[patch 6/6] x86: Add checks for virtual addresses in __phys_addr()
From: Christoph Lameter
Date: Fri May 09 2008 - 22:12:56 EST
Add checks to insure that virtual addresses are not used in invalid contexts.
Signed-off-by: Christoph Lameter <clameter@xxxxxxx>
---
arch/x86/mm/ioremap.c | 15 +++++++--------
include/asm-x86/page_32.h | 7 ++++++-
2 files changed, 13 insertions(+), 9 deletions(-)
Index: linux-2.6/arch/x86/mm/ioremap.c
===================================================================
--- linux-2.6.orig/arch/x86/mm/ioremap.c 2008-05-07 16:27:09.792659191 -0700
+++ linux-2.6/arch/x86/mm/ioremap.c 2008-05-07 19:46:34.733509101 -0700
@@ -21,29 +21,28 @@
#include <asm/pgalloc.h>
#include <asm/pat.h>
-#ifdef CONFIG_X86_64
+#if defined(CONFIG_DEBUG_VM) || defined(CONFIG_X86_64)
unsigned long __phys_addr(unsigned long x)
{
+ VM_BUG_ON(is_vmalloc_addr((void *)x));
+#ifdef CONFIG_X86_64
if (x >= __START_KERNEL_map)
return x - __START_KERNEL_map + phys_base;
+#endif
return x - PAGE_OFFSET;
}
EXPORT_SYMBOL(__phys_addr);
+#endif
static inline int phys_addr_valid(unsigned long addr)
{
+#ifdef CONFIG_X86_64
return addr < (1UL << boot_cpu_data.x86_phys_bits);
-}
-
#else
-
-static inline int phys_addr_valid(unsigned long addr)
-{
return 1;
-}
-
#endif
+}
int page_is_ram(unsigned long pagenr)
{
Index: linux-2.6/include/asm-x86/page_32.h
===================================================================
--- linux-2.6.orig/include/asm-x86/page_32.h 2008-05-07 16:27:12.191419001 -0700
+++ linux-2.6/include/asm-x86/page_32.h 2008-05-07 19:30:46.444980299 -0700
@@ -64,7 +64,12 @@ typedef struct page *pgtable_t;
#endif
#ifndef __ASSEMBLY__
-#define __phys_addr(x) ((x) - PAGE_OFFSET)
+#ifdef CONFIG_DEBUG_VM
+unsigned long __phys_addr(unsigned long x)
+#else
+#define __phys_addr(x) ((x) - PAGE_OFFSET)
+#endif
+
#define __phys_reloc_hide(x) RELOC_HIDE((x), 0)
#ifdef CONFIG_FLATMEM
--
--
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