From: Tomas Krizek <tomas.krizek@nic.cz>
Date: Wed, 26 Aug 2020 11:13:51 +0000 (+0200)
Subject: daemon/io: don't notify worker on udp_recv() errors
X-Git-Tag: v5.2.0~32^2~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=82e74cf697204ee082dcf96e9fab1208d5bfcc0e;p=thirdparty%2Fknot-resolver.git

daemon/io: don't notify worker on udp_recv() errors

The action doesn't increase any counter or do any error handling.
It would simply SEGFAULT. Even if it didn't worker_submit() would
just return an error code.
---

diff --git a/daemon/io.c b/daemon/io.c
index 48d264078..1c879188d 100644
--- a/daemon/io.c
+++ b/daemon/io.c
@@ -61,18 +61,9 @@ void udp_recv(uv_udp_t *handle, ssize_t nread, const uv_buf_t *buf,
 	const struct sockaddr *addr, unsigned flags)
 {
 	struct session *s = handle->data;
-	if (session_flags(s)->closing) {
-		return;
-	}
-	if (nread <= 0) {
-		if (nread < 0) { /* Error response, notify resolver */
-			worker_submit(s, NULL, NULL);
-		} /* nread == 0 is for freeing buffers, we don't need to do this */
+	if (session_flags(s)->closing || nread <= 0 || addr->sa_family == AF_UNSPEC)
 		return;
-	}
-	if (addr->sa_family == AF_UNSPEC) {
-		return;
-	}
+
 	if (session_flags(s)->outgoing) {
 		const struct sockaddr *peer = session_get_peer(s);
 		assert(peer->sa_family != AF_UNSPEC);
diff --git a/daemon/worker.c b/daemon/worker.c
index 41c803760..45ab8133d 100644
--- a/daemon/worker.c
+++ b/daemon/worker.c
@@ -1583,14 +1583,12 @@ int worker_submit(struct session *session, const struct sockaddr *peer, knot_pkt
 		return kr_error(EINVAL);
 	}
 
-	/* Parse packet */
 	int ret = parse_packet(query);
 
 	const bool is_query = (knot_wire_get_qr(query->wire) == 0);
 	const bool is_outgoing = session_flags(session)->outgoing;
 	/* Ignore badly formed queries. */
-	if (!query ||
-	    (ret != kr_ok() && ret != kr_error(EMSGSIZE)) ||
+	if ((ret != kr_ok() && ret != kr_error(EMSGSIZE)) ||
 	    (is_query == is_outgoing)) {
 		if (query && !is_outgoing) the_worker->stats.dropped += 1;
 		return kr_error(EILSEQ);