linux/tools/testing/selftests/pidfd/pidfd_xattr_test.c
Christian Brauner 7442d093df
selftests/pidfd: test extended attribute support
Test that extended attributes are permanent.

Link: https://lore.kernel.org/20250618-work-pidfs-persistent-v2-14-98f3456fd552@kernel.org
Reviewed-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-06-23 12:22:08 +02:00

132 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <linux/types.h>
#include <poll.h>
#include <pthread.h>
#include <sched.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syscall.h>
#include <sys/prctl.h>
#include <sys/wait.h>
#include <unistd.h>
#include <sys/socket.h>
#include <linux/kcmp.h>
#include <sys/stat.h>
#include <sys/xattr.h>
#include "pidfd.h"
#include "../kselftest_harness.h"
FIXTURE(pidfs_xattr)
{
pid_t child_pid;
int child_pidfd;
};
FIXTURE_SETUP(pidfs_xattr)
{
self->child_pid = create_child(&self->child_pidfd, CLONE_NEWUSER | CLONE_NEWPID);
EXPECT_GE(self->child_pid, 0);
if (self->child_pid == 0)
_exit(EXIT_SUCCESS);
}
FIXTURE_TEARDOWN(pidfs_xattr)
{
sys_waitid(P_PID, self->child_pid, NULL, WEXITED);
}
TEST_F(pidfs_xattr, set_get_list_xattr_multiple)
{
int ret, i;
char xattr_name[32];
char xattr_value[32];
char buf[32];
const int num_xattrs = 10;
char list[PATH_MAX] = {};
for (i = 0; i < num_xattrs; i++) {
snprintf(xattr_name, sizeof(xattr_name), "trusted.testattr%d", i);
snprintf(xattr_value, sizeof(xattr_value), "testvalue%d", i);
ret = fsetxattr(self->child_pidfd, xattr_name, xattr_value, strlen(xattr_value), 0);
ASSERT_EQ(ret, 0);
}
for (i = 0; i < num_xattrs; i++) {
snprintf(xattr_name, sizeof(xattr_name), "trusted.testattr%d", i);
snprintf(xattr_value, sizeof(xattr_value), "testvalue%d", i);
memset(buf, 0, sizeof(buf));
ret = fgetxattr(self->child_pidfd, xattr_name, buf, sizeof(buf));
ASSERT_EQ(ret, strlen(xattr_value));
ASSERT_EQ(strcmp(buf, xattr_value), 0);
}
ret = flistxattr(self->child_pidfd, list, sizeof(list));
ASSERT_GT(ret, 0);
for (i = 0; i < num_xattrs; i++) {
snprintf(xattr_name, sizeof(xattr_name), "trusted.testattr%d", i);
bool found = false;
for (char *it = list; it < list + ret; it += strlen(it) + 1) {
if (strcmp(it, xattr_name))
continue;
found = true;
break;
}
ASSERT_TRUE(found);
}
for (i = 0; i < num_xattrs; i++) {
snprintf(xattr_name, sizeof(xattr_name), "trusted.testattr%d", i);
ret = fremovexattr(self->child_pidfd, xattr_name);
ASSERT_EQ(ret, 0);
ret = fgetxattr(self->child_pidfd, xattr_name, buf, sizeof(buf));
ASSERT_EQ(ret, -1);
ASSERT_EQ(errno, ENODATA);
}
}
TEST_F(pidfs_xattr, set_get_list_xattr_persistent)
{
int ret;
char buf[32];
char list[PATH_MAX] = {};
ret = fsetxattr(self->child_pidfd, "trusted.persistent", "persistent value", strlen("persistent value"), 0);
ASSERT_EQ(ret, 0);
memset(buf, 0, sizeof(buf));
ret = fgetxattr(self->child_pidfd, "trusted.persistent", buf, sizeof(buf));
ASSERT_EQ(ret, strlen("persistent value"));
ASSERT_EQ(strcmp(buf, "persistent value"), 0);
ret = flistxattr(self->child_pidfd, list, sizeof(list));
ASSERT_GT(ret, 0);
ASSERT_EQ(strcmp(list, "trusted.persistent"), 0)
ASSERT_EQ(close(self->child_pidfd), 0);
self->child_pidfd = -EBADF;
sleep(2);
self->child_pidfd = sys_pidfd_open(self->child_pid, 0);
ASSERT_GE(self->child_pidfd, 0);
memset(buf, 0, sizeof(buf));
ret = fgetxattr(self->child_pidfd, "trusted.persistent", buf, sizeof(buf));
ASSERT_EQ(ret, strlen("persistent value"));
ASSERT_EQ(strcmp(buf, "persistent value"), 0);
ret = flistxattr(self->child_pidfd, list, sizeof(list));
ASSERT_GT(ret, 0);
ASSERT_EQ(strcmp(list, "trusted.persistent"), 0);
}
TEST_HARNESS_MAIN