[pschweitzer] 63023: [NTOSKRNL] Fix potential overflows CID #701302 CID #1206856

Author: pschweitzer
Date: Sun Apr 27 18:46:26 2014
New Revision: 63023

URL: http://svn.reactos.org/svn/reactos?rev=63023&view=rev
Log:
[NTOSKRNL]
Fix potential overflows

CID #701302
CID #1206856

Modified:
    trunk/reactos/ntoskrnl/fstub/fstubex.c

Modified: trunk/reactos/ntoskrnl/fstub/fstubex.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/fstub/fstubex.c?r…
==============================================================================
--- trunk/reactos/ntoskrnl/fstub/fstubex.c	[iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/fstub/fstubex.c	[iso-8859-1] Sun Apr 27 18:46:26 2014
@@ -1006,7 +1006,7 @@
         if ((Disk->SectorCount - 1ULL) != EfiHeader->AlternateLBA)
         {
             /* We'll update it. First, count number of sectors needed to store
partitions */
-            SectorsForPartitions = (EfiHeader->NumberOfEntries * PARTITION_ENTRY_SIZE)
/ Disk->SectorSize;
+            SectorsForPartitions = ((ULONGLONG)EfiHeader->NumberOfEntries *
PARTITION_ENTRY_SIZE) / Disk->SectorSize;
             /* Then set first usable LBA: Legacy MBR + GPT header + Partitions entries
*/
             EfiHeader->FirstUsableLBA = SectorsForPartitions + 2;
             /* Then set last usable LBA: Last sector - GPT header - Partitions entries
*/
@@ -1313,7 +1313,7 @@
     }
 
     /* Compute sectors taken by partitions */
-    SectorsForPartitions = ((EFIHeader->NumberOfEntries * PARTITION_ENTRY_SIZE) +
Disk->SectorSize - 1) / Disk->SectorSize;
+    SectorsForPartitions = (((ULONGLONG)EFIHeader->NumberOfEntries *
PARTITION_ENTRY_SIZE) + Disk->SectorSize - 1) / Disk->SectorSize;
     if (PrimaryValid)
     {
         WriteBackup = TRUE;