Commit d5750edf authored by Andrey Konovalov's avatar Andrey Konovalov Committed by Linus Torvalds
Browse files

kasan: shadow declarations only for software modes 

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.

  Link: https://lkml.kernel.org/r/35126.1606402815@turing-police
  Link: https://lore.kernel.org/linux-arm-kernel/24105.1606397102@turing-police/

Link: https://lkml.kernel.org/r/e88d94eff94db883a65dca52e1736d80d28dd9bc.1606161801.git.andreyknvl@google.com


Signed-off-by: default avatarAndrey Konovalov <andreyknvl@google.com>
Signed-off-by: default avatarVincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: default avatarValdis Kletnieks <valdis.kletnieks@vt.edu>
Reviewed-by: default avatarMarco Elver <elver@google.com>
Reviewed-by: default avatarAlexander Potapenko <glider@google.com>
Tested-by: default avatarVincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
[valdis.kletnieks@vt.edu: fix build issue with asmlinkage]
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 3b1a4a86

include/linux/kasan.h

+32 −16
Original line number Diff line number Diff line
@@ -11,7 +11,7 @@ struct task_struct; 


#ifdef CONFIG_KASAN



#include <linux/pgtable.h>

#include <linux/linkage.h>

#include <asm/kasan.h>



/* kasan_data struct is used in KUnit tests for KASAN expected failures */
@@ -20,6 +20,20 @@ struct kunit_kasan_expectation { 
	bool report_found;

};



#endif



#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)



#include <linux/pgtable.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];

extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD];
@@ -35,6 +49,23 @@ 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);
@@ -75,9 +106,6 @@ 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)

{
@@ -143,14 +171,6 @@ 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; }
@@ -158,8 +178,6 @@ 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);
@@ -174,8 +192,6 @@ 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);