[PATCH RFC v2 11/21] kasan: inline kasan_poison_memory and check_invalid_free

From: Andrey Konovalov
Date: Thu Oct 22 2020 - 09:20:05 EST


Using kasan_poison_memory() or check_invalid_free() currently results in
function calls. Move their definitions to mm/kasan/kasan.h and turn them
into static inline functions for hardware tag-based mode to avoid uneeded
function calls.

Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Link: https://linux-review.googlesource.com/id/Ia9d8191024a12d1374675b3d27197f10193f50bb
---
mm/kasan/hw_tags.c | 15 ---------------
mm/kasan/kasan.h | 28 ++++++++++++++++++++++++----
2 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c
index 4c24bfcfeff9..f03161f3da19 100644
--- a/mm/kasan/hw_tags.c
+++ b/mm/kasan/hw_tags.c
@@ -24,27 +24,12 @@ void __init kasan_init_tags(void)
pr_info("KernelAddressSanitizer initialized\n");
}

-void kasan_poison_memory(const void *address, size_t size, u8 value)
-{
- set_mem_tag_range(reset_tag(address),
- round_up(size, KASAN_GRANULE_SIZE), value);
-}
-
void kasan_unpoison_memory(const void *address, size_t size)
{
set_mem_tag_range(reset_tag(address),
round_up(size, KASAN_GRANULE_SIZE), get_tag(address));
}

-bool check_invalid_free(void *addr)
-{
- u8 ptr_tag = get_tag(addr);
- u8 mem_tag = get_mem_tag(addr);
-
- return (mem_tag == KASAN_TAG_INVALID) ||
- (ptr_tag != KASAN_TAG_KERNEL && ptr_tag != mem_tag);
-}
-
void kasan_set_free_info(struct kmem_cache *cache,
void *object, u8 tag)
{
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 94ba15c2f860..8d84ae6f58f1 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -153,8 +153,6 @@ struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
const void *object);

-void kasan_poison_memory(const void *address, size_t size, u8 value);
-
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)

static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
@@ -194,8 +192,6 @@ void print_tags(u8 addr_tag, const void *addr);
static inline void print_tags(u8 addr_tag, const void *addr) { }
#endif

-bool check_invalid_free(void *addr);
-
void *find_first_bad_addr(void *addr, size_t size);
const char *get_bug_type(struct kasan_access_info *info);
void metadata_fetch_row(char *buffer, void *row);
@@ -276,6 +272,30 @@ static inline u8 random_tag(void)
}
#endif

+#ifdef CONFIG_KASAN_HW_TAGS
+
+static inline void kasan_poison_memory(const void *address, size_t size, u8 value)
+{
+ set_mem_tag_range(reset_tag(address),
+ round_up(size, KASAN_GRANULE_SIZE), value);
+}
+
+static inline bool check_invalid_free(void *addr)
+{
+ u8 ptr_tag = get_tag(addr);
+ u8 mem_tag = get_mem_tag(addr);
+
+ return (mem_tag == KASAN_TAG_INVALID) ||
+ (ptr_tag != KASAN_TAG_KERNEL && ptr_tag != mem_tag);
+}
+
+#else /* CONFIG_KASAN_HW_TAGS */
+
+void kasan_poison_memory(const void *address, size_t size, u8 value);
+bool check_invalid_free(void *addr);
+
+#endif /* CONFIG_KASAN_HW_TAGS */
+
/*
* Exported functions for interfaces called from assembly or from generated
* code. Declarations here to avoid warning about missing declarations.
--
2.29.0.rc1.297.gfa9743e501-goog