[Git][wine/wine][master] 2 commits: win32u: Allocate a separate user buffer when packing a large WM_COPYDATA message for user32.

[Alexandre Julliard (＠julliard)]

Alexandre Julliard pushed to branch master at wine / wine

Commits:
05564eb2 by Zhiyi Zhang at 2025-01-27T14:40:39+01:00
win32u: Allocate a separate user buffer when packing a large WM_COPYDATA message for user32.

Before this patch, WM_COPYDATA message data was packed at the end of the message and then passed
to KeUserModeCallback() to call user mode callbacks. However, WM_COPYDATA can contain a large amount
of data so KeUserModeCallback() can cause stack overflows. Manual tests on Windows show that
WM_COPYDATA messages with data <= 2048 bytes do have their data packed at the end of the message.
But for WM_COPYDATA messages with data > 2048 bytes, KiUserCallbackDispatcher() gets a 120 bytes
packed arguments, which is the same size when packing WM_COPYDATA messages with no data. So for
WM_COPYDATA messages with data > 2048 bytes, the data must be packed differently.

Fix FCSExpress hangs after sending WM_COPYDATA messages.

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c346a814 by Zhiyi Zhang at 2025-01-27T14:40:39+01:00
user32/tests: Add tests for WM_COPYDATA.

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5 changed files:

- dlls/user32/tests/msg.c
- dlls/user32/winproc.c
- dlls/win32u/hook.c
- dlls/win32u/message.c
- dlls/win32u/win32u_private.h

View it on GitLab: https://gitlab.winehq.org/wine/wine/-/compare/790cde06590c68a1684477e1df7b6e...