From: Roy Marples <roy@marples.name>
Date: Sat, 4 May 2019 09:19:02 +0000 (+0100)
Subject: DHCPv6: Fix exclude prefix length check.
X-Git-Tag: v7.2.2^0
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d30538898e39cc9a49ced4e67e91013d1d84a2c2;p=thirdparty%2Fdhcpcd.git

DHCPv6: Fix exclude prefix length check.
---

diff --git a/src/dhcp6.c b/src/dhcp6.c
index 583f3b3f..7f26129f 100644
--- a/src/dhcp6.c
+++ b/src/dhcp6.c
@@ -2187,14 +2187,14 @@ dhcp6_findpd(struct interface *ifp, const uint8_t *iaid,
 			continue;
 		}
 
+		ol--;
 		/* Check option length matches prefix length. */
 		if (((*o - a->prefix_len - 1) / NBBY) + 1 != ol) {
 			logerrx("%s: PD Exclude length mismatch", ifp->name);
 			continue;
 		}
-
 		a->prefix_exclude_len = *o++;
-		ol--;
+
 		memcpy(&a->prefix_exclude, &a->prefix,
 		    sizeof(a->prefix_exclude));
 		nb = a->prefix_len % NBBY;