diff options
| author | Donatas Abraitis <donatas@opensourcerouting.org> | 2023-10-20 17:49:18 +0300 |
|---|---|---|
| committer | Mergify <37929162+mergify[bot]@users.noreply.github.com> | 2023-10-25 11:23:34 +0000 |
| commit | d19727b4ac595f17da530f5fa0bbd3bb16ea2aa1 (patch) | |
| tree | 997f283a9feb0bda5ea483e0c3c2509fbeb63d54 | |
| parent | 8d04bac524c65952ecc84924e3dc16d1881561a2 (diff) | |
bgpd: Handle MP_REACH_NLRI malformed packets with session reset
Avoid crashing bgpd.
```
(gdb)
bgp_mp_reach_parse (args=<optimized out>, 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 <iggyfran@amazon.com>
Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
(cherry picked from commit b08afc81c60607a4f736f418f2e3eb06087f1a35)
| -rw-r--r-- | bgpd/bgp_attr.c | 6 | ||||
| -rw-r--r-- | bgpd/bgp_attr.h | 1 | ||||
| -rw-r--r-- | bgpd/bgp_packet.c | 6 |
3 files changed, 2 insertions, 11 deletions
diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c index 60e41ac1cc..bc519a4816 100644 --- a/bgpd/bgp_attr.c +++ b/bgpd/bgp_attr.c @@ -2388,7 +2388,7 @@ 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; @@ -3658,10 +3658,6 @@ 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 1c7e88a4f9..3db0863d3b 100644 --- a/bgpd/bgp_attr.h +++ b/bgpd/bgp_attr.h @@ -364,7 +364,6 @@ 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 ec692277b2..f88e1e5afc 100644 --- a/bgpd/bgp_packet.c +++ b/bgpd/bgp_packet.c @@ -2053,8 +2053,7 @@ 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; @@ -2075,9 +2074,6 @@ 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]) { |