File 0017-bgpd-Fix-use-beyond-end-of-stream-of-labeled-unicast.patch of Package frr.31712
From 6979aa1574167121e260120504c77b47bb25230e Mon Sep 17 00:00:00 2001
From: Donald Sharp <sharpd@nvidia.com>
Date: Fri, 3 Mar 2023 21:58:33 -0500
Subject: [PATCH] bgpd: Fix use beyond end of stream of labeled unicast parsing
Upstream: yes
CVE-2023-38407,bsc#1216899,https://github.com/FRRouting/frr/pull/12956/commits/ab362eae68edec12c175d9bc488bcc3f8b73d36f
Fixes a couple crashes associated with attempting to read
beyond the end of the stream.
Reported-by: Iggy Frankovic <iggyfran@amazon.com>
Signed-off-by: Donald Sharp <sharpd@nvidia.com>
(cherry picked from commit 7404a914b0cafe046703c8381903a80d3def8f8b)
Signed-off-by: Marius Tomaschewski <mt@suse.com>
diff --git a/bgpd/bgp_label.c b/bgpd/bgp_label.c
index 38f34a8927..64d1ff70ca 100644
--- a/bgpd/bgp_label.c
+++ b/bgpd/bgp_label.c
@@ -312,6 +312,9 @@ static int bgp_nlri_get_labels(struct peer *peer, uint8_t *pnt, uint8_t plen,
uint8_t llen = 0;
uint8_t label_depth = 0;
+ if (plen < BGP_LABEL_BYTES)
+ return 0;
+
for (; data < lim; data += BGP_LABEL_BYTES) {
memcpy(label, data, BGP_LABEL_BYTES);
llen += BGP_LABEL_BYTES;
@@ -374,6 +377,9 @@ int bgp_nlri_parse_label(struct peer *peer, struct attr *attr,
memcpy(&addpath_id, pnt, BGP_ADDPATH_ID_LEN);
addpath_id = ntohl(addpath_id);
pnt += BGP_ADDPATH_ID_LEN;
+
+ if (pnt >= lim)
+ return BGP_NLRI_PARSE_ERROR_PACKET_OVERFLOW;
}
/* Fetch prefix length. */
@@ -392,6 +398,15 @@ int bgp_nlri_parse_label(struct peer *peer, struct attr *attr,
/* Fill in the labels */
llen = bgp_nlri_get_labels(peer, pnt, psize, &label);
+ if (llen == 0) {
+ flog_err(
+ EC_BGP_UPDATE_RCV,
+ "%s [Error] Update packet error (wrong label length 0)",
+ peer->host);
+ bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
+ BGP_NOTIFY_UPDATE_INVAL_NETWORK);
+ return BGP_NLRI_PARSE_ERROR_LABEL_LENGTH;
+ }
p.prefixlen = prefixlen - BSIZE(llen);
/* There needs to be at least one label */
--
2.35.3
