161 lines
3.8 KiB
C
161 lines
3.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#define _GNU_SOURCE
|
|
#define __SANE_USERSPACE_TYPES__ // Use ll64
|
|
|
|
#include <inttypes.h>
|
|
#include <unistd.h>
|
|
#include <stdio.h>
|
|
|
|
#include <linux/unistd.h>
|
|
#include <linux/types.h>
|
|
#include <linux/mount.h>
|
|
#include <sys/syscall.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/mman.h>
|
|
#include <sched.h>
|
|
#include <fcntl.h>
|
|
|
|
#include "../../kselftest.h"
|
|
#include "log.h"
|
|
#include "wrappers.h"
|
|
|
|
static long get_file_dev_and_inode(void *addr, struct statx *stx)
|
|
{
|
|
char buf[4096];
|
|
FILE *mapf;
|
|
|
|
mapf = fopen("/proc/self/maps", "r");
|
|
if (mapf == NULL)
|
|
return pr_perror("fopen(/proc/self/maps)");
|
|
|
|
while (fgets(buf, sizeof(buf), mapf)) {
|
|
unsigned long start, end;
|
|
uint32_t maj, min;
|
|
__u64 ino;
|
|
|
|
if (sscanf(buf, "%lx-%lx %*s %*s %x:%x %llu",
|
|
&start, &end, &maj, &min, &ino) != 5)
|
|
return pr_perror("unable to parse: %s", buf);
|
|
if (start == (unsigned long)addr) {
|
|
stx->stx_dev_major = maj;
|
|
stx->stx_dev_minor = min;
|
|
stx->stx_ino = ino;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return pr_err("unable to find the mapping");
|
|
}
|
|
|
|
static int ovl_mount(void)
|
|
{
|
|
int tmpfs, fsfd, ovl;
|
|
|
|
fsfd = sys_fsopen("tmpfs", 0);
|
|
if (fsfd == -1)
|
|
return pr_perror("fsopen(tmpfs)");
|
|
|
|
if (sys_fsconfig(fsfd, FSCONFIG_CMD_CREATE, NULL, NULL, 0) == -1)
|
|
return pr_perror("FSCONFIG_CMD_CREATE");
|
|
|
|
tmpfs = sys_fsmount(fsfd, 0, 0);
|
|
if (tmpfs == -1)
|
|
return pr_perror("fsmount");
|
|
|
|
close(fsfd);
|
|
|
|
/* overlayfs can't be constructed on top of a detached mount. */
|
|
if (sys_move_mount(tmpfs, "", AT_FDCWD, "/tmp", MOVE_MOUNT_F_EMPTY_PATH))
|
|
return pr_perror("move_mount");
|
|
close(tmpfs);
|
|
|
|
if (mkdir("/tmp/w", 0755) == -1 ||
|
|
mkdir("/tmp/u", 0755) == -1 ||
|
|
mkdir("/tmp/l", 0755) == -1)
|
|
return pr_perror("mkdir");
|
|
|
|
fsfd = sys_fsopen("overlay", 0);
|
|
if (fsfd == -1)
|
|
return pr_perror("fsopen(overlay)");
|
|
if (sys_fsconfig(fsfd, FSCONFIG_SET_STRING, "source", "test", 0) == -1 ||
|
|
sys_fsconfig(fsfd, FSCONFIG_SET_STRING, "lowerdir", "/tmp/l", 0) == -1 ||
|
|
sys_fsconfig(fsfd, FSCONFIG_SET_STRING, "upperdir", "/tmp/u", 0) == -1 ||
|
|
sys_fsconfig(fsfd, FSCONFIG_SET_STRING, "workdir", "/tmp/w", 0) == -1)
|
|
return pr_perror("fsconfig");
|
|
if (sys_fsconfig(fsfd, FSCONFIG_CMD_CREATE, NULL, NULL, 0) == -1)
|
|
return pr_perror("fsconfig");
|
|
ovl = sys_fsmount(fsfd, 0, 0);
|
|
if (ovl == -1)
|
|
return pr_perror("fsmount");
|
|
|
|
return ovl;
|
|
}
|
|
|
|
/*
|
|
* Check that the file device and inode shown in /proc/pid/maps match values
|
|
* returned by stat(2).
|
|
*/
|
|
static int test(void)
|
|
{
|
|
struct statx stx, mstx;
|
|
int ovl, fd;
|
|
void *addr;
|
|
|
|
ovl = ovl_mount();
|
|
if (ovl == -1)
|
|
return -1;
|
|
|
|
fd = openat(ovl, "test", O_RDWR | O_CREAT, 0644);
|
|
if (fd == -1)
|
|
return pr_perror("openat");
|
|
|
|
addr = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, fd, 0);
|
|
if (addr == MAP_FAILED)
|
|
return pr_perror("mmap");
|
|
|
|
if (get_file_dev_and_inode(addr, &mstx))
|
|
return -1;
|
|
if (statx(fd, "", AT_EMPTY_PATH | AT_STATX_SYNC_AS_STAT, STATX_INO, &stx))
|
|
return pr_perror("statx");
|
|
|
|
if (stx.stx_dev_major != mstx.stx_dev_major ||
|
|
stx.stx_dev_minor != mstx.stx_dev_minor ||
|
|
stx.stx_ino != mstx.stx_ino)
|
|
return pr_fail("unmatched dev:ino %x:%x:%llx (expected %x:%x:%llx)\n",
|
|
mstx.stx_dev_major, mstx.stx_dev_minor, mstx.stx_ino,
|
|
stx.stx_dev_major, stx.stx_dev_minor, stx.stx_ino);
|
|
|
|
ksft_test_result_pass("devices are matched\n");
|
|
return 0;
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
int fsfd;
|
|
|
|
fsfd = sys_fsopen("overlay", 0);
|
|
if (fsfd == -1) {
|
|
ksft_test_result_skip("unable to create overlay mount\n");
|
|
return 1;
|
|
}
|
|
close(fsfd);
|
|
|
|
/* Create a new mount namespace to not care about cleaning test mounts. */
|
|
if (unshare(CLONE_NEWNS) == -1) {
|
|
ksft_test_result_skip("unable to create a new mount namespace\n");
|
|
return 1;
|
|
}
|
|
if (sys_mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL) == -1) {
|
|
pr_perror("mount");
|
|
return 1;
|
|
}
|
|
|
|
ksft_set_plan(1);
|
|
|
|
if (test())
|
|
return 1;
|
|
|
|
ksft_exit_pass();
|
|
return 0;
|
|
}
|