[PATCH v1 1/3] String: Add additional overflow tests for strnlen, memchr, and strncat
Noah Goldstein
goldstein.w.n@gmail.com
Wed Jun 9 20:52:55 GMT 2021
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 <goldstein.w.n@gmail.com>
---
string/test-memchr.c | 39 ++++++++++++++++++++++++---
string/test-strncat.c | 61 +++++++++++++++++++++++++++++++++++++++++++
string/test-strnlen.c | 33 +++++++++++++++++++++++
3 files changed, 130 insertions(+), 3 deletions(-)
diff --git a/string/test-memchr.c b/string/test-memchr.c
index 665edc32af..ce964284aa 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;
@@ -107,6 +107,38 @@ do_test (size_t align, size_t pos, size_t len, size_t n, int seek_char)
do_one_test (impl, (CHAR *) (buf + align), seek_char, n, result);
}
+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)
{
@@ -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 2ef917b820..0ab7541d4e 100644
--- a/string/test-strncat.c
+++ b/string/test-strncat.c
@@ -134,6 +134,66 @@ 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[0] = '\0';
+ do_one_test (impl, s2, s1, SIZE_MAX - i);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, i - s1_addr);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, -s1_addr - i);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, SIZE_MAX - s1_addr - i);
+ s2[0] = '\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[0] = '\0';
+ do_one_test (impl, s2, s1, len - i);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, len + i);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, len - s1_addr - i);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, len - s1_addr + i);
+
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, ~len - i);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, ~len + i);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, ~len - s1_addr - i);
+ s2[0] = '\0';
+ do_one_test (impl, s2, s1, ~len - s1_addr + i);
+ }
+ }
+ }
+}
+
static void
do_random_tests (void)
{
@@ -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 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;
}
--
2.25.1
More information about the Libc-alpha
mailing list