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>
This commit is contained in:
Aitor Esteve Alvarado 2019-03-07 10:14:48 +01:00 committed by Denys Vlasenko
parent 894f0a3235
commit 7b6d4f50c9

View File

@ -537,6 +537,15 @@ int start_stop_daemon_main(int argc UNUSED_PARAM, char **argv)
/* 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 @@ int start_stop_daemon_main(int argc UNUSED_PARAM, char **argv)
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":