From 98f3b56fa62a61f1d4d6a5fdd035f0b03be1e93f Mon Sep 17 00:00:00 2001 From: Walter Wu Date: Wed, 1 Apr 2020 21:09:40 -0700 Subject: kasan: add test for invalid size in memmove 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 be detected by KASAN. [walter-zh.wu@mediatek.com: fix -Wstringop-overflow warning] Link: http://lkml.kernel.org/r/20200311134244.13016-1-walter-zh.wu@mediatek.com Signed-off-by: Walter Wu Signed-off-by: Andrew Morton Reviewed-by: Dmitry Vyukov Reviewed-by: Andrey Ryabinin Cc: Alexander Potapenko Cc: kernel test robot Link: http://lkml.kernel.org/r/20191112065313.7060-1-walter-zh.wu@mediatek.com Signed-off-by: Linus Torvalds --- lib/test_kasan.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/lib/test_kasan.c b/lib/test_kasan.c index 3872d250ed2c..e3087d90e00d 100644 --- a/lib/test_kasan.c +++ b/lib/test_kasan.c @@ -285,6 +285,24 @@ 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; + volatile size_t invalid_size = -2; + + 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, invalid_size); + kfree(ptr); +} + static noinline void __init kmalloc_uaf(void) { char *ptr; @@ -799,6 +817,7 @@ 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(); -- cgit v1.2.3