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[FRR] Adding patches for CVE-2023-41358 and CVE-2023-38802 (#16749)

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Created patches to address two CVEs from FRR CVE-2023-41358 and CVE-2023-38802.

Patch	FRR commit	CVE fixed
0024-bgpd-Do-not-process-NLRIs-if-the-attribute-length-is.patch	FRRouting/frr@f291f1e	CVE-2023-41358
0025-bgpd-Use-treat-as-withdraw-for-tunnel-encapsulation-.patch	FRRouting/frr@8a4a88c	CVE-2023-38802
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Sudharsan Dhamal Gopalarathnam 2023-09-29 09:17:17 -07:00 committed by GitHub
parent 0fc0fb2fdb
commit 81a2f56821
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97
src/sonic-frr/patch/0024-bgpd-Do-not-process-NLRIs-if-the-attribute-length-is.patch Normal file
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@ -0,0 +1,97 @@
From fc5cb12121cb1858c162f9ed8f6206fc61439455 Mon Sep 17 00:00:00 2001
From: Donatas Abraitis <donatas@opensourcerouting.org>
Date: Tue, 22 Aug 2023 22:52:04 +0300
Subject: [PATCH] bgpd: Do not process NLRIs if the attribute length is zero
```
3 0x00007f423aa42476 in __GI_raise (sig=sig@entry=11) at ../sysdeps/posix/raise.c:26
4 0x00007f423aef9740 in core_handler (signo=11, siginfo=0x7fffc414deb0, context=<optimized out>) at lib/sigevent.c:246
5 <signal handler called>
6 0x0000564dea2fc71e in route_set_aspath_prepend (rule=0x564debd66d50, prefix=0x7fffc414ea30, object=0x7fffc414e400)
at bgpd/bgp_routemap.c:2258
7 0x00007f423aeec7e0 in route_map_apply_ext (map=<optimized out>, prefix=prefix@entry=0x7fffc414ea30,
match_object=match_object@entry=0x7fffc414e400, set_object=set_object@entry=0x7fffc414e400, pref=pref@entry=0x0) at lib/routemap.c:2690
8 0x0000564dea2d277e in bgp_input_modifier (peer=peer@entry=0x7f4238f59010, p=p@entry=0x7fffc414ea30, attr=attr@entry=0x7fffc414e770,
afi=afi@entry=AFI_IP, safi=safi@entry=SAFI_UNICAST, rmap_name=rmap_name@entry=0x0, label=0x0, num_labels=0, dest=0x564debdd5130)
at bgpd/bgp_route.c:1772
9 0x0000564dea2df762 in bgp_update (peer=peer@entry=0x7f4238f59010, p=p@entry=0x7fffc414ea30, addpath_id=addpath_id@entry=0,
attr=0x7fffc414eb50, afi=afi@entry=AFI_IP, safi=<optimized out>, safi@entry=SAFI_UNICAST, type=9, sub_type=0, prd=0x0, label=0x0,
num_labels=0, soft_reconfig=0, evpn=0x0) at bgpd/bgp_route.c:4374
10 0x0000564dea2e2047 in bgp_nlri_parse_ip (peer=0x7f4238f59010, attr=attr@entry=0x7fffc414eb50, packet=0x7fffc414eaf0)
at bgpd/bgp_route.c:6249
11 0x0000564dea2c5a58 in bgp_nlri_parse (peer=peer@entry=0x7f4238f59010, attr=attr@entry=0x7fffc414eb50,
packet=packet@entry=0x7fffc414eaf0, mp_withdraw=mp_withdraw@entry=false) at bgpd/bgp_packet.c:339
12 0x0000564dea2c5d66 in bgp_update_receive (peer=peer@entry=0x7f4238f59010, size=size@entry=109) at bgpd/bgp_packet.c:2024
13 0x0000564dea2c901d in bgp_process_packet (thread=<optimized out>) at bgpd/bgp_packet.c:2933
14 0x00007f423af0bf71 in event_call (thread=thread@entry=0x7fffc414ee40) at lib/event.c:1995
15 0x00007f423aebb198 in frr_run (master=0x564deb73c670) at lib/libfrr.c:1213
16 0x0000564dea261b83 in main (argc=<optimized out>, argv=<optimized out>) at bgpd/bgp_main.c:505
```
With the configuration:
```
frr version 9.1-dev-MyOwnFRRVersion
frr defaults traditional
hostname ip-172-31-13-140
log file /tmp/debug.log
log syslog
service integrated-vtysh-config
!
debug bgp keepalives
debug bgp neighbor-events
debug bgp updates in
debug bgp updates out
!
router bgp 100
bgp router-id 9.9.9.9
no bgp ebgp-requires-policy
bgp bestpath aigp
neighbor 172.31.2.47 remote-as 200
!
address-family ipv4 unicast
neighbor 172.31.2.47 default-originate
neighbor 172.31.2.47 route-map RM_IN in
exit-address-family
exit
!
route-map RM_IN permit 10
set as-path prepend 200
exit
!
```
The issue is that we try to process NLRIs even if the attribute length is 0.
Later bgp_update() will handle route-maps and a crash occurs because all the
attributes are NULL, including aspath, where we dereference.
According to the RFC 4271:
A value of 0 indicates that neither the Network Layer
Reachability Information field nor the Path Attribute field is
present in this UPDATE message.
But with a fuzzed UPDATE message this can be faked. I think it's reasonable
to skip processing NLRIs if both update_len and attribute_len are 0.
Reported-by: Iggy Frankovic <iggyfran@amazon.com>
Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
(cherry picked from commit 28ccc24d38df1d51ed8a563507e5d6f6171fdd38)
diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c
index 60f1dcbcd..a02d54894 100644
--- a/bgpd/bgp_packet.c
+++ b/bgpd/bgp_packet.c
@@ -1983,7 +1983,7 @@ static int bgp_update_receive(struct peer *peer, bgp_size_t size)
/* Network Layer Reachability Information. */
update_len = end - stream_pnt(s);
- if (update_len) {
+ if (update_len && attribute_len) {
/* Set NLRI portion to structure. */
nlris[NLRI_UPDATE].afi = AFI_IP;
nlris[NLRI_UPDATE].safi = SAFI_UNICAST;
--
2.17.1

129
src/sonic-frr/patch/0025-bgpd-Use-treat-as-withdraw-for-tunnel-encapsulation-.patch Normal file
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@ -0,0 +1,129 @@
From 35b98f89f6a2ca5a79ed8893b4df612c0c6b4a37 Mon Sep 17 00:00:00 2001
From: Donatas Abraitis <donatas@opensourcerouting.org>
Date: Thu, 13 Jul 2023 22:32:03 +0300
Subject: [PATCH] bgpd: Use treat-as-withdraw for tunnel encapsulation
attribute
Before this path we used session reset method, which is discouraged by rfc7606.
Handle this as rfc requires.
Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
(cherry picked from commit bcb6b58d9530173df41d3a3cbc4c600ee0b4b186)
diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c
index 2ef50ffe5..ee20da332 100644
--- a/bgpd/bgp_attr.c
+++ b/bgpd/bgp_attr.c
@@ -1416,6 +1416,7 @@ bgp_attr_malformed(struct bgp_attr_parser_args *args, uint8_t subcode,
case BGP_ATTR_LARGE_COMMUNITIES:
case BGP_ATTR_ORIGINATOR_ID:
case BGP_ATTR_CLUSTER_LIST:
+ case BGP_ATTR_ENCAP:
case BGP_ATTR_OTC:
return BGP_ATTR_PARSE_WITHDRAW;
case BGP_ATTR_MP_REACH_NLRI:
@@ -2644,26 +2645,21 @@ ipv6_ext_community_ignore:
}
/* Parse Tunnel Encap attribute in an UPDATE */
-static int bgp_attr_encap(uint8_t type, struct peer *peer, /* IN */
- bgp_size_t length, /* IN: attr's length field */
- struct attr *attr, /* IN: caller already allocated */
- uint8_t flag, /* IN: attr's flags field */
- uint8_t *startp)
+static int bgp_attr_encap(struct bgp_attr_parser_args *args)
{
- bgp_size_t total;
uint16_t tunneltype = 0;
-
- total = length + (CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN) ? 4 : 3);
+ struct peer *const peer = args->peer;
+ struct attr *const attr = args->attr;
+ bgp_size_t length = args->length;
+ uint8_t type = args->type;
+ uint8_t flag = args->flags;
if (!CHECK_FLAG(flag, BGP_ATTR_FLAG_TRANS)
|| !CHECK_FLAG(flag, BGP_ATTR_FLAG_OPTIONAL)) {
- zlog_info(
- "Tunnel Encap attribute flag isn't optional and transitive %d",
- flag);
- bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR,
- BGP_NOTIFY_UPDATE_ATTR_FLAG_ERR,
- startp, total);
- return -1;
+ zlog_err("Tunnel Encap attribute flag isn't optional and transitive %d",
+ flag);
+ return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
+ args->total);
}
if (BGP_ATTR_ENCAP == type) {
@@ -2671,12 +2667,11 @@ static int bgp_attr_encap(uint8_t type, struct peer *peer, /* IN */
uint16_t tlv_length;
if (length < 4) {
- zlog_info(
+ zlog_err(
"Tunnel Encap attribute not long enough to contain outer T,L");
- bgp_notify_send_with_data(
- peer, BGP_NOTIFY_UPDATE_ERR,
- BGP_NOTIFY_UPDATE_OPT_ATTR_ERR, startp, total);
- return -1;
+ return bgp_attr_malformed(args,
+ BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
+ args->total);
}
tunneltype = stream_getw(BGP_INPUT(peer));
tlv_length = stream_getw(BGP_INPUT(peer));
@@ -2706,13 +2701,11 @@ static int bgp_attr_encap(uint8_t type, struct peer *peer, /* IN */
}
if (sublength > length) {
- zlog_info(
- "Tunnel Encap attribute sub-tlv length %d exceeds remaining length %d",
- sublength, length);
- bgp_notify_send_with_data(
- peer, BGP_NOTIFY_UPDATE_ERR,
- BGP_NOTIFY_UPDATE_OPT_ATTR_ERR, startp, total);
- return -1;
+ zlog_err("Tunnel Encap attribute sub-tlv length %d exceeds remaining length %d",
+ sublength, length);
+ return bgp_attr_malformed(args,
+ BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
+ args->total);
}
/* alloc and copy sub-tlv */
@@ -2760,13 +2753,10 @@ static int bgp_attr_encap(uint8_t type, struct peer *peer, /* IN */
if (length) {
/* spurious leftover data */
- zlog_info(
- "Tunnel Encap attribute length is bad: %d leftover octets",
- length);
- bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR,
- BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
- startp, total);
- return -1;
+ zlog_err("Tunnel Encap attribute length is bad: %d leftover octets",
+ length);
+ return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
+ args->total);
}
return 0;
@@ -3718,8 +3708,7 @@ enum bgp_attr_parse_ret bgp_attr_parse(struct peer *peer, struct attr *attr,
case BGP_ATTR_VNC:
#endif
case BGP_ATTR_ENCAP:
- ret = bgp_attr_encap(type, peer, length, attr, flag,
- startp);
+ ret = bgp_attr_encap(&attr_args);
break;
case BGP_ATTR_PREFIX_SID:
ret = bgp_attr_prefix_sid(&attr_args);
--
2.17.1

2
src/sonic-frr/patch/series
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@ -23,3 +23,5 @@ cross-compile-changes.patch
0021-zebra-remove-duplicated-nexthops-when-sending-fpm-msg.patch
0022-bgpd-Don-t-read-the-first-byte-of-ORF-header-if-we-a.patch
0023-bgpd-Make-sure-we-have-enough-data-to-read-two-bytes.patch
0024-bgpd-Do-not-process-NLRIs-if-the-attribute-length-is.patch
0025-bgpd-Use-treat-as-withdraw-for-tunnel-encapsulation-.patch