mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 09:59:32 +00:00
arm64: kasan: simplify and inline MTE functions
This change provides a simpler implementation of mte_get_mem_tag(), mte_get_random_tag(), and mte_set_mem_tag_range(). Simplifications include removing system_supports_mte() checks as these functions are onlye called from KASAN runtime that had already checked system_supports_mte(). Besides that, size and address alignment checks are removed from mte_set_mem_tag_range(), as KASAN now does those. This change also moves these functions into the asm/mte-kasan.h header and implements mte_set_mem_tag_range() via inline assembly to avoid unnecessary functions calls. [vincenzo.frascino@arm.com: fix warning in mte_get_random_tag()] Link: https://lkml.kernel.org/r/20210211152208.23811-1-vincenzo.frascino@arm.com Link: https://lkml.kernel.org/r/a26121b294fdf76e369cb7a74351d1c03a908930.1612546384.git.andreyknvl@google.com Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Marco Elver <elver@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
cde8a7eb77
commit
2cb3427642
7 changed files with 61 additions and 74 deletions
|
@ -6,7 +6,6 @@
|
|||
#define __ASM_CACHE_H
|
||||
|
||||
#include <asm/cputype.h>
|
||||
#include <asm/mte-kasan.h>
|
||||
|
||||
#define CTR_L1IP_SHIFT 14
|
||||
#define CTR_L1IP_MASK 3
|
||||
|
|
|
@ -6,6 +6,7 @@
|
|||
|
||||
#include <linux/linkage.h>
|
||||
#include <asm/memory.h>
|
||||
#include <asm/mte-kasan.h>
|
||||
#include <asm/pgtable-types.h>
|
||||
|
||||
#define arch_kasan_set_tag(addr, tag) __tag_set(addr, tag)
|
||||
|
|
|
@ -11,4 +11,6 @@
|
|||
#define MTE_TAG_SIZE 4
|
||||
#define MTE_TAG_MASK GENMASK((MTE_TAG_SHIFT + (MTE_TAG_SIZE - 1)), MTE_TAG_SHIFT)
|
||||
|
||||
#define __MTE_PREAMBLE ARM64_ASM_PREAMBLE ".arch_extension memtag\n"
|
||||
|
||||
#endif /* __ASM_MTE_DEF_H */
|
||||
|
|
|
@ -11,12 +11,15 @@
|
|||
|
||||
#include <linux/types.h>
|
||||
|
||||
/*
|
||||
* The functions below are meant to be used only for the
|
||||
* KASAN_HW_TAGS interface defined in asm/memory.h.
|
||||
*/
|
||||
#ifdef CONFIG_ARM64_MTE
|
||||
|
||||
/*
|
||||
* These functions are meant to be only used from KASAN runtime through
|
||||
* the arch_*() interface defined in asm/memory.h.
|
||||
* These functions don't include system_supports_mte() checks,
|
||||
* as KASAN only calls them when MTE is supported and enabled.
|
||||
*/
|
||||
|
||||
static inline u8 mte_get_ptr_tag(void *ptr)
|
||||
{
|
||||
/* Note: The format of KASAN tags is 0xF<x> */
|
||||
|
@ -25,9 +28,54 @@ static inline u8 mte_get_ptr_tag(void *ptr)
|
|||
return tag;
|
||||
}
|
||||
|
||||
u8 mte_get_mem_tag(void *addr);
|
||||
u8 mte_get_random_tag(void);
|
||||
void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag);
|
||||
/* Get allocation tag for the address. */
|
||||
static inline u8 mte_get_mem_tag(void *addr)
|
||||
{
|
||||
asm(__MTE_PREAMBLE "ldg %0, [%0]"
|
||||
: "+r" (addr));
|
||||
|
||||
return mte_get_ptr_tag(addr);
|
||||
}
|
||||
|
||||
/* Generate a random tag. */
|
||||
static inline u8 mte_get_random_tag(void)
|
||||
{
|
||||
void *addr;
|
||||
|
||||
asm(__MTE_PREAMBLE "irg %0, %0"
|
||||
: "=r" (addr));
|
||||
|
||||
return mte_get_ptr_tag(addr);
|
||||
}
|
||||
|
||||
/*
|
||||
* Assign allocation tags for a region of memory based on the pointer tag.
|
||||
* Note: The address must be non-NULL and MTE_GRANULE_SIZE aligned and
|
||||
* size must be non-zero and MTE_GRANULE_SIZE aligned.
|
||||
*/
|
||||
static inline void mte_set_mem_tag_range(void *addr, size_t size, u8 tag)
|
||||
{
|
||||
u64 curr, end;
|
||||
|
||||
if (!size)
|
||||
return;
|
||||
|
||||
curr = (u64)__tag_set(addr, tag);
|
||||
end = curr + size;
|
||||
|
||||
do {
|
||||
/*
|
||||
* 'asm volatile' is required to prevent the compiler to move
|
||||
* the statement outside of the loop.
|
||||
*/
|
||||
asm volatile(__MTE_PREAMBLE "stg %0, [%0]"
|
||||
:
|
||||
: "r" (curr)
|
||||
: "memory");
|
||||
|
||||
curr += MTE_GRANULE_SIZE;
|
||||
} while (curr != end);
|
||||
}
|
||||
|
||||
void mte_enable_kernel(void);
|
||||
void mte_init_tags(u64 max_tag);
|
||||
|
@ -46,13 +94,14 @@ static inline u8 mte_get_mem_tag(void *addr)
|
|||
{
|
||||
return 0xFF;
|
||||
}
|
||||
|
||||
static inline u8 mte_get_random_tag(void)
|
||||
{
|
||||
return 0xFF;
|
||||
}
|
||||
static inline void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag)
|
||||
|
||||
static inline void mte_set_mem_tag_range(void *addr, size_t size, u8 tag)
|
||||
{
|
||||
return addr;
|
||||
}
|
||||
|
||||
static inline void mte_enable_kernel(void)
|
||||
|
|
|
@ -8,8 +8,6 @@
|
|||
#include <asm/compiler.h>
|
||||
#include <asm/mte-def.h>
|
||||
|
||||
#define __MTE_PREAMBLE ARM64_ASM_PREAMBLE ".arch_extension memtag\n"
|
||||
|
||||
#ifndef __ASSEMBLY__
|
||||
|
||||
#include <linux/bitfield.h>
|
||||
|
|
|
@ -19,7 +19,6 @@
|
|||
#include <asm/barrier.h>
|
||||
#include <asm/cpufeature.h>
|
||||
#include <asm/mte.h>
|
||||
#include <asm/mte-kasan.h>
|
||||
#include <asm/ptrace.h>
|
||||
#include <asm/sysreg.h>
|
||||
|
||||
|
@ -88,51 +87,6 @@ int memcmp_pages(struct page *page1, struct page *page2)
|
|||
return ret;
|
||||
}
|
||||
|
||||
u8 mte_get_mem_tag(void *addr)
|
||||
{
|
||||
if (!system_supports_mte())
|
||||
return 0xFF;
|
||||
|
||||
asm(__MTE_PREAMBLE "ldg %0, [%0]"
|
||||
: "+r" (addr));
|
||||
|
||||
return mte_get_ptr_tag(addr);
|
||||
}
|
||||
|
||||
u8 mte_get_random_tag(void)
|
||||
{
|
||||
void *addr;
|
||||
|
||||
if (!system_supports_mte())
|
||||
return 0xFF;
|
||||
|
||||
asm(__MTE_PREAMBLE "irg %0, %0"
|
||||
: "+r" (addr));
|
||||
|
||||
return mte_get_ptr_tag(addr);
|
||||
}
|
||||
|
||||
void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag)
|
||||
{
|
||||
void *ptr = addr;
|
||||
|
||||
if ((!system_supports_mte()) || (size == 0))
|
||||
return addr;
|
||||
|
||||
/* Make sure that size is MTE granule aligned. */
|
||||
WARN_ON(size & (MTE_GRANULE_SIZE - 1));
|
||||
|
||||
/* Make sure that the address is MTE granule aligned. */
|
||||
WARN_ON((u64)addr & (MTE_GRANULE_SIZE - 1));
|
||||
|
||||
tag = 0xF0 | tag;
|
||||
ptr = (void *)__tag_set(ptr, tag);
|
||||
|
||||
mte_assign_mem_tag_range(ptr, size);
|
||||
|
||||
return ptr;
|
||||
}
|
||||
|
||||
void mte_init_tags(u64 max_tag)
|
||||
{
|
||||
static bool gcr_kernel_excl_initialized;
|
||||
|
|
|
@ -149,19 +149,3 @@ SYM_FUNC_START(mte_restore_page_tags)
|
|||
|
||||
ret
|
||||
SYM_FUNC_END(mte_restore_page_tags)
|
||||
|
||||
/*
|
||||
* Assign allocation tags for a region of memory based on the pointer tag
|
||||
* x0 - source pointer
|
||||
* x1 - size
|
||||
*
|
||||
* Note: The address must be non-NULL and MTE_GRANULE_SIZE aligned and
|
||||
* size must be non-zero and MTE_GRANULE_SIZE aligned.
|
||||
*/
|
||||
SYM_FUNC_START(mte_assign_mem_tag_range)
|
||||
1: stg x0, [x0]
|
||||
add x0, x0, #MTE_GRANULE_SIZE
|
||||
subs x1, x1, #MTE_GRANULE_SIZE
|
||||
b.gt 1b
|
||||
ret
|
||||
SYM_FUNC_END(mte_assign_mem_tag_range)
|
||||
|
|
Loading…
Reference in a new issue