Kernel/x86 - mboot: Cleaning up source, added sanity checks

diff --git a/KernelLand/Kernel/arch/x86/mboot.c b/KernelLand/Kernel/arch/x86/mboot.c
index 7403f38..08331a1 100644 (file)
--- a/KernelLand/Kernel/arch/x86/mboot.c
+++ b/KernelLand/Kernel/arch/x86/mboot.c
@@ -13,8 +13,6 @@
 int Multiboot_LoadMemoryMap(tMBoot_Info *MBInfo, tVAddr MapOffset, tPMemMapEnt *Map, const int MapSize, tPAddr KStart, tPAddr KEnd)
 {
         int    nPMemMapEnts = 0;
-       tMBoot_MMapEnt  *ent = (void*)((tVAddr)MBInfo->MMapAddr + MapOffset);
-       tMBoot_MMapEnt  *last = (void*)((tVAddr)ent + MBInfo->MMapLength);
        
        ENTER("pMBInfo pMapOffset pMap iMapSize PKStart PKEnd",
                MBInfo, MapOffset, Map, MapSize, KStart, KEnd);
@@ -22,6 +20,8 @@ int Multiboot_LoadMemoryMap(tMBoot_Info *MBInfo, tVAddr MapOffset, tPMemMapEnt *
        // Check that the memory map is present
        if( MBInfo->Flags & (1 << 6) )
        {
+               tMBoot_MMapEnt  *ent = (void*)((tVAddr)MBInfo->MMapAddr + MapOffset);
+               tMBoot_MMapEnt  *last = (void*)((tVAddr)ent + MBInfo->MMapLength);
                // Build up memory map
                nPMemMapEnts = 0;
                while( ent < last && nPMemMapEnts < MapSize )
@@ -48,10 +48,16 @@ int Multiboot_LoadMemoryMap(tMBoot_Info *MBInfo, tVAddr MapOffset, tPMemMapEnt *
                        nPMemMapEnts ++;
                        ent = (void*)( (tVAddr)ent + ent->Size + 4 );
                }
+               if( ent < last )
+               {
+                       Log_Warning("MBoot", "Memory map has >%i entries, internal version is truncated",
+                               MapSize);
+               }
        }
        else if( MBInfo->Flags & (1 << 0) )
        {
                Log_Warning("MBoot", "No memory map passed, using mem_lower and mem_upper");
+               ASSERT(MapSize >= 2);
                nPMemMapEnts = 2;
                Map[0].Start = 0;
                Map[0].Length = MBInfo->LowMem * 1024;