[PATCH 3/6] user32: Zero initialize DEVMODE before passing it to EnumDisplaySettings().

[Zhiyi Zhang]

EnumDisplaySettings() on Wine does not write beyond the end of DEVMODE because it doesn't use
dmDriverExtra currently, but this implementation detail should not be relied on.

Signed-off-by: Zhiyi Zhang <zzhang(a)codeweavers.com>
---
 dlls/user32/sysparams.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/dlls/user32/sysparams.c b/dlls/user32/sysparams.c
index 79f938a3c20..0c0f8fac5d1 100644
--- a/dlls/user32/sysparams.c
+++ b/dlls/user32/sysparams.c
@@ -3369,6 +3369,7 @@ LONG WINAPI ChangeDisplaySettingsExW( LPCWSTR devname, LPDEVMODEW devmode, HWND
 
     if (def_mode)
     {
+        memset(&dm, 0, sizeof(dm));
         dm.dmSize = sizeof(dm);
         if (!EnumDisplaySettingsExW(devname, ENUM_REGISTRY_SETTINGS, &dm, 0))
         {
@@ -3428,6 +3429,8 @@ BOOL WINAPI EnumDisplaySettingsExA(LPCSTR lpszDeviceName, DWORD iModeNum,
     if (lpszDeviceName) RtlCreateUnicodeStringFromAsciiz(&nameW, lpszDeviceName);
     else nameW.Buffer = NULL;
 
+    memset(&devmodeW, 0, sizeof(devmodeW));
+    devmodeW.dmSize = sizeof(devmodeW);
     ret = EnumDisplaySettingsExW(nameW.Buffer,iModeNum,&devmodeW,dwFlags);
     if (ret)
     {
@@ -4808,6 +4811,7 @@ LONG WINAPI QueryDisplayConfig(UINT32 flags, UINT32 *numpathelements, DISPLAYCON
                                        &type, (BYTE *)device_name, sizeof(device_name), NULL, 0))
             goto done;
 
+        memset(&devmode, 0, sizeof(devmode));
         devmode.dmSize = sizeof(devmode);
         if (!EnumDisplaySettingsW(device_name, ENUM_CURRENT_SETTINGS, &devmode))
             goto done;
-- 
2.25.1

[Marvin]

Hi,

While running your changed tests, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?

Full results can be found at:
https://testbot.winehq.org/JobDetails.pl?Key=76842

Your paranoid android.


=== debiant (32 bit report) ===

user32:
menu.c:2337: Test failed: test 25

=== debiant (32 bit Chinese:China report) ===

user32:
monitor: Timeout

=== debiant (32 bit WoW report) ===

user32:
menu.c:2337: Test failed: test 25

=== debiant (64 bit WoW report) ===

user32:
monitor: Timeout