From: Mark Andrews <marka@isc.org>
Date: Wed, 7 Jul 2021 05:47:59 +0000 (+1000)
Subject: Fix unchecked return of isc_rwlock_lock and isc_rwlock_unlock
X-Git-Tag: v9.17.17~35^2~1
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=ce5207699d9c37c46d29d91c295947443c425861;p=thirdparty%2Fbind9.git

Fix unchecked return of isc_rwlock_lock and isc_rwlock_unlock

(cherry picked from commit bcaf23dd2799e30cfee1b5d39dec0fbc8e5f7193)
---

diff --git a/bin/dnssec/dnssec-signzone.c b/bin/dnssec/dnssec-signzone.c
index e321295684d..6cea5138d21 100644
--- a/bin/dnssec/dnssec-signzone.c
+++ b/bin/dnssec/dnssec-signzone.c
@@ -126,7 +126,7 @@ struct signer_event {
 
 static dns_dnsseckeylist_t keylist;
 static unsigned int keycount = 0;
-isc_rwlock_t keylist_lock;
+static isc_rwlock_t keylist_lock;
 static isc_stdtime_t starttime = 0, endtime = 0, dnskey_endtime = 0, now;
 static int cycle = -1;
 static int jitter = 0;
@@ -385,9 +385,9 @@ keythatsigned(dns_rdata_rrsig_t *rrsig) {
 	dst_key_t *pubkey = NULL, *privkey = NULL;
 	dns_dnsseckey_t *key = NULL;
 
-	isc_rwlock_lock(&keylist_lock, isc_rwlocktype_read);
+	RWLOCK(&keylist_lock, isc_rwlocktype_read);
 	key = keythatsigned_unlocked(rrsig);
-	isc_rwlock_unlock(&keylist_lock, isc_rwlocktype_read);
+	RWUNLOCK(&keylist_lock, isc_rwlocktype_read);
 	if (key != NULL) {
 		return (key);
 	}
diff --git a/lib/isc/rwlock.c b/lib/isc/rwlock.c
index 7984a630422..9f732b3aaa7 100644
--- a/lib/isc/rwlock.c
+++ b/lib/isc/rwlock.c
@@ -112,9 +112,12 @@ isc_rwlock_tryupgrade(isc_rwlock_t *rwl) {
 
 void
 isc_rwlock_downgrade(isc_rwlock_t *rwl) {
+	isc_result_t result;
 	atomic_store_release(&rwl->downgrade, true);
-	isc_rwlock_unlock(rwl, isc_rwlocktype_write);
-	isc_rwlock_lock(rwl, isc_rwlocktype_read);
+	result = isc_rwlock_unlock(rwl, isc_rwlocktype_write);
+	RUNTIME_CHECK(result == ISC_R_SUCCESS);
+	result = isc_rwlock_lock(rwl, isc_rwlocktype_read);
+	RUNTIME_CHECK(result == ISC_R_SUCCESS);
 	atomic_store_release(&rwl->downgrade, false);
 }