An issue was discovered in Open vSwitch (OvS) 2.7.x through 2.7.6, affecting ofproto_rule_insert__ in ofproto/ofproto.c. During bundle commit, flows that are added in a bundle are applied to ofproto in order. If a flow cannot be added (e.g., the flow action is a go-to for a group id that does not exist), OvS tries to revert back all previous flows that were successfully applied from the same bundle. This is possible since OvS maintains list of old flows that were replaced by flows from the bundle. While reinserting old flows, OvS has an assertion failure due to a check on rule state != RULE_INITIALIZED. This would work for new flows, but for an old flow the rule state is RULE_REMOVED. The assertion failure causes an OvS crash.
The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.
| Link | Tags |
|---|---|
| https://access.redhat.com/errata/RHSA-2019:0053 | third party advisory vendor advisory |
| https://usn.ubuntu.com/3873-1/ | third party advisory vendor advisory |
| https://access.redhat.com/errata/RHSA-2018:3500 | third party advisory vendor advisory |
| https://github.com/openvswitch/ovs/commit/0befd1f3745055c32940f5faf9559be6a14395e6 | exploit third party advisory patch |
| https://access.redhat.com/errata/RHSA-2019:0081 | third party advisory vendor advisory |