From 857dd4ae36a55f8dcf122d904ee6993199909d8a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Gardou?= <jerome.gardou@reactos.org>
Date: Mon, 7 Dec 2020 10:22:28 +0100
Subject: [PATCH] [NTOS:MM] Properly handle the 1-offset of paging files

---
 ntoskrnl/mm/pagefile.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/ntoskrnl/mm/pagefile.c b/ntoskrnl/mm/pagefile.c
index b7d8c83e54e..37870520998 100644
--- a/ntoskrnl/mm/pagefile.c
+++ b/ntoskrnl/mm/pagefile.c
@@ -189,7 +189,7 @@ NTSTATUS
 NTAPI
 MmReadFromSwapPage(SWAPENTRY SwapEntry, PFN_NUMBER Page)
 {
-    return MiReadPageFile(Page, FILE_FROM_ENTRY(SwapEntry), OFFSET_FROM_ENTRY(SwapEntry) - 1);
+    return MiReadPageFile(Page, FILE_FROM_ENTRY(SwapEntry), OFFSET_FROM_ENTRY(SwapEntry));
 }
 
 NTSTATUS
@@ -215,6 +215,9 @@ MiReadPageFile(
         return(STATUS_UNSUCCESSFUL);
     }
 
+    /* Normalize offset. */
+    PageFileOffset--;
+
     ASSERT(PageFileIndex < MAX_PAGING_FILES);
 
     PagingFile = MmPagingFile[PageFileIndex];