frr/0025-CVE-2023-31490.patch

151 lines
5.4 KiB
Diff

From 06431bfa7570f169637ebb5898f0b0cc3b010802 Mon Sep 17 00:00:00 2001
From: Donald Sharp <sharpd@nvidia.com>
Date: Tue, 6 Dec 2022 10:23:11 -0500
Subject: [PATCH] bgpd: Ensure stream received has enough data
BGP_PREFIX_SID_SRV6_L3_SERVICE attributes must not
fully trust the length value specified in the nlri.
Always ensure that the amount of data we need to read
can be fullfilled.
Reported-by: Iggy Frankovic <iggyfran@amazon.com>
Signed-off-by: Donald Sharp <sharpd@nvidia.com>
---
bgpd/bgp_attr.c | 79 ++++++++++++++++---------------------------------
1 file changed, 25 insertions(+), 54 deletions(-)
diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c
index c35e45275c9b..5b06bc391375 100644
--- a/bgpd/bgp_attr.c
+++ b/bgpd/bgp_attr.c
@@ -2927,9 +2927,21 @@ bgp_attr_psid_sub(uint8_t type, uint16_t length,
uint16_t endpoint_behavior;
char buf[BUFSIZ];
+ /*
+ * Check that we actually have at least as much data as
+ * specified by the length field
+ */
+ if (STREAM_READABLE(peer->curr) < length) {
+ flog_err(
+ EC_BGP_ATTR_LEN,
+ "Prefix SID specifies length %hu, but only %zu bytes remain",
+ length, STREAM_READABLE(peer->curr));
+ return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
+ args->total);
+ }
+
if (type == BGP_PREFIX_SID_LABEL_INDEX) {
- if (STREAM_READABLE(peer->curr) < length
- || length != BGP_PREFIX_SID_LABEL_INDEX_LENGTH) {
+ if (length != BGP_PREFIX_SID_LABEL_INDEX_LENGTH) {
flog_err(EC_BGP_ATTR_LEN,
"Prefix SID label index length is %hu instead of %u",
length, BGP_PREFIX_SID_LABEL_INDEX_LENGTH);
@@ -2951,12 +2963,8 @@ bgp_attr_psid_sub(uint8_t type, uint16_t length,
/* Store label index; subsequently, we'll check on
* address-family */
attr->label_index = label_index;
- }
-
- /* Placeholder code for the IPv6 SID type */
- else if (type == BGP_PREFIX_SID_IPV6) {
- if (STREAM_READABLE(peer->curr) < length
- || length != BGP_PREFIX_SID_IPV6_LENGTH) {
+ } else if (type == BGP_PREFIX_SID_IPV6) {
+ if (length != BGP_PREFIX_SID_IPV6_LENGTH) {
flog_err(EC_BGP_ATTR_LEN,
"Prefix SID IPv6 length is %hu instead of %u",
length, BGP_PREFIX_SID_IPV6_LENGTH);
@@ -2970,10 +2978,7 @@ bgp_attr_psid_sub(uint8_t type, uint16_t length,
stream_getw(peer->curr);
stream_get(&ipv6_sid, peer->curr, 16);
- }
-
- /* Placeholder code for the Originator SRGB type */
- else if (type == BGP_PREFIX_SID_ORIGINATOR_SRGB) {
+ } else if (type == BGP_PREFIX_SID_ORIGINATOR_SRGB) {
/*
* ietf-idr-bgp-prefix-sid-05:
* Length is the total length of the value portion of the
@@ -2998,19 +3003,6 @@ bgp_attr_psid_sub(uint8_t type, uint16_t length,
args->total);
}
- /*
- * Check that we actually have at least as much data as
- * specified by the length field
- */
- if (STREAM_READABLE(peer->curr) < length) {
- flog_err(EC_BGP_ATTR_LEN,
- "Prefix SID Originator SRGB specifies length %hu, but only %zu bytes remain",
- length, STREAM_READABLE(peer->curr));
- return bgp_attr_malformed(
- args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
- args->total);
- }
-
/*
* Check that the portion of the TLV containing the sequence of
* SRGBs corresponds to a multiple of the SRGB size; to get
@@ -3034,12 +3026,8 @@ bgp_attr_psid_sub(uint8_t type, uint16_t length,
stream_get(&srgb_base, peer->curr, 3);
stream_get(&srgb_range, peer->curr, 3);
}
- }
-
- /* Placeholder code for the VPN-SID Service type */
- else if (type == BGP_PREFIX_SID_VPN_SID) {
- if (STREAM_READABLE(peer->curr) < length
- || length != BGP_PREFIX_SID_VPN_SID_LENGTH) {
+ } else if (type == BGP_PREFIX_SID_VPN_SID) {
+ if (length != BGP_PREFIX_SID_VPN_SID_LENGTH) {
flog_err(EC_BGP_ATTR_LEN,
"Prefix SID VPN SID length is %hu instead of %u",
length, BGP_PREFIX_SID_VPN_SID_LENGTH);
@@ -2601,18 +2589,13 @@ static bgp_attr_parse_ret_t bgp_attr_psid_sub(uint8_t type, uint16_t length,
sizeof(struct bgp_attr_srv6_vpn));
attr->srv6_vpn->sid_flags = sid_flags;
sid_copy(&attr->srv6_vpn->sid, &ipv6_sid);
- }
-
- /* Placeholder code for the SRv6 L3 Service type */
- else if (type == BGP_PREFIX_SID_SRV6_L3_SERVICE) {
- if (STREAM_READABLE(peer->curr) < length
- || length != BGP_PREFIX_SID_SRV6_L3_SERVICE_LENGTH) {
- flog_err(EC_BGP_ATTR_LEN,
- "Prefix SID SRv6 L3-Service length is %hu instead of %u",
- length, BGP_PREFIX_SID_SRV6_L3_SERVICE_LENGTH);
- return bgp_attr_malformed(args,
- BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
- args->total);
+ } else if (type == BGP_PREFIX_SID_SRV6_L3_SERVICE) {
+ if (STREAM_READABLE(peer->curr) < 1) {
+ flog_err(EC_BGP_ATTR_LEN,
+ "Prefix SID SRV6 L3 Service not enough data left, it must be at least 1 byte");
+ return bgp_attr_malformed(
+ args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
+ args->total);
}
/* Parse L3-SERVICE Sub-TLV */
@@ -2647,17 +2630,6 @@ static bgp_attr_parse_ret_t bgp_attr_psid_sub(uint8_t type, uint16_t length,
/* Placeholder code for Unsupported TLV */
else {
-
- if (STREAM_READABLE(peer->curr) < length) {
- flog_err(
- EC_BGP_ATTR_LEN,
- "Prefix SID SRv6 length is %hu - too long, only %zu remaining in this UPDATE",
- length, STREAM_READABLE(peer->curr));
- return bgp_attr_malformed(
- args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
- args->total);
- }
-
if (bgp_debug_update(peer, NULL, NULL, 1))
zlog_debug(
"%s attr Prefix-SID sub-type=%u is not supported, skipped",