systemd/backport-resolved-fix-use-of-ERRNO_IS_DISCONNECT.patch
2023-12-18 17:29:00 +08:00

67 lines
3.0 KiB
Diff

From 0bdea17c0aa37c4cdf586c072a7b35f8d0598cc3 Mon Sep 17 00:00:00 2001
From: "Dmitry V. Levin" <ldv@strace.io>
Date: Fri, 7 Jul 2023 08:00:00 +0000
Subject: [PATCH] resolved: fix use of ERRNO_IS_DISCONNECT()
Given that ERRNO_IS_DISCONNECT() also matches positive values,
make sure this macro is not called with arguments that do not have
errno semantics.
In this case the argument passed to ERRNO_IS_DISCONNECT() is the value
returned by manager_recv() which can legitimately return 1 without errno
semantics, so fix this by moving ERRNO_IS_DISCONNECT() invocation to the
branch where the return value is known to be negative.
Conflict:NA
Reference:https://github.com/systemd/systemd-stable/commit/0bdea17c0aa37c4cdf586c072a7b35f8d0598cc3
---
src/resolve/resolved-dns-transaction.c | 27 ++++++++++++--------------
1 file changed, 12 insertions(+), 15 deletions(-)
diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
index a5293357c0..323786896b 100644
--- a/src/resolve/resolved-dns-transaction.c
+++ b/src/resolve/resolved-dns-transaction.c
@@ -1367,25 +1367,22 @@ static int on_dns_packet(sd_event_source *s, int fd, uint32_t revents, void *use
assert(t->scope);
r = manager_recv(t->scope->manager, fd, DNS_PROTOCOL_DNS, &p);
- if (ERRNO_IS_DISCONNECT(r)) {
- usec_t usec;
-
- /* UDP connection failures get reported via ICMP and then are possibly delivered to us on the
- * next recvmsg(). Treat this like a lost packet. */
+ if (r < 0) {
+ if (ERRNO_IS_DISCONNECT(r)) {
+ usec_t usec;
- log_debug_errno(r, "Connection failure for DNS UDP packet: %m");
- assert_se(sd_event_now(t->scope->manager->event, CLOCK_BOOTTIME, &usec) >= 0);
- dns_server_packet_lost(t->server, IPPROTO_UDP, t->current_feature_level);
+ /* UDP connection failures get reported via ICMP and then are possibly delivered to us on the
+ * next recvmsg(). Treat this like a lost packet. */
- dns_transaction_close_connection(t, /* use_graveyard = */ false);
+ log_debug_errno(r, "Connection failure for DNS UDP packet: %m");
+ assert_se(sd_event_now(t->scope->manager->event, CLOCK_BOOTTIME, &usec) >= 0);
+ dns_server_packet_lost(t->server, IPPROTO_UDP, t->current_feature_level);
- if (dns_transaction_limited_retry(t)) /* Try a different server */
- return 0;
+ dns_transaction_close_connection(t, /* use_graveyard = */ false);
- dns_transaction_complete_errno(t, r);
- return 0;
- }
- if (r < 0) {
+ if (dns_transaction_limited_retry(t)) /* Try a different server */
+ return 0;
+ }
dns_transaction_complete_errno(t, r);
return 0;
}
--
2.39.1