mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-27 05:00:15 +00:00
5460617d15
when realpath() input length is close to SSIZE_MAX. 2018-05-09 Paul Pluzhnikov <ppluzhnikov@google.com> [BZ #22786] * stdlib/canonicalize.c (__realpath): Fix overflow in path length computation. * stdlib/Makefile (test-bz22786): New test. * stdlib/test-bz22786.c: New test.
91 lines
2.5 KiB
C
91 lines
2.5 KiB
C
/* Bug 22786: test for buffer overflow in realpath.
|
|
Copyright (C) 2018 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
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
/* This file must be run from within a directory called "stdlib". */
|
|
|
|
#include <errno.h>
|
|
#include <limits.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/types.h>
|
|
#include <support/test-driver.h>
|
|
#include <libc-diag.h>
|
|
|
|
static int
|
|
do_test (void)
|
|
{
|
|
const char dir[] = "bz22786";
|
|
const char lnk[] = "bz22786/symlink";
|
|
|
|
rmdir (dir);
|
|
if (mkdir (dir, 0755) != 0 && errno != EEXIST)
|
|
{
|
|
printf ("mkdir %s: %m\n", dir);
|
|
return EXIT_FAILURE;
|
|
}
|
|
if (symlink (".", lnk) != 0 && errno != EEXIST)
|
|
{
|
|
printf ("symlink (%s, %s): %m\n", dir, lnk);
|
|
return EXIT_FAILURE;
|
|
}
|
|
|
|
const size_t path_len = (size_t) INT_MAX + 1;
|
|
|
|
DIAG_PUSH_NEEDS_COMMENT;
|
|
#if __GNUC_PREREQ (7, 0)
|
|
/* GCC 7 warns about too-large allocations; here we need such
|
|
allocation to succeed for the test to work. */
|
|
DIAG_IGNORE_NEEDS_COMMENT (7, "-Walloc-size-larger-than=");
|
|
#endif
|
|
char *path = malloc (path_len);
|
|
DIAG_POP_NEEDS_COMMENT;
|
|
|
|
if (path == NULL)
|
|
{
|
|
printf ("malloc (%zu): %m\n", path_len);
|
|
return EXIT_UNSUPPORTED;
|
|
}
|
|
|
|
/* Construct very long path = "bz22786/symlink/aaaa....." */
|
|
char *p = mempcpy (path, lnk, sizeof (lnk) - 1);
|
|
*(p++) = '/';
|
|
memset (p, 'a', path_len - (path - p) - 2);
|
|
p[path_len - (path - p) - 1] = '\0';
|
|
|
|
/* This call crashes before the fix for bz22786 on 32-bit platforms. */
|
|
p = realpath (path, NULL);
|
|
|
|
if (p != NULL || errno != ENAMETOOLONG)
|
|
{
|
|
printf ("realpath: %s (%m)", p);
|
|
return EXIT_FAILURE;
|
|
}
|
|
|
|
/* Cleanup. */
|
|
unlink (lnk);
|
|
rmdir (dir);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define TEST_FUNCTION do_test
|
|
#include <support/test-driver.c>
|