1 files changed, 392 insertions, 223 deletions

diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 3ad9624dcc56..62c01b4527eb 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -9,10 +9,13 @@
  *        Andrey Konovalov <andreyknvl@gmail.com>
  */
 
+#include <kunit/test.h>
+#include <kunit/visibility.h>
 #include <linux/bitops.h>
 #include <linux/ftrace.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
+#include <linux/lockdep.h>
 #include <linux/mm.h>
 #include <linux/printk.h>
 #include <linux/sched.h>
@@ -21,6 +24,7 @@
 #include <linux/stacktrace.h>
 #include <linux/string.h>
 #include <linux/types.h>
+#include <linux/vmalloc.h>
 #include <linux/kasan.h>
 #include <linux/module.h>
 #include <linux/sched/task_stack.h>
@@ -29,8 +33,6 @@
 
 #include <asm/sections.h>
 
-#include <kunit/test.h>
-
 #include "kasan.h"
 #include "../slab.h"
 
@@ -43,6 +45,7 @@ enum kasan_arg_fault {
 	KASAN_ARG_FAULT_DEFAULT,
 	KASAN_ARG_FAULT_REPORT,
 	KASAN_ARG_FAULT_PANIC,
+	KASAN_ARG_FAULT_PANIC_ON_WRITE,
 };
 
 static enum kasan_arg_fault kasan_arg_fault __ro_after_init = KASAN_ARG_FAULT_DEFAULT;
@@ -57,6 +60,8 @@ static int __init early_kasan_fault(char *arg)
 		kasan_arg_fault = KASAN_ARG_FAULT_REPORT;
 	else if (!strcmp(arg, "panic"))
 		kasan_arg_fault = KASAN_ARG_FAULT_PANIC;
+	else if (!strcmp(arg, "panic_on_write"))
+		kasan_arg_fault = KASAN_ARG_FAULT_PANIC_ON_WRITE;
 	else
 		return -EINVAL;
 
@@ -64,172 +69,289 @@ static int __init early_kasan_fault(char *arg)
 }
 early_param("kasan.fault", early_kasan_fault);
 
-bool kasan_save_enable_multi_shot(void)
+static int __init kasan_set_multi_shot(char *str)
+{
+	set_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags);
+	return 1;
+}
+__setup("kasan_multi_shot", kasan_set_multi_shot);
+
+/*
+ * This function is used to check whether KASAN reports are suppressed for
+ * software KASAN modes via kasan_disable/enable_current() critical sections.
+ *
+ * This is done to avoid:
+ * 1. False-positive reports when accessing slab metadata,
+ * 2. Deadlocking when poisoned memory is accessed by the reporting code.
+ *
+ * Hardware Tag-Based KASAN instead relies on:
+ * For #1: Resetting tags via kasan_reset_tag().
+ * For #2: Suppression of tag checks via CPU, see report_suppress_start/end().
+ */
+static bool report_suppressed_sw(void)
+{
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
+	if (current->kasan_depth)
+		return true;
+#endif
+	return false;
+}
+
+static void report_suppress_start(void)
+{
+#ifdef CONFIG_KASAN_HW_TAGS
+	/*
+	 * Disable preemption for the duration of printing a KASAN report, as
+	 * hw_suppress_tag_checks_start() disables checks on the current CPU.
+	 */
+	preempt_disable();
+	hw_suppress_tag_checks_start();
+#else
+	kasan_disable_current();
+#endif
+}
+
+static void report_suppress_stop(void)
+{
+#ifdef CONFIG_KASAN_HW_TAGS
+	hw_suppress_tag_checks_stop();
+	preempt_enable();
+#else
+	kasan_enable_current();
+#endif
+}
+
+/*
+ * Used to avoid reporting more than one KASAN bug unless kasan_multi_shot
+ * is enabled. Note that KASAN tests effectively enable kasan_multi_shot
+ * for their duration.
+ */
+static bool report_enabled(void)
+{
+	if (test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags))
+		return true;
+	return !test_and_set_bit(KASAN_BIT_REPORTED, &kasan_flags);
+}
+
+#if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
+
+VISIBLE_IF_KUNIT bool kasan_save_enable_multi_shot(void)
 {
 	return test_and_set_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags);
 }
-EXPORT_SYMBOL_GPL(kasan_save_enable_multi_shot);
+EXPORT_SYMBOL_IF_KUNIT(kasan_save_enable_multi_shot);
 
-void kasan_restore_multi_shot(bool enabled)
+VISIBLE_IF_KUNIT void kasan_restore_multi_shot(bool enabled)
 {
 	if (!enabled)
 		clear_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags);
 }
-EXPORT_SYMBOL_GPL(kasan_restore_multi_shot);
+EXPORT_SYMBOL_IF_KUNIT(kasan_restore_multi_shot);
 
-static int __init kasan_set_multi_shot(char *str)
+#endif
+
+#if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
+
+/*
+ * Whether the KASAN KUnit test suite is currently being executed.
+ * Updated in kasan_test.c.
+ */
+static bool kasan_kunit_executing;
+
+VISIBLE_IF_KUNIT void kasan_kunit_test_suite_start(void)
 {
-	set_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags);
-	return 1;
+	WRITE_ONCE(kasan_kunit_executing, true);
 }
-__setup("kasan_multi_shot", kasan_set_multi_shot);
+EXPORT_SYMBOL_IF_KUNIT(kasan_kunit_test_suite_start);
 
-static void print_error_description(struct kasan_access_info *info)
+VISIBLE_IF_KUNIT void kasan_kunit_test_suite_end(void)
 {
-	pr_err("BUG: KASAN: %s in %pS\n",
-		kasan_get_bug_type(info), (void *)info->ip);
-	if (info->access_size)
-		pr_err("%s of size %zu at addr %px by task %s/%d\n",
-			info->is_write ? "Write" : "Read", info->access_size,
-			info->access_addr, current->comm, task_pid_nr(current));
-	else
-		pr_err("%s at addr %px by task %s/%d\n",
-			info->is_write ? "Write" : "Read",
-			info->access_addr, current->comm, task_pid_nr(current));
+	WRITE_ONCE(kasan_kunit_executing, false);
 }
+EXPORT_SYMBOL_IF_KUNIT(kasan_kunit_test_suite_end);
+
+static bool kasan_kunit_test_suite_executing(void)
+{
+	return READ_ONCE(kasan_kunit_executing);
+}
+
+#else /* CONFIG_KASAN_KUNIT_TEST */
 
-static DEFINE_SPINLOCK(report_lock);
+static inline bool kasan_kunit_test_suite_executing(void) { return false; }
 
-static void start_report(unsigned long *flags)
+#endif /* CONFIG_KASAN_KUNIT_TEST */
+
+#if IS_ENABLED(CONFIG_KUNIT)
+
+static void fail_non_kasan_kunit_test(void)
 {
-	/*
-	 * Make sure we don't end up in loop.
-	 */
-	kasan_disable_current();
-	spin_lock_irqsave(&report_lock, *flags);
+	struct kunit *test;
+
+	if (kasan_kunit_test_suite_executing())
+		return;
+
+	test = current->kunit_test;
+	if (test)
+		kunit_set_failure(test);
+}
+
+#else /* CONFIG_KUNIT */
+
+static inline void fail_non_kasan_kunit_test(void) { }
+
+#endif /* CONFIG_KUNIT */
+
+static DEFINE_RAW_SPINLOCK(report_lock);
+
+static void start_report(unsigned long *flags, bool sync)
+{
+	fail_non_kasan_kunit_test();
+	/* Respect the /proc/sys/kernel/traceoff_on_warning interface. */
+	disable_trace_on_warning();
+	/* Do not allow LOCKDEP mangling KASAN reports. */
+	lockdep_off();
+	/* Make sure we don't end up in loop. */
+	report_suppress_start();
+	raw_spin_lock_irqsave(&report_lock, *flags);
 	pr_err("==================================================================\n");
 }
 
-static void end_report(unsigned long *flags, unsigned long addr)
+static void end_report(unsigned long *flags, const void *addr, bool is_write)
 {
-	if (!kasan_async_fault_possible())
-		trace_error_report_end(ERROR_DETECTOR_KASAN, addr);
+	if (addr)
+		trace_error_report_end(ERROR_DETECTOR_KASAN,
+				       (unsigned long)addr);
 	pr_err("==================================================================\n");
+	raw_spin_unlock_irqrestore(&report_lock, *flags);
+	if (!test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags))
+		check_panic_on_warn("KASAN");
+	switch (kasan_arg_fault) {
+	case KASAN_ARG_FAULT_DEFAULT:
+	case KASAN_ARG_FAULT_REPORT:
+		break;
+	case KASAN_ARG_FAULT_PANIC:
+		panic("kasan.fault=panic set ...\n");
+		break;
+	case KASAN_ARG_FAULT_PANIC_ON_WRITE:
+		if (is_write)
+			panic("kasan.fault=panic_on_write set ...\n");
+		break;
+	}
 	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
-	spin_unlock_irqrestore(&report_lock, *flags);
-	if (panic_on_warn && !test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags)) {
-		/*
-		 * This thread may hit another WARN() in the panic path.
-		 * Resetting this prevents additional WARN() from panicking the
-		 * system on this thread.  Other threads are blocked by the
-		 * panic_mutex in panic().
-		 */
-		panic_on_warn = 0;
-		panic("panic_on_warn set ...\n");
+	lockdep_on();
+	report_suppress_stop();
+}
+
+static void print_error_description(struct kasan_report_info *info)
+{
+	pr_err("BUG: KASAN: %s in %pS\n", info->bug_type, (void *)info->ip);
+
+	if (info->type != KASAN_REPORT_ACCESS) {
+		pr_err("Free of addr %px by task %s/%d\n",
+			info->access_addr, current->comm, task_pid_nr(current));
+		return;
 	}
-	if (kasan_arg_fault == KASAN_ARG_FAULT_PANIC)
-		panic("kasan.fault=panic set ...\n");
-	kasan_enable_current();
+
+	if (info->access_size)
+		pr_err("%s of size %zu at addr %px by task %s/%d\n",
+			info->is_write ? "Write" : "Read", info->access_size,
+			info->access_addr, current->comm, task_pid_nr(current));
+	else
+		pr_err("%s at addr %px by task %s/%d\n",
+			info->is_write ? "Write" : "Read",
+			info->access_addr, current->comm, task_pid_nr(current));
 }
 
 static void print_track(struct kasan_track *track, const char *prefix)
 {
+#ifdef CONFIG_KASAN_EXTRA_INFO
+	u64 ts_nsec = track->timestamp;
+	unsigned long rem_usec;
+
+	ts_nsec <<= 9;
+	rem_usec = do_div(ts_nsec, NSEC_PER_SEC) / 1000;
+
+	pr_err("%s by task %u on cpu %d at %lu.%06lus:\n",
+			prefix, track->pid, track->cpu,
+			(unsigned long)ts_nsec, rem_usec);
+#else
 	pr_err("%s by task %u:\n", prefix, track->pid);
-	if (track->stack) {
+#endif /* CONFIG_KASAN_EXTRA_INFO */
+	if (track->stack)
 		stack_depot_print(track->stack);
-	} else {
+	else
 		pr_err("(stack is not available)\n");
-	}
 }
 
-struct page *kasan_addr_to_page(const void *addr)
+static inline struct page *addr_to_page(const void *addr)
 {
-	if ((addr >= (void *)PAGE_OFFSET) &&
-			(addr < high_memory))
+	if (virt_addr_valid(addr))
 		return virt_to_head_page(addr);
 	return NULL;
 }
 
-struct slab *kasan_addr_to_slab(const void *addr)
-{
-	if ((addr >= (void *)PAGE_OFFSET) &&
-			(addr < high_memory))
-		return virt_to_slab(addr);
-	return NULL;
-}
-
-static void describe_object_addr(struct kmem_cache *cache, void *object,
-				const void *addr)
+static void describe_object_addr(const void *addr, struct kasan_report_info *info)
 {
 	unsigned long access_addr = (unsigned long)addr;
-	unsigned long object_addr = (unsigned long)object;
-	const char *rel_type;
+	unsigned long object_addr = (unsigned long)info->object;
+	const char *rel_type, *region_state = "";
 	int rel_bytes;
 
 	pr_err("The buggy address belongs to the object at %px\n"
 	       " which belongs to the cache %s of size %d\n",
-		object, cache->name, cache->object_size);
-
-	if (!addr)
-		return;
+		info->object, info->cache->name, info->cache->object_size);
 
 	if (access_addr < object_addr) {
 		rel_type = "to the left";
 		rel_bytes = object_addr - access_addr;
-	} else if (access_addr >= object_addr + cache->object_size) {
+	} else if (access_addr >= object_addr + info->alloc_size) {
 		rel_type = "to the right";
-		rel_bytes = access_addr - (object_addr + cache->object_size);
+		rel_bytes = access_addr - (object_addr + info->alloc_size);
 	} else {
 		rel_type = "inside";
 		rel_bytes = access_addr - object_addr;
 	}
 
+	/*
+	 * Tag-Based modes use the stack ring to infer the bug type, but the
+	 * memory region state description is generated based on the metadata.
+	 * Thus, defining the region state as below can contradict the metadata.
+	 * Fixing this requires further improvements, so only infer the state
+	 * for the Generic mode.
+	 */
+	if (IS_ENABLED(CONFIG_KASAN_GENERIC)) {
+		if (strcmp(info->bug_type, "slab-out-of-bounds") == 0)
+			region_state = "allocated ";
+		else if (strcmp(info->bug_type, "slab-use-after-free") == 0)
+			region_state = "freed ";
+	}
+
 	pr_err("The buggy address is located %d bytes %s of\n"
-	       " %d-byte region [%px, %px)\n",
-		rel_bytes, rel_type, cache->object_size, (void *)object_addr,
-		(void *)(object_addr + cache->object_size));
+	       " %s%zu-byte region [%px, %px)\n",
+	       rel_bytes, rel_type, region_state, info->alloc_size,
+	       (void *)object_addr, (void *)(object_addr + info->alloc_size));
 }
 
-static void describe_object_stacks(struct kmem_cache *cache, void *object,
-					const void *addr, u8 tag)
+static void describe_object_stacks(struct kasan_report_info *info)
 {
-	struct kasan_alloc_meta *alloc_meta;
-	struct kasan_track *free_track;
-
-	alloc_meta = kasan_get_alloc_meta(cache, object);
-	if (alloc_meta) {
-		print_track(&alloc_meta->alloc_track, "Allocated");
+	if (info->alloc_track.stack) {
+		print_track(&info->alloc_track, "Allocated");
 		pr_err("\n");
 	}
 
-	free_track = kasan_get_free_track(cache, object, tag);
-	if (free_track) {
-		print_track(free_track, "Freed");
+	if (info->free_track.stack) {
+		print_track(&info->free_track, "Freed");
 		pr_err("\n");
 	}
 
-#ifdef CONFIG_KASAN_GENERIC
-	if (!alloc_meta)
-		return;
-	if (alloc_meta->aux_stack[0]) {
-		pr_err("Last potentially related work creation:\n");
-		stack_depot_print(alloc_meta->aux_stack[0]);
-		pr_err("\n");
-	}
-	if (alloc_meta->aux_stack[1]) {
-		pr_err("Second to last potentially related work creation:\n");
-		stack_depot_print(alloc_meta->aux_stack[1]);
-		pr_err("\n");
-	}
-#endif
+	kasan_print_aux_stacks(info->cache, info->object);
 }
 
-static void describe_object(struct kmem_cache *cache, void *object,
-				const void *addr, u8 tag)
+static void describe_object(const void *addr, struct kasan_report_info *info)
 {
 	if (kasan_stack_collection_enabled())
-		describe_object_stacks(cache, object, addr, tag);
-	describe_object_addr(cache, object, addr);
+		describe_object_stacks(info);
+	describe_object_addr(addr, info);
 }
 
 static inline bool kernel_or_module_addr(const void *addr)
@@ -248,32 +370,46 @@ static inline bool init_task_stack_addr(const void *addr)
 			sizeof(init_thread_union.stack));
 }
 
-static void print_address_description(void *addr, u8 tag)
+static void print_address_description(void *addr, u8 tag,
+				      struct kasan_report_info *info)
 {
-	struct page *page = kasan_addr_to_page(addr);
+	struct page *page = addr_to_page(addr);
 
 	dump_stack_lvl(KERN_ERR);
 	pr_err("\n");
 
-	if (page && PageSlab(page)) {
-		struct slab *slab = page_slab(page);
-		struct kmem_cache *cache = slab->slab_cache;
-		void *object = nearest_obj(cache, slab,	addr);
-
-		describe_object(cache, object, addr, tag);
+	if (info->cache && info->object) {
+		describe_object(addr, info);
+		pr_err("\n");
 	}
 
 	if (kernel_or_module_addr(addr) && !init_task_stack_addr(addr)) {
 		pr_err("The buggy address belongs to the variable:\n");
 		pr_err(" %pS\n", addr);
+		pr_err("\n");
+	}
+
+	if (object_is_on_stack(addr)) {
+		/*
+		 * Currently, KASAN supports printing frame information only
+		 * for accesses to the task's own stack.
+		 */
+		kasan_print_address_stack_frame(addr);
+		pr_err("\n");
+	}
+
+	if (is_vmalloc_addr(addr)) {
+		pr_err("The buggy address belongs to a");
+		if (!vmalloc_dump_obj(addr))
+			pr_cont(" vmalloc virtual mapping\n");
+		page = vmalloc_to_page(addr);
 	}
 
 	if (page) {
-		pr_err("The buggy address belongs to the page:\n");
+		pr_err("The buggy address belongs to the physical page:\n");
 		dump_page(page, "kasan: bad access detected");
+		pr_err("\n");
 	}
-
-	kasan_print_address_stack_frame(addr);
 }
 
 static bool meta_row_is_guilty(const void *row, const void *addr)
@@ -332,172 +468,205 @@ static void print_memory_metadata(const void *addr)
 	}
 }
 
-static bool report_enabled(void)
+static void print_report(struct kasan_report_info *info)
 {
-#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);
+	void *addr = kasan_reset_tag((void *)info->access_addr);
+	u8 tag = get_tag((void *)info->access_addr);
+
+	print_error_description(info);
+	if (addr_has_metadata(addr))
+		kasan_print_tags(tag, info->first_bad_addr);
+	pr_err("\n");
+
+	if (addr_has_metadata(addr)) {
+		print_address_description(addr, tag, info);
+		print_memory_metadata(info->first_bad_addr);
+	} else {
+		dump_stack_lvl(KERN_ERR);
+	}
 }
 
-#if IS_ENABLED(CONFIG_KUNIT)
-static void kasan_update_kunit_status(struct kunit *cur_test)
+static void complete_report_info(struct kasan_report_info *info)
 {
-	struct kunit_resource *resource;
-	struct kunit_kasan_expectation *kasan_data;
-
-	resource = kunit_find_named_resource(cur_test, "kasan_data");
+	void *addr = kasan_reset_tag((void *)info->access_addr);
+	struct slab *slab;
 
-	if (!resource) {
-		kunit_set_failure(cur_test);
-		return;
+	if (info->type == KASAN_REPORT_ACCESS)
+		info->first_bad_addr = kasan_find_first_bad_addr(
+					(void *)info->access_addr, info->access_size);
+	else
+		info->first_bad_addr = addr;
+
+	slab = kasan_addr_to_slab(addr);
+	if (slab) {
+		info->cache = slab->slab_cache;
+		info->object = nearest_obj(info->cache, slab, addr);
+
+		/* Try to determine allocation size based on the metadata. */
+		info->alloc_size = kasan_get_alloc_size(info->object, info->cache);
+		/* Fallback to the object size if failed. */
+		if (!info->alloc_size)
+			info->alloc_size = info->cache->object_size;
+	} else
+		info->cache = info->object = NULL;
+
+	switch (info->type) {
+	case KASAN_REPORT_INVALID_FREE:
+		info->bug_type = "invalid-free";
+		break;
+	case KASAN_REPORT_DOUBLE_FREE:
+		info->bug_type = "double-free";
+		break;
+	default:
+		/* bug_type filled in by kasan_complete_mode_report_info. */
+		break;
 	}
 
-	kasan_data = (struct kunit_kasan_expectation *)resource->data;
-	WRITE_ONCE(kasan_data->report_found, true);
-	kunit_put_resource(resource);
+	/* Fill in mode-specific report info fields. */
+	kasan_complete_mode_report_info(info);
 }
-#endif /* IS_ENABLED(CONFIG_KUNIT) */
 
-void kasan_report_invalid_free(void *object, unsigned long ip)
+void kasan_report_invalid_free(void *ptr, unsigned long ip, enum kasan_report_type type)
 {
 	unsigned long flags;
-	u8 tag = get_tag(object);
+	struct kasan_report_info info;
 
-	object = kasan_reset_tag(object);
+	/*
+	 * Do not check report_suppressed_sw(), as an invalid-free cannot be
+	 * caused by accessing poisoned memory and thus should not be suppressed
+	 * by kasan_disable/enable_current() critical sections.
+	 *
+	 * Note that for Hardware Tag-Based KASAN, kasan_report_invalid_free()
+	 * is triggered by explicit tag checks and not by the ones performed by
+	 * the CPU. Thus, reporting invalid-free is not suppressed as well.
+	 */
+	if (unlikely(!report_enabled()))
+		return;
 
-#if IS_ENABLED(CONFIG_KUNIT)
-	if (current->kunit_test)
-		kasan_update_kunit_status(current->kunit_test);
-#endif /* IS_ENABLED(CONFIG_KUNIT) */
+	start_report(&flags, true);
 
-	start_report(&flags);
-	pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", (void *)ip);
-	kasan_print_tags(tag, object);
-	pr_err("\n");
-	print_address_description(object, tag);
-	pr_err("\n");
-	print_memory_metadata(object);
-	end_report(&flags, (unsigned long)object);
-}
+	__memset(&info, 0, sizeof(info));
+	info.type = type;
+	info.access_addr = ptr;
+	info.access_size = 0;
+	info.is_write = false;
+	info.ip = ip;
 
-#ifdef CONFIG_KASAN_HW_TAGS
-void kasan_report_async(void)
-{
-	unsigned long flags;
+	complete_report_info(&info);
 
-#if IS_ENABLED(CONFIG_KUNIT)
-	if (current->kunit_test)
-		kasan_update_kunit_status(current->kunit_test);
-#endif /* IS_ENABLED(CONFIG_KUNIT) */
+	print_report(&info);
 
-	start_report(&flags);
-	pr_err("BUG: KASAN: invalid-access\n");
-	pr_err("Asynchronous mode enabled: no access details available\n");
-	pr_err("\n");
-	dump_stack_lvl(KERN_ERR);
-	end_report(&flags, 0);
+	/*
+	 * Invalid free is considered a "write" since the allocator's metadata
+	 * updates involves writes.
+	 */
+	end_report(&flags, ptr, true);
 }
-#endif /* CONFIG_KASAN_HW_TAGS */
 
-static void __kasan_report(unsigned long addr, size_t size, bool is_write,
-				unsigned long ip)
+/*
+ * kasan_report() is the only reporting function that uses
+ * user_access_save/restore(): kasan_report_invalid_free() cannot be called
+ * from a UACCESS region, and kasan_report_async() is not used on x86.
+ */
+bool kasan_report(const void *addr, size_t size, bool is_write,
+			unsigned long ip)
 {
-	struct kasan_access_info info;
-	void *tagged_addr;
-	void *untagged_addr;
-	unsigned long flags;
-
-#if IS_ENABLED(CONFIG_KUNIT)
-	if (current->kunit_test)
-		kasan_update_kunit_status(current->kunit_test);
-#endif /* IS_ENABLED(CONFIG_KUNIT) */
-
-	disable_trace_on_warning();
+	bool ret = true;
+	unsigned long ua_flags = user_access_save();
+	unsigned long irq_flags;
+	struct kasan_report_info info;
+
+	if (unlikely(report_suppressed_sw()) || unlikely(!report_enabled())) {
+		ret = false;
+		goto out;
+	}
 
-	tagged_addr = (void *)addr;
-	untagged_addr = kasan_reset_tag(tagged_addr);
+	start_report(&irq_flags, true);
 
-	info.access_addr = tagged_addr;
-	if (addr_has_metadata(untagged_addr))
-		info.first_bad_addr =
-			kasan_find_first_bad_addr(tagged_addr, size);
-	else
-		info.first_bad_addr = untagged_addr;
+	__memset(&info, 0, sizeof(info));
+	info.type = KASAN_REPORT_ACCESS;
+	info.access_addr = addr;
 	info.access_size = size;
 	info.is_write = is_write;
 	info.ip = ip;
 
-	start_report(&flags);
+	complete_report_info(&info);
 
-	print_error_description(&info);
-	if (addr_has_metadata(untagged_addr))
-		kasan_print_tags(get_tag(tagged_addr), info.first_bad_addr);
-	pr_err("\n");
+	print_report(&info);
 
-	if (addr_has_metadata(untagged_addr)) {
-		print_address_description(untagged_addr, get_tag(tagged_addr));
-		pr_err("\n");
-		print_memory_metadata(info.first_bad_addr);
-	} else {
-		dump_stack_lvl(KERN_ERR);
-	}
+	end_report(&irq_flags, (void *)addr, is_write);
 
-	end_report(&flags, addr);
+out:
+	user_access_restore(ua_flags);
+
+	return ret;
 }
 
-bool kasan_report(unsigned long addr, size_t size, bool is_write,
-			unsigned long ip)
+#ifdef CONFIG_KASAN_HW_TAGS
+void kasan_report_async(void)
 {
-	unsigned long flags = user_access_save();
-	bool ret = false;
-
-	if (likely(report_enabled())) {
-		__kasan_report(addr, size, is_write, ip);
-		ret = true;
-	}
+	unsigned long flags;
 
-	user_access_restore(flags);
+	/*
+	 * Do not check report_suppressed_sw(), as
+	 * kasan_disable/enable_current() critical sections do not affect
+	 * Hardware Tag-Based KASAN.
+	 */
+	if (unlikely(!report_enabled()))
+		return;
 
-	return ret;
+	start_report(&flags, false);
+	pr_err("BUG: KASAN: invalid-access\n");
+	pr_err("Asynchronous fault: no details available\n");
+	pr_err("\n");
+	dump_stack_lvl(KERN_ERR);
+	/*
+	 * Conservatively set is_write=true, because no details are available.
+	 * In this mode, kasan.fault=panic_on_write is like kasan.fault=panic.
+	 */
+	end_report(&flags, NULL, true);
 }
+#endif /* CONFIG_KASAN_HW_TAGS */
 
-#ifdef CONFIG_KASAN_INLINE
+#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
 /*
- * With CONFIG_KASAN_INLINE, accesses to bogus pointers (outside the high
- * canonical half of the address space) cause out-of-bounds shadow memory reads
- * before the actual access. For addresses in the low canonical half of the
- * address space, as well as most non-canonical addresses, that out-of-bounds
- * shadow memory access lands in the non-canonical part of the address space.
- * Help the user figure out what the original bogus pointer was.
+ * With compiler-based KASAN modes, accesses to bogus pointers (outside of the
+ * mapped kernel address space regions) cause faults when KASAN tries to check
+ * the shadow memory before the actual memory access. This results in cryptic
+ * GPF reports, which are hard for users to interpret. This hook helps users to
+ * figure out what the original bogus pointer was.
  */
 void kasan_non_canonical_hook(unsigned long addr)
 {
 	unsigned long orig_addr;
 	const char *bug_type;
 
+	/*
+	 * All addresses that came as a result of the memory-to-shadow mapping
+	 * (even for bogus pointers) must be >= KASAN_SHADOW_OFFSET.
+	 */
 	if (addr < KASAN_SHADOW_OFFSET)
 		return;
 
-	orig_addr = (addr - KASAN_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT;
+	orig_addr = (unsigned long)kasan_shadow_to_mem((void *)addr);
+
 	/*
 	 * For faults near the shadow address for NULL, we can be fairly certain
 	 * that this is a KASAN shadow memory access.
-	 * For faults that correspond to shadow for low canonical addresses, we
-	 * can still be pretty sure - that shadow region is a fairly narrow
-	 * chunk of the non-canonical address space.
-	 * But faults that look like shadow for non-canonical addresses are a
-	 * really large chunk of the address space. In that case, we still
-	 * print the decoded address, but make it clear that this is not
-	 * necessarily what's actually going on.
+	 * For faults that correspond to the shadow for low or high canonical
+	 * addresses, we can still be pretty sure: these shadow regions are a
+	 * fairly narrow chunk of the address space.
+	 * But the shadow for non-canonical addresses is a really large chunk
+	 * of the address space. For this case, we still print the decoded
+	 * address, but make it clear that this is not necessarily what's
+	 * actually going on.
 	 */
 	if (orig_addr < PAGE_SIZE)
 		bug_type = "null-ptr-deref";
 	else if (orig_addr < TASK_SIZE)
 		bug_type = "probably user-memory-access";
+	else if (addr_in_shadow((void *)addr))
+		bug_type = "probably wild-memory-access";
 	else
 		bug_type = "maybe wild-memory-access";
 	pr_alert("KASAN: %s in range [0x%016lx-0x%016lx]\n", bug_type,