From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Wed, 17 Feb 2021 10:06:36 +0000 (+0900)
Subject: in-addr-util: make in_addr_prefix_nth() refuse prefixlen larger than maximum size
X-Git-Tag: v248-rc1~79^2~3
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7b6b05cff9b4927fca5e31f9faeb655e1287e3dc;p=thirdparty%2Fsystemd.git

in-addr-util: make in_addr_prefix_nth() refuse prefixlen larger than maximum size
---

diff --git a/src/basic/in-addr-util.c b/src/basic/in-addr-util.c
index 076b29ae9f6..343f62c5dc1 100644
--- a/src/basic/in-addr-util.c
+++ b/src/basic/in-addr-util.c
@@ -222,8 +222,9 @@ int in_addr_prefix_nth(int family, union in_addr_union *u, unsigned prefixlen, u
 
         if (family == AF_INET) {
                 uint32_t c, n, t;
+
                 if (prefixlen > 32)
-                        prefixlen = 32;
+                        return -ERANGE;
 
                 c = be32toh(u->in.s_addr);
 
@@ -247,7 +248,7 @@ int in_addr_prefix_nth(int family, union in_addr_union *u, unsigned prefixlen, u
                 unsigned start_byte = (prefixlen - 1) / 8;
 
                 if (prefixlen > 128)
-                        prefixlen = 128;
+                        return -ERANGE;
 
                 /* First calculate what we have to add */
                 delta = nth << ((128 - prefixlen) % 8);