Commit 98f3b56f authored Apr 01, 2020 by Walter Wu Committed by Linus Torvalds Apr 02, 2020

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 <walter-zh.wu@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: kernel test robot <lkp@intel.com>
Link: http://lkml.kernel.org/r/20191112065313.7060-1-walter-zh.wu@mediatek.com


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 8cceeff4

lib/test_kasan.c

+19 −0

Original line number	Diff line number	Diff line
		@@ -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();

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