[PATCH v5 13/40] kasan: shadow declarations only for software modes
From: Andrey Konovalov
Date: Mon Oct 12 2020 - 16:45:37 EST
This is a preparatory commit for the upcoming addition of a new hardware
tag-based (MTE-based) KASAN mode.
Group shadow-related KASAN function declarations and only define them
for the two existing software modes.
No functional changes for software modes.
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Reviewed-by: Marco Elver <elver@xxxxxxxxxx>
---
Change-Id: I864be75a88b91b443c55e9c2042865e15703e164
---
include/linux/kasan.h | 45 ++++++++++++++++++++++++++++---------------
1 file changed, 29 insertions(+), 16 deletions(-)
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index bd5b4965a269..1ff2717a8547 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -10,9 +10,20 @@ struct vm_struct;
struct task_struct;
#ifdef CONFIG_KASAN
+#include <asm/kasan.h>
+#endif
+
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
#include <linux/pgtable.h>
-#include <asm/kasan.h>
+
+/* Software KASAN implementations use shadow memory. */
+
+#ifdef CONFIG_KASAN_SW_TAGS
+#define KASAN_SHADOW_INIT 0xFF
+#else
+#define KASAN_SHADOW_INIT 0
+#endif
extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE];
@@ -29,6 +40,23 @@ static inline void *kasan_mem_to_shadow(const void *addr)
+ KASAN_SHADOW_OFFSET;
}
+int kasan_add_zero_shadow(void *start, unsigned long size);
+void kasan_remove_zero_shadow(void *start, unsigned long size);
+
+#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
+
+static inline int kasan_add_zero_shadow(void *start, unsigned long size)
+{
+ return 0;
+}
+static inline void kasan_remove_zero_shadow(void *start,
+ unsigned long size)
+{}
+
+#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
+
+#ifdef CONFIG_KASAN
+
/* Enable reporting bugs after kasan_disable_current() */
extern void kasan_enable_current(void);
@@ -69,9 +97,6 @@ struct kasan_cache {
int free_meta_offset;
};
-int kasan_add_zero_shadow(void *start, unsigned long size);
-void kasan_remove_zero_shadow(void *start, unsigned long size);
-
size_t __ksize(const void *);
static inline void kasan_unpoison_slab(const void *ptr)
{
@@ -137,14 +162,6 @@ static inline bool kasan_slab_free(struct kmem_cache *s, void *object,
return false;
}
-static inline int kasan_add_zero_shadow(void *start, unsigned long size)
-{
- return 0;
-}
-static inline void kasan_remove_zero_shadow(void *start,
- unsigned long size)
-{}
-
static inline void kasan_unpoison_slab(const void *ptr) { }
static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; }
@@ -152,8 +169,6 @@ static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; }
#ifdef CONFIG_KASAN_GENERIC
-#define KASAN_SHADOW_INIT 0
-
void kasan_cache_shrink(struct kmem_cache *cache);
void kasan_cache_shutdown(struct kmem_cache *cache);
void kasan_record_aux_stack(void *ptr);
@@ -168,8 +183,6 @@ static inline void kasan_record_aux_stack(void *ptr) {}
#ifdef CONFIG_KASAN_SW_TAGS
-#define KASAN_SHADOW_INIT 0xFF
-
void kasan_init_tags(void);
void *kasan_reset_tag(const void *addr);
--
2.28.0.1011.ga647a8990f-goog