From da5a6fba0febbfc90896ce1b2eb75c6d8a88a72d Mon Sep 17 00:00:00 2001 From: Noah Goldstein Date: Wed, 9 Jun 2021 16:17:14 -0400 Subject: String: Add overflow tests for strnlen, memchr, and strncat [BZ #27974] This commit adds tests for a bug in the wide char variant of the functions where the implementation may assume that maxlen for wcsnlen or n for wmemchr/strncat will not overflow when multiplied by sizeof(wchar_t). These tests show the following implementations failing on x86_64: wcsnlen-sse4_1 wcsnlen-avx2 wmemchr-sse2 wmemchr-avx2 strncat would fail as well if it where on a system that prefered either of the wcsnlen implementations that failed as it relies on wcsnlen. Signed-off-by: Noah Goldstein Reviewed-by: H.J. Lu --- string/test-memchr.c | 39 +++++++++++++++++++++++++++++--- string/test-strncat.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++ string/test-strnlen.c | 33 ++++++++++++++++++++++++++++ 3 files changed, 130 insertions(+), 3 deletions(-) (limited to 'string') diff --git a/string/test-memchr.c b/string/test-memchr.c index 665edc3..ce96428 100644 --- a/string/test-memchr.c +++ b/string/test-memchr.c @@ -65,8 +65,8 @@ do_one_test (impl_t *impl, const CHAR *s, int c, size_t n, CHAR *exp_res) CHAR *res = CALL (impl, s, c, n); if (res != exp_res) { - error (0, 0, "Wrong result in function %s %p %p", impl->name, - res, exp_res); + error (0, 0, "Wrong result in function %s (%p, %d, %zu) -> %p != %p", + impl->name, s, c, n, res, exp_res); ret = 1; return; } @@ -91,7 +91,7 @@ do_test (size_t align, size_t pos, size_t len, size_t n, int seek_char) } buf[align + len] = 0; - if (pos < len) + if (pos < MIN(n, len)) { buf[align + pos] = seek_char; buf[align + len] = -seek_char; @@ -108,6 +108,38 @@ do_test (size_t align, size_t pos, size_t len, size_t n, int seek_char) } static void +do_overflow_tests (void) +{ + size_t i, j, len; + const size_t one = 1; + uintptr_t buf_addr = (uintptr_t) buf1; + + for (i = 0; i < 750; ++i) + { + do_test (0, i, 751, SIZE_MAX - i, BIG_CHAR); + do_test (0, i, 751, i - buf_addr, BIG_CHAR); + do_test (0, i, 751, -buf_addr - i, BIG_CHAR); + do_test (0, i, 751, SIZE_MAX - buf_addr - i, BIG_CHAR); + do_test (0, i, 751, SIZE_MAX - buf_addr + i, BIG_CHAR); + + len = 0; + for (j = 8 * sizeof(size_t) - 1; j ; --j) + { + len |= one << j; + do_test (0, i, 751, len - i, BIG_CHAR); + do_test (0, i, 751, len + i, BIG_CHAR); + do_test (0, i, 751, len - buf_addr - i, BIG_CHAR); + do_test (0, i, 751, len - buf_addr + i, BIG_CHAR); + + do_test (0, i, 751, ~len - i, BIG_CHAR); + do_test (0, i, 751, ~len + i, BIG_CHAR); + do_test (0, i, 751, ~len - buf_addr - i, BIG_CHAR); + do_test (0, i, 751, ~len - buf_addr + i, BIG_CHAR); + } + } +} + +static void do_random_tests (void) { size_t i, j, n, align, pos, len; @@ -221,6 +253,7 @@ test_main (void) do_test (page_size / 2 - i, i, i, 1, 0x9B); do_random_tests (); + do_overflow_tests (); return ret; } diff --git a/string/test-strncat.c b/string/test-strncat.c index 2ef917b..37ea26e 100644 --- a/string/test-strncat.c +++ b/string/test-strncat.c @@ -135,6 +135,66 @@ do_test (size_t align1, size_t align2, size_t len1, size_t len2, } static void +do_overflow_tests (void) +{ + size_t i, j, len; + const size_t one = 1; + CHAR *s1, *s2; + uintptr_t s1_addr; + s1 = (CHAR *) buf1; + s2 = (CHAR *) buf2; + s1_addr = (uintptr_t)s1; + for (j = 0; j < 200; ++j) + s2[j] = 32 + 23 * j % (BIG_CHAR - 32); + s2[200] = 0; + for (i = 0; i < 750; ++i) { + for (j = 0; j < i; ++j) + s1[j] = 32 + 23 * j % (BIG_CHAR - 32); + s1[i] = '\0'; + + FOR_EACH_IMPL (impl, 0) + { + s2[200] = '\0'; + do_one_test (impl, s2, s1, SIZE_MAX - i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, i - s1_addr); + s2[200] = '\0'; + do_one_test (impl, s2, s1, -s1_addr - i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, SIZE_MAX - s1_addr - i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, SIZE_MAX - s1_addr + i); + } + + len = 0; + for (j = 8 * sizeof(size_t) - 1; j ; --j) + { + len |= one << j; + FOR_EACH_IMPL (impl, 0) + { + s2[200] = '\0'; + do_one_test (impl, s2, s1, len - i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, len + i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, len - s1_addr - i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, len - s1_addr + i); + + s2[200] = '\0'; + do_one_test (impl, s2, s1, ~len - i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, ~len + i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, ~len - s1_addr - i); + s2[200] = '\0'; + do_one_test (impl, s2, s1, ~len - s1_addr + i); + } + } + } +} + +static void do_random_tests (void) { size_t i, j, n, align1, align2, len1, len2, N; @@ -316,6 +376,7 @@ test_main (void) } do_random_tests (); + do_overflow_tests (); return ret; } diff --git a/string/test-strnlen.c b/string/test-strnlen.c index 920f58e..f53e092 100644 --- a/string/test-strnlen.c +++ b/string/test-strnlen.c @@ -90,6 +90,38 @@ do_test (size_t align, size_t len, size_t maxlen, int max_char) } static void +do_overflow_tests (void) +{ + size_t i, j, len; + const size_t one = 1; + uintptr_t buf_addr = (uintptr_t) buf1; + + for (i = 0; i < 750; ++i) + { + do_test (0, i, SIZE_MAX - i, BIG_CHAR); + do_test (0, i, i - buf_addr, BIG_CHAR); + do_test (0, i, -buf_addr - i, BIG_CHAR); + do_test (0, i, SIZE_MAX - buf_addr - i, BIG_CHAR); + do_test (0, i, SIZE_MAX - buf_addr + i, BIG_CHAR); + + len = 0; + for (j = 8 * sizeof(size_t) - 1; j ; --j) + { + len |= one << j; + do_test (0, i, len - i, BIG_CHAR); + do_test (0, i, len + i, BIG_CHAR); + do_test (0, i, len - buf_addr - i, BIG_CHAR); + do_test (0, i, len - buf_addr + i, BIG_CHAR); + + do_test (0, i, ~len - i, BIG_CHAR); + do_test (0, i, ~len + i, BIG_CHAR); + do_test (0, i, ~len - buf_addr - i, BIG_CHAR); + do_test (0, i, ~len - buf_addr + i, BIG_CHAR); + } + } +} + +static void do_random_tests (void) { size_t i, j, n, align, len; @@ -283,6 +315,7 @@ test_main (void) do_random_tests (); do_page_tests (); do_page_2_tests (); + do_overflow_tests (); return ret; } -- cgit v1.1