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

From: Vincenzo Frascino
Date: Fri Jan 22 2021 - 15:13:02 EST


KASAN provides an asynchronous mode of execution.

Add reporting functionality for this mode.

Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
---
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