kasan: add hardware tag-based mode for arm64

index de92da1b637a..578d34b12a21 100644
@@ -7,11 +7,6 @@
  *
  * Some code borrowed from https://github.com/xairy/kasan-prototype by
  *        Andrey Konovalov <[email protected]>
- *
- * 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>

index 1f45199e819d..d6a386255007 100644
@@ -7,11 +7,6 @@
  *
  * Some code borrowed from https://github.com/xairy/kasan-prototype by
  *        Andrey Konovalov <[email protected]>
- *
- * 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.
- *
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

index a38c7a9e192a..6bb3f66992df 100644
@@ -7,11 +7,6 @@
  *
  * Some code borrowed from https://github.com/xairy/kasan-prototype by
  *        Andrey Konovalov <[email protected]>
- *
- * 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/bitops.h>

index fe6be0be1f76..9ce8cc5b8621 100644
@@ -4,11 +4,6 @@
  *
  * Copyright (c) 2015 Samsung Electronics Co., Ltd.
  * Author: Andrey Ryabinin <[email protected]>
- *
- * 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/memblock.h>

index 4c5375810449..580ff5610fc1 100644
@@ -6,16 +6,6 @@
  * Copyright (C) 2016 Google, Inc.
  *
  * Based on code by Dmitry Chernenkov.
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
  */
 
 #include <linux/gfp.h>

index 00a53f1355ae..d500923abc8b 100644
@@ -7,11 +7,6 @@
  *
  * Some code borrowed from https://github.com/xairy/kasan-prototype by
  *        Andrey Konovalov <[email protected]>
- *
- * 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/bitops.h>

index e02a36a51f42..5c8b08a25715 100644
@@ -4,11 +4,6 @@
  *
  * Copyright (c) 2018 Google, Inc.
  * Author: Andrey Konovalov <[email protected]>
- *
- * 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.
- *
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

index bee43717d6f0..5f183501b871 100644
@@ -7,11 +7,6 @@
  *
  * Some code borrowed from https://github.com/xairy/kasan-prototype by
  *        Andrey Konovalov <[email protected]>
- *
- * 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/bitops.h>

index 30d343b4a40a..59538e795df4 100644
@@ -75,19 +75,6 @@ struct kasan_cache {
 	int free_meta_offset;
 };
 
-/*
- * These functions provide a special case to support backing module
- * allocations with real shadow memory. With KASAN vmalloc, the special
- * case is unnecessary, as the work is handled in the generic case.
- */
-#ifndef CONFIG_KASAN_VMALLOC
-int kasan_module_alloc(void *addr, size_t size);
-void kasan_free_shadow(const struct vm_struct *vm);
-#else
-static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
-static inline void kasan_free_shadow(const struct vm_struct *vm) {}
-#endif
-
 int kasan_add_zero_shadow(void *start, unsigned long size);
 void kasan_remove_zero_shadow(void *start, unsigned long size);
 

@@ -156,9 +143,6 @@ static inline bool kasan_slab_free(struct kmem_cache *s, void *object,
 	return false;
 }
 
-static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
-static inline void kasan_free_shadow(const struct vm_struct *vm) {}
-
 static inline int kasan_add_zero_shadow(void *start, unsigned long size)
 {
 	return 0;

@@ -211,13 +195,16 @@ static inline void *kasan_reset_tag(const void *addr)
 #endif /* CONFIG_KASAN_SW_TAGS */
 
 #ifdef CONFIG_KASAN_VMALLOC
+
 int kasan_populate_vmalloc(unsigned long addr, unsigned long size);
 void kasan_poison_vmalloc(const void *start, unsigned long size);
 void kasan_unpoison_vmalloc(const void *start, unsigned long size);
 void kasan_release_vmalloc(unsigned long start, unsigned long end,
 			   unsigned long free_region_start,
 			   unsigned long free_region_end);
-#else
+
+#else /* CONFIG_KASAN_VMALLOC */
+
 static inline int kasan_populate_vmalloc(unsigned long start,
 					unsigned long size)
 {

@@ -232,7 +219,25 @@ static inline void kasan_release_vmalloc(unsigned long start,
 					 unsigned long end,
 					 unsigned long free_region_start,
 					 unsigned long free_region_end) {}
-#endif
+
+#endif /* CONFIG_KASAN_VMALLOC */
+
+#if defined(CONFIG_KASAN) && !defined(CONFIG_KASAN_VMALLOC)
+
+/*
+ * These functions provide a special case to support backing module
+ * allocations with real shadow memory. With KASAN vmalloc, the special
+ * case is unnecessary, as the work is handled in the generic case.
+ */
+int kasan_module_alloc(void *addr, size_t size);
+void kasan_free_shadow(const struct vm_struct *vm);
+
+#else /* CONFIG_KASAN && !CONFIG_KASAN_VMALLOC */
+
+static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
+static inline void kasan_free_shadow(const struct vm_struct *vm) {}
+
+#endif /* CONFIG_KASAN && !CONFIG_KASAN_VMALLOC */
 
 #ifdef CONFIG_KASAN_INLINE
 void kasan_non_canonical_hook(unsigned long addr);

94 lines not on this page · raw message

index 59538e795df4..26f2ab92e7ca 100644
@@ -11,7 +11,6 @@ struct task_struct;
 
 #ifdef CONFIG_KASAN
 
-#include <linux/pgtable.h>
 #include <asm/kasan.h>
 
 /* kasan_data struct is used in KUnit tests for KASAN expected failures */

@@ -20,6 +19,20 @@ 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 +48,23 @@ 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 +105,6 @@ 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 +170,6 @@ 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 +177,6 @@ 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 +191,6 @@ 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);

index 26f2ab92e7ca..d237051dca58 100644
@@ -71,7 +71,7 @@ extern void kasan_enable_current(void);
 /* Disable reporting bugs for current task */
 extern void kasan_disable_current(void);
 
-void kasan_unpoison_shadow(const void *address, size_t size);
+void kasan_unpoison_range(const void *address, size_t size);
 
 void kasan_unpoison_task_stack(struct task_struct *task);
 

@@ -108,7 +108,7 @@ struct kasan_cache {
 size_t __ksize(const void *);
 static inline void kasan_unpoison_slab(const void *ptr)
 {
-	kasan_unpoison_shadow(ptr, __ksize(ptr));
+	kasan_unpoison_range(ptr, __ksize(ptr));
 }
 size_t kasan_metadata_size(struct kmem_cache *cache);
 

@@ -117,7 +117,7 @@ void kasan_restore_multi_shot(bool enabled);
 
 #else /* CONFIG_KASAN */
 
-static inline void kasan_unpoison_shadow(const void *address, size_t size) {}
+static inline void kasan_unpoison_range(const void *address, size_t size) {}
 
 static inline void kasan_unpoison_task_stack(struct task_struct *task) {}
 

index c2b3828881fb..3ddd78885a5a 100644
@@ -225,8 +225,8 @@ static unsigned long *alloc_thread_stack_node(struct task_struct *tsk, int node)
 		if (!s)
 			continue;
 
-		/* Clear the KASAN shadow of the stack. */
-		kasan_unpoison_shadow(s->addr, THREAD_SIZE);
+		/* Mark stack accessible for KASAN. */
+		kasan_unpoison_range(s->addr, THREAD_SIZE);
 
 		/* Clear stale pointers from reused stack. */
 		memset(s->addr, 0, THREAD_SIZE);

151 lines not on this page · raw message

index d6a386255007..cdc2d8112f3e 100644
@@ -203,11 +203,11 @@ static void register_global(struct kasan_global *global)
 {
 	size_t aligned_size = round_up(global->size, KASAN_SHADOW_SCALE_SIZE);
 
-	kasan_unpoison_shadow(global->beg, global->size);
+	unpoison_range(global->beg, global->size);
 
-	kasan_poison_shadow(global->beg + aligned_size,
-		global->size_with_redzone - aligned_size,
-		KASAN_GLOBAL_REDZONE);
+	poison_range(global->beg + aligned_size,
+		     global->size_with_redzone - aligned_size,
+		     KASAN_GLOBAL_REDZONE);
 }
 
 void __asan_register_globals(struct kasan_global *globals, size_t size)

@@ -286,13 +286,12 @@ void __asan_alloca_poison(unsigned long addr, size_t size)
 
 	WARN_ON(!IS_ALIGNED(addr, KASAN_ALLOCA_REDZONE_SIZE));
 
-	kasan_unpoison_shadow((const void *)(addr + rounded_down_size),
-			      size - rounded_down_size);
-	kasan_poison_shadow(left_redzone, KASAN_ALLOCA_REDZONE_SIZE,
-			KASAN_ALLOCA_LEFT);
-	kasan_poison_shadow(right_redzone,
-			padding_size + KASAN_ALLOCA_REDZONE_SIZE,
-			KASAN_ALLOCA_RIGHT);
+	unpoison_range((const void *)(addr + rounded_down_size),
+		       size - rounded_down_size);
+	poison_range(left_redzone, KASAN_ALLOCA_REDZONE_SIZE,
+		     KASAN_ALLOCA_LEFT);
+	poison_range(right_redzone, padding_size + KASAN_ALLOCA_REDZONE_SIZE,
+		     KASAN_ALLOCA_RIGHT);
 }
 EXPORT_SYMBOL(__asan_alloca_poison);
 

@@ -302,7 +301,7 @@ void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom)
 	if (unlikely(!stack_top || stack_top > stack_bottom))
 		return;
 
-	kasan_unpoison_shadow(stack_top, stack_bottom - stack_top);
+	unpoison_range(stack_top, stack_bottom - stack_top);
 }
 EXPORT_SYMBOL(__asan_allocas_unpoison);
 

index ac499456740f..42ab02c61331 100644
@@ -150,7 +150,8 @@ static inline bool addr_has_shadow(const void *addr)
 	return (addr >= kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
 }
 
-void kasan_poison_shadow(const void *address, size_t size, u8 value);
+void poison_range(const void *address, size_t size, u8 value);
+void unpoison_range(const void *address, size_t size);
 
 /**
  * check_memory_region - Check memory region, and report if invalid access.

index 5c8b08a25715..c0b3f327812b 100644
@@ -153,7 +153,7 @@ EXPORT_SYMBOL(__hwasan_storeN_noabort);
 
 void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size)
 {
-	kasan_poison_shadow((void *)addr, size, tag);
+	poison_range((void *)addr, size, tag);
 }
 EXPORT_SYMBOL(__hwasan_tag_memory);
 

index 479d17b90155..0b5ae1819a8b 100644
@@ -1179,7 +1179,7 @@ size_t ksize(const void *objp)
 	 * We assume that ksize callers could use whole allocated area,
 	 * so we need to unpoison this area.
 	 */
-	kasan_unpoison_shadow(objp, size);
+	kasan_unpoison_range(objp, size);
 	return size;
 }
 EXPORT_SYMBOL(ksize);

index 662f862702fc..2947274cc2d3 100644
@@ -25,7 +25,7 @@
 
 #include "../mm/kasan/kasan.h"
 
-#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_SHADOW_SCALE_SIZE)
+#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_GRANULE_SIZE)
 
 /*
  * We assign some test results to these globals to make sure the tests

index 2d68db6ae67b..fcb991c3aaf8 100644
@@ -15,7 +15,7 @@
 
 #include "../mm/kasan/kasan.h"
 
-#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_SHADOW_SCALE_SIZE)
+#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_GRANULE_SIZE)
 
 static noinline void __init copy_user_test(void)
 {

index 6adbf5891aff..80dd71e88ef8 100644
@@ -107,7 +107,7 @@ void *memcpy(void *dest, const void *src, size_t len)
 
 /*
  * Poisons the shadow memory for 'size' bytes starting from 'addr'.
- * Memory addresses should be aligned to KASAN_SHADOW_SCALE_SIZE.
+ * Memory addresses should be aligned to KASAN_GRANULE_SIZE.
  */
 void poison_range(const void *address, size_t size, u8 value)
 {

@@ -151,13 +151,13 @@ void unpoison_range(const void *address, size_t size)
 
 	poison_range(address, size, tag);
 
-	if (size & KASAN_SHADOW_MASK) {
+	if (size & KASAN_GRANULE_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;
+			*shadow = size & KASAN_GRANULE_MASK;
 	}
 }
 

@@ -314,7 +314,7 @@ void kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
 void kasan_poison_object_data(struct kmem_cache *cache, void *object)
 {
 	poison_range(object,
-			round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE),
+			round_up(cache->object_size, KASAN_GRANULE_SIZE),
 			KASAN_KMALLOC_REDZONE);
 }
 

@@ -386,7 +386,7 @@ 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;
+			shadow_byte >= KASAN_GRANULE_SIZE;
 
 	/* else CONFIG_KASAN_SW_TAGS: */
 	if ((u8)shadow_byte == KASAN_TAG_INVALID)

@@ -428,7 +428,7 @@ static bool __kasan_slab_free(struct kmem_cache *cache, void *object,
 		return true;
 	}
 
-	rounded_up_size = round_up(cache->object_size, KASAN_SHADOW_SCALE_SIZE);
+	rounded_up_size = round_up(cache->object_size, KASAN_GRANULE_SIZE);
 	poison_range(object, rounded_up_size, KASAN_KMALLOC_FREE);
 
 	if ((IS_ENABLED(CONFIG_KASAN_GENERIC) && !quarantine) ||

@@ -464,9 +464,9 @@ static void *__kasan_kmalloc(struct kmem_cache *cache, const void *object,
 		return (void *)object;
 
 	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);
+				KASAN_GRANULE_SIZE);
 
 	if (IS_ENABLED(CONFIG_KASAN_SW_TAGS))
 		tag = assign_tag(cache, object, false, keep_tag);

@@ -510,7 +510,7 @@ 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);
 
 	unpoison_range(ptr, size);

@@ -608,8 +608,8 @@ static int __meminit kasan_mem_notifier(struct notifier_block *nb,
 	shadow_size = nr_shadow_pages << PAGE_SHIFT;
 	shadow_end = shadow_start + shadow_size;
 
-	if (WARN_ON(mem_data->nr_pages % KASAN_SHADOW_SCALE_SIZE) ||
-		WARN_ON(start_kaddr % (KASAN_SHADOW_SCALE_SIZE << PAGE_SHIFT)))
+	if (WARN_ON(mem_data->nr_pages % KASAN_GRANULE_SIZE) ||
+		WARN_ON(start_kaddr % (KASAN_GRANULE_SIZE << PAGE_SHIFT)))
 		return NOTIFY_BAD;
 
 	switch (action) {

@@ -767,7 +767,7 @@ void kasan_poison_vmalloc(const void *start, unsigned long size)
 	if (!is_vmalloc_or_module_addr(start))
 		return;
 
-	size = round_up(size, KASAN_SHADOW_SCALE_SIZE);
+	size = round_up(size, KASAN_GRANULE_SIZE);
 	poison_range(start, size, KASAN_VMALLOC_INVALID);
 }
 

@@ -880,22 +880,22 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end,
 	unsigned long region_start, region_end;
 	unsigned long size;
 
-	region_start = ALIGN(start, PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE);
-	region_end = ALIGN_DOWN(end, PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE);
+	region_start = ALIGN(start, PAGE_SIZE * KASAN_GRANULE_SIZE);
+	region_end = ALIGN_DOWN(end, PAGE_SIZE * KASAN_GRANULE_SIZE);
 
 	free_region_start = ALIGN(free_region_start,
-				  PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE);
+				  PAGE_SIZE * KASAN_GRANULE_SIZE);
 
 	if (start != region_start &&
 	    free_region_start < region_start)
-		region_start -= PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE;
+		region_start -= PAGE_SIZE * KASAN_GRANULE_SIZE;
 
 	free_region_end = ALIGN_DOWN(free_region_end,
-				     PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE);
+				     PAGE_SIZE * KASAN_GRANULE_SIZE);
 
 	if (end != region_end &&
 	    free_region_end > region_end)
-		region_end += PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE;
+		region_end += PAGE_SIZE * KASAN_GRANULE_SIZE;
 
 	shadow_start = kasan_mem_to_shadow((void *)region_start);
 	shadow_end = kasan_mem_to_shadow((void *)region_end);

@@ -921,7 +921,8 @@ int kasan_module_alloc(void *addr, size_t size)
 	unsigned long shadow_start;
 
 	shadow_start = (unsigned long)kasan_mem_to_shadow(addr);
-	scaled_size = (size + KASAN_SHADOW_MASK) >> KASAN_SHADOW_SCALE_SHIFT;
+	scaled_size = (size + KASAN_GRANULE_SIZE - 1) >>
+				KASAN_SHADOW_SCALE_SHIFT;
 	shadow_size = round_up(scaled_size, PAGE_SIZE);
 
 	if (WARN_ON(!PAGE_ALIGNED(shadow_start)))

index cdc2d8112f3e..754217c258a8 100644
@@ -47,7 +47,7 @@ static __always_inline bool memory_is_poisoned_1(unsigned long addr)
 	s8 shadow_value = *(s8 *)kasan_mem_to_shadow((void *)addr);
 
 	if (unlikely(shadow_value)) {
-		s8 last_accessible_byte = addr & KASAN_SHADOW_MASK;
+		s8 last_accessible_byte = addr & KASAN_GRANULE_MASK;
 		return unlikely(last_accessible_byte >= shadow_value);
 	}
 

@@ -63,7 +63,7 @@ static __always_inline bool memory_is_poisoned_2_4_8(unsigned long addr,
 	 * Access crosses 8(shadow size)-byte boundary. Such access maps
 	 * into 2 shadow bytes, so we need to check them both.
 	 */
-	if (unlikely(((addr + size - 1) & KASAN_SHADOW_MASK) < size - 1))
+	if (unlikely(((addr + size - 1) & KASAN_GRANULE_MASK) < size - 1))
 		return *shadow_addr || memory_is_poisoned_1(addr + size - 1);
 
 	return memory_is_poisoned_1(addr + size - 1);

@@ -74,7 +74,7 @@ static __always_inline bool memory_is_poisoned_16(unsigned long addr)
 	u16 *shadow_addr = (u16 *)kasan_mem_to_shadow((void *)addr);
 
 	/* Unaligned 16-bytes access maps into 3 shadow bytes. */
-	if (unlikely(!IS_ALIGNED(addr, KASAN_SHADOW_SCALE_SIZE)))
+	if (unlikely(!IS_ALIGNED(addr, KASAN_GRANULE_SIZE)))
 		return *shadow_addr || memory_is_poisoned_1(addr + 15);
 
 	return *shadow_addr;

@@ -135,7 +135,7 @@ static __always_inline bool memory_is_poisoned_n(unsigned long addr,
 		s8 *last_shadow = (s8 *)kasan_mem_to_shadow((void *)last_byte);
 
 		if (unlikely(ret != (unsigned long)last_shadow ||
-			((long)(last_byte & KASAN_SHADOW_MASK) >= *last_shadow)))
+			((long)(last_byte & KASAN_GRANULE_MASK) >= *last_shadow)))
 			return true;
 	}
 	return false;

@@ -201,7 +201,7 @@ void kasan_cache_shutdown(struct kmem_cache *cache)
 
 static void register_global(struct kasan_global *global)
 {
-	size_t aligned_size = round_up(global->size, KASAN_SHADOW_SCALE_SIZE);
+	size_t aligned_size = round_up(global->size, KASAN_GRANULE_SIZE);
 
 	unpoison_range(global->beg, global->size);
 

@@ -275,10 +275,10 @@ EXPORT_SYMBOL(__asan_handle_no_return);
 /* Emitted by compiler to poison alloca()ed objects. */
 void __asan_alloca_poison(unsigned long addr, size_t size)
 {
-	size_t rounded_up_size = round_up(size, KASAN_SHADOW_SCALE_SIZE);
+	size_t rounded_up_size = round_up(size, KASAN_GRANULE_SIZE);
 	size_t padding_size = round_up(size, KASAN_ALLOCA_REDZONE_SIZE) -
 			rounded_up_size;
-	size_t rounded_down_size = round_down(size, KASAN_SHADOW_SCALE_SIZE);
+	size_t rounded_down_size = round_down(size, KASAN_GRANULE_SIZE);
 
 	const void *left_redzone = (const void *)(addr -
 			KASAN_ALLOCA_REDZONE_SIZE);

index 6bb3f66992df..7d5b9e5c7cfe 100644
@@ -34,7 +34,7 @@ void *find_first_bad_addr(void *addr, size_t size)
 	void *p = addr;
 
 	while (p < addr + size && !(*(u8 *)kasan_mem_to_shadow(p)))
-		p += KASAN_SHADOW_SCALE_SIZE;
+		p += KASAN_GRANULE_SIZE;
 	return p;
 }
 

@@ -46,14 +46,14 @@ static const char *get_shadow_bug_type(struct kasan_access_info *info)
 	shadow_addr = (u8 *)kasan_mem_to_shadow(info->first_bad_addr);
 
 	/*
-	 * If shadow byte value is in [0, KASAN_SHADOW_SCALE_SIZE) we can look
+	 * If shadow byte value is in [0, KASAN_GRANULE_SIZE) we can look
 	 * at the next shadow byte to determine the type of the bad access.
 	 */
-	if (*shadow_addr > 0 && *shadow_addr <= KASAN_SHADOW_SCALE_SIZE - 1)
+	if (*shadow_addr > 0 && *shadow_addr <= KASAN_GRANULE_SIZE - 1)
 		shadow_addr++;
 
 	switch (*shadow_addr) {
-	case 0 ... KASAN_SHADOW_SCALE_SIZE - 1:
+	case 0 ... KASAN_GRANULE_SIZE - 1:
 		/*
 		 * In theory it's still possible to see these shadow values
 		 * due to a data race in the kernel code.

index 9ce8cc5b8621..dfddd6c39fe6 100644
@@ -442,8 +442,8 @@ void kasan_remove_zero_shadow(void *start, unsigned long size)
 	end = addr + (size >> KASAN_SHADOW_SCALE_SHIFT);
 
 	if (WARN_ON((unsigned long)start %
-			(KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE)) ||
-	    WARN_ON(size % (KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE)))
+			(KASAN_GRANULE_SIZE * PAGE_SIZE)) ||
+	    WARN_ON(size % (KASAN_GRANULE_SIZE * PAGE_SIZE)))
 		return;
 
 	for (; addr < end; addr = next) {

@@ -477,8 +477,8 @@ int kasan_add_zero_shadow(void *start, unsigned long size)
 	shadow_end = shadow_start + (size >> KASAN_SHADOW_SCALE_SHIFT);
 
 	if (WARN_ON((unsigned long)start %
-			(KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE)) ||
-	    WARN_ON(size % (KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE)))
+			(KASAN_GRANULE_SIZE * PAGE_SIZE)) ||
+	    WARN_ON(size % (KASAN_GRANULE_SIZE * PAGE_SIZE)))
 		return -EINVAL;
 
 	ret = kasan_populate_early_shadow(shadow_start, shadow_end);

index 42ab02c61331..53b095f56f28 100644
@@ -5,8 +5,8 @@
 #include <linux/kasan.h>
 #include <linux/stackdepot.h>
 
-#define KASAN_SHADOW_SCALE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)
-#define KASAN_SHADOW_MASK       (KASAN_SHADOW_SCALE_SIZE - 1)
+#define KASAN_GRANULE_SIZE	(1UL << KASAN_SHADOW_SCALE_SHIFT)
+#define KASAN_GRANULE_MASK	(KASAN_GRANULE_SIZE - 1)
 
 #define KASAN_TAG_KERNEL	0xFF /* native kernel pointers tag */
 #define KASAN_TAG_INVALID	0xFE /* inaccessible memory tag */

index d500923abc8b..7b8dcb799a78 100644
@@ -314,24 +314,24 @@ static bool __must_check get_address_stack_frame_info(const void *addr,
 		return false;
 
 	aligned_addr = round_down((unsigned long)addr, sizeof(long));
-	mem_ptr = round_down(aligned_addr, KASAN_SHADOW_SCALE_SIZE);
+	mem_ptr = round_down(aligned_addr, KASAN_GRANULE_SIZE);
 	shadow_ptr = kasan_mem_to_shadow((void *)aligned_addr);
 	shadow_bottom = kasan_mem_to_shadow(end_of_stack(current));
 
 	while (shadow_ptr >= shadow_bottom && *shadow_ptr != KASAN_STACK_LEFT) {
 		shadow_ptr--;
-		mem_ptr -= KASAN_SHADOW_SCALE_SIZE;
+		mem_ptr -= KASAN_GRANULE_SIZE;
 	}
 
 	while (shadow_ptr >= shadow_bottom && *shadow_ptr == KASAN_STACK_LEFT) {
 		shadow_ptr--;
-		mem_ptr -= KASAN_SHADOW_SCALE_SIZE;
+		mem_ptr -= KASAN_GRANULE_SIZE;
 	}
 
 	if (shadow_ptr < shadow_bottom)
 		return false;
 
-	frame = (const unsigned long *)(mem_ptr + KASAN_SHADOW_SCALE_SIZE);
+	frame = (const unsigned long *)(mem_ptr + KASAN_GRANULE_SIZE);
 	if (frame[0] != KASAN_CURRENT_STACK_FRAME_MAGIC) {
 		pr_err("KASAN internal error: frame info validation failed; invalid marker: %lu\n",
 		       frame[0]);

@@ -599,6 +599,6 @@ void kasan_non_canonical_hook(unsigned long addr)
 	else
 		bug_type = "maybe wild-memory-access";
 	pr_alert("KASAN: %s in range [0x%016lx-0x%016lx]\n", bug_type,
-		 orig_addr, orig_addr + KASAN_SHADOW_MASK);
+		 orig_addr, orig_addr + KASAN_GRANULE_SIZE - 1);
 }
 #endif

index 5f183501b871..c87d5a343b4e 100644
@@ -76,7 +76,7 @@ void *find_first_bad_addr(void *addr, size_t size)
 	void *end = p + size;
 
 	while (p < end && tag == *(u8 *)kasan_mem_to_shadow(p))
-		p += KASAN_SHADOW_SCALE_SIZE;
+		p += KASAN_GRANULE_SIZE;
 	return p;
 }
 

index dfddd6c39fe6..1a71eaa8c5f9 100644
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * This file contains some kasan initialization code.
+ * This file contains KASAN shadow initialization code.
  *
  * Copyright (c) 2015 Samsung Electronics Co., Ltd.
  * Author: Andrey Ryabinin <[email protected]>

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index 1a71eaa8c5f9..bc0ad208b3a7 100644
@@ -441,9 +441,8 @@ void kasan_remove_zero_shadow(void *start, unsigned long size)
 	addr = (unsigned long)kasan_mem_to_shadow(start);
 	end = addr + (size >> KASAN_SHADOW_SCALE_SHIFT);
 
-	if (WARN_ON((unsigned long)start %
-			(KASAN_GRANULE_SIZE * PAGE_SIZE)) ||
-	    WARN_ON(size % (KASAN_GRANULE_SIZE * PAGE_SIZE)))
+	if (WARN_ON((unsigned long)start % KASAN_MEMORY_PER_SHADOW_PAGE) ||
+	    WARN_ON(size % KASAN_MEMORY_PER_SHADOW_PAGE))
 		return;
 
 	for (; addr < end; addr = next) {

@@ -476,9 +475,8 @@ int kasan_add_zero_shadow(void *start, unsigned long size)
 	shadow_start = kasan_mem_to_shadow(start);
 	shadow_end = shadow_start + (size >> KASAN_SHADOW_SCALE_SHIFT);
 
-	if (WARN_ON((unsigned long)start %
-			(KASAN_GRANULE_SIZE * PAGE_SIZE)) ||
-	    WARN_ON(size % (KASAN_GRANULE_SIZE * PAGE_SIZE)))
+	if (WARN_ON((unsigned long)start % KASAN_MEMORY_PER_SHADOW_PAGE) ||
+	    WARN_ON(size % KASAN_MEMORY_PER_SHADOW_PAGE))
 		return -EINVAL;
 
 	ret = kasan_populate_early_shadow(shadow_start, shadow_end);

index 53b095f56f28..eec88bf28c64 100644
@@ -8,6 +8,8 @@
 #define KASAN_GRANULE_SIZE	(1UL << KASAN_SHADOW_SCALE_SHIFT)
 #define KASAN_GRANULE_MASK	(KASAN_GRANULE_SIZE - 1)
 
+#define KASAN_MEMORY_PER_SHADOW_PAGE	(KASAN_GRANULE_SIZE << PAGE_SHIFT)
+
 #define KASAN_TAG_KERNEL	0xFF /* native kernel pointers tag */
 #define KASAN_TAG_INVALID	0xFE /* inaccessible memory tag */
 #define KASAN_TAG_MAX		0xFD /* maximum value for random tags */

index 4264bfbdca1a..80522d2c447b 100644
@@ -174,7 +174,7 @@ static int __meminit kasan_mem_notifier(struct notifier_block *nb,
 	shadow_end = shadow_start + shadow_size;
 
 	if (WARN_ON(mem_data->nr_pages % KASAN_GRANULE_SIZE) ||
-		WARN_ON(start_kaddr % (KASAN_GRANULE_SIZE << PAGE_SHIFT)))
+		WARN_ON(start_kaddr % KASAN_MEMORY_PER_SHADOW_PAGE))
 		return NOTIFY_BAD;
 
 	switch (action) {

@@ -445,22 +445,20 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end,
 	unsigned long region_start, region_end;
 	unsigned long size;
 
-	region_start = ALIGN(start, PAGE_SIZE * KASAN_GRANULE_SIZE);
-	region_end = ALIGN_DOWN(end, PAGE_SIZE * KASAN_GRANULE_SIZE);
+	region_start = ALIGN(start, KASAN_MEMORY_PER_SHADOW_PAGE);
+	region_end = ALIGN_DOWN(end, KASAN_MEMORY_PER_SHADOW_PAGE);
 
-	free_region_start = ALIGN(free_region_start,
-				  PAGE_SIZE * KASAN_GRANULE_SIZE);
+	free_region_start = ALIGN(free_region_start, KASAN_MEMORY_PER_SHADOW_PAGE);
 
 	if (start != region_start &&
 	    free_region_start < region_start)
-		region_start -= PAGE_SIZE * KASAN_GRANULE_SIZE;
+		region_start -= KASAN_MEMORY_PER_SHADOW_PAGE;
 
-	free_region_end = ALIGN_DOWN(free_region_end,
-				     PAGE_SIZE * KASAN_GRANULE_SIZE);
+	free_region_end = ALIGN_DOWN(free_region_end, KASAN_MEMORY_PER_SHADOW_PAGE);
 
 	if (end != region_end &&
 	    free_region_end > region_end)
-		region_end += PAGE_SIZE * KASAN_GRANULE_SIZE;
+		region_end += KASAN_MEMORY_PER_SHADOW_PAGE;
 
 	shadow_start = kasan_mem_to_shadow((void *)region_start);
 	shadow_end = kasan_mem_to_shadow((void *)region_end);

index 7b8dcb799a78..fff0c7befbfe 100644
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * This file contains common generic and tag-based KASAN error reporting code.
+ * This file contains common KASAN error reporting code.
  *
  * Copyright (c) 2014 Samsung Electronics Co., Ltd.
  * Author: Andrey Ryabinin <[email protected]>

similarity index 100%
rename from mm/kasan/generic_report.c
rename to mm/kasan/report_generic.c

similarity index 100%
rename from mm/kasan/tags_report.c
rename to mm/kasan/report_sw_tags.c

similarity index 100%
rename from mm/kasan/tags.c
rename to mm/kasan/sw_tags.c

index b3ebee6fcfca..ae55570b4d32 100644
@@ -278,25 +278,9 @@ void * __must_check kasan_init_slab_obj(struct kmem_cache *cache,
 	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_GRANULE_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,
 			      unsigned long ip, bool quarantine)
 {
-	s8 shadow_byte;
 	u8 tag;
 	void *tagged_object;
 	unsigned long rounded_up_size;

@@ -318,8 +302,7 @@ 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;
 	}

index 754217c258a8..67642acafe92 100644
@@ -188,6 +188,13 @@ bool check_memory_region(unsigned long addr, size_t size, bool write,
 	return check_memory_region_inline(addr, size, write, ret_ip);
 }
 
+bool check_invalid_free(void *addr)
+{
+	s8 shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(addr));
+
+	return shadow_byte < 0 || shadow_byte >= KASAN_GRANULE_SIZE;
+}
+
 void kasan_cache_shrink(struct kmem_cache *cache)
 {
 	quarantine_remove_cache(cache);

index eec88bf28c64..e5b5f60bc963 100644
@@ -166,6 +166,8 @@ void unpoison_range(const void *address, size_t size);
 bool check_memory_region(unsigned long addr, size_t size, bool write,
 				unsigned long ret_ip);
 
+bool check_invalid_free(void *addr);
+
 void *find_first_bad_addr(void *addr, size_t size);
 const char *get_bug_type(struct kasan_access_info *info);
 

index c0b3f327812b..64540109c461 100644
@@ -121,6 +121,15 @@ bool check_memory_region(unsigned long addr, size_t size, bool write,
 	return true;
 }
 
+bool check_invalid_free(void *addr)
+{
+	u8 tag = get_tag(addr);
+	u8 shadow_byte = READ_ONCE(*(u8 *)kasan_mem_to_shadow(reset_tag(addr)));
+
+	return (shadow_byte == KASAN_TAG_INVALID) ||
+		(tag != KASAN_TAG_KERNEL && tag != shadow_byte);
+}
+
 #define DEFINE_HWASAN_LOAD_STORE(size)					\
 	void __hwasan_load##size##_noabort(unsigned long addr)		\
 	{								\

index e5b5f60bc963..488ca1ff5979 100644
@@ -171,6 +171,12 @@ bool check_invalid_free(void *addr);
 void *find_first_bad_addr(void *addr, size_t size);
 const char *get_bug_type(struct kasan_access_info *info);
 
+#if defined(CONFIG_KASAN_GENERIC) && CONFIG_KASAN_STACK
+void print_address_stack_frame(const void *addr);
+#else
+static inline void print_address_stack_frame(const void *addr) { }
+#endif
+
 bool kasan_report(unsigned long addr, size_t size,
 		bool is_write, unsigned long ip);
 void kasan_report_invalid_free(void *object, unsigned long ip);

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index b0dc4abc3589..f7ea70d02cab 100644
@@ -13,6 +13,12 @@
 #define arch_kasan_get_tag(addr)	__tag_get(addr)
 
 #ifdef CONFIG_KASAN
+void kasan_init(void);
+#else
+static inline void kasan_init(void) { }
+#endif
+
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 
 /*
  * KASAN_SHADOW_START: beginning of the kernel virtual addresses.

@@ -33,12 +39,10 @@
 #define _KASAN_SHADOW_START(va)	(KASAN_SHADOW_END - (1UL << ((va) - KASAN_SHADOW_SCALE_SHIFT)))
 #define KASAN_SHADOW_START      _KASAN_SHADOW_START(vabits_actual)
 
-void kasan_init(void);
 void kasan_copy_shadow(pgd_t *pgdir);
 asmlinkage void kasan_early_init(void);
 
 #else
-static inline void kasan_init(void) { }
 static inline void kasan_copy_shadow(pgd_t *pgdir) { }
 #endif
 

index b24e43d20667..ffeb80d5aa8d 100644
@@ -21,6 +21,8 @@
 #include <asm/sections.h>
 #include <asm/tlbflush.h>
 
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
+
 static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE);
 
 /*

@@ -208,7 +210,7 @@ static void __init clear_pgds(unsigned long start,
 		set_pgd(pgd_offset_k(start), __pgd(0));
 }
 
-void __init kasan_init(void)
+static void __init kasan_init_shadow(void)
 {
 	u64 kimg_shadow_start, kimg_shadow_end;
 	u64 mod_shadow_start, mod_shadow_end;

@@ -269,6 +271,17 @@ void __init kasan_init(void)
 
 	memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE);
 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
+}
+
+#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) */
+
+static inline void __init kasan_init_shadow(void) { }
+
+#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
+
+void __init kasan_init(void)
+{
+	kasan_init_shadow();
 
 	/* At this point kasan is fully initialized. Enable error messages */
 	init_task.kasan_depth = 0;

index ffeb80d5aa8d..5172799f831f 100644
@@ -273,17 +273,22 @@ static void __init kasan_init_shadow(void)
 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
 }
 
+static void __init kasan_init_depth(void)
+{
+	init_task.kasan_depth = 0;
+}
+
 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) */
 
 static inline void __init kasan_init_shadow(void) { }
 
+static inline void __init kasan_init_depth(void) { }
+
 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
 
 void __init kasan_init(void)
 {
 	kasan_init_shadow();
-
-	/* At this point kasan is fully initialized. Enable error messages */
-	init_task.kasan_depth = 0;
+	kasan_init_depth();
 	pr_info("KernelAddressSanitizer initialized\n");
 }

index d237051dca58..58567a672c5c 100644
@@ -51,6 +51,12 @@ static inline void *kasan_mem_to_shadow(const void *addr)
 int kasan_add_zero_shadow(void *start, unsigned long size);
 void kasan_remove_zero_shadow(void *start, unsigned long size);
 
+/* Enable reporting bugs after kasan_disable_current() */
+extern void kasan_enable_current(void);
+
+/* Disable reporting bugs for current task */
+extern void kasan_disable_current(void);
+
 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
 
 static inline int kasan_add_zero_shadow(void *start, unsigned long size)

@@ -61,16 +67,13 @@ static inline void kasan_remove_zero_shadow(void *start,
 					unsigned long size)
 {}
 
+static inline void kasan_enable_current(void) {}
+static inline void kasan_disable_current(void) {}
+
 #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
 
 #ifdef CONFIG_KASAN
 
-/* Enable reporting bugs after kasan_disable_current() */
-extern void kasan_enable_current(void);
-
-/* Disable reporting bugs for current task */
-extern void kasan_disable_current(void);
-
 void kasan_unpoison_range(const void *address, size_t size);
 
 void kasan_unpoison_task_stack(struct task_struct *task);

@@ -121,9 +124,6 @@ static inline void kasan_unpoison_range(const void *address, size_t size) {}
 
 static inline void kasan_unpoison_task_stack(struct task_struct *task) {}
 
-static inline void kasan_enable_current(void) {}
-static inline void kasan_disable_current(void) {}
-
 static inline void kasan_alloc_pages(struct page *page, unsigned int order) {}
 static inline void kasan_free_pages(struct page *page, unsigned int order) {}
 

index e53e2b110128..d440060c9008 100644
@@ -1225,7 +1225,7 @@ struct task_struct {
 	u64				timer_slack_ns;
 	u64				default_timer_slack_ns;
 
-#ifdef CONFIG_KASAN
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 	unsigned int			kasan_depth;
 #endif
 

index a56f0abb63e9..39703b4ef1f1 100644
@@ -176,7 +176,7 @@ struct task_struct init_task
 	.numa_group	= NULL,
 	.numa_faults	= NULL,
 #endif
-#ifdef CONFIG_KASAN
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 	.kasan_depth	= 1,
 #endif
 #ifdef CONFIG_KCSAN

index ae55570b4d32..52fa763d2169 100644
@@ -47,6 +47,7 @@ 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++;

@@ -56,6 +57,7 @@ void kasan_disable_current(void)
 {
 	current->kasan_depth--;
 }
+#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
 
 void kasan_unpoison_range(const void *address, size_t size)
 {

index b18d193f7f58..af9138ea54ad 100644
@@ -292,8 +292,10 @@ static void print_shadow_for_address(const void *addr)
 
 static bool report_enabled(void)
 {
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 	if (current->kasan_depth)
 		return false;
+#endif
 	if (test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags))
 		return true;
 	return !test_and_set_bit(KASAN_BIT_REPORTED, &kasan_flags);

index f7ea70d02cab..0aaf9044cd6a 100644
@@ -12,14 +12,10 @@
 #define arch_kasan_reset_tag(addr)	__tag_reset(addr)
 #define arch_kasan_get_tag(addr)	__tag_get(addr)
 
-#ifdef CONFIG_KASAN
-void kasan_init(void);
-#else
-static inline void kasan_init(void) { }
-#endif
-
 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 
+void kasan_init(void);
+
 /*
  * KASAN_SHADOW_START: beginning of the kernel virtual addresses.
  * KASAN_SHADOW_END: KASAN_SHADOW_START + 1/N of kernel virtual addresses,

@@ -43,6 +39,7 @@ void kasan_copy_shadow(pgd_t *pgdir);
 asmlinkage void kasan_early_init(void);
 
 #else
+static inline void kasan_init(void) { }
 static inline void kasan_copy_shadow(pgd_t *pgdir) { }
 #endif
 

index 5172799f831f..e35ce04beed1 100644
@@ -278,17 +278,14 @@ static void __init kasan_init_depth(void)
 	init_task.kasan_depth = 0;
 }
 
-#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) */
-
-static inline void __init kasan_init_shadow(void) { }
-
-static inline void __init kasan_init_depth(void) { }
-
-#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
-
 void __init kasan_init(void)
 {
 	kasan_init_shadow();
 	kasan_init_depth();
+#if defined(CONFIG_KASAN_GENERIC)
+	/* CONFIG_KASAN_SW_TAGS also requires kasan_init_tags(). */
 	pr_info("KernelAddressSanitizer initialized\n");
+#endif
 }
+
+#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */

index 67642acafe92..da3608187c25 100644
@@ -9,8 +9,6 @@
  *        Andrey Konovalov <[email protected]>
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
 #include <linux/export.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>

index 64540109c461..9445cf4ccdc8 100644
@@ -6,7 +6,7 @@
  * Author: Andrey Konovalov <[email protected]>
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#define pr_fmt(fmt) "kasan: " fmt
 
 #include <linux/export.h>
 #include <linux/interrupt.h>

@@ -41,6 +41,8 @@ void kasan_init_tags(void)
 
 	for_each_possible_cpu(cpu)
 		per_cpu(prng_state, cpu) = (u32)get_cycles();
+
+	pr_info("KernelAddressSanitizer initialized\n");
 }
 
 /*

index 1a57a76e1cc2..a950d5bc1ba5 100644
@@ -358,7 +358,7 @@ void __init __no_sanitize_address setup_arch(char **cmdline_p)
 	smp_build_mpidr_hash();
 
 	/* Init percpu seeds for random tags after cpus are set up. */
-	kasan_init_tags();
+	kasan_init_sw_tags();
 
 #ifdef CONFIG_ARM64_SW_TTBR0_PAN
 	/*

index e35ce04beed1..d8e66c78440e 100644
@@ -283,7 +283,7 @@ void __init kasan_init(void)
 	kasan_init_shadow();
 	kasan_init_depth();
 #if defined(CONFIG_KASAN_GENERIC)
-	/* CONFIG_KASAN_SW_TAGS also requires kasan_init_tags(). */
+	/* CONFIG_KASAN_SW_TAGS also requires kasan_init_sw_tags(). */
 	pr_info("KernelAddressSanitizer initialized\n");
 #endif
 }

index 58567a672c5c..8b8babab852c 100644
@@ -191,7 +191,7 @@ static inline void kasan_record_aux_stack(void *ptr) {}
 
 #ifdef CONFIG_KASAN_SW_TAGS
 
-void kasan_init_tags(void);
+void __init kasan_init_sw_tags(void);
 
 void *kasan_reset_tag(const void *addr);
 

@@ -200,7 +200,7 @@ bool kasan_report(unsigned long addr, size_t size,
 
 #else /* CONFIG_KASAN_SW_TAGS */
 
-static inline void kasan_init_tags(void) { }
+static inline void kasan_init_sw_tags(void) { }
 
 static inline void *kasan_reset_tag(const void *addr)
 {

index 9445cf4ccdc8..7317d5229b2b 100644
@@ -35,7 +35,7 @@
 
 static DEFINE_PER_CPU(u32, prng_state);
 
-void kasan_init_tags(void)
+void __init kasan_init_sw_tags(void)
 {
 	int cpu;
 

index 488ca1ff5979..c79d30c6fcdb 100644
@@ -147,7 +147,7 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
 		<< KASAN_SHADOW_SCALE_SHIFT);
 }
 
-static inline bool addr_has_shadow(const void *addr)
+static inline bool addr_has_metadata(const void *addr)
 {
 	return (addr >= kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
 }

index af9138ea54ad..2990ca34abaf 100644
@@ -361,7 +361,7 @@ static void __kasan_report(unsigned long addr, size_t size, bool is_write,
 	untagged_addr = reset_tag(tagged_addr);
 
 	info.access_addr = tagged_addr;
-	if (addr_has_shadow(untagged_addr))
+	if (addr_has_metadata(untagged_addr))
 		info.first_bad_addr = find_first_bad_addr(tagged_addr, size);
 	else
 		info.first_bad_addr = untagged_addr;

@@ -372,11 +372,11 @@ static void __kasan_report(unsigned long addr, size_t size, bool is_write,
 	start_report(&flags);
 
 	print_error_description(&info);
-	if (addr_has_shadow(untagged_addr))
+	if (addr_has_metadata(untagged_addr))
 		print_tags(get_tag(tagged_addr), info.first_bad_addr);
 	pr_err("\n");
 
-	if (addr_has_shadow(untagged_addr)) {
+	if (addr_has_metadata(untagged_addr)) {
 		print_address_description(untagged_addr, get_tag(tagged_addr));
 		pr_err("\n");
 		print_shadow_for_address(info.first_bad_addr);

index b543a1ed6078..16ed550850e9 100644
@@ -118,7 +118,7 @@ const char *get_bug_type(struct kasan_access_info *info)
 	if (info->access_addr + info->access_size < info->access_addr)
 		return "out-of-bounds";
 
-	if (addr_has_shadow(info->access_addr))
+	if (addr_has_metadata(info->access_addr))
 		return get_shadow_bug_type(info);
 	return get_wild_bug_type(info);
 }

index 2990ca34abaf..5d5733831ad7 100644
@@ -252,7 +252,7 @@ static int shadow_pointer_offset(const void *row, const void *shadow)
 		(shadow - row) / SHADOW_BYTES_PER_BLOCK + 1;
 }
 
-static void print_shadow_for_address(const void *addr)
+static void print_memory_metadata(const void *addr)
 {
 	int i;
 	const void *shadow = kasan_mem_to_shadow(addr);

@@ -338,7 +338,7 @@ void kasan_report_invalid_free(void *object, unsigned long ip)
 	pr_err("\n");
 	print_address_description(object, tag);
 	pr_err("\n");
-	print_shadow_for_address(object);
+	print_memory_metadata(object);
 	end_report(&flags);
 }
 

@@ -379,7 +379,7 @@ static void __kasan_report(unsigned long addr, size_t size, bool is_write,
 	if (addr_has_metadata(untagged_addr)) {
 		print_address_description(untagged_addr, get_tag(tagged_addr));
 		pr_err("\n");
-		print_shadow_for_address(info.first_bad_addr);
+		print_memory_metadata(info.first_bad_addr);
 	} else {
 		dump_stack();
 	}

index 5d5733831ad7..ab28e350bf39 100644
@@ -33,11 +33,11 @@
 #include "kasan.h"
 #include "../slab.h"
 
-/* Shadow layout customization. */
-#define SHADOW_BYTES_PER_BLOCK 1
-#define SHADOW_BLOCKS_PER_ROW 16
-#define SHADOW_BYTES_PER_ROW (SHADOW_BLOCKS_PER_ROW * SHADOW_BYTES_PER_BLOCK)
-#define SHADOW_ROWS_AROUND_ADDR 2
+/* Metadata layout customization. */
+#define META_BYTES_PER_BLOCK 1
+#define META_BLOCKS_PER_ROW 16
+#define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK)
+#define META_ROWS_AROUND_ADDR 2
 
 static unsigned long kasan_flags;
 

@@ -240,7 +240,7 @@ static void print_address_description(void *addr, u8 tag)
 
 static bool row_is_guilty(const void *row, const void *guilty)
 {
-	return (row <= guilty) && (guilty < row + SHADOW_BYTES_PER_ROW);
+	return (row <= guilty) && (guilty < row + META_BYTES_PER_ROW);
 }
 
 static int shadow_pointer_offset(const void *row, const void *shadow)

@@ -249,7 +249,7 @@ static int shadow_pointer_offset(const void *row, const void *shadow)
 	 *    3 + (BITS_PER_LONG/8)*2 chars.
 	 */
 	return 3 + (BITS_PER_LONG/8)*2 + (shadow - row)*2 +
-		(shadow - row) / SHADOW_BYTES_PER_BLOCK + 1;
+		(shadow - row) / META_BYTES_PER_BLOCK + 1;
 }
 
 static void print_memory_metadata(const void *addr)

@@ -259,15 +259,15 @@ static void print_memory_metadata(const void *addr)
 	const void *shadow_row;
 
 	shadow_row = (void *)round_down((unsigned long)shadow,
-					SHADOW_BYTES_PER_ROW)
-		- SHADOW_ROWS_AROUND_ADDR * SHADOW_BYTES_PER_ROW;
+					META_BYTES_PER_ROW)
+		- META_ROWS_AROUND_ADDR * META_BYTES_PER_ROW;
 
 	pr_err("Memory state around the buggy address:\n");
 
-	for (i = -SHADOW_ROWS_AROUND_ADDR; i <= SHADOW_ROWS_AROUND_ADDR; i++) {
+	for (i = -META_ROWS_AROUND_ADDR; i <= META_ROWS_AROUND_ADDR; i++) {
 		const void *kaddr = kasan_shadow_to_mem(shadow_row);
 		char buffer[4 + (BITS_PER_LONG/8)*2];
-		char shadow_buf[SHADOW_BYTES_PER_ROW];
+		char shadow_buf[META_BYTES_PER_ROW];
 
 		snprintf(buffer, sizeof(buffer),
 			(i == 0) ? ">%px: " : " %px: ", kaddr);

@@ -276,17 +276,17 @@ static void print_memory_metadata(const void *addr)
 		 * function, because generic functions may try to
 		 * access kasan mapping for the passed address.
 		 */
-		memcpy(shadow_buf, shadow_row, SHADOW_BYTES_PER_ROW);
+		memcpy(shadow_buf, shadow_row, META_BYTES_PER_ROW);
 		print_hex_dump(KERN_ERR, buffer,
-			DUMP_PREFIX_NONE, SHADOW_BYTES_PER_ROW, 1,
-			shadow_buf, SHADOW_BYTES_PER_ROW, 0);
+			DUMP_PREFIX_NONE, META_BYTES_PER_ROW, 1,
+			shadow_buf, META_BYTES_PER_ROW, 0);
 
 		if (row_is_guilty(shadow_row, shadow))
 			pr_err("%*c\n",
 				shadow_pointer_offset(shadow_row, shadow),
 				'^');
 
-		shadow_row += SHADOW_BYTES_PER_ROW;
+		shadow_row += META_BYTES_PER_ROW;
 	}
 }
 

index c79d30c6fcdb..3b349a6e799d 100644
@@ -58,6 +58,13 @@
 #define KASAN_ABI_VERSION 1
 #endif
 
+/* Metadata layout customization. */
+#define META_BYTES_PER_BLOCK 1
+#define META_BLOCKS_PER_ROW 16
+#define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK)
+#define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE)
+#define META_ROWS_AROUND_ADDR 2
+
 struct kasan_access_info {
 	const void *access_addr;
 	const void *first_bad_addr;

@@ -170,6 +177,7 @@ bool check_invalid_free(void *addr);
 
 void *find_first_bad_addr(void *addr, size_t size);
 const char *get_bug_type(struct kasan_access_info *info);
+void metadata_fetch_row(char *buffer, void *row);
 
 #if defined(CONFIG_KASAN_GENERIC) && CONFIG_KASAN_STACK
 void print_address_stack_frame(const void *addr);

94 lines not on this page · raw message

index 16ed550850e9..8a9c889872da 100644
@@ -123,6 +123,11 @@ const char *get_bug_type(struct kasan_access_info *info)
 	return get_wild_bug_type(info);
 }
 
+void metadata_fetch_row(char *buffer, void *row)
+{
+	memcpy(buffer, kasan_mem_to_shadow(row), META_BYTES_PER_ROW);
+}
+
 #if CONFIG_KASAN_STACK
 static bool __must_check tokenize_frame_descr(const char **frame_descr,
 					      char *token, size_t max_tok_len,

index c87d5a343b4e..add2dfe6169c 100644
@@ -80,6 +80,11 @@ void *find_first_bad_addr(void *addr, size_t size)
 	return p;
 }
 
+void metadata_fetch_row(char *buffer, void *row)
+{
+	memcpy(buffer, kasan_mem_to_shadow(row), META_BYTES_PER_ROW);
+}
+
 void print_tags(u8 addr_tag, const void *addr)
 {
 	u8 *shadow = (u8 *)kasan_mem_to_shadow(addr);

index 22c81f1edda2..971c20ddfed4 100644
@@ -105,6 +105,7 @@
 #define ESR_ELx_FSC		(0x3F)
 #define ESR_ELx_FSC_TYPE	(0x3C)
 #define ESR_ELx_FSC_EXTABT	(0x10)
+#define ESR_ELx_FSC_MTE		(0x11)
 #define ESR_ELx_FSC_SERROR	(0x11)
 #define ESR_ELx_FSC_ACCESS	(0x08)
 #define ESR_ELx_FSC_FAULT	(0x04)

new file mode 100644
index 000000000000..8401ac5840c7
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020 ARM Ltd.
+ */
+#ifndef __ASM_MTE_DEF_H
+#define __ASM_MTE_DEF_H
+
+#define MTE_GRANULE_SIZE	UL(16)
+#define MTE_GRANULE_MASK	(~(MTE_GRANULE_SIZE - 1))
+#define MTE_TAG_SHIFT		56
+#define MTE_TAG_SIZE		4
+#define MTE_TAG_MASK		GENMASK((MTE_TAG_SHIFT + (MTE_TAG_SIZE - 1)), MTE_TAG_SHIFT)
+#define MTE_TAG_MAX		(MTE_TAG_MASK >> MTE_TAG_SHIFT)
+
+#endif /* __ASM_MTE_DEF_H  */

56 lines not on this page · raw message

index 1c99fcadb58c..cf1cd181dcb2 100644
@@ -5,14 +5,16 @@
 #ifndef __ASM_MTE_H
 #define __ASM_MTE_H
 
-#define MTE_GRANULE_SIZE	UL(16)
-#define MTE_GRANULE_MASK	(~(MTE_GRANULE_SIZE - 1))
-#define MTE_TAG_SHIFT		56
-#define MTE_TAG_SIZE		4
+#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>
 #include <linux/page-flags.h>
+#include <linux/types.h>
 
 #include <asm/pgtable-types.h>
 

@@ -45,7 +47,9 @@ long get_mte_ctrl(struct task_struct *task);
 int mte_ptrace_copy_tags(struct task_struct *child, long request,
 			 unsigned long addr, unsigned long data);
 
-#else
+void mte_assign_mem_tag_range(void *addr, size_t size);
+
+#else /* CONFIG_ARM64_MTE */
 
 /* unused if !CONFIG_ARM64_MTE, silence the compiler */
 #define PG_mte_tagged	0

@@ -80,7 +84,11 @@ static inline int mte_ptrace_copy_tags(struct task_struct *child,
 	return -EIO;
 }
 
-#endif
+static inline void mte_assign_mem_tag_range(void *addr, size_t size)
+{
+}
+
+#endif /* CONFIG_ARM64_MTE */
 
 #endif /* __ASSEMBLY__ */
 #endif /* __ASM_MTE_H  */

64 lines not on this page · raw message

index 42003774d261..9c9f47e9f7f4 100644
@@ -371,6 +371,11 @@ 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);

index 8f99c65837fd..86d554ce98b6 100644
@@ -34,6 +34,15 @@ static void mte_sync_page_tags(struct page *page, pte_t *ptep, bool check_swap)
 			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));
 }
 

index 70a71f38b6a9..b5447e53cd73 100644
@@ -23,6 +23,15 @@ 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);
 	}
 }

index c52c1847079c..7c4ef56265ee 100644
@@ -53,6 +53,15 @@ 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;

index 385a189f7d39..d841a560fae7 100644
@@ -200,13 +200,36 @@ do {									\
 				CONFIG_ARM64_PAN));			\
 } while (0)
 
+/*
+ * The Tag Check Flag (TCF) mode for MTE is per EL, hence TCF0
+ * affects EL0 and TCF affects EL1 irrespective of which TTBR is
+ * used.
+ * The kernel accesses TTBR0 usually with LDTR/STTR instructions
+ * when UAO is available, so these would act as EL0 accesses using
+ * TCF0.
+ * However futex.h code uses exclusives which would be executed as
+ * EL1, this can potentially cause a tag check fault even if the
+ * user disables TCF0.
+ *
+ * To address the problem we set the PSTATE.TCO bit in uaccess_enable()
+ * and reset it in uaccess_disable().
+ *
+ * The Tag check override (TCO) bit disables temporarily the tag checking
+ * preventing the issue.
+ */
 static inline void uaccess_disable(void)
 {
+	asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(0),
+				 ARM64_MTE, CONFIG_KASAN_HW_TAGS));
+
 	__uaccess_disable(ARM64_HAS_PAN);
 }
 
 static inline void uaccess_enable(void)
 {
+	asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(1),
+				 ARM64_MTE, CONFIG_KASAN_HW_TAGS));
+
 	__uaccess_enable(ARM64_HAS_PAN);
 }
 

63 lines not on this page · raw message

index 3a70fb1807fd..71ff6c6786ac 100644
@@ -29,6 +29,8 @@ 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);
 
+void mte_enable_kernel(void);
+
 #else /* CONFIG_ARM64_MTE */
 
 static inline u8 mte_get_ptr_tag(void *ptr)

@@ -49,6 +51,10 @@ static inline void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag)
 	return addr;
 }
 
+static inline void mte_enable_kernel(void)
+{
+}
+
 #endif /* CONFIG_ARM64_MTE */
 
 #endif /* __ASSEMBLY__ */

index 86d554ce98b6..7899e165f30a 100644
@@ -129,6 +129,13 @@ void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag)
 	return ptr;
 }
 
+void mte_enable_kernel(void)
+{
+	/* Enable MTE Sync Mode for EL1. */
+	sysreg_clear_set(sctlr_el1, SCTLR_ELx_TCF_MASK, SCTLR_ELx_TCF_SYNC);
+	isb();
+}
+
 static void update_sctlr_el1_tcf0(u64 tcf0)
 {
 	/* ISB required for the kernel uaccess routines */

index fce8cbecd6bc..e8cfc41a92d4 100644
@@ -154,7 +154,7 @@ struct thread_struct {
 #endif
 #ifdef CONFIG_ARM64_MTE
 	u64			sctlr_tcf0;
-	u64			gcr_user_incl;
+	u64			gcr_user_excl;
 #endif
 };
 

index 7899e165f30a..6a7adb986b52 100644
@@ -156,23 +156,22 @@ static void set_sctlr_el1_tcf0(u64 tcf0)
 	preempt_enable();
 }
 
-static void update_gcr_el1_excl(u64 incl)
+static void update_gcr_el1_excl(u64 excl)
 {
-	u64 excl = ~incl & SYS_GCR_EL1_EXCL_MASK;
 
 	/*
-	 * Note that 'incl' is an include mask (controlled by the user via
-	 * prctl()) while GCR_EL1 accepts an exclude mask.
+	 * Note that the mask controlled by the user via prctl() is an
+	 * include while GCR_EL1 accepts an exclude mask.
 	 * No need for ISB since this only affects EL0 currently, implicit
 	 * with ERET.
 	 */
 	sysreg_clear_set_s(SYS_GCR_EL1, SYS_GCR_EL1_EXCL_MASK, excl);
 }
 
-static void set_gcr_el1_excl(u64 incl)
+static void set_gcr_el1_excl(u64 excl)
 {
-	current->thread.gcr_user_incl = incl;
-	update_gcr_el1_excl(incl);
+	current->thread.gcr_user_excl = excl;
+	update_gcr_el1_excl(excl);
 }
 
 void flush_mte_state(void)

@@ -187,7 +186,7 @@ void flush_mte_state(void)
 	/* disable tag checking */
 	set_sctlr_el1_tcf0(SCTLR_EL1_TCF0_NONE);
 	/* reset tag generation mask */
-	set_gcr_el1_excl(0);
+	set_gcr_el1_excl(SYS_GCR_EL1_EXCL_MASK);
 }
 
 void mte_thread_switch(struct task_struct *next)

@@ -198,7 +197,7 @@ void mte_thread_switch(struct task_struct *next)
 	/* avoid expensive SCTLR_EL1 accesses if no change */
 	if (current->thread.sctlr_tcf0 != next->thread.sctlr_tcf0)
 		update_sctlr_el1_tcf0(next->thread.sctlr_tcf0);
-	update_gcr_el1_excl(next->thread.gcr_user_incl);
+	update_gcr_el1_excl(next->thread.gcr_user_excl);
 }
 
 void mte_suspend_exit(void)

@@ -206,13 +205,14 @@ void mte_suspend_exit(void)
 	if (!system_supports_mte())
 		return;
 
-	update_gcr_el1_excl(current->thread.gcr_user_incl);
+	update_gcr_el1_excl(current->thread.gcr_user_excl);
 }
 
 long set_mte_ctrl(struct task_struct *task, unsigned long arg)
 {
 	u64 tcf0;
-	u64 gcr_incl = (arg & PR_MTE_TAG_MASK) >> PR_MTE_TAG_SHIFT;
+	u64 gcr_excl = ~((arg & PR_MTE_TAG_MASK) >> PR_MTE_TAG_SHIFT) &
+		       SYS_GCR_EL1_EXCL_MASK;
 
 	if (!system_supports_mte())
 		return 0;

@@ -233,10 +233,10 @@ long set_mte_ctrl(struct task_struct *task, unsigned long arg)
 
 	if (task != current) {
 		task->thread.sctlr_tcf0 = tcf0;
-		task->thread.gcr_user_incl = gcr_incl;
+		task->thread.gcr_user_excl = gcr_excl;
 	} else {
 		set_sctlr_el1_tcf0(tcf0);
-		set_gcr_el1_excl(gcr_incl);
+		set_gcr_el1_excl(gcr_excl);
 	}
 
 	return 0;

@@ -245,11 +245,12 @@ long set_mte_ctrl(struct task_struct *task, unsigned long arg)
 long get_mte_ctrl(struct task_struct *task)
 {
 	unsigned long ret;
+	u64 incl = ~task->thread.gcr_user_excl & SYS_GCR_EL1_EXCL_MASK;
 
 	if (!system_supports_mte())
 		return 0;
 
-	ret = task->thread.gcr_user_incl << PR_MTE_TAG_SHIFT;
+	ret = incl << PR_MTE_TAG_SHIFT;
 
 	switch (task->thread.sctlr_tcf0) {
 	case SCTLR_EL1_TCF0_NONE:

index 8401ac5840c7..2d73a1612f09 100644
@@ -10,6 +10,5 @@
 #define MTE_TAG_SHIFT		56
 #define MTE_TAG_SIZE		4
 #define MTE_TAG_MASK		GENMASK((MTE_TAG_SHIFT + (MTE_TAG_SIZE - 1)), MTE_TAG_SHIFT)
-#define MTE_TAG_MAX		(MTE_TAG_MASK >> MTE_TAG_SHIFT)
 
 #endif /* __ASM_MTE_DEF_H  */

index 71ff6c6786ac..26349a4b5e2e 100644
@@ -30,6 +30,7 @@ u8 mte_get_random_tag(void);
 void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag);
 
 void mte_enable_kernel(void);
+void mte_init_tags(u64 max_tag);
 
 #else /* CONFIG_ARM64_MTE */
 

@@ -55,6 +56,10 @@ static inline void mte_enable_kernel(void)
 {
 }
 
+static inline void mte_init_tags(u64 max_tag)
+{
+}
+
 #endif /* CONFIG_ARM64_MTE */
 
 #endif /* __ASSEMBLY__ */

index cf1cd181dcb2..d02aff9f493d 100644
@@ -18,6 +18,8 @@
 
 #include <asm/pgtable-types.h>
 
+extern u64 gcr_kernel_excl;
+
 void mte_clear_page_tags(void *addr);
 unsigned long mte_copy_tags_from_user(void *to, const void __user *from,
 				      unsigned long n);

index 7d32fc959b1a..dfe6ed8446ac 100644
@@ -47,6 +47,9 @@ int main(void)
 #ifdef CONFIG_ARM64_PTR_AUTH
   DEFINE(THREAD_KEYS_USER,	offsetof(struct task_struct, thread.keys_user));
   DEFINE(THREAD_KEYS_KERNEL,	offsetof(struct task_struct, thread.keys_kernel));
+#endif
+#ifdef CONFIG_ARM64_MTE
+  DEFINE(THREAD_GCR_EL1_USER,	offsetof(struct task_struct, thread.gcr_user_excl));
 #endif
   BLANK();
   DEFINE(S_X0,			offsetof(struct pt_regs, regs[0]));

index 6a7adb986b52..02d508391ec7 100644
@@ -23,6 +23,8 @@
 #include <asm/ptrace.h>
 #include <asm/sysreg.h>
 
+u64 gcr_kernel_excl __ro_after_init;
+
 static void mte_sync_page_tags(struct page *page, pte_t *ptep, bool check_swap)
 {
 	pte_t old_pte = READ_ONCE(*ptep);

@@ -129,6 +131,26 @@ void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag)
 	return ptr;
 }
 
+void mte_init_tags(u64 max_tag)
+{
+	static bool gcr_kernel_excl_initialized;
+
+	if (!gcr_kernel_excl_initialized) {
+		/*
+		 * The format of the tags in KASAN is 0xFF and in MTE is 0xF.
+		 * This conversion extracts an MTE tag from a KASAN tag.
+		 */
+		u64 incl = GENMASK(FIELD_GET(MTE_TAG_MASK >> MTE_TAG_SHIFT,
+					     max_tag), 0);
+
+		gcr_kernel_excl = ~incl & SYS_GCR_EL1_EXCL_MASK;
+		gcr_kernel_excl_initialized = true;
+	}
+
+	/* Enable the kernel exclude mask for random tags generation. */
+	write_sysreg_s(SYS_GCR_EL1_RRND | gcr_kernel_excl, SYS_GCR_EL1);
+}
+
 void mte_enable_kernel(void)
 {
 	/* Enable MTE Sync Mode for EL1. */

@@ -171,7 +193,11 @@ static void update_gcr_el1_excl(u64 excl)
 static void set_gcr_el1_excl(u64 excl)
 {
 	current->thread.gcr_user_excl = excl;
-	update_gcr_el1_excl(excl);
+
+	/*
+	 * SYS_GCR_EL1 will be set to current->thread.gcr_user_excl value
+	 * by mte_set_user_gcr() in kernel_exit,
+	 */
 }
 
 void flush_mte_state(void)

@@ -197,7 +223,6 @@ void mte_thread_switch(struct task_struct *next)
 	/* avoid expensive SCTLR_EL1 accesses if no change */
 	if (current->thread.sctlr_tcf0 != next->thread.sctlr_tcf0)
 		update_sctlr_el1_tcf0(next->thread.sctlr_tcf0);
-	update_gcr_el1_excl(next->thread.gcr_user_excl);
 }
 
 void mte_suspend_exit(void)

@@ -205,7 +230,7 @@ void mte_suspend_exit(void)
 	if (!system_supports_mte())
 		return;
 
-	update_gcr_el1_excl(current->thread.gcr_user_excl);
+	update_gcr_el1_excl(gcr_kernel_excl);
 }
 
 long set_mte_ctrl(struct task_struct *task, unsigned long arg)

index 42c32e8a9c5d..236aa4b6b2cc 100644
@@ -7659,6 +7659,11 @@ unsigned long free_reserved_area(void *start, void *end, int poison, const char
 		 * alias for the memset().
 		 */
 		direct_map_addr = page_address(page);
+		/*
+		 * Perform a kasan-unchecked memset() since this memory
+		 * has not been initialized.
+		 */
+		direct_map_addr = kasan_reset_tag(direct_map_addr);
 		if ((unsigned int)poison <= 0xFF)
 			memset(direct_map_addr, poison, PAGE_SIZE);
 

index 63d43b5f82f6..77cbbe3625f2 100644
@@ -6,6 +6,7 @@
 #define __ASM_CACHE_H
 
 #include <asm/cputype.h>
+#include <asm/mte-kasan.h>
 
 #define CTR_L1IP_SHIFT		14
 #define CTR_L1IP_MASK		3

@@ -51,6 +52,8 @@
 
 #ifdef CONFIG_KASAN_SW_TAGS
 #define ARCH_SLAB_MINALIGN	(1ULL << KASAN_SHADOW_SCALE_SHIFT)
+#elif defined(CONFIG_KASAN_HW_TAGS)
+#define ARCH_SLAB_MINALIGN	MTE_GRANULE_SIZE
 #endif
 
 #ifndef __ASSEMBLY__

index 556cb2d62b5b..3bc08e6cf82e 100644
@@ -230,6 +230,15 @@ static inline const void *__tag_set(const void *addr, u8 tag)
 	return (const void *)(__addr | __tag_shifted(tag));
 }
 
+#ifdef CONFIG_KASAN_HW_TAGS
+#define arch_enable_tagging()			mte_enable_kernel()
+#define arch_init_tags(max_tag)			mte_init_tags(max_tag)
+#define arch_get_random_tag()			mte_get_random_tag()
+#define arch_get_mem_tag(addr)			mte_get_mem_tag(addr)
+#define arch_set_mem_tag_range(addr, size, tag)	\
+			mte_set_mem_tag_range((addr), (size), (tag))
+#endif /* CONFIG_KASAN_HW_TAGS */
+
 /*
  * Physical vs virtual RAM address space conversion.  These are
  * private definitions which should NOT be used outside memory.h

index 3b349a6e799d..bc4f28156157 100644
@@ -243,6 +243,32 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 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
+
+#ifndef arch_enable_tagging
+#define arch_enable_tagging()
+#endif
+#ifndef arch_init_tags
+#define arch_init_tags(max_tag)
+#endif
+#ifndef arch_get_random_tag
+#define arch_get_random_tag()	(0xFF)
+#endif
+#ifndef arch_get_mem_tag
+#define arch_get_mem_tag(addr)	(0xFF)
+#endif
+#ifndef arch_set_mem_tag_range
+#define arch_set_mem_tag_range(addr, size, tag) ((void *)(addr))
+#endif
+
+#define hw_enable_tagging()			arch_enable_tagging()
+#define hw_init_tags(max_tag)			arch_init_tags(max_tag)
+#define hw_get_random_tag()			arch_get_random_tag()
+#define hw_get_mem_tag(addr)			arch_get_mem_tag(addr)
+#define hw_set_mem_tag_range(addr, size, tag)	arch_set_mem_tag_range((addr), (size), (tag))
+
+#endif /* CONFIG_KASAN_HW_TAGS */
+
 /*
  * Exported functions for interfaces called from assembly or from generated
  * code. Declarations here to avoid warning about missing declarations.

index bc4f28156157..92cb2c16e314 100644
@@ -5,7 +5,13 @@
 #include <linux/kasan.h>
 #include <linux/stackdepot.h>
 
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 #define KASAN_GRANULE_SIZE	(1UL << KASAN_SHADOW_SCALE_SHIFT)
+#else
+#include <asm/mte-kasan.h>
+#define KASAN_GRANULE_SIZE	MTE_GRANULE_SIZE
+#endif
+
 #define KASAN_GRANULE_MASK	(KASAN_GRANULE_SIZE - 1)
 
 #define KASAN_MEMORY_PER_SHADOW_PAGE	(KASAN_GRANULE_SIZE << PAGE_SHIFT)