summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/arm64/kernel/hibernate.c5
-rw-r--r--arch/arm64/kernel/mte.c9
-rw-r--r--arch/arm64/mm/copypage.c9
-rw-r--r--arch/arm64/mm/fault.c1
-rw-r--r--arch/arm64/mm/mteswap.c9
-rw-r--r--include/linux/gfp.h2
-rw-r--r--mm/kasan/common.c3
-rw-r--r--mm/page_alloc.c19
8 files changed, 13 insertions, 44 deletions
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index 2e248342476e..af5df48ba915 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -300,11 +300,6 @@ static void swsusp_mte_restore_tags(void)
unsigned long pfn = xa_state.xa_index;
struct page *page = pfn_to_online_page(pfn);
- /*
- * It is not required to invoke page_kasan_tag_reset(page)
- * at this point since the tags stored in page->flags are
- * already restored.
- */
mte_restore_page_tags(page_address(page), tags);
mte_free_tag_storage(tags);
diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c
index f6b00743c399..b2b730233274 100644
--- a/arch/arm64/kernel/mte.c
+++ b/arch/arm64/kernel/mte.c
@@ -48,15 +48,6 @@ static void mte_sync_page_tags(struct page *page, pte_t old_pte,
if (!pte_is_tagged)
return;
- page_kasan_tag_reset(page);
- /*
- * We need smp_wmb() in between setting the flags and clearing the
- * tags because if another thread reads page->flags and builds a
- * tagged address out of it, there is an actual dependency to the
- * memory access, but on the current thread we do not guarantee that
- * the new page->flags are visible before the tags were updated.
- */
- smp_wmb();
mte_clear_page_tags(page_address(page));
}
diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c
index 0dea80bf6de4..24913271e898 100644
--- a/arch/arm64/mm/copypage.c
+++ b/arch/arm64/mm/copypage.c
@@ -23,15 +23,6 @@ void copy_highpage(struct page *to, struct page *from)
if (system_supports_mte() && test_bit(PG_mte_tagged, &from->flags)) {
set_bit(PG_mte_tagged, &to->flags);
- page_kasan_tag_reset(to);
- /*
- * We need smp_wmb() in between setting the flags and clearing the
- * tags because if another thread reads page->flags and builds a
- * tagged address out of it, there is an actual dependency to the
- * memory access, but on the current thread we do not guarantee that
- * the new page->flags are visible before the tags were updated.
- */
- smp_wmb();
mte_copy_page_tags(kto, kfrom);
}
}
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index c5e11768e5c1..cdf3ffa0c223 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -927,6 +927,5 @@ struct page *alloc_zeroed_user_highpage_movable(struct vm_area_struct *vma,
void tag_clear_highpage(struct page *page)
{
mte_zero_clear_page_tags(page_address(page));
- page_kasan_tag_reset(page);
set_bit(PG_mte_tagged, &page->flags);
}
diff --git a/arch/arm64/mm/mteswap.c b/arch/arm64/mm/mteswap.c
index a9e50e930484..4334dec93bd4 100644
--- a/arch/arm64/mm/mteswap.c
+++ b/arch/arm64/mm/mteswap.c
@@ -53,15 +53,6 @@ bool mte_restore_tags(swp_entry_t entry, struct page *page)
if (!tags)
return false;
- page_kasan_tag_reset(page);
- /*
- * We need smp_wmb() in between setting the flags and clearing the
- * tags because if another thread reads page->flags and builds a
- * tagged address out of it, there is an actual dependency to the
- * memory access, but on the current thread we do not guarantee that
- * the new page->flags are visible before the tags were updated.
- */
- smp_wmb();
mte_restore_page_tags(page_address(page), tags);
return true;
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 2d2ccae933c2..0ace7759acd2 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -348,7 +348,7 @@ struct vm_area_struct;
#define GFP_DMA32 __GFP_DMA32
#define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
#define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE | \
- __GFP_SKIP_KASAN_POISON)
+ __GFP_SKIP_KASAN_POISON | __GFP_SKIP_KASAN_UNPOISON)
#define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
__GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
#define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM)
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index c40c0e7b3b5f..78be2beb7453 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -108,9 +108,10 @@ void __kasan_unpoison_pages(struct page *page, unsigned int order, bool init)
return;
tag = kasan_random_tag();
+ kasan_unpoison(set_tag(page_address(page), tag),
+ PAGE_SIZE << order, init);
for (i = 0; i < (1 << order); i++)
page_kasan_tag_set(page + i, tag);
- kasan_unpoison(page_address(page), PAGE_SIZE << order, init);
}
void __kasan_poison_pages(struct page *page, unsigned int order, bool init)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e008a3df0485..bf45a6aa407a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2361,7 +2361,7 @@ static inline bool check_new_pcp(struct page *page, unsigned int order)
}
#endif /* CONFIG_DEBUG_VM */
-static inline bool should_skip_kasan_unpoison(gfp_t flags, bool init_tags)
+static inline bool should_skip_kasan_unpoison(gfp_t flags)
{
/* Don't skip if a software KASAN mode is enabled. */
if (IS_ENABLED(CONFIG_KASAN_GENERIC) ||
@@ -2373,12 +2373,10 @@ static inline bool should_skip_kasan_unpoison(gfp_t flags, bool init_tags)
return true;
/*
- * With hardware tag-based KASAN enabled, skip if either:
- *
- * 1. Memory tags have already been cleared via tag_clear_highpage().
- * 2. Skipping has been requested via __GFP_SKIP_KASAN_UNPOISON.
+ * With hardware tag-based KASAN enabled, skip if this has been
+ * requested via __GFP_SKIP_KASAN_UNPOISON.
*/
- return init_tags || (flags & __GFP_SKIP_KASAN_UNPOISON);
+ return flags & __GFP_SKIP_KASAN_UNPOISON;
}
static inline bool should_skip_init(gfp_t flags)
@@ -2397,6 +2395,7 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
bool init = !want_init_on_free() && want_init_on_alloc(gfp_flags) &&
!should_skip_init(gfp_flags);
bool init_tags = init && (gfp_flags & __GFP_ZEROTAGS);
+ int i;
set_page_private(page, 0);
set_page_refcounted(page);
@@ -2422,8 +2421,6 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
* should be initialized as well).
*/
if (init_tags) {
- int i;
-
/* Initialize both memory and tags. */
for (i = 0; i != 1 << order; ++i)
tag_clear_highpage(page + i);
@@ -2431,13 +2428,17 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
/* Note that memory is already initialized by the loop above. */
init = false;
}
- if (!should_skip_kasan_unpoison(gfp_flags, init_tags)) {
+ if (!should_skip_kasan_unpoison(gfp_flags)) {
/* Unpoison shadow memory or set memory tags. */
kasan_unpoison_pages(page, order, init);
/* Note that memory is already initialized by KASAN. */
if (kasan_has_integrated_init())
init = false;
+ } else {
+ /* Ensure page_address() dereferencing does not fault. */
+ for (i = 0; i != 1 << order; ++i)
+ page_kasan_tag_reset(page + i);
}
/* If memory is still not initialized, do it now. */
if (init)
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-16 11:54:23 +0000