Subject: Re: [PATCH] net: qrtr: Fix port ID for control messages

From: Bjorn Andersson <[email-masked]>
Date: Thu, 24 Sep 2020 09:25:59 -0500

On Thu 24 Sep 04:53 CDT 2020, Loic Poulain wrote:

> The port ID for control messages was uncorrectly set with broadcast
> node ID value, causing message to be dropped on remote side since
> not passing packet filtering (cb->dst_port != QRTR_PORT_CTRL).
> 

This does indeed make more sense. Unfortunately after reading the
documentation a few times I do believe that it doesn't actually specify
the expected port (only the node id) - and that the recipient shall
ignore "the field"...

Chris, can you please let us know what the actual expectation of the
modem is? (SDX55 in this case, but Arun must have tested this on
something with more lax expectations?)

Regards,
Bjorn

> Fixes: d27e77a3de28 ("net: qrtr: Reset the node and port ID of broadcast messages")
> Signed-off-by: Loic Poulain <[email-masked]>
> ---
>  net/qrtr/qrtr.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c
> index b4c0db0..e09154b 100644
> --- a/net/qrtr/qrtr.c
> +++ b/net/qrtr/qrtr.c
> @@ -348,7 +348,7 @@ static int qrtr_node_enqueue(struct qrtr_node *node, struct sk_buff *skb,
>  	hdr->src_port_id = cpu_to_le32(from->sq_port);
>  	if (to->sq_port == QRTR_PORT_CTRL) {
>  		hdr->dst_node_id = cpu_to_le32(node->nid);
> -		hdr->dst_port_id = cpu_to_le32(QRTR_NODE_BCAST);
> +		hdr->dst_port_id = cpu_to_le32(QRTR_PORT_CTRL);
>  	} else {
>  		hdr->dst_node_id = cpu_to_le32(to->sq_node);
>  		hdr->dst_port_id = cpu_to_le32(to->sq_port);
> -- 
> 2.7.4
>