1 files changed, 34 insertions, 10 deletions

diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 0e5f965f1882..621782100eaa 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -111,7 +111,7 @@ static void print_track(struct kasan_track *track, const char *prefix)
 	}
 }
 
-static struct page *addr_to_page(const void *addr)
+struct page *kasan_addr_to_page(const void *addr)
 {
 	if ((addr >= (void *)PAGE_OFFSET) &&
 			(addr < high_memory))
@@ -151,15 +151,38 @@ static void describe_object_addr(struct kmem_cache *cache, void *object,
 		(void *)(object_addr + cache->object_size));
 }
 
+static 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 = get_alloc_info(cache, object);
+
+#ifdef CONFIG_KASAN_SW_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];
+}
+
 static void describe_object(struct kmem_cache *cache, void *object,
-				const void *addr)
+				const void *addr, u8 tag)
 {
 	struct kasan_alloc_meta *alloc_info = get_alloc_info(cache, object);
 
 	if (cache->flags & SLAB_KASAN) {
+		struct kasan_track *free_track;
+
 		print_track(&alloc_info->alloc_track, "Allocated");
 		pr_err("\n");
-		print_track(&alloc_info->free_track, "Freed");
+		free_track = kasan_get_free_track(cache, object, tag);
+		print_track(free_track, "Freed");
 		pr_err("\n");
 	}
 
@@ -344,9 +367,9 @@ static void print_address_stack_frame(const void *addr)
 	print_decoded_frame_descr(frame_descr);
 }
 
-static void print_address_description(void *addr)
+static void print_address_description(void *addr, u8 tag)
 {
-	struct page *page = addr_to_page(addr);
+	struct page *page = kasan_addr_to_page(addr);
 
 	dump_stack();
 	pr_err("\n");
@@ -355,7 +378,7 @@ static void print_address_description(void *addr)
 		struct kmem_cache *cache = page->slab_cache;
 		void *object = nearest_obj(cache, page,	addr);
 
-		describe_object(cache, object, addr);
+		describe_object(cache, object, addr, tag);
 	}
 
 	if (kernel_or_module_addr(addr) && !init_task_stack_addr(addr)) {
@@ -435,13 +458,14 @@ static bool report_enabled(void)
 void kasan_report_invalid_free(void *object, unsigned long ip)
 {
 	unsigned long flags;
+	u8 tag = get_tag(object);
 
+	object = reset_tag(object);
 	start_report(&flags);
 	pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", (void *)ip);
-	print_tags(get_tag(object), reset_tag(object));
-	object = reset_tag(object);
+	print_tags(tag, object);
 	pr_err("\n");
-	print_address_description(object);
+	print_address_description(object, tag);
 	pr_err("\n");
 	print_shadow_for_address(object);
 	end_report(&flags);
@@ -479,7 +503,7 @@ void __kasan_report(unsigned long addr, size_t size, bool is_write, unsigned lon
 	pr_err("\n");
 
 	if (addr_has_shadow(untagged_addr)) {
-		print_address_description(untagged_addr);
+		print_address_description(untagged_addr, get_tag(tagged_addr));
 		pr_err("\n");
 		print_shadow_for_address(info.first_bad_addr);
 	} else {