mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-14 17:11:06 +00:00
0d50f477f4
This shows up as an assertion failure when sprintf is called with a specifier like "%.8g" and libquadmath is linked in: Fatal glibc error: printf_buffer_as_file.c:31 (__printf_buffer_as_file_commit): assertion failed: file->stream._IO_write_ptr <= file->next->write_end Fix this by detecting pointer wraparound in __vsprintf_internal and saturate the addition to the end of the address space instead. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
127 lines
4.0 KiB
C
127 lines
4.0 KiB
C
/* Tests for fortified sprintf with unknown buffer bounds (bug 30039).
|
|
Copyright (C) 2023 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <printf.h>
|
|
#include <stdarg.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <support/check.h>
|
|
|
|
/* This test is not built with _FORTIFY_SOURCE. Instead it calls the
|
|
appropriate implementation directly. The fortify mode is specified
|
|
in this variable. */
|
|
static int fortify_mode;
|
|
|
|
/* This does not handle long-double redirects etc., but we test only
|
|
format strings that stay within the confines of the base
|
|
implementation. */
|
|
int __vsprintf_chk (char *s, int flag, size_t slen, const char *format,
|
|
va_list ap);
|
|
|
|
/* Invoke vsprintf or __vsprintf_chk according to fortify_mode. */
|
|
static int
|
|
my_vsprintf (char *buf, const char *format, va_list ap)
|
|
{
|
|
int result;
|
|
if (fortify_mode == 0)
|
|
result = vsprintf (buf, format, ap);
|
|
else
|
|
/* Call the fortified version with an unspecified length. */
|
|
result = __vsprintf_chk (buf, fortify_mode - 1, -1, format, ap);
|
|
return result;
|
|
}
|
|
|
|
/* Run one test, with the specified expected output. */
|
|
static void __attribute ((format (printf, 2, 3)))
|
|
do_check (const char *expected, const char *format, ...)
|
|
{
|
|
va_list ap;
|
|
va_start (ap, format);
|
|
|
|
char buf_expected[24];
|
|
memset (buf_expected, '@', sizeof (buf_expected));
|
|
TEST_VERIFY (strlen (expected) < sizeof (buf_expected));
|
|
strcpy (buf_expected, expected);
|
|
|
|
char buf[sizeof (buf_expected)];
|
|
memset (buf, '@', sizeof (buf));
|
|
|
|
int ret = my_vsprintf (buf, format, ap);
|
|
TEST_COMPARE_BLOB (buf_expected, sizeof (buf_expected), buf, sizeof (buf));
|
|
TEST_COMPARE (ret, strlen (expected));
|
|
|
|
va_end (ap);
|
|
}
|
|
|
|
/* Run the tests in all fortify modes. */
|
|
static void
|
|
do_tests (void)
|
|
{
|
|
for (fortify_mode = 0; fortify_mode <= 3; ++fortify_mode)
|
|
{
|
|
do_check ("0", "%d", 0);
|
|
do_check ("-2147483648", "%d", -2147483647 - 1);
|
|
do_check ("-9223372036854775808", "%lld", -9223372036854775807LL - 1);
|
|
do_check ("", "%s", "");
|
|
do_check (" ", "%22s", "");
|
|
do_check ("XXXXXXXXXXXXXXXXXXXXXX", "%s", "XXXXXXXXXXXXXXXXXXXXXX");
|
|
do_check ("1.125000", "%f", 1.125);
|
|
do_check ("1.125", "%g", 1.125);
|
|
do_check ("1.125", "%.8g", 1.125);
|
|
}
|
|
}
|
|
|
|
/* printf callback that falls back to the glibc-supplied
|
|
implementation. */
|
|
static int
|
|
dummy_printf_function (FILE *__stream,
|
|
const struct printf_info *__info,
|
|
const void *const *__args)
|
|
{
|
|
return -2; /* Request fallback. */
|
|
}
|
|
|
|
/* Likewise for the type information. */
|
|
static int
|
|
dummy_arginfo_function (const struct printf_info *info,
|
|
size_t n, int *argtypes, int *size)
|
|
{
|
|
return -1; /* Request fallback. */
|
|
}
|
|
|
|
static int
|
|
do_test (void)
|
|
{
|
|
do_tests ();
|
|
|
|
/* Activate __printf_function_invoke mode. */
|
|
register_printf_specifier ('d', dummy_printf_function,
|
|
dummy_arginfo_function);
|
|
register_printf_specifier ('g', dummy_printf_function,
|
|
dummy_arginfo_function);
|
|
register_printf_specifier ('s', dummy_printf_function,
|
|
dummy_arginfo_function);
|
|
|
|
/* Rerun the tests with callback functions. */
|
|
do_tests ();
|
|
|
|
return 0;
|
|
}
|
|
|
|
#include <support/test-driver.c>
|