[PATCH v2] ntdll: Enable WoW64 filesystem redirection when loading libraries.

[Brendan Shanks]

This matches the behavior seen on Windows 7/2008R2 and newer.
Fixes Rockstar Games Launcher installer crashing.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=47912
Signed-off-by: Brendan Shanks 
---
v2: Move enabling below the STATUS_NO_MEMORY early return

dlls/kernel32/tests/loader.c | 2 +-
 dlls/ntdll/loader.c          | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/dlls/kernel32/tests/loader.c b/dlls/kernel32/tests/loader.c
index e5b8c3b28e..912e8600dd 100644
--- a/dlls/kernel32/tests/loader.c
+++ b/dlls/kernel32/tests/loader.c
@@ -3822,7 +3822,7 @@ static void test_wow64_redirection_for_dll(const char *libname)
     if (!GetModuleHandleA(libname))
     {
         lib = LoadLibraryExA(libname, NULL, 0);
-        todo_wine ok (broken(lib == NULL) /* Vista/2008 */ ||
+        ok (broken(lib == NULL) /* Vista/2008 */ ||
             lib != NULL, "Loading %s should succeed with WOW64 redirection disabled\n", libname);
         if (lib)
         {
diff --git a/dlls/ntdll/loader.c b/dlls/ntdll/loader.c
index 2bae3c7bd5..fa1eab4b8b 100644
--- a/dlls/ntdll/loader.c
+++ b/dlls/ntdll/loader.c
@@ -2881,6 +2881,7 @@ static NTSTATUS find_dll_file( const WCHAR *load_path, const WCHAR *libname,
 {
     WCHAR *ext, *dllname;
     NTSTATUS status;
+    ULONG wow64_old_value = 0;

/* first append .dll if needed */

@@ -2897,6 +2898,12 @@ static NTSTATUS find_dll_file( const WCHAR *load_path, const WCHAR *libname,
         libname = dllname;
     }

+    /* Win 7/2008R2 and up seem to re-enable WoW64 FS redirection when loading libraries.
+     * Enable redirection here, and if it was disabled, disable it before returning.
+     */
+    if (is_wow64)
+        RtlWow64EnableFsRedirectionEx(0, &wow64_old_value);
+
     nt_name->Buffer = NULL;

if (!contains_path( libname ))
@@ -2930,6 +2937,8 @@ static NTSTATUS find_dll_file( const WCHAR *load_path, const WCHAR *libname,

done:
     RtlFreeHeap( GetProcessHeap(), 0, dllname );
+    if (is_wow64 && wow64_old_value == 1)
+        RtlWow64EnableFsRedirectionEx(1, &wow64_old_value);
     return status;
 }