diff options
| author | Avneesh Sachdev <avneesh@opensourcerouting.org> | 2012-05-05 23:50:30 -0700 |
|---|---|---|
| committer | David Lamparter <equinox@opensourcerouting.org> | 2012-10-25 10:15:59 -0700 |
| commit | a22ab5a560c7a46f6ecc6feb874c0dbbde9699c6 (patch) | |
| tree | 0f2eb80dc14b21ef14e0de45e1f32d581c7186c0 | |
| parent | 4effc29fb1c33a87a8d386de39c20d36a6956645 (diff) | |
isisd: tighten checks on ISIS pdu length
* isisd/isis_pdu.c: Fix problem where isisd would crash if it
received a LAN IIH with the 'pdu length' field set to zero.
Similar problems can occur in parsing other ISIS PDUs as well --
check that the PDU length in an ISIS hello, LSP or SNP packet is
at least as big as the size of the respective fixed header.
| -rw-r--r-- | isisd/isis_pdu.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/isisd/isis_pdu.c b/isisd/isis_pdu.c index 497fad20..7375a3eb 100644 --- a/isisd/isis_pdu.c +++ b/isisd/isis_pdu.c @@ -442,7 +442,8 @@ process_p2p_hello (struct isis_circuit *circuit) hdr = (struct isis_p2p_hello_hdr *) STREAM_PNT (circuit->rcv_stream); pdu_len = ntohs (hdr->pdu_len); - if (pdu_len > ISO_MTU(circuit) || + if (pdu_len < (ISIS_FIXED_HDR_LEN + ISIS_P2PHELLO_HDRLEN) || + pdu_len > ISO_MTU(circuit) || pdu_len > stream_get_endp (circuit->rcv_stream)) { zlog_warn ("ISIS-Adj (%s): Rcvd P2P IIH from (%s) with " @@ -909,7 +910,8 @@ process_lan_hello (int level, struct isis_circuit *circuit, u_char * ssnpa) hdr.prio = stream_getc (circuit->rcv_stream); stream_get (hdr.lan_id, circuit->rcv_stream, ISIS_SYS_ID_LEN + 1); - if (hdr.pdu_len > ISO_MTU(circuit) || + if (hdr.pdu_len < (ISIS_FIXED_HDR_LEN + ISIS_LANHELLO_HDRLEN) || + hdr.pdu_len > ISO_MTU(circuit) || hdr.pdu_len > stream_get_endp (circuit->rcv_stream)) { zlog_warn ("ISIS-Adj (%s): Rcvd LAN IIH from (%s) with " @@ -1202,7 +1204,7 @@ process_lsp (int level, struct isis_circuit *circuit, u_char * ssnpa) pdu_len = ntohs (hdr->pdu_len); /* lsp length check */ - if (pdu_len < ISIS_LSP_HDR_LEN || + if (pdu_len < (ISIS_FIXED_HDR_LEN + ISIS_LSP_HDR_LEN) || pdu_len > ISO_MTU(circuit) || pdu_len > stream_get_endp (circuit->rcv_stream)) { @@ -1545,7 +1547,7 @@ process_snp (int snp_type, int level, struct isis_circuit *circuit, (struct isis_complete_seqnum_hdr *) STREAM_PNT (circuit->rcv_stream); stream_forward_getp (circuit->rcv_stream, ISIS_CSNP_HDRLEN); pdu_len = ntohs (chdr->pdu_len); - if (pdu_len < ISIS_CSNP_HDRLEN || + if (pdu_len < (ISIS_FIXED_HDR_LEN + ISIS_CSNP_HDRLEN) || pdu_len > ISO_MTU(circuit) || pdu_len > stream_get_endp (circuit->rcv_stream)) { @@ -1560,7 +1562,7 @@ process_snp (int snp_type, int level, struct isis_circuit *circuit, (struct isis_partial_seqnum_hdr *) STREAM_PNT (circuit->rcv_stream); stream_forward_getp (circuit->rcv_stream, ISIS_PSNP_HDRLEN); pdu_len = ntohs (phdr->pdu_len); - if (pdu_len < ISIS_PSNP_HDRLEN || + if (pdu_len < (ISIS_FIXED_HDR_LEN + ISIS_PSNP_HDRLEN) || pdu_len > ISO_MTU(circuit) || pdu_len > stream_get_endp (circuit->rcv_stream)) { |