diff mbox series

[v7,07/11] powerpc/32: prepare shadow area for KASAN

Message ID bada5c0051f749565d27da9527ce933aa205bf86.1551098214.git.christophe.leroy@c-s.fr (mailing list archive)
State New, archived
Headers show
Series KASAN for powerpc/32 | expand

Commit Message

Christophe Leroy Feb. 25, 2019, 1:48 p.m. UTC 
This patch prepares a shadow area for KASAN.

The shadow area will be at the top of the kernel virtual
memory space above the fixmap area and will occupy one
eighth of the total kernel virtual memory space.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/Kconfig              |  5 +++++
 arch/powerpc/include/asm/fixmap.h |  5 +++++
 arch/powerpc/include/asm/kasan.h  | 17 +++++++++++++++++
 arch/powerpc/mm/mem.c             |  4 ++++
 arch/powerpc/mm/ptdump/ptdump.c   |  8 ++++++++
 5 files changed, 39 insertions(+)

Comments

Daniel Axtens Feb. 26, 2019, 5:12 a.m. UTC | #1 
Christophe Leroy <christophe.leroy@c-s.fr> writes:

> This patch prepares a shadow area for KASAN.
>
> The shadow area will be at the top of the kernel virtual
> memory space above the fixmap area and will occupy one
> eighth of the total kernel virtual memory space.
>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> ---
>  arch/powerpc/Kconfig              |  5 +++++
>  arch/powerpc/include/asm/fixmap.h |  5 +++++
>  arch/powerpc/include/asm/kasan.h  | 17 +++++++++++++++++
>  arch/powerpc/mm/mem.c             |  4 ++++
>  arch/powerpc/mm/ptdump/ptdump.c   |  8 ++++++++
>  5 files changed, 39 insertions(+)
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 652c25260838..f446e016f4a1 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -382,6 +382,11 @@ config PGTABLE_LEVELS
>  	default 3 if PPC_64K_PAGES && !PPC_BOOK3S_64
>  	default 4
>  
> +config KASAN_SHADOW_OFFSET
> +	hex
> +	depends on KASAN
> +	default 0xe0000000
> +

Should this live in Kconfig.debug?

Regards,
Daniel

>  source "arch/powerpc/sysdev/Kconfig"
>  source "arch/powerpc/platforms/Kconfig"
>  
> diff --git a/arch/powerpc/include/asm/fixmap.h b/arch/powerpc/include/asm/fixmap.h
> index b9fbed84ddca..51a1a309c919 100644
> --- a/arch/powerpc/include/asm/fixmap.h
> +++ b/arch/powerpc/include/asm/fixmap.h
> @@ -22,7 +22,12 @@
>  #include <asm/kmap_types.h>
>  #endif
>  
> +#ifdef CONFIG_KASAN
> +#include <asm/kasan.h>
> +#define FIXADDR_TOP	KASAN_SHADOW_START
> +#else
>  #define FIXADDR_TOP	((unsigned long)(-PAGE_SIZE))
> +#endif
>  
>  /*
>   * Here we define all the compile-time 'special' virtual
> diff --git a/arch/powerpc/include/asm/kasan.h b/arch/powerpc/include/asm/kasan.h
> index 2efd0e42cfc9..b554d3bd3e2c 100644
> --- a/arch/powerpc/include/asm/kasan.h
> +++ b/arch/powerpc/include/asm/kasan.h
> @@ -12,4 +12,21 @@
>  #define EXPORT_SYMBOL_KASAN(fn)	EXPORT_SYMBOL(fn)
>  #endif
>  
> +#ifndef __ASSEMBLY__
> +
> +#include <asm/page.h>
> +#include <asm/pgtable-types.h>
> +
> +#define KASAN_SHADOW_SCALE_SHIFT	3
> +
> +#define KASAN_SHADOW_OFFSET	ASM_CONST(CONFIG_KASAN_SHADOW_OFFSET)
> +
> +#define KASAN_SHADOW_START	(KASAN_SHADOW_OFFSET + \
> +				 (PAGE_OFFSET >> KASAN_SHADOW_SCALE_SHIFT))
> +
> +#define KASAN_SHADOW_END	0UL
> +
> +#define KASAN_SHADOW_SIZE	(KASAN_SHADOW_END - KASAN_SHADOW_START)
> +
> +#endif /* __ASSEMBLY */
>  #endif
> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> index f6787f90e158..4e7fa4eb2dd3 100644
> --- a/arch/powerpc/mm/mem.c
> +++ b/arch/powerpc/mm/mem.c
> @@ -309,6 +309,10 @@ void __init mem_init(void)
>  	mem_init_print_info(NULL);
>  #ifdef CONFIG_PPC32
>  	pr_info("Kernel virtual memory layout:\n");
> +#ifdef CONFIG_KASAN
> +	pr_info("  * 0x%08lx..0x%08lx  : kasan shadow mem\n",
> +		KASAN_SHADOW_START, KASAN_SHADOW_END);
> +#endif
>  	pr_info("  * 0x%08lx..0x%08lx  : fixmap\n", FIXADDR_START, FIXADDR_TOP);
>  #ifdef CONFIG_HIGHMEM
>  	pr_info("  * 0x%08lx..0x%08lx  : highmem PTEs\n",
> diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
> index 37138428ab55..812ed680024f 100644
> --- a/arch/powerpc/mm/ptdump/ptdump.c
> +++ b/arch/powerpc/mm/ptdump/ptdump.c
> @@ -101,6 +101,10 @@ static struct addr_marker address_markers[] = {
>  	{ 0,	"Fixmap start" },
>  	{ 0,	"Fixmap end" },
>  #endif
> +#ifdef CONFIG_KASAN
> +	{ 0,	"kasan shadow mem start" },
> +	{ 0,	"kasan shadow mem end" },
> +#endif
>  	{ -1,	NULL },
>  };
>  
> @@ -322,6 +326,10 @@ static void populate_markers(void)
>  #endif
>  	address_markers[i++].start_address = FIXADDR_START;
>  	address_markers[i++].start_address = FIXADDR_TOP;
> +#ifdef CONFIG_KASAN
> +	address_markers[i++].start_address = KASAN_SHADOW_START;
> +	address_markers[i++].start_address = KASAN_SHADOW_END;
> +#endif
>  #endif /* CONFIG_PPC64 */
>  }
>  
> -- 
> 2.13.3
diff mbox series

Patch

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 652c25260838..f446e016f4a1 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -382,6 +382,11 @@  config PGTABLE_LEVELS
 	default 3 if PPC_64K_PAGES && !PPC_BOOK3S_64
 	default 4
 
+config KASAN_SHADOW_OFFSET
+	hex
+	depends on KASAN
+	default 0xe0000000
+
 source "arch/powerpc/sysdev/Kconfig"
 source "arch/powerpc/platforms/Kconfig"
 
diff --git a/arch/powerpc/include/asm/fixmap.h b/arch/powerpc/include/asm/fixmap.h
index b9fbed84ddca..51a1a309c919 100644
--- a/arch/powerpc/include/asm/fixmap.h
+++ b/arch/powerpc/include/asm/fixmap.h
@@ -22,7 +22,12 @@ 
 #include <asm/kmap_types.h>
 #endif
 
+#ifdef CONFIG_KASAN
+#include <asm/kasan.h>
+#define FIXADDR_TOP	KASAN_SHADOW_START
+#else
 #define FIXADDR_TOP	((unsigned long)(-PAGE_SIZE))
+#endif
 
 /*
  * Here we define all the compile-time 'special' virtual
diff --git a/arch/powerpc/include/asm/kasan.h b/arch/powerpc/include/asm/kasan.h
index 2efd0e42cfc9..b554d3bd3e2c 100644
--- a/arch/powerpc/include/asm/kasan.h
+++ b/arch/powerpc/include/asm/kasan.h
@@ -12,4 +12,21 @@ 
 #define EXPORT_SYMBOL_KASAN(fn)	EXPORT_SYMBOL(fn)
 #endif
 
+#ifndef __ASSEMBLY__
+
+#include <asm/page.h>
+#include <asm/pgtable-types.h>
+
+#define KASAN_SHADOW_SCALE_SHIFT	3
+
+#define KASAN_SHADOW_OFFSET	ASM_CONST(CONFIG_KASAN_SHADOW_OFFSET)
+
+#define KASAN_SHADOW_START	(KASAN_SHADOW_OFFSET + \
+				 (PAGE_OFFSET >> KASAN_SHADOW_SCALE_SHIFT))
+
+#define KASAN_SHADOW_END	0UL
+
+#define KASAN_SHADOW_SIZE	(KASAN_SHADOW_END - KASAN_SHADOW_START)
+
+#endif /* __ASSEMBLY */
 #endif
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index f6787f90e158..4e7fa4eb2dd3 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -309,6 +309,10 @@  void __init mem_init(void)
 	mem_init_print_info(NULL);
 #ifdef CONFIG_PPC32
 	pr_info("Kernel virtual memory layout:\n");
+#ifdef CONFIG_KASAN
+	pr_info("  * 0x%08lx..0x%08lx  : kasan shadow mem\n",
+		KASAN_SHADOW_START, KASAN_SHADOW_END);
+#endif
 	pr_info("  * 0x%08lx..0x%08lx  : fixmap\n", FIXADDR_START, FIXADDR_TOP);
 #ifdef CONFIG_HIGHMEM
 	pr_info("  * 0x%08lx..0x%08lx  : highmem PTEs\n",
diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
index 37138428ab55..812ed680024f 100644
--- a/arch/powerpc/mm/ptdump/ptdump.c
+++ b/arch/powerpc/mm/ptdump/ptdump.c
@@ -101,6 +101,10 @@  static struct addr_marker address_markers[] = {
 	{ 0,	"Fixmap start" },
 	{ 0,	"Fixmap end" },
 #endif
+#ifdef CONFIG_KASAN
+	{ 0,	"kasan shadow mem start" },
+	{ 0,	"kasan shadow mem end" },
+#endif
 	{ -1,	NULL },
 };
 
@@ -322,6 +326,10 @@  static void populate_markers(void)
 #endif
 	address_markers[i++].start_address = FIXADDR_START;
 	address_markers[i++].start_address = FIXADDR_TOP;
+#ifdef CONFIG_KASAN
+	address_markers[i++].start_address = KASAN_SHADOW_START;
+	address_markers[i++].start_address = KASAN_SHADOW_END;
+#endif
 #endif /* CONFIG_PPC64 */
 }