From a65c22c9c99bb4fb504a0ea0613e1968cbde65e3 Mon Sep 17 00:00:00 2001
From: Rafal Kupiec <belliash@codingworkshop.eu.org>
Date: Sat, 30 Dec 2023 14:36:37 +0100
Subject: [PATCH] Make a copy of modules list, because RtlTokenizeWideString()
 modifies input data

---
 xtldr2/xtldr.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/xtldr2/xtldr.c b/xtldr2/xtldr.c
index 09d786a..be50e7d 100644
--- a/xtldr2/xtldr.c
+++ b/xtldr2/xtldr.c
@@ -113,10 +113,10 @@ BlInvokeBootProtocol(IN PLIST_ENTRY OptionsList)
     PWCHAR ModulesList, ProtocolName;
     PLIST_ENTRY OptionsListEntry;
     PXTBL_CONFIG_ENTRY Option;
+    SIZE_T ModuleListLength;
     EFI_STATUS Status;
 
     /* Set default values */
-    ModulesList = NULL;
     ProtocolName = NULL;
 
     /* Iterate through all options provided by boot menu entry */
@@ -134,8 +134,19 @@ BlInvokeBootProtocol(IN PLIST_ENTRY OptionsList)
         }
         else if(RtlCompareWideStringInsensitive(Option->Name, L"BOOTMODULES", 0) == 0)
         {
-            /* Set protocol name */
-            ModulesList = Option->Value;
+            /* Check a length of modules list */
+            ModuleListLength = RtlWideStringLength(Option->Value, 0);
+
+            Status = BlMemoryAllocatePool(sizeof(PWCHAR) * ModuleListLength, (PVOID *)&ModulesList);
+            if(Status != STATUS_EFI_SUCCESS)
+            {
+                /* Failed to allocate memory, print error message and return status code */
+                BlDebugPrint(L"ERROR: Memory allocation failure (Status Code: 0x%lx)\n");
+                return STATUS_EFI_OUT_OF_RESOURCES;
+            }
+
+            /* Make a copy of modules list */
+            RtlCopyMemory(ModulesList, Option->Value, sizeof(PWCHAR) * ModuleListLength);
         }
 
         /* Move to the next option entry */