+ kasan-test-disable-kmalloc_memmove_invalid_size-for-hw_tags.patch added to -mm tree

+ kasan-test-disable-kmalloc_memmove_invalid_size-for-hw_tags.patch added to -mm tree

[akpm]

The patch titled
     Subject: kasan: test: disable kmalloc_memmove_invalid_size for HW_TAGS
has been added to the -mm tree.  Its filename is
     kasan-test-disable-kmalloc_memmove_invalid_size-for-hw_tags.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/kasan-test-disable-kmalloc_memmove_invalid_size-for-hw_tags.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/kasan-test-disable-kmalloc_memmove_invalid_size-for-hw_tags.patch

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------------------------------------------------------
From: Andrey Konovalov <andreyknvl@gmail.com>
Subject: kasan: test: disable kmalloc_memmove_invalid_size for HW_TAGS

The HW_TAGS mode doesn't check memmove for negative size.  As a result,
the kmalloc_memmove_invalid_size test corrupts memory, which can result in
a crash.

Disable this test with HW_TAGS KASAN.

Link: https://lkml.kernel.org/r/088733a06ac21eba29aa85b6f769d2abd74f9638.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/test_kasan.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/lib/test_kasan.c~kasan-test-disable-kmalloc_memmove_invalid_size-for-hw_tags
+++ a/lib/test_kasan.c
@@ -501,11 +501,17 @@ static void kmalloc_memmove_invalid_size
 	size_t size = 64;
 	volatile size_t invalid_size = -2;
 
+	/*
+	 * Hardware tag-based mode doesn't check memmove for negative size.
+	 * As a result, this test introduces a side-effect memory corruption,
+	 * which can result in a crash.
+	 */
+	KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_HW_TAGS);
+
 	ptr = kmalloc(size, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
 
 	memset((char *)ptr, 0, 64);
-
 	KUNIT_EXPECT_KASAN_FAIL(test,
 		memmove((char *)ptr, (char *)ptr + 4, invalid_size));
 	kfree(ptr);
_

Patches currently in -mm which might be from andreyknvl@gmail.com are

kasan-test-rework-kmalloc_oob_right.patch
kasan-test-avoid-writing-invalid-memory.patch
kasan-test-avoid-corrupting-memory-via-memset.patch
kasan-test-disable-kmalloc_memmove_invalid_size-for-hw_tags.patch
kasan-test-only-do-kmalloc_uaf_memset-for-generic-mode.patch
kasan-test-clean-up-ksize_uaf.patch
kasan-test-avoid-corrupting-memory-in-copy_user_test.patch
kasan-test-avoid-corrupting-memory-in-kasan_rcu_uaf.patch