xref: /third_party/mbedtls/tests/src/test_memory.c (revision a8e1175b)
1/**
2 * \file memory.c
3 *
4 * \brief   Helper functions related to testing memory management.
5 */
6
7/*
8 *  Copyright The Mbed TLS Contributors
9 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
10 */
11
12#include <test/helpers.h>
13#include <test/macros.h>
14#include <test/memory.h>
15
16#if defined(MBEDTLS_TEST_MEMORY_CAN_POISON)
17#include <sanitizer/asan_interface.h>
18#include <stdint.h>
19#endif
20
21#if defined(MBEDTLS_TEST_MEMORY_CAN_POISON)
22
23_Thread_local unsigned int mbedtls_test_memory_poisoning_count = 0;
24
25static void align_for_asan(const unsigned char **p_ptr, size_t *p_size)
26{
27    uintptr_t start = (uintptr_t) *p_ptr;
28    uintptr_t end = start + (uintptr_t) *p_size;
29    /* ASan can only poison regions with 8-byte alignment, and only poisons a
30     * region if it's fully within the requested range. We want to poison the
31     * whole requested region and don't mind a few extra bytes. Therefore,
32     * align start down to an 8-byte boundary, and end up to an 8-byte
33     * boundary. */
34    start = start & ~(uintptr_t) 7;
35    end = (end + 7) & ~(uintptr_t) 7;
36    *p_ptr = (const unsigned char *) start;
37    *p_size = end - start;
38}
39
40void mbedtls_test_memory_poison(const unsigned char *ptr, size_t size)
41{
42    if (mbedtls_test_memory_poisoning_count == 0) {
43        return;
44    }
45    if (size == 0) {
46        return;
47    }
48    align_for_asan(&ptr, &size);
49    __asan_poison_memory_region(ptr, size);
50}
51
52void mbedtls_test_memory_unpoison(const unsigned char *ptr, size_t size)
53{
54    if (size == 0) {
55        return;
56    }
57    align_for_asan(&ptr, &size);
58    __asan_unpoison_memory_region(ptr, size);
59}
60#endif /* Memory poisoning */
61