[PATCH v4 19/39] kasan: rename SHADOW layout macros to META

From: Andrey Konovalov
Date: Thu Oct 01 2020 - 19:11:43 EST


This is a preparatory commit for the upcoming addition of a new hardware
tag-based (MTE-based) KASAN mode.

Hardware tag-based KASAN won't be using shadow memory, but will reuse
these macros. Rename "SHADOW" to implementation-neutral "META".

No functional changes.

Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Reviewed-by: Marco Elver <elver@xxxxxxxxxx>
---
Change-Id: Id2d836bf43b401bce1221cc06e745185f17b1cc
---
mm/kasan/report.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 67aa30b45805..13b27675a696 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -31,11 +31,11 @@
#include "kasan.h"
#include "../slab.h"

-/* Shadow layout customization. */
-#define SHADOW_BYTES_PER_BLOCK 1
-#define SHADOW_BLOCKS_PER_ROW 16
-#define SHADOW_BYTES_PER_ROW (SHADOW_BLOCKS_PER_ROW * SHADOW_BYTES_PER_BLOCK)
-#define SHADOW_ROWS_AROUND_ADDR 2
+/* Metadata layout customization. */
+#define META_BYTES_PER_BLOCK 1
+#define META_BLOCKS_PER_ROW 16
+#define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK)
+#define META_ROWS_AROUND_ADDR 2

static unsigned long kasan_flags;

@@ -238,7 +238,7 @@ static void print_address_description(void *addr, u8 tag)

static bool row_is_guilty(const void *row, const void *guilty)
{
- return (row <= guilty) && (guilty < row + SHADOW_BYTES_PER_ROW);
+ return (row <= guilty) && (guilty < row + META_BYTES_PER_ROW);
}

static int shadow_pointer_offset(const void *row, const void *shadow)
@@ -247,7 +247,7 @@ static int shadow_pointer_offset(const void *row, const void *shadow)
* 3 + (BITS_PER_LONG/8)*2 chars.
*/
return 3 + (BITS_PER_LONG/8)*2 + (shadow - row)*2 +
- (shadow - row) / SHADOW_BYTES_PER_BLOCK + 1;
+ (shadow - row) / META_BYTES_PER_BLOCK + 1;
}

static void print_memory_metadata(const void *addr)
@@ -257,15 +257,15 @@ static void print_memory_metadata(const void *addr)
const void *shadow_row;

shadow_row = (void *)round_down((unsigned long)shadow,
- SHADOW_BYTES_PER_ROW)
- - SHADOW_ROWS_AROUND_ADDR * SHADOW_BYTES_PER_ROW;
+ META_BYTES_PER_ROW)
+ - META_ROWS_AROUND_ADDR * META_BYTES_PER_ROW;

pr_err("Memory state around the buggy address:\n");

- for (i = -SHADOW_ROWS_AROUND_ADDR; i <= SHADOW_ROWS_AROUND_ADDR; i++) {
+ for (i = -META_ROWS_AROUND_ADDR; i <= META_ROWS_AROUND_ADDR; i++) {
const void *kaddr = kasan_shadow_to_mem(shadow_row);
char buffer[4 + (BITS_PER_LONG/8)*2];
- char shadow_buf[SHADOW_BYTES_PER_ROW];
+ char shadow_buf[META_BYTES_PER_ROW];

snprintf(buffer, sizeof(buffer),
(i == 0) ? ">%px: " : " %px: ", kaddr);
@@ -274,17 +274,17 @@ static void print_memory_metadata(const void *addr)
* function, because generic functions may try to
* access kasan mapping for the passed address.
*/
- memcpy(shadow_buf, shadow_row, SHADOW_BYTES_PER_ROW);
+ memcpy(shadow_buf, shadow_row, META_BYTES_PER_ROW);
print_hex_dump(KERN_ERR, buffer,
- DUMP_PREFIX_NONE, SHADOW_BYTES_PER_ROW, 1,
- shadow_buf, SHADOW_BYTES_PER_ROW, 0);
+ DUMP_PREFIX_NONE, META_BYTES_PER_ROW, 1,
+ shadow_buf, META_BYTES_PER_ROW, 0);

if (row_is_guilty(shadow_row, shadow))
pr_err("%*c\n",
shadow_pointer_offset(shadow_row, shadow),
'^');

- shadow_row += SHADOW_BYTES_PER_ROW;
+ shadow_row += META_BYTES_PER_ROW;
}
}

--
2.28.0.709.gb0816b6eb0-goog