From b9615a08ff1f70d112b480673ebd5079468658a4 Mon Sep 17 00:00:00 2001
From: John Hodge <tpg@mutabah.net>
Date: Thu, 15 Jul 2010 23:03:19 +0800
Subject: [PATCH] Fixing binary loader bugs relating to page sizes

---
 Kernel/bin/elf.c | 17 ++++++++++-------
 Kernel/binary.c  | 31 ++++++++++++++++++++++++++-----
 Kernel/modules.c | 14 --------------
 3 files changed, 36 insertions(+), 26 deletions(-)

diff --git a/Kernel/bin/elf.c b/Kernel/bin/elf.c
index 731d1514..4bf15fa2 100644
--- a/Kernel/bin/elf.c
+++ b/Kernel/bin/elf.c
@@ -2,7 +2,7 @@
  * Acess v0.1
  * ELF Executable Loader Code
  */
-#define DEBUG	0
+#define DEBUG	1
 #include <acess.h>
 #include <binary.h>
 #include "elf.h"
@@ -35,7 +35,7 @@ tBinary *Elf_Load(int fp)
 	 int	iPageCount;
 	 int	count;
 	
-	ENTER("ifp", fp);
+	ENTER("xfp", fp);
 	
 	// Read ELF Header
 	VFS_Read(fp, sizeof(hdr), &hdr);
@@ -126,13 +126,15 @@ tBinary *Elf_Load(int fp)
 		LOG("phtab[%i] = {VAddr:0x%x,Offset:0x%x,FileSize:0x%x}",
 			i, phtab[i].VAddr, phtab[i].Offset, phtab[i].FileSize);
 		
-		if( (phtab[i].FileSize & 0xFFF) < 0x1000 - (phtab[i].VAddr & 0xFFF) )
-			lastSize = phtab[i].FileSize;
-		else
+		//if( (phtab[i].FileSize & 0xFFF) < 0x1000 - (phtab[i].VAddr & 0xFFF) )
+		//	lastSize = phtab[i].FileSize;
+		//else
 			lastSize = (phtab[i].FileSize & 0xFFF) + (phtab[i].VAddr & 0xFFF);
-		lastSize &= 0xFFF;
+		//lastSize &= 0xFFF;
+		
+		//LOG("lastSize = 0x%x", lastSize);
 		
-		LOG("lastSize = 0x%x", lastSize);
+		lastSize = phtab[i].FileSize;
 		
 		// Get Pages
 		count = ( (phtab[i].VAddr&0xFFF) + phtab[i].FileSize + 0xFFF) >> 12;
@@ -152,6 +154,7 @@ tBinary *Elf_Load(int fp)
 				ret->Pages[j+k].Size = 4096;
 			LOG("ret->Pages[%i].Size = 0x%x", j+k, ret->Pages[j+k].Size);
 			ret->Pages[j+k].Flags = 0;
+			lastSize -= ret->Pages[j+k].Size;
 		}
 		count = (phtab[i].MemSize + 0xFFF) >> 12;
 		for(;k<count;k++)
diff --git a/Kernel/binary.c b/Kernel/binary.c
index eb7094d2..72e8210a 100644
--- a/Kernel/binary.c
+++ b/Kernel/binary.c
@@ -10,7 +10,6 @@
 // === CONSTANTS ===
 #define BIN_LOWEST	MM_USER_MIN		// 1MiB
 #define BIN_GRANUALITY	0x10000		// 64KiB
-//! \todo Move 0xBC000000 to mm_virt.h
 #define BIN_HIGHEST	(USER_LIB_MAX-BIN_GRANUALITY)		// Just below the kernel
 #define	KLIB_LOWEST	MM_MODULE_MIN
 #define KLIB_GRANUALITY	0x10000		// 32KiB
@@ -434,7 +433,7 @@ tBinary *Binary_DoLoad(char *truePath)
 	LOG("NumPages: %i", pBinary->NumPages);
 	
 	// Read Data
-	for(i=0;i<pBinary->NumPages;i++)
+	for(i = 0; i < pBinary->NumPages; i ++)
 	{
 		Uint	dest;
 		tPAddr	paddr;
@@ -461,12 +460,34 @@ tBinary *Binary_DoLoad(char *truePath)
 		else
 		{
 			VFS_Seek( fp, pBinary->Pages[i].Physical, 1 );
-			if(pBinary->Pages[i].Size != 0x1000) {
+			// If the address is not aligned, or the page is not full
+			// sized, copy part of it
+			if( (dest & 0xFFF) > 0 || pBinary->Pages[i].Size < 0x1000)
+			{
+				// Validate the size to prevent Kernel page faults
+				// Clips to one page and prints a warning
+				if( pBinary->Pages[i].Size + (dest & 0xFFF) > 0x1000) {
+					Log_Warning("Binary", "Loader error: Page %i (%p) of '%s' is %i bytes (> 4096)",
+						i, pBinary->Pages[i].Virtual, truePath,
+						(dest&0xFFF) + pBinary->Pages[i].Size);
+					pBinary->Pages[i].Size = 0x1000 - (dest & 0xFFF);
+				}		
 				LOG("%i - 0x%llx - 0x%x bytes",
 					i, pBinary->Pages[i].Physical, pBinary->Pages[i].Size);
-				memset( (void*)dest, 0, 0x1000 -(dest&0xFFF) );
+				// Zero from `dest` to the end of the page
+				memset( (void*)dest, 0, 0x1000 - (dest&0xFFF) );
+				// Read in the data
 				VFS_Read( fp, pBinary->Pages[i].Size, (void*)dest );
-			} else {
+			}
+			// Full page
+			else
+			{
+				// Check if the page is oversized
+				if(pBinary->Pages[i].Size > 0x1000)
+					Log_Warning("Binary", "Loader error - Page %i (%p) of '%s' is %i bytes (> 4096)",
+						i, pBinary->Pages[i].Virtual, truePath,
+						pBinary->Pages[i].Size);
+				// Read data
 				LOG("%i - 0x%x", i, pBinary->Pages[i].Physical);
 				VFS_Read( fp, 0x1000, (void*)dest );
 			}
diff --git a/Kernel/modules.c b/Kernel/modules.c
index c9f3a70a..9f6d3c54 100644
--- a/Kernel/modules.c
+++ b/Kernel/modules.c
@@ -349,20 +349,6 @@ int Module_LoadFile(char *Path, char *ArgString)
 		return 0;
 	}
 	
-	// Check magic number
-	if(info->Magic != MODULE_MAGIC)
-	{
-		Log_Warning("Module", "Module's magic value is invalid (0x%x != 0x%x)", info->Magic, MODULE_MAGIC);
-		return 0;
-	}
-	
-	// Check Architecture
-	if(info->Arch != MODULE_ARCH_ID)
-	{
-		Log_Warning("Module", "Module is for a different architecture");
-		return 0;
-	}
-	
 	#if 1
 	if( Module_int_Initialise( info, ArgString ) )
 	{
-- 
2.20.1