diff --git a/lib/dns/include/dns/rdataslab.h b/lib/dns/include/dns/rdataslab.h
index c5e61c3b92..b93619f600 100644
--- a/lib/dns/include/dns/rdataslab.h
+++ b/lib/dns/include/dns/rdataslab.h
@@ -295,14 +295,14 @@ void
 dns_slabheader_reset(dns_slabheader_t *h, dns_dbnode_t *node);
 /*%<
  * Reset an rdataslab header 'h' so it can be used to store data in
- * database 'db' and node 'node'.
+ * database node 'node'.
  */
 
 dns_slabheader_t *
-dns_slabheader_new(dns_db_t *db, dns_dbnode_t *node);
+dns_slabheader_new(isc_mem_t *mctx, dns_dbnode_t *node);
 /*%<
  * Allocate memory for an rdataslab header and initialize it for use
- * in database 'db'/node 'node'.
+ * in database node 'node'.
  */
 
 void
diff --git a/lib/dns/qpcache.c b/lib/dns/qpcache.c
index 8a2cd03879..93ae06cd18 100644
--- a/lib/dns/qpcache.c
+++ b/lib/dns/qpcache.c
@@ -3163,7 +3163,7 @@ qpcache_deleterdataset(dns_db_t *db, dns_dbnode_t *node,
 		return ISC_R_NOTIMPLEMENTED;
 	}
 
-	newheader = dns_slabheader_new(db, node);
+	newheader = dns_slabheader_new(db->mctx, node);
 	newheader->typepair = DNS_TYPEPAIR_VALUE(type, covers);
 	setttl(newheader, 0);
 	atomic_init(&newheader->attributes, attributes);
diff --git a/lib/dns/qpzone.c b/lib/dns/qpzone.c
index 76eb96c9d5..10d1065e12 100644
--- a/lib/dns/qpzone.c
+++ b/lib/dns/qpzone.c
@@ -5026,7 +5026,7 @@ qpzone_subtractrdataset(dns_db_t *db, dns_dbnode_t *dbnode,
 			 * add a nonexistent header instead.
 			 */
 			dns_slabheader_destroy(&newheader);
-			newheader = dns_slabheader_new((dns_db_t *)qpdb,
+			newheader = dns_slabheader_new(db->mctx,
 						       (dns_dbnode_t *)node);
 			newheader->ttl = 0;
 			newheader->typepair = topheader->typepair;
@@ -5110,7 +5110,7 @@ qpzone_deleterdataset(dns_db_t *db, dns_dbnode_t *dbnode,
 		return ISC_R_NOTIMPLEMENTED;
 	}
 
-	newheader = dns_slabheader_new(db, (dns_dbnode_t *)node);
+	newheader = dns_slabheader_new(db->mctx, (dns_dbnode_t *)node);
 	newheader->typepair = DNS_TYPEPAIR_VALUE(type, covers);
 	newheader->ttl = 0;
 	atomic_init(&newheader->attributes, DNS_SLABHEADERATTR_NONEXISTENT);
diff --git a/lib/dns/rdataslab.c b/lib/dns/rdataslab.c
index 35645b66e3..c175f449a0 100644
--- a/lib/dns/rdataslab.c
+++ b/lib/dns/rdataslab.c
@@ -886,14 +886,14 @@ dns_slabheader_reset(dns_slabheader_t *h, dns_dbnode_t *node) {
 }
 
 dns_slabheader_t *
-dns_slabheader_new(dns_db_t *db, dns_dbnode_t *node) {
+dns_slabheader_new(isc_mem_t *mctx, dns_dbnode_t *node) {
 	dns_slabheader_t *h = NULL;
 
-	h = isc_mem_get(db->mctx, sizeof(*h));
+	h = isc_mem_get(mctx, sizeof(*h));
 	*h = (dns_slabheader_t){
 		.link = ISC_LINK_INITIALIZER,
+		.node = node,
 	};
-	dns_slabheader_reset(h, node);
 	return h;
 }