From fcd7ad52d7ea361ed6b40191328676ee345105f6 Mon Sep 17 00:00:00 2001
From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Fri, 1 Oct 2021 17:59:56 +0900
Subject: [PATCH] network: radv: ignore Assign= if prefixlen is larger than 64

---
 src/network/networkd-radv.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/network/networkd-radv.c b/src/network/networkd-radv.c
index dabd91c0f9..b9ba0ff9ba 100644
--- a/src/network/networkd-radv.c
+++ b/src/network/networkd-radv.c
@@ -215,6 +215,17 @@ int link_request_radv_addresses(Link *link) {
                 if (r < 0)
                         return r;
 
+                /* generate_eui64_address() below requires the prefix length <= 64. */
+                if (prefixlen > 64) {
+                        _cleanup_free_ char *str = NULL;
+
+                        (void) in6_addr_prefix_to_string(&prefix, prefixlen, &str);
+                        log_link_debug(link,
+                                       "Prefix is longer than 64, refusing to assign an address in %s.",
+                                       strna(str));
+                        continue;
+                }
+
                 r = address_new(&address);
                 if (r < 0)
                         return log_oom();