Test negative size in memmove in order to verify whether it correctly get KASAN report. Casting negative numbers to size_t would indeed turn up as a 'large' size_t, so it will have out-of-bounds bug and detected by KASAN. Changes in v2: Add some descriptions for clarity the testcase. Signed-off-by: Walter Wu <walter-zh.wu@xxxxxxxxxxxx> Reviewed-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> --- lib/test_kasan.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/lib/test_kasan.c b/lib/test_kasan.c index 49cc4d570a40..06942cf585cc 100644 --- a/lib/test_kasan.c +++ b/lib/test_kasan.c @@ -283,6 +283,23 @@ static noinline void __init kmalloc_oob_in_memset(void) kfree(ptr); } +static noinline void __init kmalloc_memmove_invalid_size(void) +{ + char *ptr; + size_t size = 64; + + pr_info("invalid size in memmove\n"); + ptr = kmalloc(size, GFP_KERNEL); + if (!ptr) { + pr_err("Allocation failed\n"); + return; + } + + memset((char *)ptr, 0, 64); + memmove((char *)ptr, (char *)ptr + 4, -2); + kfree(ptr); +} + static noinline void __init kmalloc_uaf(void) { char *ptr; @@ -773,6 +790,7 @@ static int __init kmalloc_tests_init(void) kmalloc_oob_memset_4(); kmalloc_oob_memset_8(); kmalloc_oob_memset_16(); + kmalloc_memmove_invalid_size(); kmalloc_uaf(); kmalloc_uaf_memset(); kmalloc_uaf2(); -- 2.18.0