From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Thu, 22 Feb 2024 05:33:29 +0000 (+0900)
Subject: sd-ndisc: actually refuse RA message from null address
X-Git-Tag: v256-rc1~770^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=189eeddaecb40881c3a86f263085b972ed2dc08b;p=thirdparty%2Fsystemd.git

sd-ndisc: actually refuse RA message from null address
---

diff --git a/src/libsystemd-network/sd-ndisc.c b/src/libsystemd-network/sd-ndisc.c
index 9b2635ae1cd..ac31d212e39 100644
--- a/src/libsystemd-network/sd-ndisc.c
+++ b/src/libsystemd-network/sd-ndisc.c
@@ -252,8 +252,10 @@ static int ndisc_recv(sd_event_source *s, int fd, uint32_t revents, void *userda
 
         /* The function icmp6_receive() accepts the null source address, but RFC 4861 Section 6.1.2 states
          * that hosts MUST discard messages with the null source address. */
-        if (in6_addr_is_null(&rt->address))
-                log_ndisc(nd, "Received RA from null address. Ignoring.");
+        if (in6_addr_is_null(&rt->address)) {
+                log_ndisc(nd, "Received an ICMPv6 packet from null address, ignoring.");
+                return 0;
+        }
 
         (void) ndisc_handle_datagram(nd, rt);
         return 0;