glibc/string/test-strstr.c
Wilco Dijkstra 83a552b0bb Fix strstr bug with huge needles (bug 23637)
The generic strstr in GLIBC 2.28 fails to match huge needles.  The optimized
AVAILABLE macro reads ahead a large fixed amount to reduce the overhead of
repeatedly checking for the end of the string.  However if the needle length
is larger than this, two_way_long_needle may confuse this as meaning the end
of the string and return NULL.  This is fixed by adding the needle length to
the amount to read ahead.

	[BZ #23637]
	* string/test-strstr.c (pr23637): New function.
	(test_main): Add tests with longer needles.
	* string/strcasestr.c (AVAILABLE): Fix readahead distance.
	* string/strstr.c (AVAILABLE): Likewise.
2018-09-19 16:50:18 +01:00

244 lines
5.5 KiB
C

/* Test and measure strstr functions.
Copyright (C) 2010-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Written by Ulrich Drepper <drepper@redhat.com>, 2010.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#define TEST_MAIN
#define TEST_NAME "strstr"
#include "test-string.h"
#define STRSTR simple_strstr
#define libc_hidden_builtin_def(arg) /* nothing */
#define __strnlen strnlen
#include "strstr.c"
static char *
stupid_strstr (const char *s1, const char *s2)
{
ssize_t s1len = strlen (s1);
ssize_t s2len = strlen (s2);
if (s2len > s1len)
return NULL;
for (ssize_t i = 0; i <= s1len - s2len; ++i)
{
size_t j;
for (j = 0; j < s2len; ++j)
if (s1[i + j] != s2[j])
break;
if (j == s2len)
return (char *) s1 + i;
}
return NULL;
}
typedef char *(*proto_t) (const char *, const char *);
IMPL (stupid_strstr, 0)
IMPL (simple_strstr, 0)
IMPL (strstr, 1)
static int
check_result (impl_t *impl, const char *s1, const char *s2,
char *exp_result)
{
char *result = CALL (impl, s1, s2);
if (result != exp_result)
{
error (0, 0, "Wrong result in function %s %s %s", impl->name,
result, exp_result);
ret = 1;
return -1;
}
return 0;
}
static void
do_one_test (impl_t *impl, const char *s1, const char *s2, char *exp_result)
{
if (check_result (impl, s1, s2, exp_result) < 0)
return;
}
static void
do_test (size_t align1, size_t align2, size_t len1, size_t len2,
int fail)
{
char *s1 = (char *) (buf1 + align1);
char *s2 = (char *) (buf2 + align2);
static const char d[] = "1234567890abcdef";
#define dl (sizeof (d) - 1)
char *ss2 = s2;
for (size_t l = len2; l > 0; l = l > dl ? l - dl : 0)
{
size_t t = l > dl ? dl : l;
ss2 = mempcpy (ss2, d, t);
}
s2[len2] = '\0';
if (fail)
{
char *ss1 = s1;
for (size_t l = len1; l > 0; l = l > dl ? l - dl : 0)
{
size_t t = l > dl ? dl : l;
memcpy (ss1, d, t);
++ss1[len2 > 7 ? 7 : len2 - 1];
ss1 += t;
}
}
else
{
memset (s1, '0', len1);
memcpy (s1 + len1 - len2, s2, len2);
}
s1[len1] = '\0';
FOR_EACH_IMPL (impl, 0)
do_one_test (impl, s1, s2, fail ? NULL : s1 + len1 - len2);
}
static void
check1 (void)
{
const char s1[] =
"F_BD_CE_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_C3_88_20_EF_BF_BD_EF_BF_BD_EF_BF_BD_C3_A7_20_EF_BF_BD";
const char s2[] = "_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD";
char *exp_result;
exp_result = stupid_strstr (s1, s2);
FOR_EACH_IMPL (impl, 0)
check_result (impl, s1, s2, exp_result);
}
static void
check2 (void)
{
const char s1[] = ", enable_static, \0, enable_shared, ";
char *exp_result;
char *s2 = (void *) buf1 + page_size - 18;
strcpy (s2, s1);
exp_result = stupid_strstr (s1, s1 + 18);
FOR_EACH_IMPL (impl, 0)
{
check_result (impl, s1, s1 + 18, exp_result);
check_result (impl, s2, s1 + 18, exp_result);
}
}
#define N 1024
static void
pr23637 (void)
{
char *h = (char*) buf1;
char *n = (char*) buf2;
for (int i = 0; i < N; i++)
{
n[i] = 'x';
h[i] = ' ';
h[i + N] = 'x';
}
n[N] = '\0';
h[N * 2] = '\0';
/* Ensure we don't match at the first 'x'. */
h[0] = 'x';
char *exp_result = stupid_strstr (h, n);
FOR_EACH_IMPL (impl, 0)
check_result (impl, h, n, exp_result);
}
static int
test_main (void)
{
test_init ();
check1 ();
check2 ();
pr23637 ();
printf ("%23s", "");
FOR_EACH_IMPL (impl, 0)
printf ("\t%s", impl->name);
putchar ('\n');
for (size_t klen = 2; klen < 32; ++klen)
for (size_t hlen = 2 * klen; hlen < 16 * klen; hlen += klen)
{
do_test (0, 0, hlen, klen, 0);
do_test (0, 0, hlen, klen, 1);
do_test (0, 3, hlen, klen, 0);
do_test (0, 3, hlen, klen, 1);
do_test (0, 9, hlen, klen, 0);
do_test (0, 9, hlen, klen, 1);
do_test (0, 15, hlen, klen, 0);
do_test (0, 15, hlen, klen, 1);
do_test (3, 0, hlen, klen, 0);
do_test (3, 0, hlen, klen, 1);
do_test (3, 3, hlen, klen, 0);
do_test (3, 3, hlen, klen, 1);
do_test (3, 9, hlen, klen, 0);
do_test (3, 9, hlen, klen, 1);
do_test (3, 15, hlen, klen, 0);
do_test (3, 15, hlen, klen, 1);
do_test (9, 0, hlen, klen, 0);
do_test (9, 0, hlen, klen, 1);
do_test (9, 3, hlen, klen, 0);
do_test (9, 3, hlen, klen, 1);
do_test (9, 9, hlen, klen, 0);
do_test (9, 9, hlen, klen, 1);
do_test (9, 15, hlen, klen, 0);
do_test (9, 15, hlen, klen, 1);
do_test (15, 0, hlen, klen, 0);
do_test (15, 0, hlen, klen, 1);
do_test (15, 3, hlen, klen, 0);
do_test (15, 3, hlen, klen, 1);
do_test (15, 9, hlen, klen, 0);
do_test (15, 9, hlen, klen, 1);
do_test (15, 15, hlen, klen, 0);
do_test (15, 15, hlen, klen, 1);
do_test (15, 15, hlen + klen * 4, klen * 4, 0);
do_test (15, 15, hlen + klen * 4, klen * 4, 1);
}
do_test (0, 0, page_size - 1, 16, 0);
do_test (0, 0, page_size - 1, 16, 1);
return ret;
}
#include <support/test-driver.c>