|
 |
814232 |
From 4757898440d52b0adbf7ec7ee7f0f89b61aac0fb Mon Sep 17 00:00:00 2001
|
|
|
814232 |
From: Mark Andrews <marka@isc.org>
|
|
|
814232 |
Date: Fri, 18 Dec 2020 13:31:07 +1100
|
|
|
814232 |
Subject: [PATCH] Inactive incorrectly incremented
|
|
|
814232 |
|
|
|
814232 |
It is possible to have two threads destroying an rbtdb at the same
|
|
|
814232 |
time when detachnode() executes and removes the last reference to
|
|
|
814232 |
a node between exiting being set to true for the node and testing
|
|
|
814232 |
if the references are zero in maybe_free_rbtdb(). Move NODE_UNLOCK()
|
|
|
814232 |
to after checking if references is zero to prevent detachnode()
|
|
|
814232 |
changing the reference count too early.
|
|
|
814232 |
|
|
|
814232 |
(cherry picked from commit 859d2fdad6d1c6ff20083a4c463a929cbeb26438)
|
|
|
814232 |
(cherry picked from commit 25150c15e7cfa73289f04470e2e699ebb7c28fef)
|
|
|
814232 |
---
|
|
|
814232 |
lib/dns/rbtdb.c | 2 +-
|
|
|
814232 |
1 file changed, 1 insertion(+), 1 deletion(-)
|
|
|
814232 |
|
|
|
814232 |
diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
|
|
|
814232 |
index 8ea4d47..77ef7a4 100644
|
|
|
814232 |
--- a/lib/dns/rbtdb.c
|
|
|
814232 |
+++ b/lib/dns/rbtdb.c
|
|
|
814232 |
@@ -1460,11 +1460,11 @@ maybe_free_rbtdb(dns_rbtdb_t *rbtdb) {
|
|
|
814232 |
for (i = 0; i < rbtdb->node_lock_count; i++) {
|
|
|
814232 |
NODE_LOCK(&rbtdb->node_locks[i].lock, isc_rwlocktype_write);
|
|
|
814232 |
rbtdb->node_locks[i].exiting = true;
|
|
|
814232 |
- NODE_UNLOCK(&rbtdb->node_locks[i].lock, isc_rwlocktype_write);
|
|
|
814232 |
if (isc_refcount_current(&rbtdb->node_locks[i].references)
|
|
|
814232 |
== 0) {
|
|
|
814232 |
inactive++;
|
|
|
814232 |
}
|
|
|
814232 |
+ NODE_UNLOCK(&rbtdb->node_locks[i].lock, isc_rwlocktype_write);
|
|
|
814232 |
}
|
|
|
814232 |
|
|
|
814232 |
if (inactive != 0) {
|
|
|
814232 |
--
|
|
|
814232 |
2.26.3
|
|
|
814232 |
|