File 0006-bgpd-Check-7-bytes-for-Long-lived-Graceful-Restart-c.patch of Package frr.33572

From d95229c9ba4c8ff99dfc644dd2d1e9e172fe3faf Mon Sep 17 00:00:00 2001
From: Donatas Abraitis <donatas@opensourcerouting.org>
Date: Fri, 24 Mar 2023 09:55:23 +0200
Upstream: yes
References: bsc#1211248,CVE-2023-31489,https://github.com/FRRouting/frr/pull/13100/commits/b1d33ec293e8e36fbb8766252f3b016d268e31ce
Subject: [PATCH] bgpd: Check 7 bytes for Long-lived Graceful-Restart
 capability

It's not 4 bytes, it was assuming the same as Graceful-Restart tuples.

LLGR has more 3 bytes (Long-lived Stale Time).

Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
Signed-off-by: Marius Tomaschewski <mt@suse.com>

diff --git a/bgpd/bgp_open.c b/bgpd/bgp_open.c
index d1667fac26..907e75e76b 100644
--- a/bgpd/bgp_open.c
+++ b/bgpd/bgp_open.c
@@ -599,12 +599,24 @@ static int bgp_capability_restart(struct peer *peer,
 static int bgp_capability_llgr(struct peer *peer,
 			       struct capability_header *caphdr)
 {
+/*
+ * +--------------------------------------------------+
+ * | Address Family Identifier (16 bits)              |
+ * +--------------------------------------------------+
+ * | Subsequent Address Family Identifier (8 bits)    |
+ * +--------------------------------------------------+
+ * | Flags for Address Family (8 bits)                |
+ * +--------------------------------------------------+
+ * | Long-lived Stale Time (24 bits)                  |
+ * +--------------------------------------------------+
+ */
+#define BGP_CAP_LLGR_MIN_PACKET_LEN 7
 	struct stream *s = BGP_INPUT(peer);
 	size_t end = stream_get_getp(s) + caphdr->length;
 
 	SET_FLAG(peer->cap, PEER_CAP_LLGR_RCV);
 
-	while (stream_get_getp(s) + 4 <= end) {
+	while (stream_get_getp(s) + BGP_CAP_LLGR_MIN_PACKET_LEN <= end) {
 		afi_t afi;
 		safi_t safi;
 		iana_afi_t pkt_afi = stream_getw(s);
-- 
2.35.3