Fixed a potential integer overflow issue in the read_ulong_be function
by adding an explicit cast to ULONG before bit shifting. The data[0]
byte was being shifted left 24 bits without proper casting, which could
cause overflow when the byte value is large and the compiler treats it
as a signed char. This ensures proper 32-bit unsigned integer behavior
during the bitwise OR operations.

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1 changed file:

- dlls/windowscodecs/pngformat.c

View it on GitLab: https://gitlab.winehq.org/wine/wine/-/commit/762a97189f62468360cef07f360bdd6...