From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Add bug_type and alloc/free_track fields to kasan_report_info and add a
kasan_complete_mode_report_info() function that fills in these fields.
This function is implemented differently for different KASAN mode.
Change the reporting code to use the filled in fields instead of
invoking kasan_get_bug_type() and kasan_get_alloc/free_track().
For the Generic mode, kasan_complete_mode_report_info() invokes these
functions instead. For the tag-based modes, only the bug_type field is
filled in; alloc/free_track are handled in the next patch.
Using a single function that fills in these fields is required for the
tag-based modes, as the values for all three fields are determined in a
single procedure implemented in the following patch.
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
---
mm/kasan/kasan.h | 33 +++++++++++++++++----------------
mm/kasan/report.c | 29 ++++++++++++++---------------
mm/kasan/report_generic.c | 32 +++++++++++++++++---------------
mm/kasan/report_tags.c | 13 +++----------
4 files changed, 51 insertions(+), 56 deletions(-)
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index b9bd9f1656bf..c51cea31ced0 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -146,6 +146,13 @@ static inline bool kasan_requires_meta(void)
#define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE)
#define META_ROWS_AROUND_ADDR 2
+#define KASAN_STACK_DEPTH 64
+
+struct kasan_track {
+ u32 pid;
+ depot_stack_handle_t stack;
+};
+
struct kasan_report_info {
/* Filled in by kasan_report_*(). */
void *access_addr;
@@ -158,6 +165,11 @@ struct kasan_report_info {
void *first_bad_addr;
struct kmem_cache *cache;
void *object;
+
+ /* Filled in by the mode-specific reporting code. */
+ const char *bug_type;
+ struct kasan_track alloc_track;
+ struct kasan_track free_track;
};
/* Do not change the struct layout: compiler ABI. */
@@ -183,14 +195,7 @@ struct kasan_global {
#endif
};
-/* Structures for keeping alloc and free tracks. */
-
-#define KASAN_STACK_DEPTH 64
-
-struct kasan_track {
- u32 pid;
- depot_stack_handle_t stack;
-};
+/* Structures for keeping alloc and free meta. */
#ifdef CONFIG_KASAN_GENERIC
@@ -264,16 +269,16 @@ static inline bool addr_has_metadata(const void *addr)
#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
+void *kasan_find_first_bad_addr(void *addr, size_t size);
+void kasan_complete_mode_report_info(struct kasan_report_info *info);
+void kasan_metadata_fetch_row(char *buffer, void *row);
+
#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
void kasan_print_tags(u8 addr_tag, const void *addr);
#else
static inline void kasan_print_tags(u8 addr_tag, const void *addr) { }
#endif
-void *kasan_find_first_bad_addr(void *addr, size_t size);
-const char *kasan_get_bug_type(struct kasan_report_info *info);
-void kasan_metadata_fetch_row(char *buffer, void *row);
-
#if defined(CONFIG_KASAN_STACK)
void kasan_print_address_stack_frame(const void *addr);
#else
@@ -308,10 +313,6 @@ depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
void kasan_set_track(struct kasan_track *track, gfp_t flags);
void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags);
void kasan_save_free_info(struct kmem_cache *cache, void *object);
-struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
- void *object);
-struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
- void *object, u8 tag);
#if defined(CONFIG_KASAN_GENERIC) && \
(defined(CONFIG_SLAB) || defined(CONFIG_SLUB))
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index a2789d4a05dd..206b7fe64e6b 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -176,7 +176,7 @@ static void end_report(unsigned long *flags, void *addr)
static void print_error_description(struct kasan_report_info *info)
{
const char *bug_type = info->is_free ?
- "double-free or invalid-free" : kasan_get_bug_type(info);
+ "double-free or invalid-free" : info->bug_type;
pr_err("BUG: KASAN: %s in %pS\n", bug_type, (void *)info->ip);
if (info->is_free)
@@ -236,31 +236,25 @@ static void describe_object_addr(const void *addr, struct kmem_cache *cache,
(void *)(object_addr + cache->object_size));
}
-static void describe_object_stacks(u8 tag, struct kasan_report_info *info)
+static void describe_object_stacks(struct kasan_report_info *info)
{
- struct kasan_track *alloc_track;
- struct kasan_track *free_track;
-
- alloc_track = kasan_get_alloc_track(info->cache, info->object);
- if (alloc_track) {
- print_track(alloc_track, "Allocated");
+ if (info->alloc_track.stack) {
+ print_track(&info->alloc_track, "Allocated");
pr_err("\n");
}
- free_track = kasan_get_free_track(info->cache, info->object, tag);
- if (free_track) {
- print_track(free_track, "Freed");
+ if (info->free_track.stack) {
+ print_track(&info->free_track, "Freed");
pr_err("\n");
}
kasan_print_aux_stacks(info->cache, info->object);
}
-static void describe_object(const void *addr, u8 tag,
- struct kasan_report_info *info)
+static void describe_object(const void *addr, struct kasan_report_info *info)
{
if (kasan_stack_collection_enabled())
- describe_object_stacks(tag, info);
+ describe_object_stacks(info);
describe_object_addr(addr, info->cache, info->object);
}
@@ -289,7 +283,7 @@ static void print_address_description(void *addr, u8 tag,
pr_err("\n");
if (info->cache && info->object) {
- describe_object(addr, tag, info);
+ describe_object(addr, info);
pr_err("\n");
}
@@ -420,6 +414,9 @@ static void complete_report_info(struct kasan_report_info *info)
info->object = nearest_obj(info->cache, slab, addr);
} else
info->cache = info->object = NULL;
+
+ /* Fill in mode-specific report info fields. */
+ kasan_complete_mode_report_info(info);
}
void kasan_report_invalid_free(void *ptr, unsigned long ip)
@@ -437,6 +434,7 @@ void kasan_report_invalid_free(void *ptr, unsigned long ip)
start_report(&flags, true);
+ memset(&info, 0, sizeof(info));
info.access_addr = ptr;
info.access_size = 0;
info.is_write = false;
@@ -471,6 +469,7 @@ bool kasan_report(unsigned long addr, size_t size, bool is_write,
start_report(&irq_flags, true);
+ memset(&info, 0, sizeof(info));
info.access_addr = ptr;
info.access_size = size;
info.is_write = is_write;
diff --git a/mm/kasan/report_generic.c b/mm/kasan/report_generic.c
index 74d21786ef09..087c1d8c8145 100644
--- a/mm/kasan/report_generic.c
+++ b/mm/kasan/report_generic.c
@@ -109,7 +109,7 @@ static const char *get_wild_bug_type(struct kasan_report_info *info)
return bug_type;
}
-const char *kasan_get_bug_type(struct kasan_report_info *info)
+static const char *get_bug_type(struct kasan_report_info *info)
{
/*
* If access_size is a negative number, then it has reason to be
@@ -127,25 +127,27 @@ const char *kasan_get_bug_type(struct kasan_report_info *info)
return get_wild_bug_type(info);
}
-struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
- void *object)
+void kasan_complete_mode_report_info(struct kasan_report_info *info)
{
struct kasan_alloc_meta *alloc_meta;
+ struct kasan_free_meta *free_meta;
- alloc_meta = kasan_get_alloc_meta(cache, object);
- if (!alloc_meta)
- return NULL;
+ info->bug_type = get_bug_type(info);
- return &alloc_meta->alloc_track;
-}
+ if (!info->cache || !info->object)
+ return;
-struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
- void *object, u8 tag)
-{
- if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREETRACK)
- return NULL;
- /* Free meta must be present with KASAN_SLAB_FREETRACK. */
- return &kasan_get_free_meta(cache, object)->free_track;
+ alloc_meta = kasan_get_alloc_meta(info->cache, info->object);
+ if (alloc_meta)
+ memcpy(&info->alloc_track, &alloc_meta->alloc_track,
+ sizeof(info->alloc_track));
+
+ if (*(u8 *)kasan_mem_to_shadow(info->object) == KASAN_SLAB_FREETRACK) {
+ /* Free meta must be present with KASAN_SLAB_FREETRACK. */
+ free_meta = kasan_get_free_meta(info->cache, info->object);
+ memcpy(&info->free_track, &free_meta->free_track,
+ sizeof(info->free_track));
+ }
}
void kasan_metadata_fetch_row(char *buffer, void *row)
diff --git a/mm/kasan/report_tags.c b/mm/kasan/report_tags.c
index 79b6497d8a81..5cbac2cdb177 100644
--- a/mm/kasan/report_tags.c
+++ b/mm/kasan/report_tags.c
@@ -6,7 +6,7 @@
#include "kasan.h"
-const char *kasan_get_bug_type(struct kasan_report_info *info)
+static const char *get_bug_type(struct kasan_report_info *info)
{
/*
* If access_size is a negative number, then it has reason to be
@@ -22,14 +22,7 @@ const char *kasan_get_bug_type(struct kasan_report_info *info)
return "invalid-access";
}
-struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
- void *object)
+void kasan_complete_mode_report_info(struct kasan_report_info *info)
{
- return NULL;
-}
-
-struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
- void *object, u8 tag)
-{
- return NULL;
+ info->bug_type = get_bug_type(info);
}
--
2.25.1
