[PATCH v7 3/4] kasan: Add report for async mode

[Vincenzo Frascino]

KASAN provides an asynchronous mode of execution.

Add reporting functionality for this mode.

Cc: Dmitry Vyukov <dvyukov at google.com>
Cc: Andrey Ryabinin <aryabinin at virtuozzo.com>
Cc: Alexander Potapenko <glider at google.com>
Cc: Andrey Konovalov <andreyknvl at google.com>
Reviewed-by: Andrey Konovalov <andreyknvl at google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino at arm.com>
---
 include/linux/kasan.h |  2 ++
 mm/kasan/report.c     | 13 +++++++++++++
 2 files changed, 15 insertions(+)

diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index bb862d1f0e15..b0a1d9dfa85c 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -351,6 +351,8 @@ static inline void *kasan_reset_tag(const void *addr)
 bool kasan_report(unsigned long addr, size_t size,
 		bool is_write, unsigned long ip);
 
+void kasan_report_async(void);
+
 #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
 
 static inline void *kasan_reset_tag(const void *addr)
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 234f35a84f19..1390da06a988 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -358,6 +358,19 @@ void kasan_report_invalid_free(void *object, unsigned long ip)
 	end_report(&flags);
 }
 
+#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
+void kasan_report_async(void)
+{
+	unsigned long flags;
+
+	start_report(&flags);
+	pr_err("BUG: KASAN: invalid-access\n");
+	pr_err("Asynchronous mode enabled: no access details available\n");
+	dump_stack();
+	end_report(&flags);
+}
+#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
+
 static void __kasan_report(unsigned long addr, size_t size, bool is_write,
 				unsigned long ip)
 {
-- 
2.30.0