tests/open_tree_attr.c - master - githubmirror/strace

tests/open_tree_attr.c
178 строк6 KB
Dmitry V. Levin
Update copyright headers
26 апр 2026, 10:00
26 апр 2026, 10:00d4c4467
/*
 * Check decoding of open_tree_attr syscall.
 *
 * Copyright (c) 2019-2026 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 "kernel_fcntl.h"
#include <linux/fcntl.h>
#include <linux/mount.h>

static const char *rcstr;

static long
k_open_tree_attr(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_open_tree_attr, 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(OPEN_TREE_CLONE|OPEN_TREE_NAMESPACE|OPEN_TREE_CLOEXEC|AT_SYMLINK_NOFOLLOW|AT_NO_AUTOMOUNT|AT_EMPTY_PATH|AT_RECURSIVE) };
        const unsigned int dfd = 9;

	k_open_tree_attr(-1, 0, AT_SYMLINK_NOFOLLOW, efault, -1U);
#ifndef PATH_TRACING
	printf("open_tree_attr(-1, NULL, %s, %p, %u) = %s\n",
	       "AT_SYMLINK_NOFOLLOW", efault, -1U, rcstr);
#endif

	k_open_tree_attr(-100, fname, 0, attr, MOUNT_ATTR_SIZE_VER0 - 1);
#ifndef PATH_TRACING
	printf("open_tree_attr(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_open_tree_attr(dfd, fname, -1U,
			1 + (void *) attr, MOUNT_ATTR_SIZE_VER0);
	printf("open_tree_attr(%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_open_tree_attr(-1, efault, valid_flags.val,
			1 + (void *) attr, MOUNT_ATTR_SIZE_VER0 - 1);
#ifndef PATH_TRACING
	printf("open_tree_attr(-1, %p, %s, %p, %u) = %s\n",
	       efault, valid_flags.str,
	       1 + (void *) attr, MOUNT_ATTR_SIZE_VER0 - 1, rcstr);
#endif

	k_open_tree_attr(-1, empty, ~valid_flags.val, 0, MOUNT_ATTR_SIZE_VER0);
#ifndef PATH_TRACING
	printf("open_tree_attr(-1, \"\", %#x /* OPEN_TREE_??? */, 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_open_tree_attr(-1, path, 0, a, size);
			printf("open_tree_attr(-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_open_tree_attr(-1, path, 0, a, size);
			printf("open_tree_attr(-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_open_tree_attr(dfd, empty, AT_EMPTY_PATH, a, size);
			printf("open_tree_attr(%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;
}