From: Vlad Yasevich Date: Fri, 7 Sep 2007 15:47:45 +0000 (-0400) Subject: SCTP: Explicitely discard OOTB chunks X-Git-Tag: v2.6.23-rc9~41^2~4 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=d3f259687fd248aa4de477149481478c122ba48b;p=linux-2.6-omap-h63xx.git SCTP: Explicitely discard OOTB chunks Explicitely discard OOTB chunks, whether the result is a SHUTDOWN COMPLETE or an ABORT. We need to discard the OOTB SHUTDOWN ACK to prevent bombing attackes since responsed MUST NOT be bundled. We also explicietely discard in the ABORT case since that function is widely used internally. Signed-off-by: Vlad Yasevich Acked-by: Neil Horman --- diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 385f1757158..5e7fb0f54b8 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -2965,6 +2965,7 @@ sctp_disposition_t sctp_sf_tabort_8_4_8(const struct sctp_endpoint *ep, SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); + sctp_sf_pdiscard(ep, asoc, type, arg, commands); return SCTP_DISPOSITION_CONSUME; } @@ -3148,11 +3149,9 @@ sctp_disposition_t sctp_sf_ootb(const struct sctp_endpoint *ep, } while (ch_end < skb_tail_pointer(skb)); if (ootb_shut_ack) - sctp_sf_shut_8_4_5(ep, asoc, type, arg, commands); + return sctp_sf_shut_8_4_5(ep, asoc, type, arg, commands); else - sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); - - return sctp_sf_pdiscard(ep, asoc, type, arg, commands); + return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); } /* @@ -3218,7 +3217,11 @@ static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep, if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) return sctp_sf_pdiscard(ep, asoc, type, arg, commands); - return SCTP_DISPOSITION_CONSUME; + /* We need to discard the rest of the packet to prevent + * potential bomming attacks from additional bundled chunks. + * This is documented in SCTP Threats ID. + */ + return sctp_sf_pdiscard(ep, asoc, type, arg, commands); } return SCTP_DISPOSITION_NOMEM;