kernelbase: Report correct errors in GetModuleHandleExA().

dlls/kernel32/tests/module.c

@@ -953,6 +953,10 @@ static void init_pointers(void)
 
 static void testGetModuleHandleEx(void)
 {
+    static const char longname[] = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+                                   "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+                                   "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+                                   "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
     static const WCHAR kernel32W[] = {'k','e','r','n','e','l','3','2',0};
     static const WCHAR nosuchmodW[] = {'n','o','s','u','c','h','m','o','d',0};
     BOOL ret;
@@ -987,6 +991,20 @@ static void testGetModuleHandleEx(void)
     ok( mod == NULL, "got %p\n", mod );
 
     SetLastError( 0xdeadbeef );
+    ret = GetModuleHandleExA( 0, longname, NULL );
+    error = GetLastError();
+    ok( !ret, "unexpected success\n" );
+    ok( error == ERROR_INVALID_PARAMETER, "got %lu\n", error );
+
+    SetLastError( 0xdeadbeef );
+    mod = (HMODULE)0xdeadbeef;
+    ret = GetModuleHandleExA( 0, longname, &mod );
+    error = GetLastError();
+    ok( !ret, "unexpected success\n" );
+    ok( error == ERROR_MOD_NOT_FOUND, "got %lu\n", error );
+    ok( mod == NULL, "got %p\n", mod );
+
+    SetLastError( 0xdeadbeef );
     ret = GetModuleHandleExW( 0, NULL, NULL );
     error = GetLastError();
     ok( !ret, "unexpected success\n" );

dlls/kernelbase/loader.c

@@ -352,10 +352,21 @@ BOOL WINAPI DECLSPEC_HOTPATCH GetModuleHandleExA( DWORD flags, LPCSTR name, HMOD
 {
     WCHAR *nameW;
 
+    if (!module)
+    {
+        SetLastError( ERROR_INVALID_PARAMETER );
+        return FALSE;
+    }
+
     if (!name || (flags & GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS))
         return GetModuleHandleExW( flags, (LPCWSTR)name, module );
 
-    if (!(nameW = file_name_AtoW( name, FALSE ))) return FALSE;
+    if (!(nameW = file_name_AtoW( name, FALSE )))
+    {
+        *module = NULL;
+        SetLastError( ERROR_MOD_NOT_FOUND );
+        return FALSE;
+    }
     return GetModuleHandleExW( flags, nameW, module );
 }