Assume MAX_PATH length for pszDisplayName.

dlls/shell32/brsfolder.c

diff --git a/dlls/shell32/brsfolder.c b/dlls/shell32/brsfolder.c
index 5432bc8..944117f 100644
--- a/dlls/shell32/brsfolder.c
+++ b/dlls/shell32/brsfolder.c
@@ -461,9 +461,9 @@
 	bi.pidlRoot = lpbi->pidlRoot;
 	if (lpbi->pszDisplayName)
 	{
-	  len = MultiByteToWideChar(CP_ACP, 0, lpbi->pszDisplayName, -1, NULL, 0);
-	  bi.pszDisplayName = HeapAlloc(GetProcessHeap(), 0, len * sizeof(WCHAR));
-	  MultiByteToWideChar(CP_ACP, 0, lpbi->pszDisplayName, -1, bi.pszDisplayName, len);
+	  /*lpbi->pszDisplayName is assumed to be MAX_PATH (MSDN) */
+	  bi.pszDisplayName = HeapAlloc(GetProcessHeap(), 0, MAX_PATH * sizeof(WCHAR));
+	  MultiByteToWideChar(CP_ACP, 0, lpbi->pszDisplayName, -1, bi.pszDisplayName, MAX_PATH);
 	}
 	else
 	  bi.pszDisplayName = NULL;