30 files changed, 1799 insertions, 1258 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index 4275c25b5d8a..f730605b8dcf 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -713,7 +713,7 @@ config ZSMALLOC_STAT
 	select DEBUG_FS
 	help
 	  This option enables code in the zsmalloc to collect various
-	  statistics about whats happening in zsmalloc and exports that
+	  statistics about what's happening in zsmalloc and exports that
 	  information to userspace via debugfs.
 	  If unsure, say N.
 
diff --git a/mm/filemap.c b/mm/filemap.c
index 7a49bac48aea..5c9d564317a5 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2453,6 +2453,9 @@ ssize_t generic_file_buffered_read(struct kiocb *iocb,
 
 	if (unlikely(iocb->ki_pos >= inode->i_sb->s_maxbytes))
 		return 0;
+	if (unlikely(!iov_iter_count(iter)))
+		return 0;
+
 	iov_iter_truncate(iter, inode->i_sb->s_maxbytes);
 
 	if (nr_pages > ARRAY_SIZE(pages_onstack))
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index cbf32d2824fd..a2602969873d 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4105,10 +4105,30 @@ retry_avoidcopy:
 		 * may get SIGKILLed if it later faults.
 		 */
 		if (outside_reserve) {
+			struct address_space *mapping = vma->vm_file->f_mapping;
+			pgoff_t idx;
+			u32 hash;
+
 			put_page(old_page);
 			BUG_ON(huge_pte_none(pte));
+			/*
+			 * Drop hugetlb_fault_mutex and i_mmap_rwsem before
+			 * unmapping.  unmapping needs to hold i_mmap_rwsem
+			 * in write mode.  Dropping i_mmap_rwsem in read mode
+			 * here is OK as COW mappings do not interact with
+			 * PMD sharing.
+			 *
+			 * Reacquire both after unmap operation.
+			 */
+			idx = vma_hugecache_offset(h, vma, haddr);
+			hash = hugetlb_fault_mutex_hash(mapping, idx);
+			mutex_unlock(&hugetlb_fault_mutex_table[hash]);
+			i_mmap_unlock_read(mapping);
+
 			unmap_ref_private(mm, vma, old_page, haddr);
-			BUG_ON(huge_pte_none(pte));
+
+			i_mmap_lock_read(mapping);
+			mutex_lock(&hugetlb_fault_mutex_table[hash]);
 			spin_lock(ptl);
 			ptep = huge_pte_offset(mm, haddr, huge_page_size(h));
 			if (likely(ptep &&
diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile
index 370d970e5ab5..9fe39a66388a 100644
--- a/mm/kasan/Makefile
+++ b/mm/kasan/Makefile
@@ -6,12 +6,15 @@ KCOV_INSTRUMENT := n
 # Disable ftrace to avoid recursion.
 CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_generic.o = $(CC_FLAGS_FTRACE)
-CFLAGS_REMOVE_generic_report.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_init.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_quarantine.o = $(CC_FLAGS_FTRACE)
 CFLAGS_REMOVE_report.o = $(CC_FLAGS_FTRACE)
-CFLAGS_REMOVE_tags.o = $(CC_FLAGS_FTRACE)
-CFLAGS_REMOVE_tags_report.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_report_generic.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_report_hw_tags.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_report_sw_tags.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_shadow.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_hw_tags.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_sw_tags.o = $(CC_FLAGS_FTRACE)
 
 # Function splitter causes unnecessary splits in __asan_load1/__asan_store1
 # see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63533
@@ -22,13 +25,17 @@ CC_FLAGS_KASAN_RUNTIME += -DDISABLE_BRANCH_PROFILING
 
 CFLAGS_common.o := $(CC_FLAGS_KASAN_RUNTIME)
 CFLAGS_generic.o := $(CC_FLAGS_KASAN_RUNTIME)
-CFLAGS_generic_report.o := $(CC_FLAGS_KASAN_RUNTIME)
 CFLAGS_init.o := $(CC_FLAGS_KASAN_RUNTIME)
 CFLAGS_quarantine.o := $(CC_FLAGS_KASAN_RUNTIME)
 CFLAGS_report.o := $(CC_FLAGS_KASAN_RUNTIME)
-CFLAGS_tags.o := $(CC_FLAGS_KASAN_RUNTIME)
-CFLAGS_tags_report.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_report_generic.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_report_hw_tags.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_report_sw_tags.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_shadow.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_hw_tags.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_sw_tags.o := $(CC_FLAGS_KASAN_RUNTIME)
 
-obj-$(CONFIG_KASAN) := common.o init.o report.o
-obj-$(CONFIG_KASAN_GENERIC) += generic.o generic_report.o quarantine.o
-obj-$(CONFIG_KASAN_SW_TAGS) += tags.o tags_report.o
+obj-$(CONFIG_KASAN) := common.o report.o
+obj-$(CONFIG_KASAN_GENERIC) += init.o generic.o report_generic.o shadow.o quarantine.o
+obj-$(CONFIG_KASAN_HW_TAGS) += hw_tags.o report_hw_tags.o
+obj-$(CONFIG_KASAN_SW_TAGS) += init.o report_sw_tags.o shadow.o sw_tags.o
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 950fd372a07e..b25167664ead 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -1,24 +1,18 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * This file contains common generic and tag-based KASAN code.
+ * This file contains common KASAN code.
  *
  * Copyright (c) 2014 Samsung Electronics Co., Ltd.
  * Author: Andrey Ryabinin <ryabinin.a.a@gmail.com>
  *
  * Some code borrowed from https://github.com/xairy/kasan-prototype by
  *        Andrey Konovalov <andreyknvl@gmail.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
  */
 
 #include <linux/export.h>
 #include <linux/init.h>
 #include <linux/kasan.h>
 #include <linux/kernel.h>
-#include <linux/kmemleak.h>
 #include <linux/linkage.h>
 #include <linux/memblock.h>
 #include <linux/memory.h>
@@ -31,12 +25,8 @@
 #include <linux/stacktrace.h>
 #include <linux/string.h>
 #include <linux/types.h>
-#include <linux/vmalloc.h>
 #include <linux/bug.h>
 
-#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
-
 #include "kasan.h"
 #include "../slab.h"
 
@@ -56,6 +46,7 @@ void kasan_set_track(struct kasan_track *track, gfp_t flags)
 	track->stack = kasan_save_stack(flags);
 }
 
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 void kasan_enable_current(void)
 {
 	current->kasan_depth++;
@@ -65,106 +56,20 @@ void kasan_disable_current(void)
 {
 	current->kasan_depth--;
 }
+#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
 
-bool __kasan_check_read(const volatile void *p, unsigned int size)
-{
-	return check_memory_region((unsigned long)p, size, false, _RET_IP_);
-}
-EXPORT_SYMBOL(__kasan_check_read);
-
-bool __kasan_check_write(const volatile void *p, unsigned int size)
-{
-	return check_memory_region((unsigned long)p, size, true, _RET_IP_);
-}
-EXPORT_SYMBOL(__kasan_check_write);
-
-#undef memset
-void *memset(void *addr, int c, size_t len)
-{
-	if (!check_memory_region((unsigned long)addr, len, true, _RET_IP_))
-		return NULL;
-
-	return __memset(addr, c, len);
-}
-
-#ifdef __HAVE_ARCH_MEMMOVE
-#undef memmove
-void *memmove(void *dest, const void *src, size_t len)
-{
-	if (!check_memory_region((unsigned long)src, len, false, _RET_IP_) ||
-	    !check_memory_region((unsigned long)dest, len, true, _RET_IP_))
-		return NULL;
-
-	return __memmove(dest, src, len);
-}
-#endif
-
-#undef memcpy
-void *memcpy(void *dest, const void *src, size_t len)
+void __kasan_unpoison_range(const void *address, size_t size)
 {
-	if (!check_memory_region((unsigned long)src, len, false, _RET_IP_) ||
-	    !check_memory_region((unsigned long)dest, len, true, _RET_IP_))
-		return NULL;
-
-	return __memcpy(dest, src, len);
-}
-
-/*
- * Poisons the shadow memory for 'size' bytes starting from 'addr'.
- * Memory addresses should be aligned to KASAN_SHADOW_SCALE_SIZE.
- */
-void kasan_poison_shadow(const void *address, size_t size, u8 value)
-{
-	void *shadow_start, *shadow_end;
-
-	/*
-	 * Perform shadow offset calculation based on untagged address, as
-	 * some of the callers (e.g. kasan_poison_object_data) pass tagged
-	 * addresses to this function.
-	 */
-	address = reset_tag(address);
-
-	shadow_start = kasan_mem_to_shadow(address);
-	shadow_end = kasan_mem_to_shadow(address + size);
-
-	__memset(shadow_start, value, shadow_end - shadow_start);
-}
-
-void kasan_unpoison_shadow(const void *address, size_t size)
-{
-	u8 tag = get_tag(address);
-
-	/*
-	 * Perform shadow offset calculation based on untagged address, as
-	 * some of the callers (e.g. kasan_unpoison_object_data) pass tagged
-	 * addresses to this function.
-	 */
-	address = reset_tag(address);
-
-	kasan_poison_shadow(address, size, tag);
-
-	if (size & KASAN_SHADOW_MASK) {
-		u8 *shadow = (u8 *)kasan_mem_to_shadow(address + size);
-
-		if (IS_ENABLED(CONFIG_KASAN_SW_TAGS))
-			*shadow = tag;
-		else
-			*shadow = size & KASAN_SHADOW_MASK;
-	}
-}
-
-static void __kasan_unpoison_stack(struct task_struct *task, const void *sp)
-{
-	void *base = task_stack_page(task);
-	size_t size = sp - base;
-
-	kasan_unpoison_shadow(base, size);
+	unpoison_range(address, size);
 }
 
+#if CONFIG_KASAN_STACK
 /* Unpoison the entire stack for a task. */
 void kasan_unpoison_task_stack(struct task_struct *task)
 {
-	__kasan_unpoison_stack(task, task_stack_page(task) + THREAD_SIZE);
+	void *base = task_stack_page(task);
+
+	unpoison_range(base, THREAD_SIZE);
 }
 
 /* Unpoison the stack for the current task beyond a watermark sp value. */
@@ -177,10 +82,22 @@ asmlinkage void kasan_unpoison_task_stack_below(const void *watermark)
 	 */
 	void *base = (void *)((unsigned long)watermark & ~(THREAD_SIZE - 1));
 
-	kasan_unpoison_shadow(base, watermark - base);
+	unpoison_range(base, watermark - base);
+}
+#endif /* CONFIG_KASAN_STACK */
+
+/*
+ * Only allow cache merging when stack collection is disabled and no metadata
+ * is present.
+ */
+slab_flags_t __kasan_never_merge(void)
+{
+	if (kasan_stack_collection_enabled())
+		return SLAB_KASAN;
+	return 0;
 }
 
-void kasan_alloc_pages(struct page *page, unsigned int order)
+void __kasan_alloc_pages(struct page *page, unsigned int order)
 {
 	u8 tag;
 	unsigned long i;
@@ -191,13 +108,13 @@ void kasan_alloc_pages(struct page *page, unsigned int order)
 	tag = random_tag();
 	for (i = 0; i < (1 << order); i++)
 		page_kasan_tag_set(page + i, tag);
-	kasan_unpoison_shadow(page_address(page), PAGE_SIZE << order);
+	unpoison_range(page_address(page), PAGE_SIZE << order);
 }
 
-void kasan_free_pages(struct page *page, unsigned int order)
+void __kasan_free_pages(struct page *page, unsigned int order)
 {
 	if (likely(!PageHighMem(page)))
-		kasan_poison_shadow(page_address(page),
+		poison_range(page_address(page),
 				PAGE_SIZE << order,
 				KASAN_FREE_PAGE);
 }
@@ -208,9 +125,6 @@ void kasan_free_pages(struct page *page, unsigned int order)
  */
 static inline unsigned int optimal_redzone(unsigned int object_size)
 {
-	if (IS_ENABLED(CONFIG_KASAN_SW_TAGS))
-		return 0;
-
 	return
 		object_size <= 64        - 16   ? 16 :
 		object_size <= 128       - 32   ? 32 :
@@ -221,88 +135,129 @@ static inline unsigned int optimal_redzone(unsigned int object_size)
 		object_size <= (1 << 16) - 1024 ? 1024 : 2048;
 }
 
-void kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
-			slab_flags_t *flags)
+void __kasan_cache_create(struct kmem_cache *cache, unsigned int *size,
+			  slab_flags_t *flags)
 {
-	unsigned int orig_size = *size;
-	unsigned int redzone_size;
-	int redzone_adjust;
+	unsigned int ok_size;
+	unsigned int optimal_size;
 
-	/* Add alloc meta. */
-	cache->kasan_info.alloc_meta_offset = *size;
-	*size += sizeof(struct kasan_alloc_meta);
+	/*
+	 * SLAB_KASAN is used to mark caches as ones that are sanitized by
+	 * KASAN. Currently this flag is used in two places:
+	 * 1. In slab_ksize() when calculating the size of the accessible
+	 *    memory within the object.
+	 * 2. In slab_common.c to prevent merging of sanitized caches.
+	 */
+	*flags |= SLAB_KASAN;
 
-	/* Add free meta. */
-	if (IS_ENABLED(CONFIG_KASAN_GENERIC) &&
-	    (cache->flags & SLAB_TYPESAFE_BY_RCU || cache->ctor ||
-	     cache->object_size < sizeof(struct kasan_free_meta))) {
-		cache->kasan_info.free_meta_offset = *size;
-		*size += sizeof(struct kasan_free_meta);
-	}
+	if (!kasan_stack_collection_enabled())
+		return;
 
-	redzone_size = optimal_redzone(cache->object_size);
-	redzone_adjust = redzone_size -	(*size - cache->object_size);
-	if (redzone_adjust > 0)
-		*size += redzone_adjust;
+	ok_size = *size;
 
-	*size = min_t(unsigned int, KMALLOC_MAX_SIZE,
-			max(*size, cache->object_size + redzone_size));
+	/* Add alloc meta into redzone. */
+	cache->kasan_info.alloc_meta_offset = *size;
+	*size += sizeof(struct kasan_alloc_meta);
 
 	/*
-	 * If the metadata doesn't fit, don't enable KASAN at all.
+	 * If alloc meta doesn't fit, don't add it.
+	 * This can only happen with SLAB, as it has KMALLOC_MAX_SIZE equal
+	 * to KMALLOC_MAX_CACHE_SIZE and doesn't fall back to page_alloc for
+	 * larger sizes.
 	 */
-	if (*size <= cache->kasan_info.alloc_meta_offset ||
-			*size <= cache->kasan_info.free_meta_offset) {
+	if (*size > KMALLOC_MAX_SIZE) {
 		cache->kasan_info.alloc_meta_offset = 0;
-		cache->kasan_info.free_meta_offset = 0;
-		*size = orig_size;
+		*size = ok_size;
+		/* Continue, since free meta might still fit. */
+	}
+
+	/* Only the generic mode uses free meta or flexible redzones. */
+	if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
+		cache->kasan_info.free_meta_offset = KASAN_NO_FREE_META;
 		return;
 	}
 
-	*flags |= SLAB_KASAN;
+	/*
+	 * Add free meta into redzone when it's not possible to store
+	 * it in the object. This is the case when:
+	 * 1. Object is SLAB_TYPESAFE_BY_RCU, which means that it can
+	 *    be touched after it was freed, or
+	 * 2. Object has a constructor, which means it's expected to
+	 *    retain its content until the next allocation, or
+	 * 3. Object is too small.
+	 * Otherwise cache->kasan_info.free_meta_offset = 0 is implied.
+	 */
+	if ((cache->flags & SLAB_TYPESAFE_BY_RCU) || cache->ctor ||
+	    cache->object_size < sizeof(struct kasan_free_meta)) {
+		ok_size = *size;
+
+		cache->kasan_info.free_meta_offset = *size;
+		*size += sizeof(struct kasan_free_meta);
+
+		/* If free meta doesn't fit, don't add it. */
+		if (*size > KMALLOC_MAX_SIZE) {
+			cache->kasan_info.free_meta_offset = KASAN_NO_FREE_META;
+			*size = ok_size;
+		}
+	}
+
+	/* Calculate size with optimal redzone. */
+	optimal_size = cache->object_size + optimal_redzone(cache->object_size);
+	/* Limit it with KMALLOC_MAX_SIZE (relevant for SLAB only). */
+	if (optimal_size > KMALLOC_MAX_SIZE)
+		optimal_size = KMALLOC_MAX_SIZE;
+	/* Use optimal size if the size with added metas is not large enough. */
+	if (*size < optimal_size)
+		*size = optimal_size;
 }
 
-size_t kasan_metadata_size(struct kmem_cache *cache)
+size_t __kasan_metadata_size(struct kmem_cache *cache)
 {
+	if (!kasan_stack_collection_enabled())
+		return 0;
 	return (cache->kasan_info.alloc_meta_offset ?
 		sizeof(struct kasan_alloc_meta) : 0) +
 		(cache->kasan_info.free_meta_offset ?
 		sizeof(struct kasan_free_meta) : 0);
 }
 
-struct kasan_alloc_meta *get_alloc_info(struct kmem_cache *cache,
-					const void *object)
+struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
+					      const void *object)
 {
-	return (void *)object + cache->kasan_info.alloc_meta_offset;
+	if (!cache->kasan_info.alloc_meta_offset)
+		return NULL;
+	return kasan_reset_tag(object) + cache->kasan_info.alloc_meta_offset;
 }
 
-struct kasan_free_meta *get_free_info(struct kmem_cache *cache,
-				      const void *object)
+#ifdef CONFIG_KASAN_GENERIC
+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 *)object + cache->kasan_info.free_meta_offset;
+	if (cache->kasan_info.free_meta_offset == KASAN_NO_FREE_META)
+		return NULL;
+	return kasan_reset_tag(object) + cache->kasan_info.free_meta_offset;
 }
+#endif
 
-void kasan_poison_slab(struct page *page)
+void __kasan_poison_slab(struct page *page)
 {
 	unsigned long i;
 
 	for (i = 0; i < compound_nr(page); i++)
 		page_kasan_tag_reset(page + i);
-	kasan_poison_shadow(page_address(page), page_size(page),
-			KASAN_KMALLOC_REDZONE);
+	poison_range(page_address(page), page_size(page),
+		     KASAN_KMALLOC_REDZONE);
 }
 
-void kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
+void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
 {
-	kasan_unpoison_shadow(object, cache->object_size);
+	unpoison_range(object, cache->object_size);
 }
 
-void kasan_poison_object_data(struct kmem_cache *cache, void *object)
+void __kasan_poison_object_data(struct kmem_cache *cache, void *object)
 {
-	kasan_poison_shadow(object,
-			round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE),
-			KASAN_KMALLOC_REDZONE);
+	poison_range(object, cache->object_size, KASAN_KMALLOC_REDZONE);
 }
 
 /*
@@ -322,6 +277,9 @@ void kasan_poison_object_data(struct kmem_cache *cache, void *object)
 static u8 assign_tag(struct kmem_cache *cache, const void *object,
 			bool init, bool keep_tag)
 {
+	if (IS_ENABLED(CONFIG_KASAN_GENERIC))
+		return 0xff;
+
 	/*
 	 * 1. When an object is kmalloc()'ed, two hooks are called:
 	 *    kasan_slab_alloc() and kasan_kmalloc(). We assign the
@@ -351,50 +309,32 @@ static u8 assign_tag(struct kmem_cache *cache, const void *object,
 #endif
 }
 
-void * __must_check kasan_init_slab_obj(struct kmem_cache *cache,
+void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache,
 						const void *object)
 {
-	struct kasan_alloc_meta *alloc_info;
+	struct kasan_alloc_meta *alloc_meta;
 
-	if (!(cache->flags & SLAB_KASAN))
-		return (void *)object;
-
-	alloc_info = get_alloc_info(cache, object);
-	__memset(alloc_info, 0, sizeof(*alloc_info));
+	if (kasan_stack_collection_enabled()) {
+		alloc_meta = kasan_get_alloc_meta(cache, object);
+		if (alloc_meta)
+			__memset(alloc_meta, 0, sizeof(*alloc_meta));
+	}
 
-	if (IS_ENABLED(CONFIG_KASAN_SW_TAGS))
-		object = set_tag(object,
-				assign_tag(cache, object, true, false));
+	/* Tag is ignored in set_tag() without CONFIG_KASAN_SW/HW_TAGS */
+	object = set_tag(object, assign_tag(cache, object, true, false));
 
 	return (void *)object;
 }
 
-static inline bool shadow_invalid(u8 tag, s8 shadow_byte)
-{
-	if (IS_ENABLED(CONFIG_KASAN_GENERIC))
-		return shadow_byte < 0 ||
-			shadow_byte >= KASAN_SHADOW_SCALE_SIZE;
-
-	/* else CONFIG_KASAN_SW_TAGS: */
-	if ((u8)shadow_byte == KASAN_TAG_INVALID)
-		return true;
-	if ((tag != KASAN_TAG_KERNEL) && (tag != (u8)shadow_byte))
-		return true;
-
-	return false;
-}
-
-static bool __kasan_slab_free(struct kmem_cache *cache, void *object,
+static bool ____kasan_slab_free(struct kmem_cache *cache, void *object,
 			      unsigned long ip, bool quarantine)
 {
-	s8 shadow_byte;
 	u8 tag;
 	void *tagged_object;
-	unsigned long rounded_up_size;
 
 	tag = get_tag(object);
 	tagged_object = object;
-	object = reset_tag(object);
+	object = kasan_reset_tag(object);
 
 	if (unlikely(nearest_obj(cache, virt_to_head_page(object), object) !=
 	    object)) {
@@ -406,37 +346,67 @@ static bool __kasan_slab_free(struct kmem_cache *cache, void *object,
 	if (unlikely(cache->flags & SLAB_TYPESAFE_BY_RCU))
 		return false;
 
-	shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(object));
-	if (shadow_invalid(tag, shadow_byte)) {
+	if (check_invalid_free(tagged_object)) {
 		kasan_report_invalid_free(tagged_object, ip);
 		return true;
 	}
 
-	rounded_up_size = round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE);
-	kasan_poison_shadow(object, rounded_up_size, KASAN_KMALLOC_FREE);
+	poison_range(object, cache->object_size, KASAN_KMALLOC_FREE);
 
-	if ((IS_ENABLED(CONFIG_KASAN_GENERIC) && !quarantine) ||
-			unlikely(!(cache->flags & SLAB_KASAN)))
+	if (!kasan_stack_collection_enabled())
+		return false;
+
+	if ((IS_ENABLED(CONFIG_KASAN_GENERIC) && !quarantine))
 		return false;
 
 	kasan_set_free_info(cache, object, tag);
 
-	quarantine_put(get_free_info(cache, object), cache);
+	return quarantine_put(cache, object);
+}
 
-	return IS_ENABLED(CONFIG_KASAN_GENERIC);
+bool __kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip)
+{
+	return ____kasan_slab_free(cache, object, ip, true);
 }
 
-bool kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip)
+void __kasan_slab_free_mempool(void *ptr, unsigned long ip)
 {
-	return __kasan_slab_free(cache, object, ip, true);
+	struct page *page;
+
+	page = virt_to_head_page(ptr);
+
+	/*
+	 * Even though this function is only called for kmem_cache_alloc and
+	 * kmalloc backed mempool allocations, those allocations can still be
+	 * !PageSlab() when the size provided to kmalloc is larger than
+	 * KMALLOC_MAX_SIZE, and kmalloc falls back onto page_alloc.
+	 */
+	if (unlikely(!PageSlab(page))) {
+		if (ptr != page_address(page)) {
+			kasan_report_invalid_free(ptr, ip);
+			return;
+		}
+		poison_range(ptr, page_size(page), KASAN_FREE_PAGE);
+	} else {
+		____kasan_slab_free(page->slab_cache, ptr, ip, false);
+	}
+}
+
+static void set_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
+{
+	struct kasan_alloc_meta *alloc_meta;
+
+	alloc_meta = kasan_get_alloc_meta(cache, object);
+	if (alloc_meta)
+		kasan_set_track(&alloc_meta->alloc_track, flags);
 }
 
-static void *__kasan_kmalloc(struct kmem_cache *cache, const void *object,
+static void *____kasan_kmalloc(struct kmem_cache *cache, const void *object,
 				size_t size, gfp_t flags, bool keep_tag)
 {
 	unsigned long redzone_start;
 	unsigned long redzone_end;
-	u8 tag = 0xff;
+	u8 tag;
 
 	if (gfpflags_allow_blocking(flags))
 		quarantine_reduce();
@@ -445,38 +415,36 @@ static void *__kasan_kmalloc(struct kmem_cache *cache, const void *object,
 		return NULL;
 
 	redzone_start = round_up((unsigned long)(object + size),
-				KASAN_SHADOW_SCALE_SIZE);
+				KASAN_GRANULE_SIZE);
 	redzone_end = round_up((unsigned long)object + cache->object_size,
-				KASAN_SHADOW_SCALE_SIZE);
-
-	if (IS_ENABLED(CONFIG_KASAN_SW_TAGS))
-		tag = assign_tag(cache, object, false, keep_tag);
+				KASAN_GRANULE_SIZE);
+	tag = assign_tag(cache, object, false, keep_tag);
 
-	/* Tag is ignored in set_tag without CONFIG_KASAN_SW_TAGS */
-	kasan_unpoison_shadow(set_tag(object, tag), size);
-	kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start,
-		KASAN_KMALLOC_REDZONE);
+	/* Tag is ignored in set_tag without CONFIG_KASAN_SW/HW_TAGS */
+	unpoison_range(set_tag(object, tag), size);
+	poison_range((void *)redzone_start, redzone_end - redzone_start,
+		     KASAN_KMALLOC_REDZONE);
 
-	if (cache->flags & SLAB_KASAN)
-		kasan_set_track(&get_alloc_info(cache, object)->alloc_track, flags);
+	if (kasan_stack_collection_enabled())
+		set_alloc_info(cache, (void *)object, flags);
 
 	return set_tag(object, tag);
 }
 
-void * __must_check kasan_slab_alloc(struct kmem_cache *cache, void *object,
-					gfp_t flags)
+void * __must_check __kasan_slab_alloc(struct kmem_cache *cache,
+					void *object, gfp_t flags)
 {
-	return __kasan_kmalloc(cache, object, cache->object_size, flags, false);
+	return ____kasan_kmalloc(cache, object, cache->object_size, flags, false);
 }
 
-void * __must_check kasan_kmalloc(struct kmem_cache *cache, const void *object,
-				size_t size, gfp_t flags)
+void * __must_check __kasan_kmalloc(struct kmem_cache *cache, const void *object,
+					size_t size, gfp_t flags)
 {
-	return __kasan_kmalloc(cache, object, size, flags, true);
+	return ____kasan_kmalloc(cache, object, size, flags, true);
 }
-EXPORT_SYMBOL(kasan_kmalloc);
+EXPORT_SYMBOL(__kasan_kmalloc);
 
-void * __must_check kasan_kmalloc_large(const void *ptr, size_t size,
+void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size,
 						gfp_t flags)
 {
 	struct page *page;
@@ -491,17 +459,17 @@ void * __must_check kasan_kmalloc_large(const void *ptr, size_t size,
 
 	page = virt_to_page(ptr);
 	redzone_start = round_up((unsigned long)(ptr + size),
-				KASAN_SHADOW_SCALE_SIZE);
+				KASAN_GRANULE_SIZE);
 	redzone_end = (unsigned long)ptr + page_size(page);
 
-	kasan_unpoison_shadow(ptr, size);
-	kasan_poison_shadow((void *)redzone_start, redzone_end - redzone_start,
-		KASAN_PAGE_REDZONE);
+	unpoison_range(ptr, size);
+	poison_range((void *)redzone_start, redzone_end - redzone_start,
+		     KASAN_PAGE_REDZONE);
 
 	return (void *)ptr;
 }
 
-void * __must_check kasan_krealloc(const void *object, size_t size, gfp_t flags)
+void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flags)
 {
 	struct page *page;
 
@@ -511,421 +479,15 @@ void * __must_check kasan_krealloc(const void *object, size_t size, gfp_t flags)
 	page = virt_to_head_page(object);
 
 	if (unlikely(!PageSlab(page)))
-		return kasan_kmalloc_large(object, size, flags);
+		return __kasan_kmalloc_large(object, size, flags);
 	else
-		return __kasan_kmalloc(page->slab_cache, object, size,
+		return ____kasan_kmalloc(page->slab_cache, object, size,
 						flags, true);
 }
 
-void kasan_poison_kfree(void *ptr, unsigned long ip)
-{
-	struct page *page;
-
-	page = virt_to_head_page(ptr);
-
-	if (unlikely(!PageSlab(page))) {
-		if (ptr != page_address(page)) {
-			kasan_report_invalid_free(ptr, ip);
-			return;
-		}
-		kasan_poison_shadow(ptr, page_size(page), KASAN_FREE_PAGE);
-	} else {
-		__kasan_slab_free(page->slab_cache, ptr, ip, false);
-	}
-}
-
-void kasan_kfree_large(void *ptr, unsigned long ip)
+void __kasan_kfree_large(void *ptr, unsigned long ip)
 {
 	if (ptr != page_address(virt_to_head_page(ptr)))
 		kasan_report_invalid_free(ptr, ip);
-	/* The object will be poisoned by page_alloc. */
-}
-
-#ifndef CONFIG_KASAN_VMALLOC
-int kasan_module_alloc(void *addr, size_t size)
-{
-	void *ret;
-	size_t scaled_size;
-	size_t shadow_size;
-	unsigned long shadow_start;
-
-	shadow_start = (unsigned long)kasan_mem_to_shadow(addr);
-	scaled_size = (size + KASAN_SHADOW_MASK) >> KASAN_SHADOW_SCALE_SHIFT;
-	shadow_size = round_up(scaled_size, PAGE_SIZE);
-
-	if (WARN_ON(!PAGE_ALIGNED(shadow_start)))
-		return -EINVAL;
-
-	ret = __vmalloc_node_range(shadow_size, 1, shadow_start,
-			shadow_start + shadow_size,
-			GFP_KERNEL,
-			PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE,
-			__builtin_return_address(0));
-
-	if (ret) {
-		__memset(ret, KASAN_SHADOW_INIT, shadow_size);
-		find_vm_area(addr)->flags |= VM_KASAN;
-		kmemleak_ignore(ret);
-		return 0;
-	}
-
-	return -ENOMEM;
-}
-
-void kasan_free_shadow(const struct vm_struct *vm)
-{
-	if (vm->flags & VM_KASAN)
-		vfree(kasan_mem_to_shadow(vm->addr));
-}
-#endif
-
-#ifdef CONFIG_MEMORY_HOTPLUG
-static bool shadow_mapped(unsigned long addr)
-{
-	pgd_t *pgd = pgd_offset_k(addr);
-	p4d_t *p4d;
-	pud_t *pud;
-	pmd_t *pmd;
-	pte_t *pte;
-
-	if (pgd_none(*pgd))
-		return false;
-	p4d = p4d_offset(pgd, addr);
-	if (p4d_none(*p4d))
-		return false;
-	pud = pud_offset(p4d, addr);
-	if (pud_none(*pud))
-		return false;
-
-	/*
-	 * We can't use pud_large() or pud_huge(), the first one is
-	 * arch-specific, the last one depends on HUGETLB_PAGE.  So let's abuse
-	 * pud_bad(), if pud is bad then it's bad because it's huge.
-	 */
-	if (pud_bad(*pud))
-		return true;
-	pmd = pmd_offset(pud, addr);
-	if (pmd_none(*pmd))
-		return false;
-
-	if (pmd_bad(*pmd))
-		return true;
-	pte = pte_offset_kernel(pmd, addr);
-	return !pte_none(*pte);
-}
-
-static int __meminit kasan_mem_notifier(struct notifier_block *nb,
-			unsigned long action, void *data)
-{
-	struct memory_notify *mem_data = data;
-	unsigned long nr_shadow_pages, start_kaddr, shadow_start;
-	unsigned long shadow_end, shadow_size;
-
-	nr_shadow_pages = mem_data->nr_pages >> KASAN_SHADOW_SCALE_SHIFT;
-	start_kaddr = (unsigned long)pfn_to_kaddr(mem_data->start_pfn);
-	shadow_start = (unsigned long)kasan_mem_to_shadow((void *)start_kaddr);
-	shadow_size = nr_shadow_pages << PAGE_SHIFT;
-	shadow_end = shadow_start + shadow_size;
-
-	if (WARN_ON(mem_data->nr_pages % KASAN_SHADOW_SCALE_SIZ