]>
git.ipfire.org Git - thirdparty/systemd.git/blob - src/core/killall.c
2 This file is part of systemd.
4 Copyright 2010 ProFUSION embedded systems
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/>.
25 #include "alloc-util.h"
27 #include "dirent-util.h"
29 #include "format-util.h"
31 #include "parse-util.h"
32 #include "process-util.h"
34 #include "string-util.h"
35 #include "terminal-util.h"
38 static bool ignore_proc(pid_t pid
, bool warn_rootfs
) {
39 _cleanup_fclose_
FILE *f
= NULL
;
46 /* We are PID 1, let's not commit suicide */
50 r
= get_process_uid(pid
, &uid
);
52 return true; /* not really, but better safe than sorry */
54 /* Non-root processes otherwise are always subject to be killed */
58 p
= procfs_file_alloca(pid
, "cmdline");
61 return true; /* not really, but has the desired effect */
63 count
= fread(&c
, 1, 1, f
);
65 /* Kernel threads have an empty cmdline */
69 /* Processes with argv[0][0] = '@' we ignore from the killing spree.
71 * http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons */
76 pid_from_same_root_fs(pid
) == 0) {
78 _cleanup_free_
char *comm
= NULL
;
80 get_process_comm(pid
, &comm
);
82 log_notice("Process " PID_FMT
" (%s) has been marked to be excluded from killing. It is "
83 "running from the root file system, and thus likely to block re-mounting of the "
84 "root file system to read-only. Please consider moving it into an initrd file "
85 "system instead.", pid
, strna(comm
));
91 static void wait_for_children(Set
*pids
, sigset_t
*mask
) {
96 if (set_isempty(pids
))
99 until
= now(CLOCK_MONOTONIC
) + DEFAULT_TIMEOUT_USEC
;
107 /* First, let the kernel inform us about killed
108 * children. Most processes will probably be our
109 * children, but some are not (might be our
110 * grandchildren instead...). */
114 pid
= waitpid(-1, NULL
, WNOHANG
);
121 log_error_errno(errno
, "waitpid() failed: %m");
125 (void) set_remove(pids
, PID_TO_PTR(pid
));
128 /* Now explicitly check who might be remaining, who
129 * might not be our child. */
130 SET_FOREACH(p
, pids
, i
) {
132 /* We misuse getpgid as a check whether a
133 * process still exists. */
134 if (getpgid(PTR_TO_PID(p
)) >= 0)
143 if (set_isempty(pids
))
146 n
= now(CLOCK_MONOTONIC
);
150 timespec_store(&ts
, until
- n
);
151 k
= sigtimedwait(mask
, NULL
, &ts
);
154 if (k
< 0 && errno
!= EAGAIN
) {
155 log_error_errno(errno
, "sigtimedwait() failed: %m");
160 log_warning("sigtimedwait() returned unexpected signal.");
165 static int killall(int sig
, Set
*pids
, bool send_sighup
) {
166 _cleanup_closedir_
DIR *dir
= NULL
;
169 dir
= opendir("/proc");
173 FOREACH_DIRENT_ALL(d
, dir
, break) {
177 if (d
->d_type
!= DT_DIR
&&
178 d
->d_type
!= DT_UNKNOWN
)
181 if (parse_pid(d
->d_name
, &pid
) < 0)
184 if (ignore_proc(pid
, sig
== SIGKILL
&& !in_initrd()))
187 if (sig
== SIGKILL
) {
188 _cleanup_free_
char *s
= NULL
;
190 get_process_comm(pid
, &s
);
191 log_notice("Sending SIGKILL to PID "PID_FMT
" (%s).", pid
, strna(s
));
194 if (kill(pid
, sig
) >= 0) {
196 r
= set_put(pids
, PID_TO_PTR(pid
));
200 } else if (errno
!= ENOENT
)
201 log_warning_errno(errno
, "Could not kill %d: %m", pid
);
204 /* Optionally, also send a SIGHUP signal, but
205 only if the process has a controlling
206 tty. This is useful to allow handling of
207 shells which ignore SIGTERM but react to
208 SIGHUP. We do not send this to processes that
209 have no controlling TTY since we don't want to
210 trigger reloads of daemon processes. Also we
211 make sure to only send this after SIGTERM so
212 that SIGTERM is always first in the queue. */
215 if (get_ctty_devnr(pid
, NULL
) >= 0)
216 /* it's OK if the process is gone, just ignore the result */
217 (void) kill(pid
, SIGHUP
);
221 return set_size(pids
);
224 void broadcast_signal(int sig
, bool wait_for_exit
, bool send_sighup
) {
225 sigset_t mask
, oldmask
;
226 _cleanup_set_free_ Set
*pids
= NULL
;
229 pids
= set_new(NULL
);
231 assert_se(sigemptyset(&mask
) == 0);
232 assert_se(sigaddset(&mask
, SIGCHLD
) == 0);
233 assert_se(sigprocmask(SIG_BLOCK
, &mask
, &oldmask
) == 0);
235 if (kill(-1, SIGSTOP
) < 0 && errno
!= ESRCH
)
236 log_warning_errno(errno
, "kill(-1, SIGSTOP) failed: %m");
238 killall(sig
, pids
, send_sighup
);
240 if (kill(-1, SIGCONT
) < 0 && errno
!= ESRCH
)
241 log_warning_errno(errno
, "kill(-1, SIGCONT) failed: %m");
244 wait_for_children(pids
, &mask
);
246 assert_se(sigprocmask(SIG_SETMASK
, &oldmask
, NULL
) == 0);