diff options
Diffstat (limited to 'meta-networking/recipes-protocols/quagga/files/0001-ospfd-CVE-2013-2236-stack-overrun-in-apiserver.patch')
-rw-r--r-- | meta-networking/recipes-protocols/quagga/files/0001-ospfd-CVE-2013-2236-stack-overrun-in-apiserver.patch | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/meta-networking/recipes-protocols/quagga/files/0001-ospfd-CVE-2013-2236-stack-overrun-in-apiserver.patch b/meta-networking/recipes-protocols/quagga/files/0001-ospfd-CVE-2013-2236-stack-overrun-in-apiserver.patch new file mode 100644 index 0000000000..30b05c262f --- /dev/null +++ b/meta-networking/recipes-protocols/quagga/files/0001-ospfd-CVE-2013-2236-stack-overrun-in-apiserver.patch @@ -0,0 +1,106 @@ +Subject: [PATCH] ospfd: CVE-2013-2236, stack overrun in apiserver + +Upstream-Status: Backport + +the OSPF API-server (exporting the LSDB and allowing announcement of +Opaque-LSAs) writes past the end of fixed on-stack buffers. This leads +to an exploitable stack overflow. + +For this condition to occur, the following two conditions must be true: +- Quagga is configured with --enable-opaque-lsa +- ospfd is started with the "-a" command line option + +If either of these does not hold, the relevant code is not executed and +the issue does not get triggered. + +Since the issue occurs on receiving large LSAs (larger than 1488 bytes), +it is possible for this to happen during normal operation of a network. +In particular, if there is an OSPF router with a large number of +interfaces, the Router-LSA of that router may exceed 1488 bytes and +trigger this, leading to an ospfd crash. + +For an attacker to exploit this, s/he must be able to inject valid LSAs +into the OSPF domain. Any best-practice protection measure (using +crypto authentication, restricting OSPF to internal interfaces, packet +filtering protocol 89, etc.) will prevent exploitation. On top of that, +remote (not on an OSPF-speaking network segment) attackers will have +difficulties bringing up the adjacency needed to inject a LSA. + +This patch only performs minimal changes to remove the possibility of a +stack overrun. The OSPF API in general is quite ugly and needs a +rewrite. + +Reported-by: Ricky Charlet <ricky.charlet@hp.com> +Cc: Florian Weimer <fweimer@redhat.com> +Signed-off-by: David Lamparter <equinox@opensourcerouting.org> +--- + ospfd/ospf_api.c | 25 ++++++++++++++++++------- + 1 files changed, 18 insertions(+), 7 deletions(-) + +diff --git a/ospfd/ospf_api.c b/ospfd/ospf_api.c +index 74a49e3..fae942e 100644 +--- a/ospfd/ospf_api.c ++++ b/ospfd/ospf_api.c +@@ -472,6 +472,9 @@ new_msg_register_event (u_int32_t seqnum, struct lsa_filter_type *filter) + emsg->filter.typemask = htons (filter->typemask); + emsg->filter.origin = filter->origin; + emsg->filter.num_areas = filter->num_areas; ++ if (len > sizeof (buf)) ++ len = sizeof(buf); ++ /* API broken - missing memcpy to fill data */ + return msg_new (MSG_REGISTER_EVENT, emsg, seqnum, len); + } + +@@ -488,6 +491,9 @@ new_msg_sync_lsdb (u_int32_t seqnum, struct lsa_filter_type *filter) + smsg->filter.typemask = htons (filter->typemask); + smsg->filter.origin = filter->origin; + smsg->filter.num_areas = filter->num_areas; ++ if (len > sizeof (buf)) ++ len = sizeof(buf); ++ /* API broken - missing memcpy to fill data */ + return msg_new (MSG_SYNC_LSDB, smsg, seqnum, len); + } + +@@ -501,13 +507,15 @@ new_msg_originate_request (u_int32_t seqnum, + int omsglen; + char buf[OSPF_API_MAX_MSG_SIZE]; + +- omsglen = sizeof (struct msg_originate_request) - sizeof (struct lsa_header) +- + ntohs (data->length); +- + omsg = (struct msg_originate_request *) buf; + omsg->ifaddr = ifaddr; + omsg->area_id = area_id; +- memcpy (&omsg->data, data, ntohs (data->length)); ++ ++ omsglen = ntohs (data->length); ++ if (omsglen > sizeof (buf) - offsetof (struct msg_originate_request, data)) ++ omsglen = sizeof (buf) - offsetof (struct msg_originate_request, data); ++ memcpy (&omsg->data, data, omsglen); ++ omsglen += sizeof (struct msg_originate_request) - sizeof (struct lsa_header); + + return msg_new (MSG_ORIGINATE_REQUEST, omsg, seqnum, omsglen); + } +@@ -627,13 +635,16 @@ new_msg_lsa_change_notify (u_char msgtype, + assert (data); + + nmsg = (struct msg_lsa_change_notify *) buf; +- len = ntohs (data->length) + sizeof (struct msg_lsa_change_notify) +- - sizeof (struct lsa_header); + nmsg->ifaddr = ifaddr; + nmsg->area_id = area_id; + nmsg->is_self_originated = is_self_originated; + memset (&nmsg->pad, 0, sizeof (nmsg->pad)); +- memcpy (&nmsg->data, data, ntohs (data->length)); ++ ++ len = ntohs (data->length); ++ if (len > sizeof (buf) - offsetof (struct msg_lsa_change_notify, data)) ++ len = sizeof (buf) - offsetof (struct msg_lsa_change_notify, data); ++ memcpy (&nmsg->data, data, len); ++ len += sizeof (struct msg_lsa_change_notify) - sizeof (struct lsa_header); + + return msg_new (msgtype, nmsg, seqnum, len); + } +-- +1.7.5.4 + |