From 530cc24c83dd5d2d347acb40d64c3ae06a43a293 Mon Sep 17 00:00:00 2001 From: Arthur de Jong Date: Wed, 15 Apr 2015 23:55:14 +0200 Subject: Avoid signal race condition on start-up This only restores the signal mask after signal handlers are in place and the daemon has completely daemonised to avoid a race condition in the start-up phase of nslcd where a signal could be sent to nslcd causing it to quit or fail to write information to the parent process. --- nslcd/daemonize.c | 2 +- nslcd/nslcd.c | 5 +++-- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/nslcd/daemonize.c b/nslcd/daemonize.c index 60f2d91..d11d358 100644 --- a/nslcd/daemonize.c +++ b/nslcd/daemonize.c @@ -89,7 +89,7 @@ static int read_response(int fd, char *buffer, size_t bufsz) return r; } -/* ihe process calling daemonize_daemon() will end up here on success */ +/* The parent process calling daemonize_daemon() will end up here on success */ static int wait_for_response(int fd) { int i, l, rc; diff --git a/nslcd/nslcd.c b/nslcd/nslcd.c index f765b9c..469793a 100644 --- a/nslcd/nslcd.c +++ b/nslcd/nslcd.c @@ -838,8 +838,7 @@ int main(int argc, char *argv[]) exit(EXIT_FAILURE); } } - pthread_sigmask(SIG_SETMASK, &oldmask, NULL); - /* install signalhandlers for some signals */ + /* install signal handlers for some signals */ install_sighandler(SIGHUP, sig_handler); install_sighandler(SIGINT, sig_handler); install_sighandler(SIGQUIT, sig_handler); @@ -850,6 +849,8 @@ int main(int argc, char *argv[]) install_sighandler(SIGUSR2, SIG_IGN); /* signal the starting process to exit because we can provide services now */ daemonize_ready(EXIT_SUCCESS, NULL); + /* enable receiving of signals */ + pthread_sigmask(SIG_SETMASK, &oldmask, NULL); /* wait until we received a signal */ while ((nslcd_receivedsignal == 0) || (nslcd_receivedsignal == SIGUSR1)) { -- cgit v1.2.3