From: Hans Dedecker <dedeckeh@gmail.com>
Date: Fri, 27 Dec 2013 14:49:44 +0000 (+0100)
Subject: Revert "Fix handling of DHCPv6 messages containing option lengths exceeding the message"
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=68ac18ed5d5b4c2d403396764f08c92a160b4a18;p=project%2Fodhcp6c.git

Revert "Fix handling of DHCPv6 messages containing option lengths exceeding the message"

This reverts commit 26c5d8724355b29694af684ee29b47e52129a33c.
---

diff --git a/src/dhcpv6.c b/src/dhcpv6.c
index 75bc50e..cd8e438 100644
--- a/src/dhcpv6.c
+++ b/src/dhcpv6.c
@@ -569,11 +569,7 @@ static bool dhcpv6_response_is_valid(const void *buf, ssize_t len,
 	void *server_id = odhcp6c_get_state(STATE_SERVER_ID, &server_id_len);
 
 	dhcpv6_for_each_option(&rep[1], end, otype, olen, odata) {
-		if ((odata + olen) > end) {
-			options_valid = false;
-			break;
-		}
-		else if (otype == DHCPV6_OPT_CLIENTID) {
+		if (otype == DHCPV6_OPT_CLIENTID) {
 			clientid_ok = (olen + 4U == client_id_len) && !memcmp(
 					&odata[-4], client_id, client_id_len);
 		} else if (otype == DHCPV6_OPT_SERVERID) {
diff --git a/src/odhcp6c.h b/src/odhcp6c.h
index 8771521..15be59a 100644
--- a/src/odhcp6c.h
+++ b/src/odhcp6c.h
@@ -155,7 +155,7 @@ struct dhcpv6_auth_reconfigure {
 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
 	for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
 		((otype) = _o[0] << 8 | _o[1]) && ((odata) = (void*)&_o[4]) &&\
-		 ((olen) = _o[2] << 8 | _o[3]); \
+		((olen) = _o[2] << 8 | _o[3]) + (odata) <= (uint8_t*)(end); \
 		_o += 4 + (_o[2] << 8 | _o[3]))