[PATCH] teamd: do not process lacpdu before the port ifinfo is set

[Xin Long]

Now the port ifinfo will be set in obj_input_newlink when a RTM_NEWLINK
event is received.

But when a port is being added, if a lacpdu gets received on this port
before the RTM_NEWLINK event, lacpdu_recv will process the packet with
incorrect port ifinfo.

In Patrick's case, as ifinfo->master_ifindex was 0, it would skip this
port in teamd_for_each_tdport, which caused lacp_port->agg_lead not to
be updated in lacp_switch_agg_lead. Later the lacp_port actor would go
to a unexpected state.

This patch is to avoid it by checking teamd_port_present in lacpdu_recv
so that it would not process lacpdu before the port ifinfo is set.

Reported-by: Patrick Talbert 
Tested-by: Patrick Talbert 
Signed-off-by: Xin Long 
---
 teamd/teamd_runner_lacp.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/teamd/teamd_runner_lacp.c b/teamd/teamd_runner_lacp.c
index 5601278..1310f67 100644
--- a/teamd/teamd_runner_lacp.c
+++ b/teamd/teamd_runner_lacp.c
@@ -1075,6 +1075,9 @@ static int lacpdu_recv(struct lacp_port *lacp_port)
    if (err <= 0)
    	return err;

+	if (!teamd_port_present(lacp_port->ctx, lacp_port->tdport))
+		return 0;
+
    if (!lacpdu_check(&lacpdu)) {
    	teamd_log_warn("malformed LACP PDU came.");
    	return 0;

[Jiri Pirko]

Wed, Oct 11, 2017 at 08:17:38AM CEST, [e-mail] wrote:
> Now the port ifinfo will be set in obj_input_newlink when a RTM_NEWLINK
> event is received.
>
> But when a port is being added, if a lacpdu gets received on this port
> before the RTM_NEWLINK event, lacpdu_recv will process the packet with
> incorrect port ifinfo.
>
> In Patrick's case, as ifinfo->master_ifindex was 0, it would skip this
> port in teamd_for_each_tdport, which caused lacp_port->agg_lead not to
> be updated in lacp_switch_agg_lead. Later the lacp_port actor would go
> to a unexpected state.
>
> This patch is to avoid it by checking teamd_port_present in lacpdu_recv
> so that it would not process lacpdu before the port ifinfo is set.
>
> Reported-by: Patrick Talbert 
> Tested-by: Patrick Talbert 
> Signed-off-by: Xin Long

applied, thanks!