Ovs ko passes odp key and packet to userspace. Next packet is extracted into flow, which is the input for xlate to generate wc. At last, ukey(= odp_key/wc) is installed into datapath. If the odp_key is not consistant with packet extracted flow. The ukey will be wrong.
commit [1] was created to fix inconsistance caused by bad tcp header. commit [2] was cretaed to fix inconsistance caused by bad ip header. There is no guarantee of the consistance of odp_key and packet flow. So it is necessary to make the check to prevent from installing wrong ukey. [1] 1f5749c790accd98dbcafdaefc40bf5e52d7c672 [2] 79349cbab0b2a755140eedb91833ad2760520a83 Signed-off-by: Cheng Li <[email protected]> --- ofproto/ofproto-dpif-upcall.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/ofproto/ofproto-dpif-upcall.c b/ofproto/ofproto-dpif-upcall.c index b5cbeed87..6e46e5a5a 100644 --- a/ofproto/ofproto-dpif-upcall.c +++ b/ofproto/ofproto-dpif-upcall.c @@ -66,6 +66,7 @@ COVERAGE_DEFINE(upcall_flow_limit_reduced); COVERAGE_DEFINE(upcall_flow_limit_scaled); COVERAGE_DEFINE(upcall_ukey_contention); COVERAGE_DEFINE(upcall_ukey_replace); +COVERAGE_DEFINE(upcall_packet_flow_inconsistant); /* A thread that reads upcalls from dpif, forwards each upcall's packet, * and possibly sets up a kernel flow as a cache. */ @@ -840,6 +841,8 @@ recv_upcalls(struct handler *handler) struct dpif_upcall dupcalls[UPCALL_MAX_BATCH]; struct upcall upcalls[UPCALL_MAX_BATCH]; struct flow flows[UPCALL_MAX_BATCH]; + struct flow odp_flow; + struct flow_wildcards flow_wc; size_t n_upcalls, i; n_upcalls = 0; @@ -903,8 +906,17 @@ recv_upcalls(struct handler *handler) upcall->out_tun_key = dupcall->out_tun_key; upcall->actions = dupcall->actions; + /* Save odp flow before overwrite. */ + memcpy(&odp_flow, flow, sizeof flow); pkt_metadata_from_flow(&dupcall->packet.md, flow); flow_extract(&dupcall->packet, flow); + flow_wildcards_init_for_packet(&flow_wc, &flow); + if (!flow_equal_except(&odp_flow, flow, &flow_wc)) { + /* If odp flow is not consistant with flow extract from packet, + * bad ukey/mask will be installed. */ + COVERAGE_INC(upcall_packet_flow_inconsistant); + goto cleanup; + } error = process_upcall(udpif, upcall, &upcall->odp_actions, &upcall->wc); -- 2.39.3 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
