src/test/test-mount-util.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2016 Lennart Poettering
   6
   7   systemd is free software; you can redistribute it and/or modify it
   8   under the terms of the GNU Lesser General Public License as published by
   9   the Free Software Foundation; either version 2.1 of the License, or
  10   (at your option) any later version.
  11
  12   systemd is distributed in the hope that it will be useful, but
  13   WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15   Lesser General Public License for more details.
  16
  17   You should have received a copy of the GNU Lesser General Public License
  18   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  19 ***/
  20
  21 #include <sys/mount.h>
  22
  23 #include "alloc-util.h"
  24 #include "def.h"
  25 #include "fd-util.h"
  26 #include "fileio.h"
  27 #include "hashmap.h"
  28 #include "log.h"
  29 #include "log.h"
  30 #include "mount-util.h"
  31 #include "path-util.h"
  32 #include "rm-rf.h"
  33 #include "string-util.h"
  34
  35 static void test_mount_propagation_flags(const char *name, int ret, unsigned long expected) {
  36         long unsigned flags;
  37
  38         assert_se(mount_propagation_flags_from_string(name, &flags) == ret);
  39
  40         if (ret >= 0) {
  41                 const char *c;
  42
  43                 assert_se(flags == expected);
  44
  45                 c = mount_propagation_flags_to_string(flags);
  46                 if (isempty(name))
  47                         assert_se(isempty(c));
  48                 else
  49                         assert_se(streq(c, name));
  50         }
  51 }
  52
  53 static void test_mnt_id(void) {
  54         _cleanup_fclose_ FILE *f = NULL;
  55         Hashmap *h;
  56         Iterator i;
  57         char *p;
  58         void *k;
  59         int r;
  60
  61         assert_se(f = fopen("/proc/self/mountinfo", "re"));
  62         assert_se(h = hashmap_new(&trivial_hash_ops));
  63
  64         for (;;) {
  65                 _cleanup_free_ char *line = NULL, *path = NULL;
  66                 int mnt_id;
  67
  68                 r = read_line(f, LONG_LINE_MAX, &line);
  69                 if (r == 0)
  70                         break;
  71                 assert_se(r > 0);
  72
  73                 assert_se(sscanf(line, "%i %*s %*s %*s %ms", &mnt_id, &path) == 2);
  74
  75                 assert_se(hashmap_put(h, INT_TO_PTR(mnt_id), path) >= 0);
  76                 path = NULL;
  77         }
  78
  79         HASHMAP_FOREACH_KEY(p, k, h, i) {
  80                 int mnt_id = PTR_TO_INT(k), mnt_id2;
  81
  82                 r = path_get_mnt_id(p, &mnt_id2);
  83                 if (r < 0) {
  84                         log_debug_errno(r, "Failed to get the mnt id of %s: %m\n", p);
  85                         continue;
  86                 }
  87
  88                 log_debug("mnt id of %s is %i\n", p, mnt_id2);
  89
  90                 if (mnt_id == mnt_id2)
  91                         continue;
  92
  93                 /* The ids don't match? If so, then there are two mounts on the same path, let's check if that's really
  94                  * the case */
  95                 assert_se(path_equal_ptr(hashmap_get(h, INT_TO_PTR(mnt_id2)), p));
  96         }
  97
  98         hashmap_free_free(h);
  99 }
 100
 101 static void test_path_is_mount_point(void) {
 102         int fd;
 103         char tmp_dir[] = "/tmp/test-path-is-mount-point-XXXXXX";
 104         _cleanup_free_ char *file1 = NULL, *file2 = NULL, *link1 = NULL, *link2 = NULL;
 105         _cleanup_free_ char *dir1 = NULL, *dir1file = NULL, *dirlink1 = NULL, *dirlink1file = NULL;
 106         _cleanup_free_ char *dir2 = NULL, *dir2file = NULL;
 107
 108         assert_se(path_is_mount_point("/", NULL, AT_SYMLINK_FOLLOW) > 0);
 109         assert_se(path_is_mount_point("/", NULL, 0) > 0);
 110         assert_se(path_is_mount_point("//", NULL, AT_SYMLINK_FOLLOW) > 0);
 111         assert_se(path_is_mount_point("//", NULL, 0) > 0);
 112
 113         assert_se(path_is_mount_point("/proc", NULL, AT_SYMLINK_FOLLOW) > 0);
 114         assert_se(path_is_mount_point("/proc", NULL, 0) > 0);
 115         assert_se(path_is_mount_point("/proc/", NULL, AT_SYMLINK_FOLLOW) > 0);
 116         assert_se(path_is_mount_point("/proc/", NULL, 0) > 0);
 117
 118         assert_se(path_is_mount_point("/proc/1", NULL, AT_SYMLINK_FOLLOW) == 0);
 119         assert_se(path_is_mount_point("/proc/1", NULL, 0) == 0);
 120         assert_se(path_is_mount_point("/proc/1/", NULL, AT_SYMLINK_FOLLOW) == 0);
 121         assert_se(path_is_mount_point("/proc/1/", NULL, 0) == 0);
 122
 123         assert_se(path_is_mount_point("/sys", NULL, AT_SYMLINK_FOLLOW) > 0);
 124         assert_se(path_is_mount_point("/sys", NULL, 0) > 0);
 125         assert_se(path_is_mount_point("/sys/", NULL, AT_SYMLINK_FOLLOW) > 0);
 126         assert_se(path_is_mount_point("/sys/", NULL, 0) > 0);
 127
 128         /* we'll create a hierarchy of different kinds of dir/file/link
 129          * layouts:
 130          *
 131          * <tmp>/file1, <tmp>/file2
 132          * <tmp>/link1 -> file1, <tmp>/link2 -> file2
 133          * <tmp>/dir1/
 134          * <tmp>/dir1/file
 135          * <tmp>/dirlink1 -> dir1
 136          * <tmp>/dirlink1file -> dirlink1/file
 137          * <tmp>/dir2/
 138          * <tmp>/dir2/file
 139          */
 140
 141         /* file mountpoints */
 142         assert_se(mkdtemp(tmp_dir) != NULL);
 143         file1 = path_join(NULL, tmp_dir, "file1");
 144         assert_se(file1);
 145         file2 = path_join(NULL, tmp_dir, "file2");
 146         assert_se(file2);
 147         fd = open(file1, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC, 0664);
 148         assert_se(fd > 0);
 149         close(fd);
 150         fd = open(file2, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC, 0664);
 151         assert_se(fd > 0);
 152         close(fd);
 153         link1 = path_join(NULL, tmp_dir, "link1");
 154         assert_se(link1);
 155         assert_se(symlink("file1", link1) == 0);
 156         link2 = path_join(NULL, tmp_dir, "link2");
 157         assert_se(link1);
 158         assert_se(symlink("file2", link2) == 0);
 159
 160         assert_se(path_is_mount_point(file1, NULL, AT_SYMLINK_FOLLOW) == 0);
 161         assert_se(path_is_mount_point(file1, NULL, 0) == 0);
 162         assert_se(path_is_mount_point(link1, NULL, AT_SYMLINK_FOLLOW) == 0);
 163         assert_se(path_is_mount_point(link1, NULL, 0) == 0);
 164
 165         /* directory mountpoints */
 166         dir1 = path_join(NULL, tmp_dir, "dir1");
 167         assert_se(dir1);
 168         assert_se(mkdir(dir1, 0755) == 0);
 169         dirlink1 = path_join(NULL, tmp_dir, "dirlink1");
 170         assert_se(dirlink1);
 171         assert_se(symlink("dir1", dirlink1) == 0);
 172         dirlink1file = path_join(NULL, tmp_dir, "dirlink1file");
 173         assert_se(dirlink1file);
 174         assert_se(symlink("dirlink1/file", dirlink1file) == 0);
 175         dir2 = path_join(NULL, tmp_dir, "dir2");
 176         assert_se(dir2);
 177         assert_se(mkdir(dir2, 0755) == 0);
 178
 179         assert_se(path_is_mount_point(dir1, NULL, AT_SYMLINK_FOLLOW) == 0);
 180         assert_se(path_is_mount_point(dir1, NULL, 0) == 0);
 181         assert_se(path_is_mount_point(dirlink1, NULL, AT_SYMLINK_FOLLOW) == 0);
 182         assert_se(path_is_mount_point(dirlink1, NULL, 0) == 0);
 183
 184         /* file in subdirectory mountpoints */
 185         dir1file = path_join(NULL, dir1, "file");
 186         assert_se(dir1file);
 187         fd = open(dir1file, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC, 0664);
 188         assert_se(fd > 0);
 189         close(fd);
 190
 191         assert_se(path_is_mount_point(dir1file, NULL, AT_SYMLINK_FOLLOW) == 0);
 192         assert_se(path_is_mount_point(dir1file, NULL, 0) == 0);
 193         assert_se(path_is_mount_point(dirlink1file, NULL, AT_SYMLINK_FOLLOW) == 0);
 194         assert_se(path_is_mount_point(dirlink1file, NULL, 0) == 0);
 195
 196         /* these tests will only work as root */
 197         if (mount(file1, file2, NULL, MS_BIND, NULL) >= 0) {
 198                 int rf, rt, rdf, rdt, rlf, rlt, rl1f, rl1t;
 199                 const char *file2d;
 200
 201                 /* files */
 202                 /* capture results in vars, to avoid dangling mounts on failure */
 203                 log_info("%s: %s", __func__, file2);
 204                 rf = path_is_mount_point(file2, NULL, 0);
 205                 rt = path_is_mount_point(file2, NULL, AT_SYMLINK_FOLLOW);
 206
 207                 file2d = strjoina(file2, "/");
 208                 log_info("%s: %s", __func__, file2d);
 209                 rdf = path_is_mount_point(file2d, NULL, 0);
 210                 rdt = path_is_mount_point(file2d, NULL, AT_SYMLINK_FOLLOW);
 211
 212                 log_info("%s: %s", __func__, link2);
 213                 rlf = path_is_mount_point(link2, NULL, 0);
 214                 rlt = path_is_mount_point(link2, NULL, AT_SYMLINK_FOLLOW);
 215
 216                 assert_se(umount(file2) == 0);
 217
 218                 assert_se(rf == 1);
 219                 assert_se(rt == 1);
 220                 assert_se(rdf == -ENOTDIR);
 221                 assert_se(rdt == -ENOTDIR);
 222                 assert_se(rlf == 0);
 223                 assert_se(rlt == 1);
 224
 225                 /* dirs */
 226                 dir2file = path_join(NULL, dir2, "file");
 227                 assert_se(dir2file);
 228                 fd = open(dir2file, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC, 0664);
 229                 assert_se(fd > 0);
 230                 close(fd);
 231
 232                 assert_se(mount(dir2, dir1, NULL, MS_BIND, NULL) >= 0);
 233
 234                 log_info("%s: %s", __func__, dir1);
 235                 rf = path_is_mount_point(dir1, NULL, 0);
 236                 rt = path_is_mount_point(dir1, NULL, AT_SYMLINK_FOLLOW);
 237                 log_info("%s: %s", __func__, dirlink1);
 238                 rlf = path_is_mount_point(dirlink1, NULL, 0);
 239                 rlt = path_is_mount_point(dirlink1, NULL, AT_SYMLINK_FOLLOW);
 240                 log_info("%s: %s", __func__, dirlink1file);
 241                 /* its parent is a mount point, but not /file itself */
 242                 rl1f = path_is_mount_point(dirlink1file, NULL, 0);
 243                 rl1t = path_is_mount_point(dirlink1file, NULL, AT_SYMLINK_FOLLOW);
 244
 245                 assert_se(umount(dir1) == 0);
 246
 247                 assert_se(rf == 1);
 248                 assert_se(rt == 1);
 249                 assert_se(rlf == 0);
 250                 assert_se(rlt == 1);
 251                 assert_se(rl1f == 0);
 252                 assert_se(rl1t == 0);
 253
 254         } else
 255                 printf("Skipping bind mount file test: %m\n");
 256
 257         assert_se(rm_rf(tmp_dir, REMOVE_ROOT|REMOVE_PHYSICAL) == 0);
 258 }
 259
 260 static void test_mount_option_mangle(void) {
 261         char *opts = NULL;
 262         unsigned long f;
 263
 264         assert_se(mount_option_mangle(NULL, MS_RDONLY|MS_NOSUID, &f, &opts) == 0);
 265         assert_se(f == (MS_RDONLY|MS_NOSUID));
 266         assert_se(opts == NULL);
 267
 268         assert_se(mount_option_mangle("", MS_RDONLY|MS_NOSUID, &f, &opts) == 0);
 269         assert_se(f == (MS_RDONLY|MS_NOSUID));
 270         assert_se(opts == NULL);
 271
 272         assert_se(mount_option_mangle("ro,nosuid,nodev,noexec", 0, &f, &opts) == 0);
 273         assert_se(f == (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC));
 274         assert_se(opts == NULL);
 275
 276         assert_se(mount_option_mangle("ro,nosuid,nodev,noexec,mode=755", 0, &f, &opts) == 0);
 277         assert_se(f == (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC));
 278         assert_se(streq(opts, "mode=755"));
 279         opts = mfree(opts);
 280
 281         assert_se(mount_option_mangle("rw,nosuid,foo,hogehoge,nodev,mode=755", 0, &f, &opts) == 0);
 282         assert_se(f == (MS_NOSUID|MS_NODEV));
 283         assert_se(streq(opts, "foo,hogehoge,mode=755"));
 284         opts = mfree(opts);
 285
 286         assert_se(mount_option_mangle("rw,nosuid,nodev,noexec,relatime,net_cls,net_prio", MS_RDONLY, &f, &opts) == 0);
 287         assert_se(f == (MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_RELATIME));
 288         assert_se(streq(opts, "net_cls,net_prio"));
 289         opts = mfree(opts);
 290
 291         assert_se(mount_option_mangle("rw,nosuid,nodev,relatime,size=1630748k,mode=700,uid=1000,gid=1000", MS_RDONLY, &f, &opts) == 0);
 292         assert_se(f == (MS_NOSUID|MS_NODEV|MS_RELATIME));
 293         assert_se(streq(opts, "size=1630748k,mode=700,uid=1000,gid=1000"));
 294         opts = mfree(opts);
 295
 296         assert_se(mount_option_mangle("size=1630748k,rw,gid=1000,,,nodev,relatime,,mode=700,nosuid,uid=1000", MS_RDONLY, &f, &opts) == 0);
 297         assert_se(f == (MS_NOSUID|MS_NODEV|MS_RELATIME));
 298         assert_se(streq(opts, "size=1630748k,gid=1000,mode=700,uid=1000"));
 299         opts = mfree(opts);
 300
 301         assert_se(mount_option_mangle("rw,exec,size=8143984k,nr_inodes=2035996,mode=755", MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, &f, &opts) == 0);
 302         assert_se(f == (MS_NOSUID|MS_NODEV));
 303         assert_se(streq(opts, "size=8143984k,nr_inodes=2035996,mode=755"));
 304         opts = mfree(opts);
 305
 306         assert_se(mount_option_mangle("rw,relatime,fmask=0022,,,dmask=0022", MS_RDONLY, &f, &opts) == 0);
 307         assert_se(f == MS_RELATIME);
 308         assert_se(streq(opts, "fmask=0022,dmask=0022"));
 309         opts = mfree(opts);
 310
 311         assert_se(mount_option_mangle("rw,relatime,fmask=0022,dmask=0022,\"hogehoge", MS_RDONLY, &f, &opts) < 0);
 312 }
 313
 314 int main(int argc, char *argv[]) {
 315
 316         log_set_max_level(LOG_DEBUG);
 317
 318         test_mount_propagation_flags("shared", 0, MS_SHARED);
 319         test_mount_propagation_flags("slave", 0, MS_SLAVE);
 320         test_mount_propagation_flags("private", 0, MS_PRIVATE);
 321         test_mount_propagation_flags(NULL, 0, 0);
 322         test_mount_propagation_flags("", 0, 0);
 323         test_mount_propagation_flags("xxxx", -EINVAL, 0);
 324         test_mount_propagation_flags(" ", -EINVAL, 0);
 325
 326         test_mnt_id();
 327         test_path_is_mount_point();
 328         test_mount_option_mangle();
 329
 330         return 0;
 331 }