[PATCH 0/1] MR1308: ntdll: Fix incorrectly sized mov in user_mode_callback_return.

[Torge Matthies (＠tmatthies)]

This caused non-interactible windows in my Wine builds, where in win32u `dispatch_win_proc_params` got inlined into `call_window_proc` and this mov overwrote the lower 32 bits of `result`, causing WM_NCHITTEST messages to always return 0 or 0xffffffff00000000 (correct result was -1 in that case).

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/1308

[PATCH 1/1] ntdll: Fix incorrectly sized mov in user_mode_callback_return.

[Torge Matthies]

From: Torge Matthies <tmatthies(a)codeweavers.com>

Signed-off-by: Torge Matthies <tmatthies(a)codeweavers.com>
---
 dlls/ntdll/unix/signal_x86_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/ntdll/unix/signal_x86_64.c b/dlls/ntdll/unix/signal_x86_64.c
index ee34da51654..3c61e0728cb 100644
--- a/dlls/ntdll/unix/signal_x86_64.c
+++ b/dlls/ntdll/unix/signal_x86_64.c
@@ -1647,7 +1647,7 @@ __ASM_GLOBAL_FUNC( user_mode_callback_return,
                    "movq 0x10(%rbp),%rsi\n\t"  /* ret_ptr */
                    "movq 0x18(%rbp),%rdi\n\t"  /* ret_len */
                    "movq %rcx,(%rsi)\n\t"
-                   "movq %rdx,(%rdi)\n\t"
+                   "movl %edx,(%rdi)\n\t"
                    "movdqa -0xe0(%rbp),%xmm15\n\t"
                    "movdqa -0xd0(%rbp),%xmm14\n\t"
                    "movdqa -0xc0(%rbp),%xmm13\n\t"
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/1308

[Martin Storsjö]

Thanks for this fix! I was hunting the same issue on arm64, but this led me directly to the solution (in !1318).

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/1308#note_13855