glibc/posix/tst-vfork3.c
Florian Weimer c22553effb support: Prevent multiple deletion of temporary files
Otherwise, another user might recreate these files after the first
deletion.  Particularly with temporary directories, this could result
in the removal of unintended files through symbol link attacks.
2017-05-08 16:20:40 +02:00

176 lines
4.6 KiB
C

/* Test for vfork functions.
Copyright (C) 2007-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.com>, 2007.
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/>. */
#include <errno.h>
#include <fcntl.h>
#include <mcheck.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>
static int do_test (void);
static void do_prepare (void);
char *tmpdirname;
#define TEST_FUNCTION do_test ()
#define PREPARE(argc, argv) do_prepare ()
#include "../test-skeleton.c"
static void
run_script (const char *script, char *const argv[])
{
for (size_t i = 0; i < 5; i++)
{
pid_t pid = vfork ();
if (pid < 0)
FAIL_EXIT1 ("vfork failed: %m");
else if (pid == 0)
{
execvp (script, argv);
_exit (errno);
}
int status;
if (TEMP_FAILURE_RETRY (waitpid (pid, &status, 0)) != pid)
FAIL_EXIT1 ("waitpid failed");
else if (status != 0)
{
if (WIFEXITED (status))
FAIL_EXIT1 ("%s failed with status %d\n", script,
WEXITSTATUS (status));
else
FAIL_EXIT1 ("%s killed by signal %d\n", script,
WTERMSIG (status));
}
}
}
static int
do_test (void)
{
mtrace ();
const char *path = getenv ("PATH");
if (path == NULL)
path = "/bin";
char pathbuf[strlen (tmpdirname) + 1 + strlen (path) + 1];
strcpy (stpcpy (stpcpy (pathbuf, tmpdirname), ":"), path);
if (setenv ("PATH", pathbuf, 1) < 0)
{
puts ("setenv failed");
return 1;
}
/* Although manual states first argument should be the script name itself,
current execv{p,e} implementation allows it. */
char *argv00[] = { NULL };
run_script ("script0.sh", argv00);
char *argv01[] = { (char*) "script0.sh", NULL };
run_script ("script0.sh", argv01);
char *argv1[] = { (char *) "script1.sh", (char *) "1", NULL };
run_script ("script1.sh", argv1);
char *argv2[] = { (char *) "script2.sh", (char *) "2", NULL };
run_script ("script2.sh", argv2);
/* Same as before but with execlp. */
for (size_t i = 0; i < 5; i++)
{
pid_t pid = vfork ();
if (pid < 0)
{
printf ("vfork failed: %m\n");
return 1;
}
else if (pid == 0)
{
execlp ("script2.sh", "script2.sh", "3", NULL);
_exit (errno);
}
int status;
if (TEMP_FAILURE_RETRY (waitpid (pid, &status, 0)) != pid)
{
puts ("waitpid failed");
return 1;
}
else if (status != 0)
{
printf ("script2.sh failed with status %d\n", status);
return 1;
}
}
unsetenv ("PATH");
char *argv4[] = { (char *) "echo", (char *) "script 4", NULL };
run_script ("echo", argv4);
return 0;
}
static void
create_script (const char *script, const char *contents, size_t size)
{
int fd = open (script, O_WRONLY | O_CREAT, 0700);
if (fd < 0
|| TEMP_FAILURE_RETRY (write (fd, contents, size)) != size
|| fchmod (fd, S_IRUSR | S_IXUSR) < 0)
FAIL_EXIT1 ("could not write %s\n", script);
close (fd);
}
static void
do_prepare (void)
{
size_t len = strlen (test_dir) + sizeof ("/tst-vfork3.XXXXXX");
tmpdirname = malloc (len);
if (tmpdirname == NULL)
FAIL_EXIT1 ("out of memory");
strcpy (stpcpy (tmpdirname, test_dir), "/tst-vfork3.XXXXXX");
tmpdirname = mkdtemp (tmpdirname);
if (tmpdirname == NULL)
FAIL_EXIT1 ("could not create temporary directory");
char script0[len + sizeof "/script0.sh"];
char script1[len + sizeof "/script1.sh"];
char script2[len + sizeof "/script2.sh"];
strcpy (stpcpy (script0, tmpdirname), "/script0.sh");
strcpy (stpcpy (script1, tmpdirname), "/script1.sh");
strcpy (stpcpy (script2, tmpdirname), "/script2.sh");
add_temp_file (tmpdirname);
add_temp_file (script0);
add_temp_file (script1);
add_temp_file (script2);
const char content0[] = "#!/bin/sh\necho empty\n";
create_script (script0, content0, sizeof content0);
const char content1[] = "#!/bin/sh\necho script $1\n";
create_script (script1, content1, sizeof content1);
const char content2[] = "echo script $1\n";
create_script (script2, content2, sizeof content2);
}