Re: [patch net-next] devlink: don't allow to change net namespace for FW_ACTIVATE reload action

[Simon Horman <simon.horman@corigine.com>]

On Fri, Feb 10, 2023 at 11:43:04AM -0800, Jacob Keller wrote:
> 
> 
> On 2/10/2023 5:15 AM, Simon Horman wrote:
> > On Fri, Feb 10, 2023 at 12:58:27PM +0100, Jiri Pirko wrote:
> >> From: Jiri Pirko <jiri@nvidia.com>
> >>
> >> The change on network namespace only makes sense during re-init reload
> >> action. For FW activation it is not applicable. So check if user passed
> >> an ATTR indicating network namespace change request and forbid it.
> >>
> >> Fixes: ccdf07219da6 ("devlink: Add reload action option to devlink reload command")
> >> Signed-off-by: Jiri Pirko <jiri@nvidia.com>
> >> ---
> >> Sending to net-next as this is not actually fixing any real bug,
> >> it just adds a forgotten check.
> >> ---
> >>  net/devlink/dev.c | 5 +++++
> >>  1 file changed, 5 insertions(+)
> >>
> >> diff --git a/net/devlink/dev.c b/net/devlink/dev.c
> >> index 78d824eda5ec..a6a2bcded723 100644
> >> --- a/net/devlink/dev.c
> >> +++ b/net/devlink/dev.c
> >> @@ -474,6 +474,11 @@ int devlink_nl_cmd_reload(struct sk_buff *skb, struct genl_info *info)
> >>  	if (info->attrs[DEVLINK_ATTR_NETNS_PID] ||
> >>  	    info->attrs[DEVLINK_ATTR_NETNS_FD] ||
> >>  	    info->attrs[DEVLINK_ATTR_NETNS_ID]) {
> >> +		if (action != DEVLINK_RELOAD_ACTION_DRIVER_REINIT) {
> >> +			NL_SET_ERR_MSG_MOD(info->extack,
> >> +					   "Changing namespace is only supported for reinit action");
> >> +			return -EOPNOTSUPP;
> >> +		}
> > 
> > Is this also applicable in the case where the requested ns (dest_net)
> > is the same as the current ns, which I think means that the ns
> > is not changed?
> > 
> 
> In that case wouldn't userspace simply not add the attribute though?

Yes, that may be the case.
But my question is about the correct behaviour if user space doesn't do that.