Today in OVS, when errors are encountered during the execution of an action the entire batch of packets may be deleted (for e.g. in processing push_tnl_action, if the port is not found in the port_cache of PMD). The remaining actions continue to be executed even though there are no packets to be processed.
It is assumed that the code dealing with each action checks that the batch is not empty before executing. Crashes may occur if the assumption is not met. The patch makes OVS skip processing of further actions from the action-set once a batch is emptied. Doing so centralizes the check in one place and avoids the possibility of crashes. This change DOES NOT fix any existing bug in the code, only a precautionary measure to avoid crashes if new actions does not take care of empty batches. Signed-off-by: Vishal Deep Ajmera <[email protected]> --- lib/odp-execute.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/lib/odp-execute.c b/lib/odp-execute.c index 2d20cd5..1090fa8 100644 --- a/lib/odp-execute.c +++ b/lib/odp-execute.c @@ -686,9 +686,12 @@ odp_execute_actions(void *dp, struct dp_packet_batch *batch, bool steal, dp_execute_action(dp, batch, a, may_steal); - if (last_action) { - /* We do not need to free the packets. dp_execute_actions() - * has stolen them */ + if (last_action || batch->count == 0) { + /* We do not need to free the packets. + * Either dp_execute_actions() has stolen them + * or the batch is freed due to errors. In either + * case we do not need to execute further actions. + */ return; } } -- 1.9.1 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
