From: Andrey Konovalov <[email protected]>
Drop CONFIG_KASAN_TAGS_IDENTIFY and related code to simplify making
changes to the reporting code.
The dropped functionality will be restored in the following patches in
this series.
Reviewed-by: Marco Elver <[email protected]>
Signed-off-by: Andrey Konovalov <[email protected]>
---
lib/Kconfig.kasan | 8 --------
mm/kasan/kasan.h | 12 +-----------
mm/kasan/report_tags.c | 28 ----------------------------
mm/kasan/tags.c | 21 ++-------------------
4 files changed, 3 insertions(+), 66 deletions(-)
diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index f0973da583e0..ca09b1cf8ee9 100644
--- a/lib/Kconfig.kasan
+++ b/lib/Kconfig.kasan
@@ -167,14 +167,6 @@ config KASAN_STACK
as well, as it adds inline-style instrumentation that is run
unconditionally.
-config KASAN_TAGS_IDENTIFY
- bool "Memory corruption type identification"
- depends on KASAN_SW_TAGS || KASAN_HW_TAGS
- help
- Enables best-effort identification of the bug types (use-after-free
- or out-of-bounds) at the cost of increased memory consumption.
- Only applicable for the tag-based KASAN modes.
-
config KASAN_VMALLOC
bool "Check accesses to vmalloc allocations"
depends on HAVE_ARCH_KASAN_VMALLOC
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index d401fb770f67..15c718782c1f 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -169,23 +169,13 @@ struct kasan_track {
depot_stack_handle_t stack;
};
-#if defined(CONFIG_KASAN_TAGS_IDENTIFY) && defined(CONFIG_KASAN_SW_TAGS)
-#define KASAN_NR_FREE_STACKS 5
-#else
-#define KASAN_NR_FREE_STACKS 1
-#endif
-
struct kasan_alloc_meta {
struct kasan_track alloc_track;
/* Generic mode stores free track in kasan_free_meta. */
#ifdef CONFIG_KASAN_GENERIC
depot_stack_handle_t aux_stack[2];
#else
- struct kasan_track free_track[KASAN_NR_FREE_STACKS];
-#endif
-#ifdef CONFIG_KASAN_TAGS_IDENTIFY
- u8 free_pointer_tag[KASAN_NR_FREE_STACKS];
- u8 free_track_idx;
+ struct kasan_track free_track;
#endif
};
diff --git a/mm/kasan/report_tags.c b/mm/kasan/report_tags.c
index e25d2166e813..35cf3cae4aa4 100644
--- a/mm/kasan/report_tags.c
+++ b/mm/kasan/report_tags.c
@@ -5,37 +5,9 @@
*/
#include "kasan.h"
-#include "../slab.h"
const char *kasan_get_bug_type(struct kasan_report_info *info)
{
-#ifdef CONFIG_KASAN_TAGS_IDENTIFY
- struct kasan_alloc_meta *alloc_meta;
- struct kmem_cache *cache;
- struct slab *slab;
- const void *addr;
- void *object;
- u8 tag;
- int i;
-
- tag = get_tag(info->access_addr);
- addr = kasan_reset_tag(info->access_addr);
- slab = kasan_addr_to_slab(addr);
- if (slab) {
- cache = slab->slab_cache;
- object = nearest_obj(cache, slab, (void *)addr);
- alloc_meta = kasan_get_alloc_meta(cache, object);
-
- if (alloc_meta) {
- for (i = 0; i < KASAN_NR_FREE_STACKS; i++) {
- if (alloc_meta->free_pointer_tag[i] == tag)
- return "use-after-free";
- }
- }
- return "out-of-bounds";
- }
-#endif
-
/*
* If access_size is a negative number, then it has reason to be
* defined as out-of-bounds bug type.
diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c
index 1ba3c8399f72..e0e5de8ce834 100644
--- a/mm/kasan/tags.c
+++ b/mm/kasan/tags.c
@@ -30,39 +30,22 @@ void kasan_save_free_info(struct kmem_cache *cache,
void *object, u8 tag)
{
struct kasan_alloc_meta *alloc_meta;
- u8 idx = 0;
alloc_meta = kasan_get_alloc_meta(cache, object);
if (!alloc_meta)
return;
-#ifdef CONFIG_KASAN_TAGS_IDENTIFY
- idx = alloc_meta->free_track_idx;
- alloc_meta->free_pointer_tag[idx] = tag;
- alloc_meta->free_track_idx = (idx + 1) % KASAN_NR_FREE_STACKS;
-#endif
-
- kasan_set_track(&alloc_meta->free_track[idx], GFP_NOWAIT);
+ kasan_set_track(&alloc_meta->free_track, GFP_NOWAIT);
}
struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
void *object, u8 tag)
{
struct kasan_alloc_meta *alloc_meta;
- int i = 0;
alloc_meta = kasan_get_alloc_meta(cache, object);
if (!alloc_meta)
return NULL;
-#ifdef CONFIG_KASAN_TAGS_IDENTIFY
- for (i = 0; i < KASAN_NR_FREE_STACKS; i++) {
- if (alloc_meta->free_pointer_tag[i] == tag)
- break;
- }
- if (i == KASAN_NR_FREE_STACKS)
- i = alloc_meta->free_track_idx;
-#endif
-
- return &alloc_meta->free_track[i];
+ return &alloc_meta->free_track;
}
--
2.25.1