From: Marco Elver <elver@xxxxxxxxxx> Subject: lib/test_kasan: Add test for double-kzfree detection Add a simple test that checks if double-kzfree is being detected correctly. Link: http://lkml.kernel.org/r/20190626142014.141844-4-elver@xxxxxxxxxx Signed-off-by: Marco Elver <elver@xxxxxxxxxx> Reviewed-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/test_kasan.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) --- a/lib/test_kasan.c~lib-test_kasan-add-test-for-double-kzfree-detection +++ a/lib/test_kasan.c @@ -693,6 +693,22 @@ static noinline void __init kasan_bitops kfree(bits); } +static noinline void __init kmalloc_double_kzfree(void) +{ + char *ptr; + size_t size = 16; + + pr_info("double-free (kzfree)\n"); + ptr = kmalloc(size, GFP_KERNEL); + if (!ptr) { + pr_err("Allocation failed\n"); + return; + } + + kzfree(ptr); + kzfree(ptr); +} + static int __init kmalloc_tests_init(void) { /* @@ -735,6 +751,7 @@ static int __init kmalloc_tests_init(voi kasan_memcmp(); kasan_strings(); kasan_bitops(); + kmalloc_double_kzfree(); kasan_restore_multi_shot(multishot); _
