From f316975cedd8ef17d47b56be0d3d21711fe44a25 Mon Sep 17 00:00:00 2001 From: Donald Sharp Date: Wed, 2 Nov 2022 13:24:48 -0400 Subject: [PATCH] bgpd: Ensure that bgp open message stream has enough data to read If a operator receives an invalid packet that is of insufficient size then it is possible for BGP to assert during reading of the packet instead of gracefully resetting the connection with the peer. Signed-off-by: Donald Sharp (cherry picked from commit 766eec1b7accffe2c04a5c9ebb14e9f487bb9f78) CVE: CVE-2022-43681 Upstream-Status: Backport [https://github.com/FRRouting/frr/commit/766eec1b7accffe2c04a5c9ebb14e9f487bb9f78] Signed-off-by: Jonas Gorski --- bgpd/bgp_packet.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c index bcd47e32d453..5225db29fe09 100644 --- a/bgpd/bgp_packet.c +++ b/bgpd/bgp_packet.c @@ -1176,8 +1176,27 @@ static int bgp_open_receive(struct peer *peer, bgp_size_t size) || CHECK_FLAG(peer->flags, PEER_FLAG_EXTENDED_OPT_PARAMS)) { uint8_t opttype; + if (STREAM_READABLE(peer->curr) < 1) { + flog_err( + EC_BGP_PKT_OPEN, + "%s: stream does not have enough bytes for extended optional parameters", + peer->host); + bgp_notify_send(peer, BGP_NOTIFY_OPEN_ERR, + BGP_NOTIFY_OPEN_MALFORMED_ATTR); + return BGP_Stop; + } + opttype = stream_getc(peer->curr); if (opttype == BGP_OPEN_NON_EXT_OPT_TYPE_EXTENDED_LENGTH) { + if (STREAM_READABLE(peer->curr) < 2) { + flog_err( + EC_BGP_PKT_OPEN, + "%s: stream does not have enough bytes to read the extended optional parameters optlen", + peer->host); + bgp_notify_send(peer, BGP_NOTIFY_OPEN_ERR, + BGP_NOTIFY_OPEN_MALFORMED_ATTR); + return BGP_Stop; + } optlen = stream_getw(peer->curr); SET_FLAG(peer->sflags, PEER_STATUS_EXT_OPT_PARAMS_LENGTH); -- 2.40.1