On Fri, Nov 13, 2020 at 11:20 PM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote: > > Using kasan_reset_tag() currently results in a function call. As it's > called quite often from the allocator code, this leads to a noticeable > slowdown. Move it to include/linux/kasan.h and turn it into a static > inline function. Also remove the now unneeded reset_tag() internal KASAN > macro and use kasan_reset_tag() instead. > > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > Reviewed-by: Marco Elver <elver@xxxxxxxxxx> Reviewed-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> > Link: https://linux-review.googlesource.com/id/I4d2061acfe91d480a75df00b07c22d8494ef14b5 > --- > include/linux/kasan.h | 5 ++++- > mm/kasan/common.c | 6 +++--- > mm/kasan/hw_tags.c | 9 ++------- > mm/kasan/kasan.h | 4 ---- > mm/kasan/report.c | 4 ++-- > mm/kasan/report_hw_tags.c | 2 +- > mm/kasan/report_sw_tags.c | 4 ++-- > mm/kasan/shadow.c | 4 ++-- > mm/kasan/sw_tags.c | 9 ++------- > 9 files changed, 18 insertions(+), 29 deletions(-) > > diff --git a/include/linux/kasan.h b/include/linux/kasan.h > index f2109bf0c5f9..1594177f86bb 100644 > --- a/include/linux/kasan.h > +++ b/include/linux/kasan.h > @@ -193,7 +193,10 @@ static inline void kasan_record_aux_stack(void *ptr) {} > > #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) > > -void *kasan_reset_tag(const void *addr); > +static inline void *kasan_reset_tag(const void *addr) > +{ > + return (void *)arch_kasan_reset_tag(addr); > +} > > bool kasan_report(unsigned long addr, size_t size, > bool is_write, unsigned long ip); > diff --git a/mm/kasan/common.c b/mm/kasan/common.c > index fabd843eff3d..1ac4f435c679 100644 > --- a/mm/kasan/common.c > +++ b/mm/kasan/common.c > @@ -180,14 +180,14 @@ size_t kasan_metadata_size(struct kmem_cache *cache) > struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache, > const void *object) > { > - return (void *)reset_tag(object) + cache->kasan_info.alloc_meta_offset; > + return kasan_reset_tag(object) + cache->kasan_info.alloc_meta_offset; > } > > struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache, > const void *object) > { > BUILD_BUG_ON(sizeof(struct kasan_free_meta) > 32); > - return (void *)reset_tag(object) + cache->kasan_info.free_meta_offset; > + return kasan_reset_tag(object) + cache->kasan_info.free_meta_offset; > } > > void kasan_poison_slab(struct page *page) > @@ -284,7 +284,7 @@ static bool __kasan_slab_free(struct kmem_cache *cache, void *object, > > tag = get_tag(object); > tagged_object = object; > - object = reset_tag(object); > + object = kasan_reset_tag(object); > > if (is_kfence_address(object)) > return false; > diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c > index 68e77363e58b..a34476764f1d 100644 > --- a/mm/kasan/hw_tags.c > +++ b/mm/kasan/hw_tags.c > @@ -31,18 +31,13 @@ void __init kasan_init_hw_tags(void) > pr_info("KernelAddressSanitizer initialized\n"); > } > > -void *kasan_reset_tag(const void *addr) > -{ > - return reset_tag(addr); > -} > - > void poison_range(const void *address, size_t size, u8 value) > { > /* Skip KFENCE memory if called explicitly outside of sl*b. */ > if (is_kfence_address(address)) > return; > > - hw_set_mem_tag_range(reset_tag(address), > + hw_set_mem_tag_range(kasan_reset_tag(address), > round_up(size, KASAN_GRANULE_SIZE), value); > } > > @@ -52,7 +47,7 @@ void unpoison_range(const void *address, size_t size) > if (is_kfence_address(address)) > return; > > - hw_set_mem_tag_range(reset_tag(address), > + hw_set_mem_tag_range(kasan_reset_tag(address), > round_up(size, KASAN_GRANULE_SIZE), get_tag(address)); > } > > diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h > index 0eab7e4cecb8..5e8cd2080369 100644 > --- a/mm/kasan/kasan.h > +++ b/mm/kasan/kasan.h > @@ -248,15 +248,11 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > return addr; > } > #endif > -#ifndef arch_kasan_reset_tag > -#define arch_kasan_reset_tag(addr) ((void *)(addr)) > -#endif > #ifndef arch_kasan_get_tag > #define arch_kasan_get_tag(addr) 0 > #endif > > #define set_tag(addr, tag) ((void *)arch_kasan_set_tag((addr), (tag))) > -#define reset_tag(addr) ((void *)arch_kasan_reset_tag(addr)) > #define get_tag(addr) arch_kasan_get_tag(addr) > > #ifdef CONFIG_KASAN_HW_TAGS > diff --git a/mm/kasan/report.c b/mm/kasan/report.c > index df16bef0d810..76a0e3ae2049 100644 > --- a/mm/kasan/report.c > +++ b/mm/kasan/report.c > @@ -328,7 +328,7 @@ void kasan_report_invalid_free(void *object, unsigned long ip) > unsigned long flags; > u8 tag = get_tag(object); > > - object = reset_tag(object); > + object = kasan_reset_tag(object); > > #if IS_ENABLED(CONFIG_KUNIT) > if (current->kunit_test) > @@ -361,7 +361,7 @@ static void __kasan_report(unsigned long addr, size_t size, bool is_write, > disable_trace_on_warning(); > > tagged_addr = (void *)addr; > - untagged_addr = reset_tag(tagged_addr); > + untagged_addr = kasan_reset_tag(tagged_addr); > > info.access_addr = tagged_addr; > if (addr_has_metadata(untagged_addr)) > diff --git a/mm/kasan/report_hw_tags.c b/mm/kasan/report_hw_tags.c > index da543eb832cd..57114f0e14d1 100644 > --- a/mm/kasan/report_hw_tags.c > +++ b/mm/kasan/report_hw_tags.c > @@ -22,7 +22,7 @@ const char *get_bug_type(struct kasan_access_info *info) > > void *find_first_bad_addr(void *addr, size_t size) > { > - return reset_tag(addr); > + return kasan_reset_tag(addr); > } > > void metadata_fetch_row(char *buffer, void *row) > diff --git a/mm/kasan/report_sw_tags.c b/mm/kasan/report_sw_tags.c > index 317100fd95b9..7604b46239d4 100644 > --- a/mm/kasan/report_sw_tags.c > +++ b/mm/kasan/report_sw_tags.c > @@ -41,7 +41,7 @@ const char *get_bug_type(struct kasan_access_info *info) > int i; > > tag = get_tag(info->access_addr); > - addr = reset_tag(info->access_addr); > + addr = kasan_reset_tag(info->access_addr); > page = kasan_addr_to_page(addr); > if (page && PageSlab(page)) { > cache = page->slab_cache; > @@ -72,7 +72,7 @@ const char *get_bug_type(struct kasan_access_info *info) > void *find_first_bad_addr(void *addr, size_t size) > { > u8 tag = get_tag(addr); > - void *p = reset_tag(addr); > + void *p = kasan_reset_tag(addr); > void *end = p + size; > > while (p < end && tag == *(u8 *)kasan_mem_to_shadow(p)) > diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c > index d8a122f887a0..37153bd1c126 100644 > --- a/mm/kasan/shadow.c > +++ b/mm/kasan/shadow.c > @@ -82,7 +82,7 @@ void poison_range(const void *address, size_t size, u8 value) > * some of the callers (e.g. kasan_poison_object_data) pass tagged > * addresses to this function. > */ > - address = reset_tag(address); > + address = kasan_reset_tag(address); > > /* Skip KFENCE memory if called explicitly outside of sl*b. */ > if (is_kfence_address(address)) > @@ -103,7 +103,7 @@ void unpoison_range(const void *address, size_t size) > * some of the callers (e.g. kasan_unpoison_object_data) pass tagged > * addresses to this function. > */ > - address = reset_tag(address); > + address = kasan_reset_tag(address); > > /* > * Skip KFENCE memory if called explicitly outside of sl*b. Also note > diff --git a/mm/kasan/sw_tags.c b/mm/kasan/sw_tags.c > index 6d7648cc3b98..e17de2619bbf 100644 > --- a/mm/kasan/sw_tags.c > +++ b/mm/kasan/sw_tags.c > @@ -67,11 +67,6 @@ u8 random_tag(void) > return (u8)(state % (KASAN_TAG_MAX + 1)); > } > > -void *kasan_reset_tag(const void *addr) > -{ > - return reset_tag(addr); > -} > - > bool check_memory_region(unsigned long addr, size_t size, bool write, > unsigned long ret_ip) > { > @@ -107,7 +102,7 @@ bool check_memory_region(unsigned long addr, size_t size, bool write, > if (tag == KASAN_TAG_KERNEL) > return true; > > - untagged_addr = reset_tag((const void *)addr); > + untagged_addr = kasan_reset_tag((const void *)addr); > if (unlikely(untagged_addr < > kasan_shadow_to_mem((void *)KASAN_SHADOW_START))) { > return !kasan_report(addr, size, write, ret_ip); > @@ -126,7 +121,7 @@ bool check_memory_region(unsigned long addr, size_t size, bool write, > bool check_invalid_free(void *addr) > { > u8 tag = get_tag(addr); > - u8 shadow_byte = READ_ONCE(*(u8 *)kasan_mem_to_shadow(reset_tag(addr))); > + u8 shadow_byte = READ_ONCE(*(u8 *)kasan_mem_to_shadow(kasan_reset_tag(addr))); > > return (shadow_byte == KASAN_TAG_INVALID) || > (tag != KASAN_TAG_KERNEL && tag != shadow_byte); > -- > 2.29.2.299.gdc1121823c-goog >
