From 21fe5db0c9a8e92bbfce42da89ce20b826216fa1 Mon Sep 17 00:00:00 2001 From: Jesse Gross <jesse@nicira.com> Date: Thu, 8 Sep 2011 15:32:24 -0700 Subject: [PATCH] datapath: Calculate flow hash after extracting metadata. When we execute a packet from userspace we first extract the header fields from the packet and then add supplied metadata. However, we compute the hash of the packet in between these two steps despite the fact that the metadata can affect the hash. This can lead to two separate hashes for packets of the same flow. Found by code inspection, not an actual real-world problem. Signed-off-by: Jesse Gross <jesse@nicira.com> Acked-by: Ben Pfaff <blp@nicira.com> --- datapath/datapath.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/datapath/datapath.c b/datapath/datapath.c index a964c27f4..2f30bdcf8 100644 --- a/datapath/datapath.c +++ b/datapath/datapath.c @@ -691,7 +691,6 @@ static int odp_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) err = flow_extract(packet, -1, &flow->key, &key_len, &is_frag); if (err) goto err_flow_put; - flow->tbl_node.hash = flow_hash(&flow->key, key_len); err = flow_metadata_from_nlattrs(&flow->key.eth.in_port, &flow->key.eth.tun_id, @@ -699,6 +698,8 @@ static int odp_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) if (err) goto err_flow_put; + flow->tbl_node.hash = flow_hash(&flow->key, key_len); + acts = flow_actions_alloc(a[ODP_PACKET_ATTR_ACTIONS]); err = PTR_ERR(acts); if (IS_ERR(acts)) -- 2.47.0