kasan: rename SHADOW layout macros to META

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.

Link: https://lkml.kernel.org/r/f96244ec59dc17db35173ec352c5592b14aefaf8.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 08825fe..4148a8b 100644 (file)
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -33,11 +33,11 @@
 #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;
 
@@ -240,7 +240,7 @@ 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)
@@ -249,7 +249,7 @@ 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)
@@ -259,15 +259,15 @@ 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);
@@ -276,17 +276,17 @@ 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;
        }
 }