kasan: update reported bug types for kernel memory accesses

Update the names of the bad access types to better reflect the type of
the access that happended and make these error types "literals" that can
be used for classification and deduplication in scripts.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/kasan/report.c

@@ -49,7 +49,7 @@ static const void *find_first_bad_addr(const void *addr, size_t size)
 
 static void print_error_description(struct kasan_access_info *info)
 {
-	const char *bug_type = "unknown crash";
+	const char *bug_type = "unknown-crash";
 	u8 shadow_val;
 
 	info->first_bad_addr = find_first_bad_addr(info->access_addr,
@@ -58,21 +58,25 @@ static void print_error_description(struct kasan_access_info *info)
 	shadow_val = *(u8 *)kasan_mem_to_shadow(info->first_bad_addr);
 
 	switch (shadow_val) {
-	case KASAN_FREE_PAGE:
-	case KASAN_KMALLOC_FREE:
-		bug_type = "use after free";
+	case 0 ... KASAN_SHADOW_SCALE_SIZE - 1:
+		bug_type = "out-of-bounds";
 		break;
 	case KASAN_PAGE_REDZONE:
 	case KASAN_KMALLOC_REDZONE:
+		bug_type = "slab-out-of-bounds";
+		break;
 	case KASAN_GLOBAL_REDZONE:
-	case 0 ... KASAN_SHADOW_SCALE_SIZE - 1:
-		bug_type = "out of bounds access";
+		bug_type = "global-out-of-bounds";
 		break;
 	case KASAN_STACK_LEFT:
 	case KASAN_STACK_MID:
 	case KASAN_STACK_RIGHT:
 	case KASAN_STACK_PARTIAL:
-		bug_type = "out of bounds on stack";
+		bug_type = "stack-out-of-bounds";
+		break;
+	case KASAN_FREE_PAGE:
+	case KASAN_KMALLOC_FREE:
+		bug_type = "use-after-free";
 		break;
 	}