rbtversion->glue_table_size must be read when holding a lock

(cherry picked from commit 33d0e8d168ff7483246fe1f80a7307eec334a63c)

diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
index 8de09d257e2a4a336250c82babab6ac196625e92..69b620476bddd0af686bee3306c068c729107c95 100644 (file)
--- a/lib/dns/rbtdb.c
+++ b/lib/dns/rbtdb.c
@@ -10049,7 +10049,10 @@ free_gluetable(rbtdb_version_t *version) {
        RWUNLOCK(&version->glue_rwlock, isc_rwlocktype_write);
 }
 
-static bool
+/*%
+ * Write lock (version->glue_rwlock) must be held.
+ */
+static void
 rehash_gluetable(rbtdb_version_t *version) {
        size_t oldsize, i;
        rbtdb_glue_table_node_t **oldtable;
@@ -10059,7 +10062,7 @@ rehash_gluetable(rbtdb_version_t *version) {
 
        if (ISC_LIKELY(version->glue_table_nodecount <
                       (version->glue_table_size * 3U))) {
-               return (false);
+               return;
        }
 
        oldsize = version->glue_table_size;
@@ -10077,7 +10080,7 @@ rehash_gluetable(rbtdb_version_t *version) {
        if (ISC_UNLIKELY(version->glue_table == NULL)) {
                version->glue_table = oldtable;
                version->glue_table_size = oldsize;
-               return (false);
+               return;
        }
 
        for (i = 0; i < version->glue_table_size; i++) {
@@ -10105,8 +10108,6 @@ rehash_gluetable(rbtdb_version_t *version) {
                      "resized glue table from %" PRIu64 " to "
                      "%" PRIu64,
                      (uint64_t)oldsize, (uint64_t)version->glue_table_size);
-
-       return (true);
 }
 
 static isc_result_t
@@ -10233,6 +10234,7 @@ rdataset_addglue(dns_rdataset_t *rdataset, dns_dbversion_t *version,
        rbtdb_glue_t *ge;
        rbtdb_glue_additionaldata_ctx_t ctx;
        isc_result_t result;
+       uint64_t hash;
 
        REQUIRE(rdataset->type == dns_rdatatype_ns);
        REQUIRE(rbtdb == rbtversion->rbtdb);
@@ -10250,8 +10252,7 @@ rdataset_addglue(dns_rdataset_t *rdataset, dns_dbversion_t *version,
         * the node pointer is a fixed value that won't change for a DB
         * version and can be compared directly.
         */
-       idx = isc_hash_function(&node, sizeof(node), true) %
-             rbtversion->glue_table_size;
+       hash = isc_hash_function(&node, sizeof(node), true);
 
 restart:
        /*
@@ -10260,6 +10261,8 @@ restart:
         */
        RWLOCK(&rbtversion->glue_rwlock, isc_rwlocktype_read);
 
+       idx = hash % rbtversion->glue_table_size;
+
        for (cur = rbtversion->glue_table[idx]; cur != NULL; cur = cur->next) {
                if (cur->node == node) {
                        break;
@@ -10423,10 +10426,8 @@ no_glue:
 
        RWLOCK(&rbtversion->glue_rwlock, isc_rwlocktype_write);
 
-       if (ISC_UNLIKELY(rehash_gluetable(rbtversion))) {
-               idx = isc_hash_function(&node, sizeof(node), true) %
-                     rbtversion->glue_table_size;
-       }
+       rehash_gluetable(rbtversion);
+       idx = hash % rbtversion->glue_table_size;
 
        (void)dns_rdataset_additionaldata(rdataset, glue_nsdname_cb, &ctx);