c-ares/SOURCES/0004-Merge-pull-request-fro...

83 lines
2.7 KiB
Diff

From b9b8413cfdb70a3f99e1573333b23052d57ec1ae Mon Sep 17 00:00:00 2001
From: Brad House <brad@brad-house.com>
Date: Mon, 22 May 2023 06:51:49 -0400
Subject: [PATCH] Merge pull request from GHSA-9g78-jv2r-p7vc
---
ares_process.c | 41 +++++++++++++++++++++++++----------------
1 file changed, 25 insertions(+), 16 deletions(-)
diff --git a/ares_process.c b/ares_process.c
index bf0cde4..6cac0a9 100644
--- a/ares_process.c
+++ b/ares_process.c
@@ -470,7 +470,7 @@ static void read_udp_packets(ares_channel channel, fd_set *read_fds,
{
struct server_state *server;
int i;
- ares_ssize_t count;
+ ares_ssize_t read_len;
unsigned char buf[MAXENDSSZ + 1];
#ifdef HAVE_RECVFROM
ares_socklen_t fromlen;
@@ -513,32 +513,41 @@ static void read_udp_packets(ares_channel channel, fd_set *read_fds,
/* To reduce event loop overhead, read and process as many
* packets as we can. */
do {
- if (server->udp_socket == ARES_SOCKET_BAD)
- count = 0;
-
- else {
- if (server->addr.family == AF_INET)
+ if (server->udp_socket == ARES_SOCKET_BAD) {
+ read_len = -1;
+ } else {
+ if (server->addr.family == AF_INET) {
fromlen = sizeof(from.sa4);
- else
+ } else {
fromlen = sizeof(from.sa6);
- count = socket_recvfrom(channel, server->udp_socket, (void *)buf,
- sizeof(buf), 0, &from.sa, &fromlen);
+ }
+ read_len = socket_recvfrom(channel, server->udp_socket, (void *)buf,
+ sizeof(buf), 0, &from.sa, &fromlen);
}
- if (count == -1 && try_again(SOCKERRNO))
+ if (read_len == 0) {
+ /* UDP is connectionless, so result code of 0 is a 0-length UDP
+ * packet, and not an indication the connection is closed like on
+ * tcp */
continue;
- else if (count <= 0)
+ } else if (read_len < 0) {
+ if (try_again(SOCKERRNO))
+ continue;
+
handle_error(channel, i, now);
+
#ifdef HAVE_RECVFROM
- else if (!same_address(&from.sa, &server->addr))
+ } else if (!same_address(&from.sa, &server->addr)) {
/* The address the response comes from does not match the address we
* sent the request to. Someone may be attempting to perform a cache
* poisoning attack. */
- break;
+ continue;
#endif
- else
- process_answer(channel, buf, (int)count, i, 0, now);
- } while (count > 0);
+
+ } else {
+ process_answer(channel, buf, (int)read_len, i, 0, now);
+ }
+ } while (read_len >= 0);
}
}
--
2.38.1