]>
git.ipfire.org Git - thirdparty/systemd.git/blob - src/shared/clean-ipc.c
2 This file is part of systemd.
4 Copyright 2014 Lennart Poettering
6 systemd is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
11 systemd is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License
17 along with systemd; If not, see <http://www.gnu.org/licenses/>.
35 #include "clean-ipc.h"
36 #include "dirent-util.h"
39 #include "format-util.h"
42 #include "string-util.h"
44 #include "user-util.h"
46 static bool match_uid_gid(uid_t subject_uid
, gid_t subject_gid
, uid_t delete_uid
, gid_t delete_gid
) {
48 if (uid_is_valid(delete_uid
) && subject_uid
== delete_uid
)
51 if (gid_is_valid(delete_gid
) && subject_gid
== delete_gid
)
57 static int clean_sysvipc_shm(uid_t delete_uid
, gid_t delete_gid
, bool rm
) {
58 _cleanup_fclose_
FILE *f
= NULL
;
63 f
= fopen("/proc/sysvipc/shm", "re");
68 return log_warning_errno(errno
, "Failed to open /proc/sysvipc/shm: %m");
71 FOREACH_LINE(line
, f
, goto fail
) {
85 if (sscanf(line
, "%*i %i %*o %*u " PID_FMT
" " PID_FMT
" %u " UID_FMT
" " GID_FMT
" " UID_FMT
" " GID_FMT
,
86 &shmid
, &cpid
, &lpid
, &n_attached
, &uid
, &gid
, &cuid
, &cgid
) != 8)
92 if (!match_uid_gid(uid
, gid
, delete_uid
, delete_gid
))
98 if (shmctl(shmid
, IPC_RMID
, NULL
) < 0) {
100 /* Ignore entries that are already deleted */
101 if (IN_SET(errno
, EIDRM
, EINVAL
))
104 ret
= log_warning_errno(errno
,
105 "Failed to remove SysV shared memory segment %i: %m",
108 log_debug("Removed SysV shared memory segment %i.", shmid
);
117 return log_warning_errno(errno
, "Failed to read /proc/sysvipc/shm: %m");
120 static int clean_sysvipc_sem(uid_t delete_uid
, gid_t delete_gid
, bool rm
) {
121 _cleanup_fclose_
FILE *f
= NULL
;
126 f
= fopen("/proc/sysvipc/sem", "re");
131 return log_warning_errno(errno
, "Failed to open /proc/sysvipc/sem: %m");
134 FOREACH_LINE(line
, f
, goto fail
) {
146 if (sscanf(line
, "%*i %i %*o %*u " UID_FMT
" " GID_FMT
" " UID_FMT
" " GID_FMT
,
147 &semid
, &uid
, &gid
, &cuid
, &cgid
) != 5)
150 if (!match_uid_gid(uid
, gid
, delete_uid
, delete_gid
))
156 if (semctl(semid
, 0, IPC_RMID
) < 0) {
158 /* Ignore entries that are already deleted */
159 if (IN_SET(errno
, EIDRM
, EINVAL
))
162 ret
= log_warning_errno(errno
,
163 "Failed to remove SysV semaphores object %i: %m",
166 log_debug("Removed SysV semaphore %i.", semid
);
175 return log_warning_errno(errno
, "Failed to read /proc/sysvipc/sem: %m");
178 static int clean_sysvipc_msg(uid_t delete_uid
, gid_t delete_gid
, bool rm
) {
179 _cleanup_fclose_
FILE *f
= NULL
;
184 f
= fopen("/proc/sysvipc/msg", "re");
189 return log_warning_errno(errno
, "Failed to open /proc/sysvipc/msg: %m");
192 FOREACH_LINE(line
, f
, goto fail
) {
205 if (sscanf(line
, "%*i %i %*o %*u %*u " PID_FMT
" " PID_FMT
" " UID_FMT
" " GID_FMT
" " UID_FMT
" " GID_FMT
,
206 &msgid
, &cpid
, &lpid
, &uid
, &gid
, &cuid
, &cgid
) != 7)
209 if (!match_uid_gid(uid
, gid
, delete_uid
, delete_gid
))
215 if (msgctl(msgid
, IPC_RMID
, NULL
) < 0) {
217 /* Ignore entries that are already deleted */
218 if (IN_SET(errno
, EIDRM
, EINVAL
))
221 ret
= log_warning_errno(errno
,
222 "Failed to remove SysV message queue %i: %m",
225 log_debug("Removed SysV message queue %i.", msgid
);
234 return log_warning_errno(errno
, "Failed to read /proc/sysvipc/msg: %m");
237 static int clean_posix_shm_internal(DIR *dir
, uid_t uid
, gid_t gid
, bool rm
) {
243 FOREACH_DIRENT_ALL(de
, dir
, goto fail
) {
246 if (dot_or_dot_dot(de
->d_name
))
249 if (fstatat(dirfd(dir
), de
->d_name
, &st
, AT_SYMLINK_NOFOLLOW
) < 0) {
253 ret
= log_warning_errno(errno
, "Failed to stat() POSIX shared memory segment %s: %m", de
->d_name
);
257 if (S_ISDIR(st
.st_mode
)) {
258 _cleanup_closedir_
DIR *kid
;
260 kid
= xopendirat(dirfd(dir
), de
->d_name
, O_NOFOLLOW
|O_NOATIME
);
263 ret
= log_warning_errno(errno
, "Failed to enter shared memory directory %s: %m", de
->d_name
);
265 r
= clean_posix_shm_internal(kid
, uid
, gid
, rm
);
270 if (!match_uid_gid(st
.st_uid
, st
.st_gid
, uid
, gid
))
276 if (unlinkat(dirfd(dir
), de
->d_name
, AT_REMOVEDIR
) < 0) {
281 ret
= log_warning_errno(errno
, "Failed to remove POSIX shared memory directory %s: %m", de
->d_name
);
283 log_debug("Removed POSIX shared memory directory %s", de
->d_name
);
289 if (!match_uid_gid(st
.st_uid
, st
.st_gid
, uid
, gid
))
295 if (unlinkat(dirfd(dir
), de
->d_name
, 0) < 0) {
300 ret
= log_warning_errno(errno
, "Failed to remove POSIX shared memory segment %s: %m", de
->d_name
);
302 log_debug("Removed POSIX shared memory segment %s", de
->d_name
);
312 return log_warning_errno(errno
, "Failed to read /dev/shm: %m");
315 static int clean_posix_shm(uid_t uid
, gid_t gid
, bool rm
) {
316 _cleanup_closedir_
DIR *dir
= NULL
;
318 dir
= opendir("/dev/shm");
323 return log_warning_errno(errno
, "Failed to open /dev/shm: %m");
326 return clean_posix_shm_internal(dir
, uid
, gid
, rm
);
329 static int clean_posix_mq(uid_t uid
, gid_t gid
, bool rm
) {
330 _cleanup_closedir_
DIR *dir
= NULL
;
334 dir
= opendir("/dev/mqueue");
339 return log_warning_errno(errno
, "Failed to open /dev/mqueue: %m");
342 FOREACH_DIRENT_ALL(de
, dir
, goto fail
) {
344 char fn
[1+strlen(de
->d_name
)+1];
346 if (dot_or_dot_dot(de
->d_name
))
349 if (fstatat(dirfd(dir
), de
->d_name
, &st
, AT_SYMLINK_NOFOLLOW
) < 0) {
353 ret
= log_warning_errno(errno
,
354 "Failed to stat() MQ segment %s: %m",
359 if (!match_uid_gid(st
.st_uid
, st
.st_gid
, uid
, gid
))
366 strcpy(fn
+1, de
->d_name
);
368 if (mq_unlink(fn
) < 0) {
372 ret
= log_warning_errno(errno
,
373 "Failed to unlink POSIX message queue %s: %m",
376 log_debug("Removed POSIX message queue %s", fn
);
385 return log_warning_errno(errno
, "Failed to read /dev/mqueue: %m");
388 int clean_ipc_internal(uid_t uid
, gid_t gid
, bool rm
) {
391 /* If 'rm' is true, clean all IPC objects owned by either the specified UID or the specified GID. Return the
392 * last error encountered or == 0 if no matching IPC objects have been found or > 0 if matching IPC objects
393 * have been found and have been removed.
395 * If 'rm' is false, just search for IPC objects owned by either the specified UID or the specified GID. In
396 * this case we return < 0 on error, > 0 if we found a matching object, == 0 if we didn't.
398 * As special rule: if UID/GID is specified as root we'll silently not clean up things, and always claim that
399 * there are IPC objects for it. */
414 /* Anything to do? */
415 if (!uid_is_valid(uid
) && !gid_is_valid(gid
))
418 r
= clean_sysvipc_shm(uid
, gid
, rm
);
426 r
= clean_sysvipc_sem(uid
, gid
, rm
);
434 r
= clean_sysvipc_msg(uid
, gid
, rm
);
442 r
= clean_posix_shm(uid
, gid
, rm
);
450 r
= clean_posix_mq(uid
, gid
, rm
);
461 int clean_ipc_by_uid(uid_t uid
) {
462 return clean_ipc_internal(uid
, GID_INVALID
, true);
465 int clean_ipc_by_gid(gid_t gid
) {
466 return clean_ipc_internal(UID_INVALID
, gid
, true);