From: Vladimír Čunát <vladimir.cunat@nic.cz>
Date: Fri, 21 May 2021 15:29:25 +0000 (+0200)
Subject: lib/selection: be more careful with RO transactions
X-Git-Tag: v5.4.0~12^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a23bb067a33d371d04a0ef6f55dd49adabb4023c;p=thirdparty%2Fknot-resolver.git

lib/selection: be more careful with RO transactions

They probably couldn't hang open for long, as each client request
should cause some cache-searching and thus close it, and even with
queries stopping I haven't managed to find a case where it would be
left open but... it's nicer to clean up and it should be very cheap.
---

diff --git a/lib/selection.h b/lib/selection.h
index 02ef5b5a1..39261557d 100644
--- a/lib/selection.h
+++ b/lib/selection.h
@@ -254,6 +254,9 @@ uint8_t *ip_to_bytes(const union inaddr *src, size_t len);
 
 /**
  * @internal Fetch per-address information from various sources.
+ *
+ * Note that this opens a RO cache transaction; the callee is responsible
+ * for its closing not too long afterwards (e.g. calling kr_cache_commit).
  */
 void update_address_state(struct address_state *state, union inaddr *address,
 			  size_t address_len, struct kr_query *qry);
diff --git a/lib/selection_forward.c b/lib/selection_forward.c
index ea2ec6ecf..cde634d56 100644
--- a/lib/selection_forward.c
+++ b/lib/selection_forward.c
@@ -53,7 +53,7 @@ void forward_choose_transport(struct kr_query *qry,
 		default:
 			kr_assert(false);
 			*transport = NULL;
-			return;
+			goto cleanup;
 		}
 
 		struct address_state *addr_state = &local_state->addr_states[i];
@@ -94,6 +94,8 @@ void forward_choose_transport(struct kr_query *qry,
 		qry->flags.TCP = (*transport)->protocol == KR_TRANSPORT_TCP
 			      || (*transport)->protocol == KR_TRANSPORT_TLS;
 	}
+cleanup:
+	kr_cache_commit(&qry->request->ctx->cache);
 }
 
 void forward_error(struct kr_query *qry, const struct kr_transport *transport,
diff --git a/lib/selection_iter.c b/lib/selection_iter.c
index b5b241c15..87206cc01 100644
--- a/lib/selection_iter.c
+++ b/lib/selection_iter.c
@@ -127,6 +127,7 @@ static void unpack_state_from_zonecut(struct iter_local_state *local_state,
 		}
 	}
 	trie_it_free(it);
+	kr_cache_commit(&qry->request->ctx->cache);
 }
 
 static int get_valid_addresses(struct iter_local_state *local_state,