testcases/kernel/syscalls/execve/execve02.c

/*
 *
 *   Copyright (c) International Business Machines  Corp., 2001
 *
 *   This program is free software;  you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program 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 General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program;  if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
 * NAME
 *	execve02.c
 *
 * DESCRIPTION
 *	Testcase to check whether execve(2) sets errno to EACCES correctly
 *
 * ALGORITHM
 *	1.	Attempt to execve(2) an executable owned by root with
 *		no execute permissions for the other users, fails when
 *		execve(2) is used as a non-root user (ltpuser1). The errno
 *		should be EACCES.
 *
 * USAGE:  <for command-line>
 *  execve02 -F <test file> [-c n] [-e] [-i n] [-I x] [-P x] [-t]
 *     where,  -c n : Run n copies concurrently.
 *             -e   : Turn on errno logging.
 *             -i n : Execute test n times.
 *             -I x : Execute test for x seconds.
 *             -P x : Pause for x seconds between iterations.
 *             -t   : Turn on syscall timing.
 *
 * HISTORY
 *	07/2001 Ported by Wayne Boyer
 *
 *      21/04/2008 Renaud Lottiaux (Renaud.Lottiaux@kerlabs.com)
 *      - Fix concurrency issue. In case of concurrent executions, all tasks
 *        was using the same file, changing its mode and leading to invalid
 *        mode for some of them.
 *
 * RESTRICTIONS
 *	Must run test with the -F <test file> option.
 */

#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <errno.h>
#include <libgen.h>
#include <pwd.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "test.h"

char *TCID = "execve02";
int TST_TOTAL = 1;

void setup(char *);
void cleanup(void);
void help(void);

int Fflag = 0;
char *test_app;

/* for test specific parse_opts options - in this case "-F" */
option_t options[] = {
	{"F:", &Fflag, &test_app},
	{NULL, NULL, NULL}
};

char user1name[] = "nobody";
extern struct passwd *my_getpwnam(char *);
struct passwd *ltpuser1;

int main(int ac, char **av)
{
	int lc;
	const char *msg;
	int status, retval = 0;
	pid_t pid;

	if ((msg = parse_opts(ac, av, options, &help)) != NULL)
		tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);

	if (!Fflag)
		tst_brkm(TBROK, NULL, "You must specify a test executable with "
			 "the -F option.");

	setup(av[0]);

	for (lc = 0; TEST_LOOPING(lc); lc++) {

		tst_count = 0;

		if (chmod(test_app, 0700) != 0)
			tst_resm(TFAIL | TERRNO, "chmod failed");

		if ((pid = FORK_OR_VFORK()) == -1)
			tst_brkm(TBROK | TERRNO, cleanup, "fork failed");

		if (pid == 0) {
			if (seteuid(ltpuser1->pw_uid) == -1)
				perror("setuid failed");
			char *argv[2];

			argv[0] = basename(test_app);
			argv[1] = 0;

			if (argv[0] == NULL)
				perror("basename failed");
			TEST(execve(test_app, argv, NULL));

			if (TEST_ERRNO != EACCES) {
				retval = 1;
				perror("execve failed unexpectedly");
			} else
				printf
				    ("execve failed with EACCES as expected\n");

			if (seteuid(0) == -1)
				perror("setuid(0) failed");

			if (chmod(test_app, 0755) == -1)
				perror("chmod #2 failed");
			exit(retval);
		}
		if (wait(&status) == -1)
			tst_brkm(TBROK | TERRNO, cleanup, "wait failed");
		if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
			tst_resm(TFAIL, "child exited abnormally");

	}
	cleanup();

	tst_exit();
}

/*
 * help() - Prints out the help message for the -F option defined
 *          by this test.
 */
void help(void)
{
	printf("  -F <test file> : for example, 'execve02 -F test3'\n");
}

void setup(char *argv0)
{
	char *cmd, *pwd = NULL;
	char test_path[MAXPATHLEN];

	tst_require_root(NULL);

	if (test_app[0] == '/')
		strncpy(test_path, test_app, sizeof(test_path));
	else {
		if ((pwd = get_current_dir_name()) == NULL)
			tst_brkm(TBROK | TERRNO, NULL, "getcwd failed");

		snprintf(test_path, sizeof(test_path), "%s/%s",
			 pwd, basename(test_app));

		free(pwd);
	}

	cmd = malloc(strlen(test_path) + strlen("cp -p \"") + strlen("\" .") + 1);
	if (cmd == NULL)
		tst_brkm(TBROK | TERRNO, NULL, "Cannot alloc command string");

	tst_sig(FORK, DEF_HANDLER, cleanup);

	tst_tmpdir();

	sprintf(cmd, "cp -p \"%s\" .", test_path);
	if (system(cmd) != 0)
		tst_brkm(TBROK, NULL, "command failed: %s", cmd);
	free(cmd);

	umask(0);

	ltpuser1 = my_getpwnam(user1name);
}

void cleanup(void)
{
	tst_rmdir();
}