From: Roy Marples <roy@marples.name>
Date: Tue, 15 Oct 2019 10:57:17 +0000 (+0100)
Subject: dhcp: Allow for trailing FCS in the packet.
X-Git-Tag: v8.1.1~10
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f9b3ad2c6a80bbdd111a869e3d38e179e8ce4b8e;p=thirdparty%2Fdhcpcd.git

dhcp: Allow for trailing FCS in the packet.
---

diff --git a/src/dhcp.c b/src/dhcp.c
index ed0ffa48..67bf4566 100644
--- a/src/dhcp.c
+++ b/src/dhcp.c
@@ -3282,7 +3282,7 @@ is_packet_udp_bootp(void *packet, size_t plen)
 		return false;
 
 	/* Sanity. */
-	if (ntohs(ip->ip_len) != plen)
+	if (ntohs(ip->ip_len) > plen)
 		return false;
 
 	ip_hlen = (size_t)ip->ip_hl * 4;
@@ -3297,7 +3297,7 @@ is_packet_udp_bootp(void *packet, size_t plen)
 	udp = (struct udphdr *)(void *)((char *)ip + ip_hlen);
 	if (ntohs(udp->uh_ulen) < sizeof(*udp))
 		return false;
-	if (ip_hlen + ntohs(udp->uh_ulen) != plen)
+	if (ip_hlen + ntohs(udp->uh_ulen) > plen)
 		return false;
 
 	/* Check it's to and from the right ports. */