Rémi Bernon : win32u: Lock display devices mutex in find_adapter.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 59a76b3a868c67c27c777b7bd4be85214612e957
URL:    https://gitlab.winehq.org/wine/wine/-/commit/59a76b3a868c67c27c777b7bd4be852...

Author: Rémi Bernon <rbernon(a)codeweavers.com>
Date:   Wed Sep 14 11:32:30 2022 +0200

win32u: Lock display devices mutex in find_adapter.

---

 dlls/win32u/sysparams.c | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/dlls/win32u/sysparams.c b/dlls/win32u/sysparams.c
index 2927c94f2a7..867332624d1 100644
--- a/dlls/win32u/sysparams.c
+++ b/dlls/win32u/sysparams.c
@@ -2020,12 +2020,15 @@ static struct adapter *find_adapter( UNICODE_STRING *name )
     struct display_device *device;
     struct adapter *adapter;
 
+    if (!lock_display_devices()) return NULL;
+
     if (name && name->Length) device = find_adapter_device_by_name( name );
     else device = find_adapter_device_by_id( 0 ); /* use primary adapter */
 
     if (!device) adapter = NULL;
     else adapter = adapter_acquire( CONTAINING_RECORD( device, struct adapter, dev ) );
 
+    unlock_display_devices();
     return adapter;
 }
 
@@ -2493,10 +2496,7 @@ LONG WINAPI NtUserChangeDisplaySettings( UNICODE_STRING *devname, DEVMODEW *devm
 
     if ((!devname || !devname->Length) && !devmode) return apply_display_settings( NULL, NULL, hwnd, flags, lparam );
 
-    if (!lock_display_devices()) return DISP_CHANGE_FAILED;
-    adapter = find_adapter( devname );
-    unlock_display_devices();
-    if (!adapter) return DISP_CHANGE_BADPARAM;
+    if (!(adapter = find_adapter( devname ))) return DISP_CHANGE_BADPARAM;
 
     if (!adapter_get_full_mode( adapter, devmode, &full_mode )) ret = DISP_CHANGE_BADMODE;
     else if ((flags & CDS_UPDATEREGISTRY) && !adapter_set_registry_settings( adapter, &full_mode )) ret = DISP_CHANGE_NOTUPDATED;
@@ -2552,10 +2552,7 @@ BOOL WINAPI NtUserEnumDisplaySettings( UNICODE_STRING *device, DWORD index, DEVM
 
     TRACE( "device %s, index %#x, devmode %p, flags %#x\n", debugstr_us(device), index, devmode, flags );
 
-    if (!lock_display_devices()) return FALSE;
-    adapter = find_adapter( device );
-    unlock_display_devices();
-    if (!adapter) return FALSE;
+    if (!(adapter = find_adapter( device ))) return FALSE;
 
     lstrcpynW( devmode->dmDeviceName, wine_display_driverW, ARRAY_SIZE(devmode->dmDeviceName) );
     devmode->dmSpecVersion = DM_SPECVERSION;