From: Alan T. DeKok <aland@freeradius.org>
Date: Sat, 3 Apr 2021 12:06:10 +0000 (-0400)
Subject: retry on insert failure, due to mutex issues
X-Git-Tag: release_3_0_24~138
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fe28486a2dc55c6df83d88c15887c110eca0d2c7;p=thirdparty%2Ffreeradius-server.git

retry on insert failure, due to mutex issues
---

diff --git a/src/main/listen.c b/src/main/listen.c
index 6050142cf2b..6dbac3b7919 100644
--- a/src/main/listen.c
+++ b/src/main/listen.c
@@ -3778,6 +3778,7 @@ void listen_coa_free(void)
  */
 void listen_coa_add(rad_listen_t *this, char const *key)
 {
+	int trues = 0;
 	coa_key_t my_key, *coa_key;
 
 	rad_assert(this->send_coa);
@@ -3788,6 +3789,8 @@ void listen_coa_add(rad_listen_t *this, char const *key)
 	 *	Find the key.  If we can't find it, then create it.
 	 */
 	memcpy(&my_key.key, &key, sizeof(key)); /* const issues */
+
+retry:
 	coa_key = rbtree_finddata(coa_tree, &my_key);
 	if (!coa_key) {
 		coa_key = talloc_zero(NULL, coa_key_t);
@@ -3801,6 +3804,16 @@ void listen_coa_add(rad_listen_t *this, char const *key)
 
 		if (!rbtree_insert(coa_tree, coa_key)) {
 			talloc_free(coa_key);
+
+			/*
+			 *	The lookups are mutex protected, but
+			 *	if there's time between the lookup and
+			 *	the insert, another thread may have
+			 *	created the node.  In which case we
+			 *	try again.
+			 */
+			if (tries < 3) goto retry;
+			tries++;
 			return;
 		}
 	}