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/*
* Check decoding of mount_setattr syscall.
*
* Copyright (c) 2019-2024 The strace developers.
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include "scno.h"
#include <limits.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
#include <linux/fcntl.h>
#include <linux/mount.h>
static const char *rcstr;
static long
k_mount_setattr(const unsigned int dfd,
const void *fname,
const unsigned int flags,
const void *attr,
kernel_ulong_t size)
{
const kernel_ulong_t fill = (kernel_ulong_t) 0xdefaced00000000ULL;
const kernel_ulong_t bad = (kernel_ulong_t) 0xbadc0dedbadc0dedULL;
const kernel_ulong_t arg1 = fill | dfd;
const kernel_ulong_t arg2 = (uintptr_t) fname;
const kernel_ulong_t arg3 = fill | flags;
const kernel_ulong_t arg4 = (uintptr_t) attr;
const kernel_ulong_t arg5 = size;
const long rc =
syscall(__NR_mount_setattr, arg1, arg2, arg3, arg4, arg5, bad);
rcstr = sprintrc(rc);
return rc;
}
int
main(void)
{
skip_if_unavailable("/proc/self/fd/");
#ifndef PATH_TRACING
char *cwd = get_fd_path(get_dir_fd("."));
#endif
static const char path_full[] = "/dev/full";
const char *const path = tail_memdup(path_full, sizeof(path_full));
char *const fname = tail_alloc(PATH_MAX);
const void *const efault = fname + PATH_MAX;
const char *const empty = efault - 1;
fill_memory_ex(fname, PATH_MAX, '0', 10);
TAIL_ALLOC_OBJECT_CONST_PTR(struct mount_attr, attr);
struct mount_attr *const attr_big = tail_alloc(sizeof(*attr_big) + 8);
static const struct strval32 valid_flags =
{ ARG_STR(AT_SYMLINK_NOFOLLOW|AT_NO_AUTOMOUNT|AT_EMPTY_PATH|AT_RECURSIVE) };
const unsigned int dfd = 9;
k_mount_setattr(-1, 0, AT_SYMLINK_NOFOLLOW, efault, -1U);
#ifndef PATH_TRACING
printf("mount_setattr(-1, NULL, %s, %p, %u) = %s\n",
"AT_SYMLINK_NOFOLLOW", efault, -1U, rcstr);
#endif
k_mount_setattr(-100, fname, 0, attr, MOUNT_ATTR_SIZE_VER0 - 1);
#ifndef PATH_TRACING
printf("mount_setattr(AT_FDCWD<%s>, \"%.*s\"..., 0, %p, %u) = %s\n",
cwd, (int) PATH_MAX - 1, fname,
attr, MOUNT_ATTR_SIZE_VER0 - 1, rcstr);
#endif
fname[PATH_MAX - 1] = '\0';
k_mount_setattr(dfd, fname, -1U,
1 + (void *) attr, MOUNT_ATTR_SIZE_VER0);
printf("mount_setattr(%d<%s>, \"%s\", %s|%#x, %p, %u) = %s\n",
dfd, path, fname, valid_flags.str, ~valid_flags.val,
1 + (void *) attr, MOUNT_ATTR_SIZE_VER0, rcstr);
k_mount_setattr(-1, efault, valid_flags.val,
1 + (void *) attr, MOUNT_ATTR_SIZE_VER0 - 1);
#ifndef PATH_TRACING
printf("mount_setattr(-1, %p, %s, %p, %u) = %s\n",
efault, valid_flags.str,
1 + (void *) attr, MOUNT_ATTR_SIZE_VER0 - 1, rcstr);
#endif
k_mount_setattr(-1, empty, ~valid_flags.val, 0, MOUNT_ATTR_SIZE_VER0);
#ifndef PATH_TRACING
printf("mount_setattr(-1, \"\", %#x /* AT_??? */, NULL, %u) = %s\n",
~valid_flags.val, MOUNT_ATTR_SIZE_VER0, rcstr);
#endif
static const struct strval64 valid_attrs[] = {
{ ARG_STR(MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV|MOUNT_ATTR_NOEXEC|MOUNT_ATTR_NOATIME|MOUNT_ATTR_STRICTATIME|MOUNT_ATTR_NODIRATIME|MOUNT_ATTR_IDMAP|MOUNT_ATTR_NOSYMFOLLOW) },
{ ARG_STR(MOUNT_ATTR_RDONLY|MOUNT_ATTR_NOSUID|MOUNT_ATTR_NODEV|MOUNT_ATTR_NOEXEC|MOUNT_ATTR__ATIME|MOUNT_ATTR_NODIRATIME|MOUNT_ATTR_IDMAP|MOUNT_ATTR_NOSYMFOLLOW) }
};
for (unsigned int j = 0; j < 4; ++j) {
for (unsigned int i = 0; i < ARRAY_SIZE(valid_attrs); ++i) {
struct mount_attr *const a = j > 1 ? attr_big : attr;
const size_t size = j ? sizeof(*a) + 8 : sizeof(*a);
if (j == 3)
memset(attr_big + 1, 0, 8);
else
fill_memory(attr_big + 1, 8);
a->attr_set = 0xffffffff00000000ULL;
a->attr_clr = 0;
a->propagation = MS_UNBINDABLE;
a->userns_fd = dfd;
k_mount_setattr(-1, path, 0, a, size);
printf("mount_setattr(-1, \"%s\", 0"
", {attr_set=0xffffffff00000000 /* MOUNT_ATTR_??? */"
", attr_clr=0, propagation=%s, userns_fd=%u",
path, "MS_UNBINDABLE", dfd);
if (j == 1)
printf(", ???");
if (j == 2) {
printf(", /* bytes %zu..%zu */ \"\\x80\\x81"
"\\x82\\x83\\x84\\x85\\x86\\x87\"",
sizeof(*a), sizeof(*a) + 7);
}
printf("}, %zu) = %s\n", size, rcstr);
a->attr_set = valid_attrs[i].val;
a->attr_clr = ~valid_attrs[i].val;
a->propagation = MS_PRIVATE | MS_SHARED;
a->userns_fd = dfd;
k_mount_setattr(-1, path, 0, a, size);
printf("mount_setattr(-1, \"%s\", 0"
", {attr_set=%s, attr_clr=%#llx /* MOUNT_ATTR_??? */"
", propagation=%#x /* MS_??? */, userns_fd=%d<%s>",
path, valid_attrs[i].str, (unsigned long long) a->attr_clr,
MS_PRIVATE | MS_SHARED, dfd, path);
if (j == 1)
printf(", ???");
if (j == 2) {
printf(", /* bytes %zu..%zu */ \"\\x80\\x81"
"\\x82\\x83\\x84\\x85\\x86\\x87\"",
sizeof(*a), sizeof(*a) + 7);
}
printf("}, %zu) = %s\n", size, rcstr);
a->attr_set = MOUNT_ATTR_NOSUID;
a->attr_clr = MOUNT_ATTR_NODEV;
a->propagation = MS_SLAVE;
a->userns_fd = 0xdefaced00000000ULL | dfd;
k_mount_setattr(dfd, empty, AT_EMPTY_PATH, a, size);
printf("mount_setattr(%d<%s>, \"\", %s, {attr_set=%s, attr_clr=%s"
", propagation=%s, userns_fd=%llu",
dfd, path, "AT_EMPTY_PATH",
"MOUNT_ATTR_NOSUID", "MOUNT_ATTR_NODEV", "MS_SLAVE",
(unsigned long long) a->userns_fd);
if (j == 1)
printf(", ???");
if (j == 2) {
printf(", /* bytes %zu..%zu */ \"\\x80\\x81"
"\\x82\\x83\\x84\\x85\\x86\\x87\"",
sizeof(*a), sizeof(*a) + 7);
}
printf("}, %zu) = %s\n", size, rcstr);
}
}
puts("+++ exited with 0 +++");
return 0;
}
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