linux/tools/testing/selftests/filesystems/fclog.c

131 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Author: Aleksa Sarai <cyphar@cyphar.com>
* Copyright (C) 2025 SUSE LLC.
*/
#include <assert.h>
#include <errno.h>
#include <sched.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/mount.h>
#include "../kselftest_harness.h"
#define ASSERT_ERRNO(expected, _t, seen) \
__EXPECT(expected, #expected, \
({__typeof__(seen) _tmp_seen = (seen); \
_tmp_seen >= 0 ? _tmp_seen : -errno; }), #seen, _t, 1)
#define ASSERT_ERRNO_EQ(expected, seen) \
ASSERT_ERRNO(expected, ==, seen)
#define ASSERT_SUCCESS(seen) \
ASSERT_ERRNO(0, <=, seen)
FIXTURE(ns)
{
int host_mntns;
};
FIXTURE_SETUP(ns)
{
/* Stash the old mntns. */
self->host_mntns = open("/proc/self/ns/mnt", O_RDONLY|O_CLOEXEC);
ASSERT_SUCCESS(self->host_mntns);
/* Create a new mount namespace and make it private. */
ASSERT_SUCCESS(unshare(CLONE_NEWNS));
ASSERT_SUCCESS(mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL));
}
FIXTURE_TEARDOWN(ns)
{
ASSERT_SUCCESS(setns(self->host_mntns, CLONE_NEWNS));
ASSERT_SUCCESS(close(self->host_mntns));
}
TEST_F(ns, fscontext_log_enodata)
{
int fsfd = fsopen("tmpfs", FSOPEN_CLOEXEC);
ASSERT_SUCCESS(fsfd);
/* A brand new fscontext has no log entries. */
char buf[128] = {};
for (int i = 0; i < 16; i++)
ASSERT_ERRNO_EQ(-ENODATA, read(fsfd, buf, sizeof(buf)));
ASSERT_SUCCESS(close(fsfd));
}
TEST_F(ns, fscontext_log_errorfc)
{
int fsfd = fsopen("tmpfs", FSOPEN_CLOEXEC);
ASSERT_SUCCESS(fsfd);
ASSERT_ERRNO_EQ(-EINVAL, fsconfig(fsfd, FSCONFIG_SET_STRING, "invalid-arg", "123", 0));
char buf[128] = {};
ASSERT_SUCCESS(read(fsfd, buf, sizeof(buf)));
EXPECT_STREQ("e tmpfs: Unknown parameter 'invalid-arg'\n", buf);
/* The message has been consumed. */
ASSERT_ERRNO_EQ(-ENODATA, read(fsfd, buf, sizeof(buf)));
ASSERT_SUCCESS(close(fsfd));
}
TEST_F(ns, fscontext_log_errorfc_after_fsmount)
{
int fsfd = fsopen("tmpfs", FSOPEN_CLOEXEC);
ASSERT_SUCCESS(fsfd);
ASSERT_ERRNO_EQ(-EINVAL, fsconfig(fsfd, FSCONFIG_SET_STRING, "invalid-arg", "123", 0));
ASSERT_SUCCESS(fsconfig(fsfd, FSCONFIG_CMD_CREATE, NULL, NULL, 0));
int mfd = fsmount(fsfd, FSMOUNT_CLOEXEC, MOUNT_ATTR_NOEXEC | MOUNT_ATTR_NOSUID);
ASSERT_SUCCESS(mfd);
ASSERT_SUCCESS(move_mount(mfd, "", AT_FDCWD, "/tmp", MOVE_MOUNT_F_EMPTY_PATH));
/*
* The fscontext log should still contain data even after
* FSCONFIG_CMD_CREATE and fsmount().
*/
char buf[128] = {};
ASSERT_SUCCESS(read(fsfd, buf, sizeof(buf)));
EXPECT_STREQ("e tmpfs: Unknown parameter 'invalid-arg'\n", buf);
/* The message has been consumed. */
ASSERT_ERRNO_EQ(-ENODATA, read(fsfd, buf, sizeof(buf)));
ASSERT_SUCCESS(close(fsfd));
}
TEST_F(ns, fscontext_log_emsgsize)
{
int fsfd = fsopen("tmpfs", FSOPEN_CLOEXEC);
ASSERT_SUCCESS(fsfd);
ASSERT_ERRNO_EQ(-EINVAL, fsconfig(fsfd, FSCONFIG_SET_STRING, "invalid-arg", "123", 0));
char buf[128] = {};
/*
* Attempting to read a message with too small a buffer should not
* result in the message getting consumed.
*/
ASSERT_ERRNO_EQ(-EMSGSIZE, read(fsfd, buf, 0));
ASSERT_ERRNO_EQ(-EMSGSIZE, read(fsfd, buf, 1));
for (int i = 0; i < 16; i++)
ASSERT_ERRNO_EQ(-EMSGSIZE, read(fsfd, buf, 16));
ASSERT_SUCCESS(read(fsfd, buf, sizeof(buf)));
EXPECT_STREQ("e tmpfs: Unknown parameter 'invalid-arg'\n", buf);
/* The message has been consumed. */
ASSERT_ERRNO_EQ(-ENODATA, read(fsfd, buf, sizeof(buf)));
ASSERT_SUCCESS(close(fsfd));
}
TEST_HARNESS_MAIN