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-strnlen.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'string/test-strnlen.c') diff --git a/string/test-strnlen.c b/string/test-strnlen.c index 920f58e97b..f53e09263f 100644 --- a/string/test-strnlen.c +++ b/string/test-strnlen.c @@ -89,6 +89,38 @@ do_test (size_t align, size_t len, size_t maxlen, int max_char) do_one_test (impl, (CHAR *) (buf + align), maxlen, MIN (len, maxlen)); } +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) { @@ -283,6 +315,7 @@ test_main (void) do_random_tests (); do_page_tests (); do_page_2_tests (); + do_overflow_tests (); return ret; } -- cgit v1.2.3