Re: [PATCH v2 net-next 8/9] openvswitch: Add force commit.
From: Joe Stringer <hidden>
Date: 2017-02-08 23:54:13
On 8 February 2017 at 11:32, Jarno Rajahalme [off-list ref] wrote:
Stateful network admission policy may allow connections to one direction and reject connections initiated in the other direction. After policy change it is possible that for a new connection an overlapping conntrack entry already exists, where the original direction of the existing connection is opposed to the new connection's initial packet. Most importantly, conntrack state relating to the current packet gets the "reply" designation based on whether the original direction tuple or the reply direction tuple matched. If this "directionality" is wrong w.r.t. to the stateful network admission policy it may happen that packets in neither direction are correctly admitted. This patch adds a new "force commit" option to the OVS conntrack action that checks the original direction of an existing conntrack entry. If that direction is opposed to the current packet, the existing conntrack entry is deleted and a new one is subsequently created in the correct direction. Signed-off-by: Jarno Rajahalme <redacted>
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quoted hunk ↗ jump to hunk
if (help && rcu_access_pointer(help->helper) != info->helper) return false; } + /* Force conntrack entry direction to the current packet? */ + if (info->force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { + /* Delete the conntrack entry if confirmed, else just release + * the reference. + */ + if (nf_ct_is_confirmed(ct)) + nf_ct_delete(ct, 0, 0); + else + nf_conntrack_put(&ct->ct_general); + skb->nfct = NULL; + skb->nfctinfo = 0;
This can use nf_ct_set().