start-stop-daemon: change priority before dropping privileges
Currently start-stop-daemon fails when using both the -c option (set uid)
and -N option (set niceness/priority) as it first drops privileges and then
tries to increase the priority. This patch changes the order of execution.
Signed-off-by: Aitor Esteve Alvarado <aesteve@singularaircraft.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/debianutils/start_stop_daemon.c b/debianutils/start_stop_daemon.c
index 72642ae..6fbf8b6 100644
--- a/debianutils/start_stop_daemon.c
+++ b/debianutils/start_stop_daemon.c
@@ -537,6 +537,15 @@
/* User wants _us_ to make the pidfile */
write_pidfile(pidfile);
}
+#if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
+ if (opt & OPT_NICELEVEL) {
+ /* Set process priority (must be before OPT_c) */
+ int prio = getpriority(PRIO_PROCESS, 0) + xatoi_range(opt_N, INT_MIN/2, INT_MAX/2);
+ if (setpriority(PRIO_PROCESS, 0, prio) < 0) {
+ bb_perror_msg_and_die("setpriority(%d)", prio);
+ }
+ }
+#endif
if (opt & OPT_c) {
struct bb_uidgid_t ugid;
parse_chown_usergroup_or_die(&ugid, chuid);
@@ -551,15 +560,6 @@
setgroups(1, &ugid.gid);
}
}
-#if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
- if (opt & OPT_NICELEVEL) {
- /* Set process priority */
- int prio = getpriority(PRIO_PROCESS, 0) + xatoi_range(opt_N, INT_MIN/2, INT_MAX/2);
- if (setpriority(PRIO_PROCESS, 0, prio) < 0) {
- bb_perror_msg_and_die("setpriority(%d)", prio);
- }
- }
-#endif
/* Try:
* strace -oLOG start-stop-daemon -S -x /bin/usleep -a qwerty 500000
* should exec "/bin/usleep", but argv[0] should be "qwerty":