Bug Summary

File:build-scan/../src/core/namespace.c
Warning:line 1456, column 25
Potential leak of memory pointed to by 's'

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-unknown-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name namespace.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -mframe-pointer=all -relaxed-aliasing -menable-no-infs -menable-no-nans -menable-unsafe-fp-math -fno-signed-zeros -mreassociate -freciprocal-math -fdenormal-fp-math=preserve-sign,preserve-sign -ffp-contract=fast -fno-rounding-math -ffast-math -ffinite-math-only -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -resource-dir /usr/lib64/clang/12.0.0 -include config.h -I src/core/libcore.a.p -I src/core -I ../src/core -I src/basic -I ../src/basic -I src/shared -I ../src/shared -I src/systemd -I ../src/systemd -I src/journal -I ../src/journal -I src/journal-remote -I ../src/journal-remote -I src/nspawn -I ../src/nspawn -I src/resolve -I ../src/resolve -I src/timesync -I ../src/timesync -I ../src/time-wait-sync -I src/login -I ../src/login -I src/udev -I ../src/udev -I src/libudev -I ../src/libudev -I ../src/libsystemd/sd-bus -I ../src/libsystemd/sd-device -I ../src/libsystemd/sd-hwdb -I ../src/libsystemd/sd-id128 -I ../src/libsystemd/sd-netlink -I ../src/libsystemd/sd-network -I src/libsystemd-network -I ../src/libsystemd-network -I . -I .. -I /usr/include/libmount -I /usr/include/blkid -D _FILE_OFFSET_BITS=64 -internal-isystem /usr/local/include -internal-isystem /usr/lib64/clang/12.0.0/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -Wwrite-strings -Wno-unused-parameter -Wno-missing-field-initializers -Wno-unused-result -Wno-format-signedness -Wno-error=nonnull -std=gnu99 -fconst-strings -fdebug-compilation-dir /home/mrc0mmand/repos/@redhat-plumbers/systemd-rhel8/build-scan -ferror-limit 19 -fvisibility hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -analyzer-output=html -faddrsig -o /tmp/scan-build-2021-07-16-221226-1465241-1 -x c ../src/core/namespace.c
1/* SPDX-License-Identifier: LGPL-2.1+ */
2
3#include <errno(*__errno_location ()).h>
4#include <sched.h>
5#include <stdio.h>
6#include <string.h>
7#include <sys/mount.h>
8#include <sys/stat.h>
9#include <unistd.h>
10#include <linux1/fs.h>
11
12#include "alloc-util.h"
13#include "base-filesystem.h"
14#include "dev-setup.h"
15#include "fd-util.h"
16#include "fs-util.h"
17#include "label.h"
18#include "loop-util.h"
19#include "loopback-setup.h"
20#include "missing.h"
21#include "mkdir.h"
22#include "mount-util.h"
23#include "namespace.h"
24#include "path-util.h"
25#include "selinux-util.h"
26#include "socket-util.h"
27#include "stat-util.h"
28#include "string-table.h"
29#include "string-util.h"
30#include "strv.h"
31#include "umask-util.h"
32#include "user-util.h"
33#include "util.h"
34
35#define DEV_MOUNT_OPTIONS(2|(1<<24)|8) (MS_NOSUID2|MS_STRICTATIME(1<<24)|MS_NOEXEC8)
36
37typedef enum MountMode {
38 /* This is ordered by priority! */
39 INACCESSIBLE,
40 BIND_MOUNT,
41 BIND_MOUNT_RECURSIVE,
42 PRIVATE_TMP,
43 PRIVATE_DEV,
44 BIND_DEV,
45 EMPTY_DIR,
46 SYSFS,
47 PROCFS,
48 READONLY,
49 READWRITE,
50 TMPFS,
51} MountMode;
52
53typedef struct MountEntry {
54 const char *path_const; /* Memory allocated on stack or static */
55 MountMode mode:5;
56 bool_Bool ignore:1; /* Ignore if path does not exist? */
57 bool_Bool has_prefix:1; /* Already is prefixed by the root dir? */
58 bool_Bool read_only:1; /* Shall this mount point be read-only? */
59 bool_Bool applied:1; /* Already applied */
60 char *path_malloc; /* Use this instead of 'path_const' if we had to allocate memory */
61 const char *source_const; /* The source path, for bind mounts */
62 char *source_malloc;
63 const char *options_const;/* Mount options for tmpfs */
64 char *options_malloc;
65 unsigned long flags; /* Mount flags used by EMPTY_DIR and TMPFS. Do not include MS_RDONLY here, but please use read_only. */
66 unsigned n_followed;
67} MountEntry;
68
69/* If MountAPIVFS= is used, let's mount /sys and /proc into the it, but only as a fallback if the user hasn't mounted
70 * something there already. These mounts are hence overridden by any other explicitly configured mounts. */
71static const MountEntry apivfs_table[] = {
72 { "/proc", PROCFS, false0 },
73 { "/dev", BIND_DEV, false0 },
74 { "/sys", SYSFS, false0 },
75};
76
77/* ProtectKernelTunables= option and the related filesystem APIs */
78static const MountEntry protect_kernel_tunables_table[] = {
79 { "/proc/acpi", READONLY, true1 },
80 { "/proc/apm", READONLY, true1 }, /* Obsolete API, there's no point in permitting access to this, ever */
81 { "/proc/asound", READONLY, true1 },
82 { "/proc/bus", READONLY, true1 },
83 { "/proc/fs", READONLY, true1 },
84 { "/proc/irq", READONLY, true1 },
85 { "/proc/kallsyms", INACCESSIBLE, true1 },
86 { "/proc/kcore", INACCESSIBLE, true1 },
87 { "/proc/latency_stats", READONLY, true1 },
88 { "/proc/mtrr", READONLY, true1 },
89 { "/proc/scsi", READONLY, true1 },
90 { "/proc/sys", READONLY, false0 },
91 { "/proc/sysrq-trigger", READONLY, true1 },
92 { "/proc/timer_stats", READONLY, true1 },
93 { "/sys", READONLY, false0 },
94 { "/sys/fs/bpf", READONLY, true1 },
95 { "/sys/fs/cgroup", READWRITE, false0 }, /* READONLY is set by ProtectControlGroups= option */
96 { "/sys/fs/selinux", READWRITE, true1 },
97 { "/sys/kernel/debug", READONLY, true1 },
98 { "/sys/kernel/tracing", READONLY, true1 },
99};
100
101/* ProtectKernelModules= option */
102static const MountEntry protect_kernel_modules_table[] = {
103#if HAVE_SPLIT_USR0
104 { "/lib/modules", INACCESSIBLE, true1 },
105#endif
106 { "/usr/lib/modules", INACCESSIBLE, true1 },
107};
108
109/*
110 * ProtectHome=read-only table, protect $HOME and $XDG_RUNTIME_DIR and rest of
111 * system should be protected by ProtectSystem=
112 */
113static const MountEntry protect_home_read_only_table[] = {
114 { "/home", READONLY, true1 },
115 { "/run/user", READONLY, true1 },
116 { "/root", READONLY, true1 },
117};
118
119/* ProtectHome=tmpfs table */
120static const MountEntry protect_home_tmpfs_table[] = {
121 { "/home", TMPFS, true1, .read_only = true1, .options_const = "mode=0755", .flags = MS_NODEV4|MS_STRICTATIME(1<<24) },
122 { "/run/user", TMPFS, true1, .read_only = true1, .options_const = "mode=0755", .flags = MS_NODEV4|MS_STRICTATIME(1<<24) },
123 { "/root", TMPFS, true1, .read_only = true1, .options_const = "mode=0700", .flags = MS_NODEV4|MS_STRICTATIME(1<<24) },
124};
125
126/* ProtectHome=yes table */
127static const MountEntry protect_home_yes_table[] = {
128 { "/home", INACCESSIBLE, true1 },
129 { "/run/user", INACCESSIBLE, true1 },
130 { "/root", INACCESSIBLE, true1 },
131};
132
133/* ProtectSystem=yes table */
134static const MountEntry protect_system_yes_table[] = {
135 { "/usr", READONLY, false0 },
136 { "/boot", READONLY, true1 },
137 { "/efi", READONLY, true1 },
138#if HAVE_SPLIT_USR0
139 { "/lib", READONLY, true1 },
140 { "/lib64", READONLY, true1 },
141 { "/bin", READONLY, true1 },
142# if HAVE_SPLIT_BIN1
143 { "/sbin", READONLY, true1 },
144# endif
145#endif
146};
147
148/* ProtectSystem=full includes ProtectSystem=yes */
149static const MountEntry protect_system_full_table[] = {
150 { "/usr", READONLY, false0 },
151 { "/boot", READONLY, true1 },
152 { "/efi", READONLY, true1 },
153 { "/etc", READONLY, false0 },
154#if HAVE_SPLIT_USR0
155 { "/lib", READONLY, true1 },
156 { "/lib64", READONLY, true1 },
157 { "/bin", READONLY, true1 },
158# if HAVE_SPLIT_BIN1
159 { "/sbin", READONLY, true1 },
160# endif
161#endif
162};
163
164/*
165 * ProtectSystem=strict table. In this strict mode, we mount everything
166 * read-only, except for /proc, /dev, /sys which are the kernel API VFS,
167 * which are left writable, but PrivateDevices= + ProtectKernelTunables=
168 * protect those, and these options should be fully orthogonal.
169 * (And of course /home and friends are also left writable, as ProtectHome=
170 * shall manage those, orthogonally).
171 */
172static const MountEntry protect_system_strict_table[] = {
173 { "/", READONLY, false0 },
174 { "/proc", READWRITE, false0 }, /* ProtectKernelTunables= */
175 { "/sys", READWRITE, false0 }, /* ProtectKernelTunables= */
176 { "/dev", READWRITE, false0 }, /* PrivateDevices= */
177 { "/home", READWRITE, true1 }, /* ProtectHome= */
178 { "/run/user", READWRITE, true1 }, /* ProtectHome= */
179 { "/root", READWRITE, true1 }, /* ProtectHome= */
180};
181
182static const char *mount_entry_path(const MountEntry *p) {
183 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 183, __PRETTY_FUNCTION__
); } while (0);
184
185 /* Returns the path of this bind mount. If the malloc()-allocated ->path_buffer field is set we return that,
186 * otherwise the stack/static ->path field is returned. */
187
188 return p->path_malloc ?: p->path_const;
189}
190
191static bool_Bool mount_entry_read_only(const MountEntry *p) {
192 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 192, __PRETTY_FUNCTION__
); } while (0);
193
194 return p->read_only || IN_SET(p->mode, READONLY, INACCESSIBLE)({ _Bool _found = 0; static __attribute__ ((unused)) char _static_assert__macros_need_to_be_extended
[20 - sizeof((int[]){READONLY, INACCESSIBLE})/sizeof(int)]; switch
(p->mode) { case READONLY: case INACCESSIBLE: _found = 1; break
; default: break; } _found; });
195}
196
197static const char *mount_entry_source(const MountEntry *p) {
198 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 198, __PRETTY_FUNCTION__
); } while (0);
199
200 return p->source_malloc ?: p->source_const;
201}
202
203static const char *mount_entry_options(const MountEntry *p) {
204 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 204, __PRETTY_FUNCTION__
); } while (0);
205
206 return p->options_malloc ?: p->options_const;
207}
208
209static void mount_entry_done(MountEntry *p) {
210 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 210, __PRETTY_FUNCTION__
); } while (0);
211
212 p->path_malloc = mfree(p->path_malloc);
213 p->source_malloc = mfree(p->source_malloc);
214 p->options_malloc = mfree(p->options_malloc);
215}
216
217static int append_access_mounts(MountEntry **p, char **strv, MountMode mode, bool_Bool forcibly_require_prefix) {
218 char **i;
219
220 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 220, __PRETTY_FUNCTION__
); } while (0);
221
222 /* Adds a list of user-supplied READWRITE/READONLY/INACCESSIBLE entries */
223
224 STRV_FOREACH(i, strv)for ((i) = (strv); (i) && *(i); (i)++) {
225 bool_Bool ignore = false0, needs_prefix = false0;
226 const char *e = *i;
227
228 /* Look for any prefixes */
229 if (startswith(e, "-")) {
230 e++;
231 ignore = true1;
232 }
233 if (startswith(e, "+")) {
234 e++;
235 needs_prefix = true1;
236 }
237
238 if (!path_is_absolute(e))
239 return -EINVAL22;
240
241 *((*p)++) = (MountEntry) {
242 .path_const = e,
243 .mode = mode,
244 .ignore = ignore,
245 .has_prefix = !needs_prefix && !forcibly_require_prefix,
246 };
247 }
248
249 return 0;
250}
251
252static int append_empty_dir_mounts(MountEntry **p, char **strv) {
253 char **i;
254
255 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 255, __PRETTY_FUNCTION__
); } while (0);
256
257 /* Adds tmpfs mounts to provide readable but empty directories. This is primarily used to implement the
258 * "/private/" boundary directories for DynamicUser=1. */
259
260 STRV_FOREACH(i, strv)for ((i) = (strv); (i) && *(i); (i)++) {
261
262 *((*p)++) = (MountEntry) {
263 .path_const = *i,
264 .mode = EMPTY_DIR,
265 .ignore = false0,
266 .has_prefix = false0,
267 .read_only = true1,
268 .options_const = "mode=755",
269 .flags = MS_NOSUID2|MS_NOEXEC8|MS_NODEV4|MS_STRICTATIME(1<<24),
270 };
271 }
272
273 return 0;
274}
275
276static int append_bind_mounts(MountEntry **p, const BindMount *binds, size_t n) {
277 size_t i;
278
279 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 279, __PRETTY_FUNCTION__
); } while (0);
280
281 for (i = 0; i < n; i++) {
282 const BindMount *b = binds + i;
283
284 *((*p)++) = (MountEntry) {
285 .path_const = b->destination,
286 .mode = b->recursive ? BIND_MOUNT_RECURSIVE : BIND_MOUNT,
287 .read_only = b->read_only,
288 .source_const = b->source,
289 .ignore = b->ignore_enoent,
290 };
291 }
292
293 return 0;
294}
295
296static int append_tmpfs_mounts(MountEntry **p, const TemporaryFileSystem *tmpfs, size_t n) {
297 size_t i;
298 int r;
299
300 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 300, __PRETTY_FUNCTION__
); } while (0);
301
302 for (i = 0; i < n; i++) {
303 const TemporaryFileSystem *t = tmpfs + i;
304 _cleanup_free___attribute__((cleanup(freep))) char *o = NULL((void*)0), *str = NULL((void*)0);
305 unsigned long flags = MS_NODEV4|MS_STRICTATIME(1<<24);
306 bool_Bool ro = false0;
307
308 if (!path_is_absolute(t->path))
309 return -EINVAL22;
310
311 if (!isempty(t->options)) {
312 str = strjoin("mode=0755,", t->options)strjoin_real(("mode=0755,"), t->options, ((void*)0));
313 if (!str)
314 return -ENOMEM12;
315
316 r = mount_option_mangle(str, MS_NODEV4|MS_STRICTATIME(1<<24), &flags, &o);
317 if (r < 0)
318 return r;
319
320 ro = flags & MS_RDONLY1;
321 if (ro)
322 flags ^= MS_RDONLY1;
323 }
324
325 *((*p)++) = (MountEntry) {
326 .path_const = t->path,
327 .mode = TMPFS,
328 .read_only = ro,
329 .options_malloc = o,
330 .flags = flags,
331 };
332
333 o = NULL((void*)0);
334 }
335
336 return 0;
337}
338
339static int append_static_mounts(MountEntry **p, const MountEntry *mounts, size_t n, bool_Bool ignore_protect) {
340 size_t i;
341
342 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 342, __PRETTY_FUNCTION__
); } while (0);
343 assert(mounts)do { if ((__builtin_expect(!!(!(mounts)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("mounts"), "../src/core/namespace.c", 343
, __PRETTY_FUNCTION__); } while (0);
344
345 /* Adds a list of static pre-defined entries */
346
347 for (i = 0; i < n; i++)
348 *((*p)++) = (MountEntry) {
349 .path_const = mount_entry_path(mounts+i),
350 .mode = mounts[i].mode,
351 .ignore = mounts[i].ignore || ignore_protect,
352 };
353
354 return 0;
355}
356
357static int append_protect_home(MountEntry **p, ProtectHome protect_home, bool_Bool ignore_protect) {
358 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 358, __PRETTY_FUNCTION__
); } while (0);
359
360 switch (protect_home) {
361
362 case PROTECT_HOME_NO:
363 return 0;
364
365 case PROTECT_HOME_READ_ONLY:
366 return append_static_mounts(p, protect_home_read_only_table, ELEMENTSOF(protect_home_read_only_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_home_read_only_table), typeof(&*(protect_home_read_only_table
))), sizeof(protect_home_read_only_table)/sizeof((protect_home_read_only_table
)[0]), ((void)0))), ignore_protect);
367
368 case PROTECT_HOME_TMPFS:
369 return append_static_mounts(p, protect_home_tmpfs_table, ELEMENTSOF(protect_home_tmpfs_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_home_tmpfs_table), typeof(&*(protect_home_tmpfs_table
))), sizeof(protect_home_tmpfs_table)/sizeof((protect_home_tmpfs_table
)[0]), ((void)0))), ignore_protect);
370
371 case PROTECT_HOME_YES:
372 return append_static_mounts(p, protect_home_yes_table, ELEMENTSOF(protect_home_yes_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_home_yes_table), typeof(&*(protect_home_yes_table
))), sizeof(protect_home_yes_table)/sizeof((protect_home_yes_table
)[0]), ((void)0))), ignore_protect);
373
374 default:
375 assert_not_reached("Unexpected ProtectHome= value")do { log_assert_failed_unreachable_realm(LOG_REALM_SYSTEMD, (
"Unexpected ProtectHome= value"), "../src/core/namespace.c", 375
, __PRETTY_FUNCTION__); } while (0);
376 }
377}
378
379static int append_protect_system(MountEntry **p, ProtectSystem protect_system, bool_Bool ignore_protect) {
380 assert(p)do { if ((__builtin_expect(!!(!(p)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("p"), "../src/core/namespace.c", 380, __PRETTY_FUNCTION__
); } while (0);
381
382 switch (protect_system) {
383
384 case PROTECT_SYSTEM_NO:
385 return 0;
386
387 case PROTECT_SYSTEM_STRICT:
388 return append_static_mounts(p, protect_system_strict_table, ELEMENTSOF(protect_system_strict_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_system_strict_table), typeof(&*(protect_system_strict_table
))), sizeof(protect_system_strict_table)/sizeof((protect_system_strict_table
)[0]), ((void)0))), ignore_protect);
389
390 case PROTECT_SYSTEM_YES:
391 return append_static_mounts(p, protect_system_yes_table, ELEMENTSOF(protect_system_yes_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_system_yes_table), typeof(&*(protect_system_yes_table
))), sizeof(protect_system_yes_table)/sizeof((protect_system_yes_table
)[0]), ((void)0))), ignore_protect);
392
393 case PROTECT_SYSTEM_FULL:
394 return append_static_mounts(p, protect_system_full_table, ELEMENTSOF(protect_system_full_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_system_full_table), typeof(&*(protect_system_full_table
))), sizeof(protect_system_full_table)/sizeof((protect_system_full_table
)[0]), ((void)0))), ignore_protect);
395
396 default:
397 assert_not_reached("Unexpected ProtectSystem= value")do { log_assert_failed_unreachable_realm(LOG_REALM_SYSTEMD, (
"Unexpected ProtectSystem= value"), "../src/core/namespace.c"
, 397, __PRETTY_FUNCTION__); } while (0);
398 }
399}
400
401static int mount_path_compare(const void *a, const void *b) {
402 const MountEntry *p = a, *q = b;
403 int d;
404
405 /* If the paths are not equal, then order prefixes first */
406 d = path_compare(mount_entry_path(p), mount_entry_path(q));
407 if (d != 0)
408 return d;
409
410 /* If the paths are equal, check the mode */
411 if (p->mode < q->mode)
412 return -1;
413 if (p->mode > q->mode)
414 return 1;
415
416 return 0;
417}
418
419static int prefix_where_needed(MountEntry *m, size_t n, const char *root_directory) {
420 size_t i;
421
422 /* Prefixes all paths in the bind mount table with the root directory if it is specified and the entry needs
423 * that. */
424
425 if (!root_directory)
426 return 0;
427
428 for (i = 0; i < n; i++) {
429 char *s;
430
431 if (m[i].has_prefix)
432 continue;
433
434 s = prefix_root(root_directory, mount_entry_path(m+i));
435 if (!s)
436 return -ENOMEM12;
437
438 free_and_replace(m[i].path_malloc, s)({ free(m[i].path_malloc); (m[i].path_malloc) = (s); (s) = ((
void*)0); 0; });
439 m[i].has_prefix = true1;
440 }
441
442 return 0;
443}
444
445static void drop_duplicates(MountEntry *m, size_t *n) {
446 MountEntry *f, *t, *previous;
447
448 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 448, __PRETTY_FUNCTION__
); } while (0);
449 assert(n)do { if ((__builtin_expect(!!(!(n)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("n"), "../src/core/namespace.c", 449, __PRETTY_FUNCTION__
); } while (0);
450
451 /* Drops duplicate entries. Expects that the array is properly ordered already. */
452
453 for (f = m, t = m, previous = NULL((void*)0); f < m + *n; f++) {
454
455 /* The first one wins (which is the one with the more restrictive mode), see mount_path_compare()
456 * above. Note that we only drop duplicates that haven't been mounted yet. */
457 if (previous &&
458 path_equal(mount_entry_path(f), mount_entry_path(previous)) &&
459 !f->applied && !previous->applied) {
460 log_debug("%s is duplicate.", mount_entry_path(f))({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 460, __func__, "%s is duplicate."
, mount_entry_path(f)) : -abs(_e); });
461 previous->read_only = previous->read_only || mount_entry_read_only(f); /* Propagate the read-only flag to the remaining entry */
462 mount_entry_done(f);
463 continue;
464 }
465
466 *t = *f;
467 previous = t;
468 t++;
469 }
470
471 *n = t - m;
472}
473
474static void drop_inaccessible(MountEntry *m, size_t *n) {
475 MountEntry *f, *t;
476 const char *clear = NULL((void*)0);
477
478 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 478, __PRETTY_FUNCTION__
); } while (0);
479 assert(n)do { if ((__builtin_expect(!!(!(n)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("n"), "../src/core/namespace.c", 479, __PRETTY_FUNCTION__
); } while (0);
480
481 /* Drops all entries obstructed by another entry further up the tree. Expects that the array is properly
482 * ordered already. */
483
484 for (f = m, t = m; f < m + *n; f++) {
485
486 /* If we found a path set for INACCESSIBLE earlier, and this entry has it as prefix we should drop
487 * it, as inaccessible paths really should drop the entire subtree. */
488 if (clear && path_startswith(mount_entry_path(f), clear)) {
489 log_debug("%s is masked by %s.", mount_entry_path(f), clear)({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 489, __func__, "%s is masked by %s."
, mount_entry_path(f), clear) : -abs(_e); });
490 mount_entry_done(f);
491 continue;
492 }
493
494 clear = f->mode == INACCESSIBLE ? mount_entry_path(f) : NULL((void*)0);
495
496 *t = *f;
497 t++;
498 }
499
500 *n = t - m;
501}
502
503static void drop_nop(MountEntry *m, size_t *n) {
504 MountEntry *f, *t;
505
506 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 506, __PRETTY_FUNCTION__
); } while (0);
507 assert(n)do { if ((__builtin_expect(!!(!(n)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("n"), "../src/core/namespace.c", 507, __PRETTY_FUNCTION__
); } while (0);
508
509 /* Drops all entries which have an immediate parent that has the same type, as they are redundant. Assumes the
510 * list is ordered by prefixes. */
511
512 for (f = m, t = m; f < m + *n; f++) {
513
514 /* Only suppress such subtrees for READONLY and READWRITE entries */
515 if (IN_SET(f->mode, READONLY, READWRITE)({ _Bool _found = 0; static __attribute__ ((unused)) char _static_assert__macros_need_to_be_extended
[20 - sizeof((int[]){READONLY, READWRITE})/sizeof(int)]; switch
(f->mode) { case READONLY: case READWRITE: _found = 1; break
; default: break; } _found; })) {
516 MountEntry *p;
517 bool_Bool found = false0;
518
519 /* Now let's find the first parent of the entry we are looking at. */
520 for (p = t-1; p >= m; p--) {
521 if (path_startswith(mount_entry_path(f), mount_entry_path(p))) {
522 found = true1;
523 break;
524 }
525 }
526
527 /* We found it, let's see if it's the same mode, if so, we can drop this entry */
528 if (found && p->mode == f->mode) {
529 log_debug("%s is redundant by %s", mount_entry_path(f), mount_entry_path(p))({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 529, __func__, "%s is redundant by %s"
, mount_entry_path(f), mount_entry_path(p)) : -abs(_e); });
530 mount_entry_done(f);
531 continue;
532 }
533 }
534
535 *t = *f;
536 t++;
537 }
538
539 *n = t - m;
540}
541
542static void drop_outside_root(const char *root_directory, MountEntry *m, size_t *n) {
543 MountEntry *f, *t;
544
545 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 545, __PRETTY_FUNCTION__
); } while (0);
546 assert(n)do { if ((__builtin_expect(!!(!(n)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("n"), "../src/core/namespace.c", 546, __PRETTY_FUNCTION__
); } while (0);
547
548 /* Nothing to do */
549 if (!root_directory)
550 return;
551
552 /* Drops all mounts that are outside of the root directory. */
553
554 for (f = m, t = m; f < m + *n; f++) {
555
556 if (!path_startswith(mount_entry_path(f), root_directory)) {
557 log_debug("%s is outside of root directory.", mount_entry_path(f))({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 557, __func__, "%s is outside of root directory."
, mount_entry_path(f)) : -abs(_e); });
558 mount_entry_done(f);
559 continue;
560 }
561
562 *t = *f;
563 t++;
564 }
565
566 *n = t - m;
567}
568
569static int clone_device_node(const char *d, const char *temporary_mount, bool_Bool *make_devnode) {
570 const char *dn;
571 struct stat st;
572 int r;
573
574 if (stat(d, &st) < 0) {
575 if (errno(*__errno_location ()) == ENOENT2)
576 return -ENXIO6;
577 return -errno(*__errno_location ());
578 }
579
580 if (!S_ISBLK(st.st_mode)((((st.st_mode)) & 0170000) == (0060000)) &&
581 !S_ISCHR(st.st_mode)((((st.st_mode)) & 0170000) == (0020000)))
582 return -EINVAL22;
583
584 if (st.st_rdev == 0)
585 return -ENXIO6;
586
587 dn = strjoina(temporary_mount, d)({ const char *_appendees_[] = { temporary_mount, d }; char *
_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ = 0; _i_ <
__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
588
589 if (*make_devnode) {
590 mac_selinux_create_file_prepare(d, st.st_mode);
591 r = mknod(dn, st.st_mode, st.st_rdev);
592 mac_selinux_create_file_clear();
593
594 if (r == 0)
595 return 0;
596 if (errno(*__errno_location ()) != EPERM1)
597 return log_debug_errno(errno, "mknod failed for %s: %m", d)({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 597, __func__
, "mknod failed for %s: %m", d) : -abs(_e); });
598
599 *make_devnode = false0;
600 }
601
602 /* We're about to fallback to bind-mounting the device
603 * node. So create a dummy bind-mount target. */
604 mac_selinux_create_file_prepare(d, 0);
605 r = mknod(dn, S_IFREG0100000, 0);
606 mac_selinux_create_file_clear();
607
608 if (r < 0 && errno(*__errno_location ()) != EEXIST17)
609 return log_debug_errno(errno, "mknod fallback failed for %s: %m", d)({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 609, __func__
, "mknod fallback failed for %s: %m", d) : -abs(_e); });
610
611 /* Fallback to bind-mounting:
612 * The assumption here is that all used device nodes carry standard
613 * properties. Specifically, the devices nodes we bind-mount should
614 * either be owned by root:root or root:tty (e.g. /dev/tty, /dev/ptmx)
615 * and should not carry ACLs. */
616 if (mount(d, dn, NULL((void*)0), MS_BIND4096, NULL((void*)0)) < 0)
617 return log_debug_errno(errno, "mount failed for %s: %m", d)({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 617, __func__
, "mount failed for %s: %m", d) : -abs(_e); });
618
619 return 0;
620}
621
622static int mount_private_dev(MountEntry *m) {
623 static const char devnodes[] =
624 "/dev/null\0"
625 "/dev/zero\0"
626 "/dev/full\0"
627 "/dev/random\0"
628 "/dev/urandom\0"
629 "/dev/tty\0";
630
631 char temporary_mount[] = "/tmp/namespace-dev-XXXXXX";
632 const char *d, *dev = NULL((void*)0), *devpts = NULL((void*)0), *devshm = NULL((void*)0), *devhugepages = NULL((void*)0), *devmqueue = NULL((void*)0), *devlog = NULL((void*)0), *devptmx = NULL((void*)0);
633 bool_Bool can_mknod = true1;
634 _cleanup_umask___attribute__((cleanup(umaskp))) mode_t u;
635 int r;
636
637 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 637, __PRETTY_FUNCTION__
); } while (0);
638
639 u = umask(0000);
640
641 if (!mkdtemp(temporary_mount))
642 return -errno(*__errno_location ());
643
644 dev = strjoina(temporary_mount, "/dev")({ const char *_appendees_[] = { temporary_mount, "/dev" }; char
*_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ = 0; _i_ <
__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
645 (void) mkdir(dev, 0755);
646 if (mount("tmpfs", dev, "tmpfs", DEV_MOUNT_OPTIONS(2|(1<<24)|8), "mode=755") < 0) {
647 r = -errno(*__errno_location ());
648 goto fail;
649 }
650
651 devpts = strjoina(temporary_mount, "/dev/pts")({ const char *_appendees_[] = { temporary_mount, "/dev/pts" }
; char *_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ = 0
; _i_ < __extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
652 (void) mkdir(devpts, 0755);
653 if (mount("/dev/pts", devpts, NULL((void*)0), MS_BIND4096, NULL((void*)0)) < 0) {
654 r = -errno(*__errno_location ());
655 goto fail;
656 }
657
658 /* /dev/ptmx can either be a device node or a symlink to /dev/pts/ptmx
659 * when /dev/ptmx a device node, /dev/pts/ptmx has 000 permissions making it inaccessible
660 * thus, in that case make a clone
661 *
662 * in nspawn and other containers it will be a symlink, in that case make it a symlink
663 */
664 r = is_symlink("/dev/ptmx");
665 if (r < 0)
666 goto fail;
667 if (r > 0) {
668 devptmx = strjoina(temporary_mount, "/dev/ptmx")({ const char *_appendees_[] = { temporary_mount, "/dev/ptmx"
}; char *_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ =
0; _i_ < __extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
669 if (symlink("pts/ptmx", devptmx) < 0) {
670 r = -errno(*__errno_location ());
671 goto fail;
672 }
673 } else {
674 r = clone_device_node("/dev/ptmx", temporary_mount, &can_mknod);
675 if (r < 0)
676 goto fail;
677 }
678
679 devshm = strjoina(temporary_mount, "/dev/shm")({ const char *_appendees_[] = { temporary_mount, "/dev/shm" }
; char *_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ = 0
; _i_ < __extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
680 (void) mkdir(devshm, 0755);
681 r = mount("/dev/shm", devshm, NULL((void*)0), MS_BIND4096, NULL((void*)0));
682 if (r < 0) {
683 r = -errno(*__errno_location ());
684 goto fail;
685 }
686
687 devmqueue = strjoina(temporary_mount, "/dev/mqueue")({ const char *_appendees_[] = { temporary_mount, "/dev/mqueue"
}; char *_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ =
0; _i_ < __extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
688 (void) mkdir(devmqueue, 0755);
689 (void) mount("/dev/mqueue", devmqueue, NULL((void*)0), MS_BIND4096, NULL((void*)0));
690
691 devhugepages = strjoina(temporary_mount, "/dev/hugepages")({ const char *_appendees_[] = { temporary_mount, "/dev/hugepages"
}; char *_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ =
0; _i_ < __extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
692 (void) mkdir(devhugepages, 0755);
693 (void) mount("/dev/hugepages", devhugepages, NULL((void*)0), MS_BIND4096, NULL((void*)0));
694
695 devlog = strjoina(temporary_mount, "/dev/log")({ const char *_appendees_[] = { temporary_mount, "/dev/log" }
; char *_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ = 0
; _i_ < __extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
696 (void) symlink("/run/systemd/journal/dev-log", devlog);
697
698 NULSTR_FOREACH(d, devnodes)for ((d) = (devnodes); (d) && *(d); (d) = strchr((d),
0)+1) {
699 r = clone_device_node(d, temporary_mount, &can_mknod);
700 /* ENXIO means the the *source* is not a device file, skip creation in that case */
701 if (r < 0 && r != -ENXIO6)
702 goto fail;
703 }
704
705 dev_setup(temporary_mount, UID_INVALID((uid_t) -1), GID_INVALID((gid_t) -1));
706
707 /* Create the /dev directory if missing. It is more likely to be
708 * missing when the service is started with RootDirectory. This is
709 * consistent with mount units creating the mount points when missing.
710 */
711 (void) mkdir_p_label(mount_entry_path(m), 0755);
712
713 /* Unmount everything in old /dev */
714 umount_recursive(mount_entry_path(m), 0);
715 if (mount(dev, mount_entry_path(m), NULL((void*)0), MS_MOVE8192, NULL((void*)0)) < 0) {
716 r = -errno(*__errno_location ());
717 goto fail;
718 }
719
720 rmdir(dev);
721 rmdir(temporary_mount);
722
723 return 0;
724
725fail:
726 if (devpts)
727 umount(devpts);
728
729 if (devshm)
730 umount(devshm);
731
732 if (devhugepages)
733 umount(devhugepages);
734
735 if (devmqueue)
736 umount(devmqueue);
737
738 umount(dev);
739 rmdir(dev);
740 rmdir(temporary_mount);
741
742 return r;
743}
744
745static int mount_bind_dev(const MountEntry *m) {
746 int r;
747
748 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 748, __PRETTY_FUNCTION__
); } while (0);
749
750 /* Implements the little brother of mount_private_dev(): simply bind mounts the host's /dev into the service's
751 * /dev. This is only used when RootDirectory= is set. */
752
753 (void) mkdir_p_label(mount_entry_path(m), 0755);
754
755 r = path_is_mount_point(mount_entry_path(m), NULL((void*)0), 0);
756 if (r < 0)
757 return log_debug_errno(r, "Unable to determine whether /dev is already mounted: %m")({ int _level = ((7)), _e = ((r)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 757, __func__, "Unable to determine whether /dev is already mounted: %m"
) : -abs(_e); });
758 if (r > 0) /* make this a NOP if /dev is already a mount point */
759 return 0;
760
761 if (mount("/dev", mount_entry_path(m), NULL((void*)0), MS_BIND4096|MS_REC16384, NULL((void*)0)) < 0)
762 return log_debug_errno(errno, "Failed to bind mount %s: %m", mount_entry_path(m))({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 762, __func__
, "Failed to bind mount %s: %m", mount_entry_path(m)) : -abs(
_e); });
763
764 return 1;
765}
766
767static int mount_sysfs(const MountEntry *m) {
768 int r;
769
770 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 770, __PRETTY_FUNCTION__
); } while (0);
771
772 (void) mkdir_p_label(mount_entry_path(m), 0755);
773
774 r = path_is_mount_point(mount_entry_path(m), NULL((void*)0), 0);
775 if (r < 0)
776 return log_debug_errno(r, "Unable to determine whether /sys is already mounted: %m")({ int _level = ((7)), _e = ((r)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 776, __func__, "Unable to determine whether /sys is already mounted: %m"
) : -abs(_e); });
777 if (r > 0) /* make this a NOP if /sys is already a mount point */
778 return 0;
779
780 /* Bind mount the host's version so that we get all child mounts of it, too. */
781 if (mount("/sys", mount_entry_path(m), NULL((void*)0), MS_BIND4096|MS_REC16384, NULL((void*)0)) < 0)
782 return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m))({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 782, __func__
, "Failed to mount %s: %m", mount_entry_path(m)) : -abs(_e); }
);
783
784 return 1;
785}
786
787static int mount_procfs(const MountEntry *m) {
788 int r;
789
790 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 790, __PRETTY_FUNCTION__
); } while (0);
791
792 (void) mkdir_p_label(mount_entry_path(m), 0755);
793
794 r = path_is_mount_point(mount_entry_path(m), NULL((void*)0), 0);
795 if (r < 0)
796 return log_debug_errno(r, "Unable to determine whether /proc is already mounted: %m")({ int _level = ((7)), _e = ((r)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 796, __func__, "Unable to determine whether /proc is already mounted: %m"
) : -abs(_e); });
797 if (r > 0) /* make this a NOP if /proc is already a mount point */
798 return 0;
799
800 /* Mount a new instance, so that we get the one that matches our user namespace, if we are running in one */
801 if (mount("proc", mount_entry_path(m), "proc", MS_NOSUID2|MS_NOEXEC8|MS_NODEV4, NULL((void*)0)) < 0)
802 return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m))({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 802, __func__
, "Failed to mount %s: %m", mount_entry_path(m)) : -abs(_e); }
);
803
804 return 1;
805}
806
807static int mount_tmpfs(const MountEntry *m) {
808 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 808, __PRETTY_FUNCTION__
); } while (0);
809
810 /* First, get rid of everything that is below if there is anything. Then, overmount with our new tmpfs */
811
812 (void) mkdir_p_label(mount_entry_path(m), 0755);
813 (void) umount_recursive(mount_entry_path(m), 0);
814
815 if (mount("tmpfs", mount_entry_path(m), "tmpfs", m->flags, mount_entry_options(m)) < 0)
816 return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m))({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 816, __func__
, "Failed to mount %s: %m", mount_entry_path(m)) : -abs(_e); }
);
817
818 return 1;
819}
820
821static int follow_symlink(
822 const char *root_directory,
823 MountEntry *m) {
824
825 _cleanup_free___attribute__((cleanup(freep))) char *target = NULL((void*)0);
826 int r;
827
828 /* Let's chase symlinks, but only one step at a time. That's because depending where the symlink points we
829 * might need to change the order in which we mount stuff. Hence: let's normalize piecemeal, and do one step at
830 * a time by specifying CHASE_STEP. This function returns 0 if we resolved one step, and > 0 if we reached the
831 * end and already have a fully normalized name. */
832
833 r = chase_symlinks(mount_entry_path(m), root_directory, CHASE_STEP|CHASE_NONEXISTENT, &target);
834 if (r < 0)
835 return log_debug_errno(r, "Failed to chase symlinks '%s': %m", mount_entry_path(m))({ int _level = ((7)), _e = ((r)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 835, __func__, "Failed to chase symlinks '%s': %m"
, mount_entry_path(m)) : -abs(_e); });
836 if (r > 0) /* Reached the end, nothing more to resolve */
837 return 1;
838
839 if (m->n_followed >= CHASE_SYMLINKS_MAX32) { /* put a boundary on things */
840 log_debug("Symlink loop on '%s'.", mount_entry_path(m))({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 840, __func__, "Symlink loop on '%s'."
, mount_entry_path(m)) : -abs(_e); });
841 return -ELOOP40;
842 }
843
844 log_debug("Followed mount entry path symlink %s → %s.", mount_entry_path(m), target)({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 844, __func__, "Followed mount entry path symlink %s → %s."
, mount_entry_path(m), target) : -abs(_e); });
845
846 free_and_replace(m->path_malloc, target)({ free(m->path_malloc); (m->path_malloc) = (target); (
target) = ((void*)0); 0; });
847 m->has_prefix = true1;
848
849 m->n_followed ++;
850
851 return 0;
852}
853
854static int apply_mount(
855 const char *root_directory,
856 MountEntry *m) {
857
858 bool_Bool rbind = true1, make = false0;
859 const char *what;
860 int r;
861
862 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 862, __PRETTY_FUNCTION__
); } while (0);
863
864 log_debug("Applying namespace mount on %s", mount_entry_path(m))({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 864, __func__, "Applying namespace mount on %s"
, mount_entry_path(m)) : -abs(_e); });
865
866 switch (m->mode) {
867
868 case INACCESSIBLE: {
869 struct stat target;
870
871 /* First, get rid of everything that is below if there
872 * is anything... Then, overmount it with an
873 * inaccessible path. */
874 (void) umount_recursive(mount_entry_path(m), 0);
875
876 if (lstat(mount_entry_path(m), &target) < 0) {
877 if (errno(*__errno_location ()) == ENOENT2 && m->ignore)
878 return 0;
879
880 return log_debug_errno(errno, "Failed to lstat() %s to determine what to mount over it: %m", mount_entry_path(m))({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 880, __func__
, "Failed to lstat() %s to determine what to mount over it: %m"
, mount_entry_path(m)) : -abs(_e); });
881 }
882
883 what = mode_to_inaccessible_node(target.st_mode);
884 if (!what) {
885 log_debug("File type not supported for inaccessible mounts. Note that symlinks are not allowed")({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 885, __func__, "File type not supported for inaccessible mounts. Note that symlinks are not allowed"
) : -abs(_e); });
886 return -ELOOP40;
887 }
888 break;
889 }
890
891 case READONLY:
892 case READWRITE:
893 r = path_is_mount_point(mount_entry_path(m), root_directory, 0);
894 if (r == -ENOENT2 && m->ignore)
895 return 0;
896 if (r < 0)
897 return log_debug_errno(r, "Failed to determine whether %s is already a mount point: %m", mount_entry_path(m))({ int _level = ((7)), _e = ((r)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 897, __func__, "Failed to determine whether %s is already a mount point: %m"
, mount_entry_path(m)) : -abs(_e); });
898 if (r > 0) /* Nothing to do here, it is already a mount. We just later toggle the MS_RDONLY bit for the mount point if needed. */
899 return 0;
900 /* This isn't a mount point yet, let's make it one. */
901 what = mount_entry_path(m);
902 break;
903
904 case BIND_MOUNT:
905 rbind = false0;
906
907 _fallthrough_;
908 case BIND_MOUNT_RECURSIVE: {
909 _cleanup_free___attribute__((cleanup(freep))) char *chased = NULL((void*)0);
910
911 /* Since mount() will always follow symlinks we chase the symlinks on our own first. Note that bind
912 * mount source paths are always relative to the host root, hence we pass NULL as root directory to
913 * chase_symlinks() here. */
914
915 r = chase_symlinks(mount_entry_source(m), NULL((void*)0), CHASE_TRAIL_SLASH, &chased);
916 if (r == -ENOENT2 && m->ignore) {
917 log_debug_errno(r, "Path %s does not exist, ignoring.", mount_entry_source(m))({ int _level = ((7)), _e = ((r)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 917, __func__, "Path %s does not exist, ignoring."
, mount_entry_source(m)) : -abs(_e); });
918 return 0;
919 }
920 if (r < 0)
921 return log_debug_errno(r, "Failed to follow symlinks on %s: %m", mount_entry_source(m))({ int _level = ((7)), _e = ((r)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 921, __func__, "Failed to follow symlinks on %s: %m"
, mount_entry_source(m)) : -abs(_e); });
922
923 log_debug("Followed source symlinks %s → %s.", mount_entry_source(m), chased)({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 923, __func__, "Followed source symlinks %s → %s."
, mount_entry_source(m), chased) : -abs(_e); });
924
925 free_and_replace(m->source_malloc, chased)({ free(m->source_malloc); (m->source_malloc) = (chased
); (chased) = ((void*)0); 0; });
926
927 what = mount_entry_source(m);
928 make = true1;
929 break;
930 }
931
932 case EMPTY_DIR:
933 case TMPFS:
934 return mount_tmpfs(m);
935
936 case PRIVATE_TMP:
937 what = mount_entry_source(m);
938 make = true1;
939 break;
940
941 case PRIVATE_DEV:
942 return mount_private_dev(m);
943
944 case BIND_DEV:
945 return mount_bind_dev(m);
946
947 case SYSFS:
948 return mount_sysfs(m);
949
950 case PROCFS:
951 return mount_procfs(m);
952
953 default:
954 assert_not_reached("Unknown mode")do { log_assert_failed_unreachable_realm(LOG_REALM_SYSTEMD, (
"Unknown mode"), "../src/core/namespace.c", 954, __PRETTY_FUNCTION__
); } while (0);
955 }
956
957 assert(what)do { if ((__builtin_expect(!!(!(what)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("what"), "../src/core/namespace.c", 957,
__PRETTY_FUNCTION__); } while (0);
958
959 if (mount(what, mount_entry_path(m), NULL((void*)0), MS_BIND4096|(rbind ? MS_REC16384 : 0), NULL((void*)0)) < 0) {
960 bool_Bool try_again = false0;
961 r = -errno(*__errno_location ());
962
963 if (r == -ENOENT2 && make) {
964 struct stat st;
965
966 /* Hmm, either the source or the destination are missing. Let's see if we can create the destination, then try again */
967
968 if (stat(what, &st) < 0)
969 log_debug_errno(errno, "Mount point source '%s' is not accessible: %m", what)({ int _level = ((7)), _e = (((*__errno_location ()))), _realm
= (LOG_REALM_SYSTEMD); (log_get_max_level_realm(_realm) >=
((_level) & 0x07)) ? log_internal_realm(((_realm) <<
10 | (_level)), _e, "../src/core/namespace.c", 969, __func__
, "Mount point source '%s' is not accessible: %m", what) : -abs
(_e); });
970 else {
971 int q;
972
973 (void) mkdir_parents(mount_entry_path(m), 0755);
974
975 if (S_ISDIR(st.st_mode)((((st.st_mode)) & 0170000) == (0040000)))
976 q = mkdir(mount_entry_path(m), 0755) < 0 ? -errno(*__errno_location ()) : 0;
977 else
978 q = touch(mount_entry_path(m));
979
980 if (q < 0)
981 log_debug_errno(q, "Failed to create destination mount point node '%s': %m", mount_entry_path(m))({ int _level = ((7)), _e = ((q)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 981, __func__, "Failed to create destination mount point node '%s': %m"
, mount_entry_path(m)) : -abs(_e); });
982 else
983 try_again = true1;
984 }
985 }
986
987 if (try_again) {
988 if (mount(what, mount_entry_path(m), NULL((void*)0), MS_BIND4096|(rbind ? MS_REC16384 : 0), NULL((void*)0)) < 0)
989 r = -errno(*__errno_location ());
990 else
991 r = 0;
992 }
993
994 if (r < 0)
995 return log_debug_errno(r, "Failed to mount %s to %s: %m", what, mount_entry_path(m))({ int _level = ((7)), _e = ((r)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 995, __func__, "Failed to mount %s to %s: %m"
, what, mount_entry_path(m)) : -abs(_e); });
996 }
997
998 log_debug("Successfully mounted %s to %s", what, mount_entry_path(m))({ int _level = (((7))), _e = ((0)), _realm = (LOG_REALM_SYSTEMD
); (log_get_max_level_realm(_realm) >= ((_level) & 0x07
)) ? log_internal_realm(((_realm) << 10 | (_level)), _e
, "../src/core/namespace.c", 998, __func__, "Successfully mounted %s to %s"
, what, mount_entry_path(m)) : -abs(_e); });
999 return 0;
1000}
1001
1002static int make_read_only(const MountEntry *m, char **blacklist, FILE *proc_self_mountinfo) {
1003 int r = 0;
1004
1005 assert(m)do { if ((__builtin_expect(!!(!(m)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("m"), "../src/core/namespace.c", 1005, __PRETTY_FUNCTION__
); } while (0);
1006 assert(proc_self_mountinfo)do { if ((__builtin_expect(!!(!(proc_self_mountinfo)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("proc_self_mountinfo"), "../src/core/namespace.c"
, 1006, __PRETTY_FUNCTION__); } while (0);
1007
1008 if (mount_entry_read_only(m)) {
1009 if (IN_SET(m->mode, EMPTY_DIR, TMPFS)({ _Bool _found = 0; static __attribute__ ((unused)) char _static_assert__macros_need_to_be_extended
[20 - sizeof((int[]){EMPTY_DIR, TMPFS})/sizeof(int)]; switch(
m->mode) { case EMPTY_DIR: case TMPFS: _found = 1; break; default
: break; } _found; })) {
1010 /* Make superblock readonly */
1011 if (mount(NULL((void*)0), mount_entry_path(m), NULL((void*)0), MS_REMOUNT32 | MS_RDONLY1 | m->flags, mount_entry_options(m)) < 0)
1012 r = -errno(*__errno_location ());
1013 } else
1014 r = bind_remount_recursive_with_mountinfo(mount_entry_path(m), true1, blacklist, proc_self_mountinfo);
1015 } else if (m->mode == PRIVATE_DEV) {
1016 /* Superblock can be readonly but the submounts can't */
1017 if (mount(NULL((void*)0), mount_entry_path(m), NULL((void*)0), MS_REMOUNT32|DEV_MOUNT_OPTIONS(2|(1<<24)|8)|MS_RDONLY1, NULL((void*)0)) < 0)
1018 r = -errno(*__errno_location ());
1019 } else
1020 return 0;
1021
1022 /* Not that we only turn on the MS_RDONLY flag here, we never turn it off. Something that was marked read-only
1023 * already stays this way. This improves compatibility with container managers, where we won't attempt to undo
1024 * read-only mounts already applied. */
1025
1026 if (r == -ENOENT2 && m->ignore)
1027 r = 0;
1028
1029 return r;
1030}
1031
1032static bool_Bool namespace_info_mount_apivfs(const char *root_directory, const NamespaceInfo *ns_info) {
1033 assert(ns_info)do { if ((__builtin_expect(!!(!(ns_info)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("ns_info"), "../src/core/namespace.c", 1033
, __PRETTY_FUNCTION__); } while (0);
1034
1035 /*
1036 * ProtectControlGroups= and ProtectKernelTunables= imply MountAPIVFS=,
1037 * since to protect the API VFS mounts, they need to be around in the
1038 * first place... and RootDirectory= or RootImage= need to be set.
1039 */
1040
1041 /* root_directory should point to a mount point */
1042 return root_directory &&
1043 (ns_info->mount_apivfs ||
1044 ns_info->protect_control_groups ||
1045 ns_info->protect_kernel_tunables);
1046}
1047
1048static size_t namespace_calculate_mounts(
1049 const char* root_directory,
1050 const NamespaceInfo *ns_info,
1051 char** read_write_paths,
1052 char** read_only_paths,
1053 char** inaccessible_paths,
1054 char** empty_directories,
1055 size_t n_bind_mounts,
1056 size_t n_temporary_filesystems,
1057 const char* tmp_dir,
1058 const char* var_tmp_dir,
1059 ProtectHome protect_home,
1060 ProtectSystem protect_system) {
1061
1062 size_t protect_home_cnt;
1063 size_t protect_system_cnt =
1064 (protect_system == PROTECT_SYSTEM_STRICT ?
1065 ELEMENTSOF(protect_system_strict_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_system_strict_table), typeof(&*(protect_system_strict_table
))), sizeof(protect_system_strict_table)/sizeof((protect_system_strict_table
)[0]), ((void)0))) :
1066 ((protect_system == PROTECT_SYSTEM_FULL) ?
1067 ELEMENTSOF(protect_system_full_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_system_full_table), typeof(&*(protect_system_full_table
))), sizeof(protect_system_full_table)/sizeof((protect_system_full_table
)[0]), ((void)0))) :
1068 ((protect_system == PROTECT_SYSTEM_YES) ?
1069 ELEMENTSOF(protect_system_yes_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_system_yes_table), typeof(&*(protect_system_yes_table
))), sizeof(protect_system_yes_table)/sizeof((protect_system_yes_table
)[0]), ((void)0))) : 0)));
1070
1071 protect_home_cnt =
1072 (protect_home == PROTECT_HOME_YES ?
1073 ELEMENTSOF(protect_home_yes_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_home_yes_table), typeof(&*(protect_home_yes_table
))), sizeof(protect_home_yes_table)/sizeof((protect_home_yes_table
)[0]), ((void)0))) :
1074 ((protect_home == PROTECT_HOME_READ_ONLY) ?
1075 ELEMENTSOF(protect_home_read_only_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_home_read_only_table), typeof(&*(protect_home_read_only_table
))), sizeof(protect_home_read_only_table)/sizeof((protect_home_read_only_table
)[0]), ((void)0))) :
1076 ((protect_home == PROTECT_HOME_TMPFS) ?
1077 ELEMENTSOF(protect_home_tmpfs_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_home_tmpfs_table), typeof(&*(protect_home_tmpfs_table
))), sizeof(protect_home_tmpfs_table)/sizeof((protect_home_tmpfs_table
)[0]), ((void)0))) : 0)));
1078
1079 return !!tmp_dir + !!var_tmp_dir +
1080 strv_length(read_write_paths) +
1081 strv_length(read_only_paths) +
1082 strv_length(inaccessible_paths) +
1083 strv_length(empty_directories) +
1084 n_bind_mounts +
1085 n_temporary_filesystems +
1086 ns_info->private_dev +
1087 (ns_info->protect_kernel_tunables ? ELEMENTSOF(protect_kernel_tunables_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_kernel_tunables_table), typeof(&*(protect_kernel_tunables_table
))), sizeof(protect_kernel_tunables_table)/sizeof((protect_kernel_tunables_table
)[0]), ((void)0))) : 0) +
1088 (ns_info->protect_control_groups ? 1 : 0) +
1089 (ns_info->protect_kernel_modules ? ELEMENTSOF(protect_kernel_modules_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_kernel_modules_table), typeof(&*(protect_kernel_modules_table
))), sizeof(protect_kernel_modules_table)/sizeof((protect_kernel_modules_table
)[0]), ((void)0))) : 0) +
1090 protect_home_cnt + protect_system_cnt +
1091 (namespace_info_mount_apivfs(root_directory, ns_info) ? ELEMENTSOF(apivfs_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(apivfs_table), typeof(&*(apivfs_table))), sizeof(
apivfs_table)/sizeof((apivfs_table)[0]), ((void)0))) : 0);
1092}
1093
1094static void normalize_mounts(const char *root_directory, MountEntry *mounts, size_t *n_mounts) {
1095 assert(n_mounts)do { if ((__builtin_expect(!!(!(n_mounts)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("n_mounts"), "../src/core/namespace.c", 1095
, __PRETTY_FUNCTION__); } while (0);
1096 assert(mounts || *n_mounts == 0)do { if ((__builtin_expect(!!(!(mounts || *n_mounts == 0)),0)
)) log_assert_failed_realm(LOG_REALM_SYSTEMD, ("mounts || *n_mounts == 0"
), "../src/core/namespace.c", 1096, __PRETTY_FUNCTION__); } while
(0);
1097
1098 qsort_safe(mounts, *n_mounts, sizeof(MountEntry), mount_path_compare);
1099
1100 drop_duplicates(mounts, n_mounts);
1101 drop_outside_root(root_directory, mounts, n_mounts);
1102 drop_inaccessible(mounts, n_mounts);
1103 drop_nop(mounts, n_mounts);
1104}
1105
1106int setup_namespace(
1107 const char* root_directory,
1108 const char* root_image,
1109 const NamespaceInfo *ns_info,
1110 char** read_write_paths,
1111 char** read_only_paths,
1112 char** inaccessible_paths,
1113 char** empty_directories,
1114 const BindMount *bind_mounts,
1115 size_t n_bind_mounts,
1116 const TemporaryFileSystem *temporary_filesystems,
1117 size_t n_temporary_filesystems,
1118 const char* tmp_dir,
1119 const char* var_tmp_dir,
1120 ProtectHome protect_home,
1121 ProtectSystem protect_system,
1122 unsigned long mount_flags,
1123 DissectImageFlags dissect_image_flags) {
1124
1125 _cleanup_(loop_device_unrefp)__attribute__((cleanup(loop_device_unrefp))) LoopDevice *loop_device = NULL((void*)0);
1126 _cleanup_(decrypted_image_unrefp)__attribute__((cleanup(decrypted_image_unrefp))) DecryptedImage *decrypted_image = NULL((void*)0);
1127 _cleanup_(dissected_image_unrefp)__attribute__((cleanup(dissected_image_unrefp))) DissectedImage *dissected_image = NULL((void*)0);
1128 _cleanup_free___attribute__((cleanup(freep))) void *root_hash = NULL((void*)0);
1129 MountEntry *m, *mounts = NULL((void*)0);
1130 size_t root_hash_size = 0;
1131 const char *root;
1132 size_t n_mounts;
1133 bool_Bool make_slave;
1134 bool_Bool require_prefix = false0;
1135 int r = 0;
1136
1137 assert(ns_info)do { if ((__builtin_expect(!!(!(ns_info)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("ns_info"), "../src/core/namespace.c", 1137
, __PRETTY_FUNCTION__); } while (0);
1138
1139 if (mount_flags == 0)
1140 mount_flags = MS_SHARED(1<<20);
1141
1142 if (root_image) {
1143 dissect_image_flags |= DISSECT_IMAGE_REQUIRE_ROOT;
1144
1145 if (protect_system == PROTECT_SYSTEM_STRICT &&
1146 protect_home != PROTECT_HOME_NO &&
1147 strv_isempty(read_write_paths))
1148 dissect_image_flags |= DISSECT_IMAGE_READ_ONLY;
1149
1150 r = loop_device_make_by_path(root_image,
1151 dissect_image_flags & DISSECT_IMAGE_READ_ONLY ? O_RDONLY00 : O_RDWR02,
1152 &loop_device);
1153 if (r < 0)
1154 return r;
1155
1156 r = root_hash_load(root_image, &root_hash, &root_hash_size);
1157 if (r < 0)
1158 return r;
1159
1160 r = dissect_image(loop_device->fd, root_hash, root_hash_size, dissect_image_flags, &dissected_image);
1161 if (r < 0)
1162 return r;
1163
1164 r = dissected_image_decrypt(dissected_image, NULL((void*)0), root_hash, root_hash_size, dissect_image_flags, &decrypted_image);
1165 if (r < 0)
1166 return r;
1167 }
1168
1169 if (root_directory)
1170 root = root_directory;
1171 else {
1172 /* Always create the mount namespace in a temporary directory, instead of operating
1173 * directly in the root. The temporary directory prevents any mounts from being
1174 * potentially obscured my other mounts we already applied.
1175 * We use the same mount point for all images, which is safe, since they all live
1176 * in their own namespaces after all, and hence won't see each other. */
1177
1178 root = "/run/systemd/unit-root";
1179 (void) mkdir_label(root, 0700);
1180 require_prefix = true1;
1181 }
1182
1183 n_mounts = namespace_calculate_mounts(
1184 root,
1185 ns_info,
1186 read_write_paths,
1187 read_only_paths,
1188 inaccessible_paths,
1189 empty_directories,
1190 n_bind_mounts,
1191 n_temporary_filesystems,
1192 tmp_dir, var_tmp_dir,
1193 protect_home, protect_system);
1194
1195 /* Set mount slave mode */
1196 make_slave = root || n_mounts > 0 || ns_info->private_mounts;
1197
1198 if (n_mounts > 0) {
1199 m = mounts = (MountEntry *) alloca0(n_mounts * sizeof(MountEntry))({ char *_new_; size_t _len_ = n_mounts * sizeof(MountEntry);
_new_ = __builtin_alloca (_len_); (void *) memset(_new_, 0, _len_
); });
1200 r = append_access_mounts(&m, read_write_paths, READWRITE, require_prefix);
1201 if (r < 0)
1202 goto finish;
1203
1204 r = append_access_mounts(&m, read_only_paths, READONLY, require_prefix);
1205 if (r < 0)
1206 goto finish;
1207
1208 r = append_access_mounts(&m, inaccessible_paths, INACCESSIBLE, require_prefix);
1209 if (r < 0)
1210 goto finish;
1211
1212 r = append_empty_dir_mounts(&m, empty_directories);
1213 if (r < 0)
1214 goto finish;
1215
1216 r = append_bind_mounts(&m, bind_mounts, n_bind_mounts);
1217 if (r < 0)
1218 goto finish;
1219
1220 r = append_tmpfs_mounts(&m, temporary_filesystems, n_temporary_filesystems);
1221 if (r < 0)
1222 goto finish;
1223
1224 if (tmp_dir) {
1225 *(m++) = (MountEntry) {
1226 .path_const = "/tmp",
1227 .mode = PRIVATE_TMP,
1228 .source_const = tmp_dir,
1229 };
1230 }
1231
1232 if (var_tmp_dir) {
1233 *(m++) = (MountEntry) {
1234 .path_const = "/var/tmp",
1235 .mode = PRIVATE_TMP,
1236 .source_const = var_tmp_dir,
1237 };
1238 }
1239
1240 if (ns_info->private_dev) {
1241 *(m++) = (MountEntry) {
1242 .path_const = "/dev",
1243 .mode = PRIVATE_DEV,
1244 };
1245 }
1246
1247 if (ns_info->protect_kernel_tunables) {
1248 r = append_static_mounts(&m, protect_kernel_tunables_table, ELEMENTSOF(protect_kernel_tunables_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_kernel_tunables_table), typeof(&*(protect_kernel_tunables_table
))), sizeof(protect_kernel_tunables_table)/sizeof((protect_kernel_tunables_table
)[0]), ((void)0))), ns_info->ignore_protect_paths);
1249 if (r < 0)
1250 goto finish;
1251 }
1252
1253 if (ns_info->protect_kernel_modules) {
1254 r = append_static_mounts(&m, protect_kernel_modules_table, ELEMENTSOF(protect_kernel_modules_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_kernel_modules_table), typeof(&*(protect_kernel_modules_table
))), sizeof(protect_kernel_modules_table)/sizeof((protect_kernel_modules_table
)[0]), ((void)0))), ns_info->ignore_protect_paths);
1255 if (r < 0)
1256 goto finish;
1257 }
1258
1259 if (ns_info->protect_control_groups) {
1260 *(m++) = (MountEntry) {
1261 .path_const = "/sys/fs/cgroup",
1262 .mode = READONLY,
1263 };
1264 }
1265
1266 r = append_protect_home(&m, protect_home, ns_info->ignore_protect_paths);
1267 if (r < 0)
1268 goto finish;
1269
1270 r = append_protect_system(&m, protect_system, false0);
1271 if (r < 0)
1272 goto finish;
1273
1274 if (namespace_info_mount_apivfs(root, ns_info)) {
1275 r = append_static_mounts(&m, apivfs_table, ELEMENTSOF(apivfs_table)__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(apivfs_table), typeof(&*(apivfs_table))), sizeof(
apivfs_table)/sizeof((apivfs_table)[0]), ((void)0))), ns_info->ignore_protect_paths);
1276 if (r < 0)
1277 goto finish;
1278 }
1279
1280 assert(mounts + n_mounts == m)do { if ((__builtin_expect(!!(!(mounts + n_mounts == m)),0)))
log_assert_failed_realm(LOG_REALM_SYSTEMD, ("mounts + n_mounts == m"
), "../src/core/namespace.c", 1280, __PRETTY_FUNCTION__); } while
(0);
1281
1282 /* Prepend the root directory where that's necessary */
1283 r = prefix_where_needed(mounts, n_mounts, root);
1284 if (r < 0)
1285 goto finish;
1286
1287 normalize_mounts(root_directory, mounts, &n_mounts);
1288 }
1289
1290 if (unshare(CLONE_NEWNS0x00020000) < 0) {
1291 r = -errno(*__errno_location ());
1292 goto finish;
1293 }
1294
1295 if (make_slave) {
1296 /* Remount / as SLAVE so that nothing now mounted in the namespace
1297 shows up in the parent */
1298 if (mount(NULL((void*)0), "/", NULL((void*)0), MS_SLAVE(1<<19)|MS_REC16384, NULL((void*)0)) < 0) {
1299 r = -errno(*__errno_location ());
1300 goto finish;
1301 }
1302 }
1303
1304 if (root_image) {
1305 /* A root image is specified, mount it to the right place */
1306 r = dissected_image_mount(dissected_image, root, UID_INVALID((uid_t) -1), dissect_image_flags);
1307 if (r < 0)
1308 goto finish;
1309
1310 if (decrypted_image) {
1311 r = decrypted_image_relinquish(decrypted_image);
1312 if (r < 0)
1313 goto finish;
1314 }
1315
1316 loop_device_relinquish(loop_device);
1317
1318 } else if (root_directory) {
1319
1320 /* A root directory is specified. Turn its directory into bind mount, if it isn't one yet. */
1321 r = path_is_mount_point(root, NULL((void*)0), AT_SYMLINK_FOLLOW0x400);
1322 if (r < 0)
1323 goto finish;
1324 if (r == 0) {
1325 if (mount(root, root, NULL((void*)0), MS_BIND4096|MS_REC16384, NULL((void*)0)) < 0) {
1326 r = -errno(*__errno_location ());
1327 goto finish;
1328 }
1329 }
1330
1331 } else if (root) {
1332
1333 /* Let's mount the main root directory to the root directory to use */
1334 if (mount("/", root, NULL((void*)0), MS_BIND4096|MS_REC16384, NULL((void*)0)) < 0) {
1335 r = -errno(*__errno_location ());
1336 goto finish;
1337 }
1338 }
1339
1340 /* Try to set up the new root directory before mounting anything else there. */
1341 if (root_image || root_directory)
1342 (void) base_filesystem_create(root, UID_INVALID((uid_t) -1), GID_INVALID((gid_t) -1));
1343
1344 if (n_mounts > 0) {
1345 _cleanup_fclose___attribute__((cleanup(fclosep))) FILE *proc_self_mountinfo = NULL((void*)0);
1346 char **blacklist;
1347 size_t j;
1348
1349 /* Open /proc/self/mountinfo now as it may become unavailable if we mount anything on top of /proc.
1350 * For example, this is the case with the option: 'InaccessiblePaths=/proc' */
1351 proc_self_mountinfo = fopen("/proc/self/mountinfo", "re");
1352 if (!proc_self_mountinfo) {
1353 r = -errno(*__errno_location ());
1354 goto finish;
1355 }
1356
1357 /* First round, establish all mounts we need */
1358 for (;;) {
1359 bool_Bool again = false0;
1360
1361 for (m = mounts; m < mounts + n_mounts; ++m) {
1362
1363 if (m->applied)
1364 continue;
1365
1366 r = follow_symlink(root, m);
1367 if (r < 0)
1368 goto finish;
1369 if (r == 0) {
1370 /* We hit a symlinked mount point. The entry got rewritten and might point to a
1371 * very different place now. Let's normalize the changed list, and start from
1372 * the beginning. After all to mount the entry at the new location we might
1373 * need some other mounts first */
1374 again = true1;
1375 break;
1376 }
1377
1378 r = apply_mount(root, m);
1379 if (r < 0)
1380 goto finish;
1381
1382 m->applied = true1;
1383 }
1384
1385 if (!again)
1386 break;
1387
1388 normalize_mounts(root_directory, mounts, &n_mounts);
1389 }
1390
1391 /* Create a blacklist we can pass to bind_mount_recursive() */
1392 blacklist = newa(char*, n_mounts+1)({ do { if ((__builtin_expect(!!(!(!size_multiply_overflow(sizeof
(char*), n_mounts+1))),0))) log_assert_failed_realm(LOG_REALM_SYSTEMD
, ("!size_multiply_overflow(sizeof(char*), n_mounts+1)"), "../src/core/namespace.c"
, 1392, __PRETTY_FUNCTION__); } while (0); (char**) __builtin_alloca
(sizeof(char*)*(n_mounts+1)); });
1393 for (j = 0; j < n_mounts; j++)
1394 blacklist[j] = (char*) mount_entry_path(mounts+j);
1395 blacklist[j] = NULL((void*)0);
1396
1397 /* Second round, flip the ro bits if necessary. */
1398 for (m = mounts; m < mounts + n_mounts; ++m) {
1399 r = make_read_only(m, blacklist, proc_self_mountinfo);
1400 if (r < 0)
1401 goto finish;
1402 }
1403 }
1404
1405 if (root) {
1406 /* MS_MOVE does not work on MS_SHARED so the remount MS_SHARED will be done later */
1407 r = mount_move_root(root);
1408 if (r < 0)
1409 goto finish;
1410 }
1411
1412 /* Remount / as the desired mode. Note that this will not
1413 * reestablish propagation from our side to the host, since
1414 * what's disconnected is disconnected. */
1415 if (mount(NULL((void*)0), "/", NULL((void*)0), mount_flags | MS_REC16384, NULL((void*)0)) < 0) {
1416 r = -errno(*__errno_location ());
1417 goto finish;
1418 }
1419
1420 r = 0;
1421
1422finish:
1423 for (m = mounts; m < mounts + n_mounts; m++)
1424 mount_entry_done(m);
1425
1426 return r;
1427}
1428
1429void bind_mount_free_many(BindMount *b, size_t n) {
1430 size_t i;
1431
1432 assert(b || n == 0)do { if ((__builtin_expect(!!(!(b || n == 0)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("b || n == 0"), "../src/core/namespace.c"
, 1432, __PRETTY_FUNCTION__); } while (0);
1433
1434 for (i = 0; i < n; i++) {
1435 free(b[i].source);
1436 free(b[i].destination);
1437 }
1438
1439 free(b);
1440}
1441
1442int bind_mount_add(BindMount **b, size_t *n, const BindMount *item) {
1443 _cleanup_free___attribute__((cleanup(freep))) char *s = NULL((void*)0), *d = NULL((void*)0);
1444 BindMount *c;
1445
1446 assert(b)do { if ((__builtin_expect(!!(!(b)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("b"), "../src/core/namespace.c", 1446, __PRETTY_FUNCTION__
); } while (0);
1
Assuming 'b' is non-null
→
2
←
Taking false branch
→
3
←
Loop condition is false. Exiting loop
→
1447 assert(n)do { if ((__builtin_expect(!!(!(n)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("n"), "../src/core/namespace.c", 1447, __PRETTY_FUNCTION__
); } while (0);
4
←
Assuming 'n' is non-null
→
5
←
Taking false branch
→
6
←
Loop condition is false. Exiting loop
→
1448 assert(item)do { if ((__builtin_expect(!!(!(item)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("item"), "../src/core/namespace.c", 1448
, __PRETTY_FUNCTION__); } while (0);
7
←
Assuming 'item' is non-null
→
8
←
Taking false branch
→
9
←
Loop condition is false. Exiting loop
→
1449
1450 s = strdup(item->source);
10
←
Memory is allocated
→
1451 if (!s)
11
←
Assuming 's' is non-null
→
12
←
Taking false branch
→
1452 return -ENOMEM12;
1453
1454 d = strdup(item->destination);
1455 if (!d)
13
←
Assuming 'd' is null
→
14
←
Taking true branch
→
1456 return -ENOMEM12;
15
←
Potential leak of memory pointed to by 's'
1457
1458 c = reallocarray(*b, *n + 1, sizeof(BindMount));
1459 if (!c)
1460 return -ENOMEM12;
1461
1462 *b = c;
1463
1464 c[(*n) ++] = (BindMount) {
1465 .source = TAKE_PTR(s)({ typeof(s) _ptr_ = (s); (s) = ((void*)0); _ptr_; }),
1466 .destination = TAKE_PTR(d)({ typeof(d) _ptr_ = (d); (d) = ((void*)0); _ptr_; }),
1467 .read_only = item->read_only,
1468 .recursive = item->recursive,
1469 .ignore_enoent = item->ignore_enoent,
1470 };
1471
1472 return 0;
1473}
1474
1475void temporary_filesystem_free_many(TemporaryFileSystem *t, size_t n) {
1476 size_t i;
1477
1478 assert(t || n == 0)do { if ((__builtin_expect(!!(!(t || n == 0)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("t || n == 0"), "../src/core/namespace.c"
, 1478, __PRETTY_FUNCTION__); } while (0);
1479
1480 for (i = 0; i < n; i++) {
1481 free(t[i].path);
1482 free(t[i].options);
1483 }
1484
1485 free(t);
1486}
1487
1488int temporary_filesystem_add(
1489 TemporaryFileSystem **t,
1490 size_t *n,
1491 const char *path,
1492 const char *options) {
1493
1494 _cleanup_free___attribute__((cleanup(freep))) char *p = NULL((void*)0), *o = NULL((void*)0);
1495 TemporaryFileSystem *c;
1496
1497 assert(t)do { if ((__builtin_expect(!!(!(t)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("t"), "../src/core/namespace.c", 1497, __PRETTY_FUNCTION__
); } while (0);
1498 assert(n)do { if ((__builtin_expect(!!(!(n)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("n"), "../src/core/namespace.c", 1498, __PRETTY_FUNCTION__
); } while (0);
1499 assert(path)do { if ((__builtin_expect(!!(!(path)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("path"), "../src/core/namespace.c", 1499
, __PRETTY_FUNCTION__); } while (0);
1500
1501 p = strdup(path);
1502 if (!p)
1503 return -ENOMEM12;
1504
1505 if (!isempty(options)) {
1506 o = strdup(options);
1507 if (!o)
1508 return -ENOMEM12;
1509 }
1510
1511 c = reallocarray(*t, *n + 1, sizeof(TemporaryFileSystem));
1512 if (!c)
1513 return -ENOMEM12;
1514
1515 *t = c;
1516
1517 c[(*n) ++] = (TemporaryFileSystem) {
1518 .path = TAKE_PTR(p)({ typeof(p) _ptr_ = (p); (p) = ((void*)0); _ptr_; }),
1519 .options = TAKE_PTR(o)({ typeof(o) _ptr_ = (o); (o) = ((void*)0); _ptr_; }),
1520 };
1521
1522 return 0;
1523}
1524
1525static int setup_one_tmp_dir(const char *id, const char *prefix, char **path) {
1526 _cleanup_free___attribute__((cleanup(freep))) char *x = NULL((void*)0);
1527 char bid[SD_ID128_STRING_MAX33];
1528 sd_id128_t boot_id;
1529 int r;
1530
1531 assert(id)do { if ((__builtin_expect(!!(!(id)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("id"), "../src/core/namespace.c", 1531, __PRETTY_FUNCTION__
); } while (0);
1532 assert(prefix)do { if ((__builtin_expect(!!(!(prefix)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("prefix"), "../src/core/namespace.c", 1532
, __PRETTY_FUNCTION__); } while (0);
1533 assert(path)do { if ((__builtin_expect(!!(!(path)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("path"), "../src/core/namespace.c", 1533
, __PRETTY_FUNCTION__); } while (0);
1534
1535 /* We include the boot id in the directory so that after a
1536 * reboot we can easily identify obsolete directories. */
1537
1538 r = sd_id128_get_boot(&boot_id);
1539 if (r < 0)
1540 return r;
1541
1542 x = strjoin(prefix, "/systemd-private-", sd_id128_to_string(boot_id, bid), "-", id, "-XXXXXX")strjoin_real((prefix), "/systemd-private-", sd_id128_to_string
(boot_id, bid), "-", id, "-XXXXXX", ((void*)0));
1543 if (!x)
1544 return -ENOMEM12;
1545
1546 RUN_WITH_UMASK(0077)for (__attribute__((cleanup(_reset_umask_))) struct _umask_struct_
_saved_umask_ = { umask(0077), 0 }; !_saved_umask_.quit ; _saved_umask_
.quit = 1)
1547 if (!mkdtemp(x))
1548 return -errno(*__errno_location ());
1549
1550 RUN_WITH_UMASK(0000)for (__attribute__((cleanup(_reset_umask_))) struct _umask_struct_
_saved_umask_ = { umask(0000), 0 }; !_saved_umask_.quit ; _saved_umask_
.quit = 1) {
1551 char *y;
1552
1553 y = strjoina(x, "/tmp")({ const char *_appendees_[] = { x, "/tmp" }; char *_d_, *_p_
; size_t _len_ = 0; size_t _i_; for (_i_ = 0; _i_ < __extension__
(__builtin_choose_expr( !__builtin_types_compatible_p(typeof
(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
1554
1555 if (mkdir(y, 0777 | S_ISVTX01000) < 0)
1556 return -errno(*__errno_location ());
1557 }
1558
1559 *path = TAKE_PTR(x)({ typeof(x) _ptr_ = (x); (x) = ((void*)0); _ptr_; });
1560
1561 return 0;
1562}
1563
1564int setup_tmp_dirs(const char *id, char **tmp_dir, char **var_tmp_dir) {
1565 char *a, *b;
1566 int r;
1567
1568 assert(id)do { if ((__builtin_expect(!!(!(id)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("id"), "../src/core/namespace.c", 1568, __PRETTY_FUNCTION__
); } while (0);
1569 assert(tmp_dir)do { if ((__builtin_expect(!!(!(tmp_dir)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("tmp_dir"), "../src/core/namespace.c", 1569
, __PRETTY_FUNCTION__); } while (0);
1570 assert(var_tmp_dir)do { if ((__builtin_expect(!!(!(var_tmp_dir)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("var_tmp_dir"), "../src/core/namespace.c"
, 1570, __PRETTY_FUNCTION__); } while (0);
1571
1572 r = setup_one_tmp_dir(id, "/tmp", &a);
1573 if (r < 0)
1574 return r;
1575
1576 r = setup_one_tmp_dir(id, "/var/tmp", &b);
1577 if (r < 0) {
1578 char *t;
1579
1580 t = strjoina(a, "/tmp")({ const char *_appendees_[] = { a, "/tmp" }; char *_d_, *_p_
; size_t _len_ = 0; size_t _i_; for (_i_ = 0; _i_ < __extension__
(__builtin_choose_expr( !__builtin_types_compatible_p(typeof
(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
1581 rmdir(t);
1582 rmdir(a);
1583
1584 free(a);
1585 return r;
1586 }
1587
1588 *tmp_dir = a;
1589 *var_tmp_dir = b;
1590
1591 return 0;
1592}
1593
1594int setup_netns(int netns_storage_socket[2]) {
1595 _cleanup_close___attribute__((cleanup(closep))) int netns = -1;
1596 int r, q;
1597
1598 assert(netns_storage_socket)do { if ((__builtin_expect(!!(!(netns_storage_socket)),0))) log_assert_failed_realm
(LOG_REALM_SYSTEMD, ("netns_storage_socket"), "../src/core/namespace.c"
, 1598, __PRETTY_FUNCTION__); } while (0);
1599 assert(netns_storage_socket[0] >= 0)do { if ((__builtin_expect(!!(!(netns_storage_socket[0] >=
0)),0))) log_assert_failed_realm(LOG_REALM_SYSTEMD, ("netns_storage_socket[0] >= 0"
), "../src/core/namespace.c", 1599, __PRETTY_FUNCTION__); } while
(0);
1600 assert(netns_storage_socket[1] >= 0)do { if ((__builtin_expect(!!(!(netns_storage_socket[1] >=
0)),0))) log_assert_failed_realm(LOG_REALM_SYSTEMD, ("netns_storage_socket[1] >= 0"
), "../src/core/namespace.c", 1600, __PRETTY_FUNCTION__); } while
(0);
1601
1602 /* We use the passed socketpair as a storage buffer for our
1603 * namespace reference fd. Whatever process runs this first
1604 * shall create a new namespace, all others should just join
1605 * it. To serialize that we use a file lock on the socket
1606 * pair.
1607 *
1608 * It's a bit crazy, but hey, works great! */
1609
1610 if (lockf(netns_storage_socket[0], F_LOCK1, 0) < 0)
1611 return -errno(*__errno_location ());
1612
1613 netns = receive_one_fd(netns_storage_socket[0], MSG_DONTWAITMSG_DONTWAIT);
1614 if (netns == -EAGAIN11) {
1615 /* Nothing stored yet, so let's create a new namespace */
1616
1617 if (unshare(CLONE_NEWNET0x40000000) < 0) {
1618 r = -errno(*__errno_location ());
1619 goto fail;
1620 }
1621
1622 loopback_setup();
1623
1624 netns = open("/proc/self/ns/net", O_RDONLY00|O_CLOEXEC02000000|O_NOCTTY0400);
1625 if (netns < 0) {
1626 r = -errno(*__errno_location ());
1627 goto fail;
1628 }
1629
1630 r = 1;
1631
1632 } else if (netns < 0) {
1633 r = netns;
1634 goto fail;
1635
1636 } else {
1637 /* Yay, found something, so let's join the namespace */
1638 if (setns(netns, CLONE_NEWNET0x40000000) < 0) {
1639 r = -errno(*__errno_location ());
1640 goto fail;
1641 }
1642
1643 r = 0;
1644 }
1645
1646 q = send_one_fd(netns_storage_socket[1], netns, MSG_DONTWAIT)send_one_fd_iov_sa(netns_storage_socket[1], netns, ((void*)0)
, 0, ((void*)0), 0, MSG_DONTWAIT);
1647 if (q < 0) {
1648 r = q;
1649 goto fail;
1650 }
1651
1652fail:
1653 (void) lockf(netns_storage_socket[0], F_ULOCK0, 0);
1654 return r;
1655}
1656
1657bool_Bool ns_type_supported(NamespaceType type) {
1658 const char *t, *ns_proc;
1659
1660 t = namespace_type_to_string(type);
1661 if (!t) /* Don't know how to translate this? Then it's not supported */
1662 return false0;
1663
1664 ns_proc = strjoina("/proc/self/ns/", t)({ const char *_appendees_[] = { "/proc/self/ns/", t }; char *
_d_, *_p_; size_t _len_ = 0; size_t _i_; for (_i_ = 0; _i_ <
__extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(_appendees_), typeof(&*(_appendees_))), sizeof(_appendees_
)/sizeof((_appendees_)[0]), ((void)0))) && _appendees_
[_i_]; _i_++) _len_ += strlen(_appendees_[_i_]); _p_ = _d_ = __builtin_alloca
(_len_ + 1); for (_i_ = 0; _i_ < __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(_appendees_), typeof(&
*(_appendees_))), sizeof(_appendees_)/sizeof((_appendees_)[0]
), ((void)0))) && _appendees_[_i_]; _i_++) _p_ = stpcpy
(_p_, _appendees_[_i_]); *_p_ = 0; _d_; });
1665 return access(ns_proc, F_OK0) == 0;
1666}
1667
1668static const char *const protect_home_table[_PROTECT_HOME_MAX] = {
1669 [PROTECT_HOME_NO] = "no",
1670 [PROTECT_HOME_YES] = "yes",
1671 [PROTECT_HOME_READ_ONLY] = "read-only",
1672 [PROTECT_HOME_TMPFS] = "tmpfs",
1673};
1674
1675DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(protect_home, ProtectHome, PROTECT_HOME_YES)const char *protect_home_to_string(ProtectHome i) { if (i <
0 || i >= (ProtectHome) __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(protect_home_table), typeof
(&*(protect_home_table))), sizeof(protect_home_table)/sizeof
((protect_home_table)[0]), ((void)0)))) return ((void*)0); return
protect_home_table[i]; } ProtectHome protect_home_from_string
(const char *s) { int b; if (!s) return -1; b = parse_boolean
(s); if (b == 0) return (ProtectHome) 0; else if (b > 0) return
PROTECT_HOME_YES; return (ProtectHome) string_table_lookup(protect_home_table
, __extension__ (__builtin_choose_expr( !__builtin_types_compatible_p
(typeof(protect_home_table), typeof(&*(protect_home_table
))), sizeof(protect_home_table)/sizeof((protect_home_table)[0
]), ((void)0))), s); };
1676
1677static const char *const protect_system_table[_PROTECT_SYSTEM_MAX] = {
1678 [PROTECT_SYSTEM_NO] = "no",
1679 [PROTECT_SYSTEM_YES] = "yes",
1680 [PROTECT_SYSTEM_FULL] = "full",
1681 [PROTECT_SYSTEM_STRICT] = "strict",
1682};
1683
1684DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(protect_system, ProtectSystem, PROTECT_SYSTEM_YES)const char *protect_system_to_string(ProtectSystem i) { if (i
< 0 || i >= (ProtectSystem) __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(protect_system_table),
typeof(&*(protect_system_table))), sizeof(protect_system_table
)/sizeof((protect_system_table)[0]), ((void)0)))) return ((void
*)0); return protect_system_table[i]; } ProtectSystem protect_system_from_string
(const char *s) { int b; if (!s) return -1; b = parse_boolean
(s); if (b == 0) return (ProtectSystem) 0; else if (b > 0)
return PROTECT_SYSTEM_YES; return (ProtectSystem) string_table_lookup
(protect_system_table, __extension__ (__builtin_choose_expr( !
__builtin_types_compatible_p(typeof(protect_system_table), typeof
(&*(protect_system_table))), sizeof(protect_system_table)
/sizeof((protect_system_table)[0]), ((void)0))), s); };
1685
1686static const char* const namespace_type_table[] = {
1687 [NAMESPACE_MOUNT] = "mnt",
1688 [NAMESPACE_CGROUP] = "cgroup",
1689 [NAMESPACE_UTS] = "uts",
1690 [NAMESPACE_IPC] = "ipc",
1691 [NAMESPACE_USER] = "user",
1692 [NAMESPACE_PID] = "pid",
1693 [NAMESPACE_NET] = "net",
1694};
1695
1696DEFINE_STRING_TABLE_LOOKUP(namespace_type, NamespaceType)const char *namespace_type_to_string(NamespaceType i) { if (i
< 0 || i >= (NamespaceType) __extension__ (__builtin_choose_expr
( !__builtin_types_compatible_p(typeof(namespace_type_table),
typeof(&*(namespace_type_table))), sizeof(namespace_type_table
)/sizeof((namespace_type_table)[0]), ((void)0)))) return ((void
*)0); return namespace_type_table[i]; } NamespaceType namespace_type_from_string
(const char *s) { return (NamespaceType) string_table_lookup(
namespace_type_table, __extension__ (__builtin_choose_expr( !
__builtin_types_compatible_p(typeof(namespace_type_table), typeof
(&*(namespace_type_table))), sizeof(namespace_type_table)
/sizeof((namespace_type_table)[0]), ((void)0))), s); };