From: Michał Kępień <michal@isc.org>
Date: Wed, 19 Jan 2022 13:30:17 +0000 (+0100)
Subject: rndc: prevent crashing after receiving a signal
X-Git-Tag: v9.18.0~7^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d1d721aae1ba9bef8752b2d55bdc95b603096447;p=thirdparty%2Fbind9.git

rndc: prevent crashing after receiving a signal

If isc_app_run() gets interrupted by a signal, the global 'rndc_task'
variable may already be detached from (set to NULL) by the time the
outstanding netmgr callbacks are run.  This triggers an assertion
failure in isc_task_shutdown().  However, explicitly calling
isc_task_shutdown() from rndc code is redundant because it does not use
isc_task_onshutdown() and the task_shutdown() function gets
automatically called anyway when the task manager gets destroyed (after
isc_app_run() returns).  Remove the redundant isc_task_shutdown() calls
to prevent crashes after receiving a signal.
---

diff --git a/bin/rndc/rndc.c b/bin/rndc/rndc.c
index c6e3212f685..f25db5a80ad 100644
--- a/bin/rndc/rndc.c
+++ b/bin/rndc/rndc.c
@@ -307,7 +307,6 @@ rndc_senddone(isc_nmhandle_t *handle, isc_result_t result, void *arg) {
 	    atomic_load_acquire(&recvs) == 0)
 	{
 		shuttingdown = true;
-		isc_task_shutdown(rndc_task);
 		isc_app_shutdown();
 	}
 }
@@ -393,7 +392,6 @@ rndc_recvdone(isc_nmhandle_t *handle, isc_result_t result, void *arg) {
 	    atomic_fetch_sub_release(&recvs, 1) == 1)
 	{
 		shuttingdown = true;
-		isc_task_shutdown(rndc_task);
 		isc_app_shutdown();
 	}
 }