[PATCH 1/2] kasan: fix invalid-free test crashing the kernel

[Andrey Konovalov]

When an invalid-free is triggered by one of the KASAN tests, the object
doesn't actually get freed. This later leads to a BUG failure in
kmem_cache_destroy that checks that there are no allocated objects in the
cache that is being destroyed. Fix this by calling kmem_cache_free with
the proper object address after the call that triggers invalid-free.

Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
---
 lib/test_kasan.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index 98854a64b014..ec657105edbf 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -567,7 +567,15 @@ static noinline void __init kmem_cache_invalid_free(void)
 		return;
 	}
 
+	/* Trigger invalid free, the object doesn't get freed */
 	kmem_cache_free(cache, p + 1);
+
+	/*
+	 * Properly free the object to prevent the "Objects remaining in
+	 * test_cache on __kmem_cache_shutdown" BUG failure.
+	 */
+	kmem_cache_free(cache, p);
+
 	kmem_cache_destroy(cache);
 }
 
-- 
2.16.2.395.g2e18187dfd-goog