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/*
* Check decoding of fsmount syscall.
*
* Copyright (c) 2019-2021 Dmitry V. Levin <ldv@strace.io>
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include "scno.h"
#include <fcntl.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
static const char *errstr;
static long
k_fsmount(const unsigned int fs_fd,
const unsigned int flags,
const unsigned int attr_flags)
{
const kernel_ulong_t fill = (kernel_ulong_t) 0xdefaced00000000ULL;
const kernel_ulong_t bad = (kernel_ulong_t) 0xbadc0dedbadc0dedULL;
const kernel_ulong_t arg1 = fill | fs_fd;
const kernel_ulong_t arg2 = fill | flags;
const kernel_ulong_t arg3 = fill | attr_flags;
const long rc = syscall(__NR_fsmount,
arg1, arg2, arg3, bad, bad, bad);
errstr = sprintrc(rc);
return rc;
}
int
main(void)
{
skip_if_unavailable("/proc/self/fd/");
static const char path[] = "/dev/full";
int fd = open(path, O_WRONLY);
if (fd < 0)
perror_msg_and_fail("open: %s", path);
struct {
unsigned int val;
const char *str;
} flags[] = {
{ ARG_STR(0) },
{ 1, "FSMOUNT_CLOEXEC" },
{ 2, "0x2 /* FSMOUNT_??? */" },
{ 0xfffffffe, "0xfffffffe /* FSMOUNT_??? */" },
{ -1, "FSMOUNT_CLOEXEC|0xfffffffe" }
},
attrs[] = {
{ ARG_STR(0) },
{ 1, "MOUNT_ATTR_RDONLY" },
{ 0x10, "MOUNT_ATTR_NOATIME" },
{ 0xbf, "MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV"
"|MOUNT_ATTR_NOEXEC|MOUNT_ATTR_NOATIME"
"|MOUNT_ATTR_STRICTATIME|MOUNT_ATTR_NODIRATIME" },
{ 0x40, "0x40 /* MOUNT_ATTR_??? */" },
{ 0xffffff40, "0xffffff40 /* MOUNT_ATTR_??? */" },
{ -1, "MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV"
"|MOUNT_ATTR_NOEXEC|MOUNT_ATTR_NOATIME"
"|MOUNT_ATTR_STRICTATIME|MOUNT_ATTR_NODIRATIME"
"|0xffffff40" }
};
for (unsigned int i = 0; i < ARRAY_SIZE(flags); ++i) {
for (unsigned int j = 0; j < ARRAY_SIZE(attrs); ++j) {
k_fsmount(-1, flags[i].val, attrs[j].val);
printf("fsmount(-1, %s, %s) = %s\n",
flags[i].str, attrs[j].str, errstr);
k_fsmount(-100, flags[i].val, attrs[j].val);
printf("fsmount(-100, %s, %s) = %s\n",
flags[i].str, attrs[j].str, errstr);
k_fsmount(fd, flags[i].val, attrs[j].val);
printf("fsmount(%d<%s>, %s, %s) = %s\n",
fd, path, flags[i].str, attrs[j].str, errstr);
}
}
puts("+++ exited with 0 +++");
return 0;
}
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