Re: [PATCH V9 net-next 11/11] net: add ndo_validate_addr check in dev_set_mac_address

[Jijie Shao]

on 2024/9/10 16:39, Kalesh Anakkur Purayil wrote:
> On Tue, Sep 10, 2024 at 1:36 PM Jijie Shao <shaojijie@xxxxxxxxxx> wrote:
> > If driver implements ndo_validate_addr,
> > core should check the mac address before ndo_set_mac_address.
> >
> > Signed-off-by: Jijie Shao <shaojijie@xxxxxxxxxx>
> > Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
> > ---
> > ChangeLog:
> > v2 -> v3:
> >    - Use ndo_validate_addr() instead of is_valid_ether_addr()
> >      in dev_set_mac_address(), suggested by Jakub and Andrew.
> >    v2: https://lore.kernel.org/all/20240820140154.137876-1-shaojijie@xxxxxxxxxx/
> > ---
> >   net/core/dev.c | 5 +++++
> >   1 file changed, 5 insertions(+)
> >
> > diff --git a/net/core/dev.c b/net/core/dev.c
> > index 22c3f14d9287..00e0f473ed44 100644
> > --- a/net/core/dev.c
> > +++ b/net/core/dev.c
> > @@ -9087,6 +9087,11 @@ int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa,
> >                  return -EOPNOTSUPP;
> >          if (sa->sa_family != dev->type)
> >                  return -EINVAL;
> > +       if (ops->ndo_validate_addr) {
> > +               err = ops->ndo_validate_addr(dev);
> > +               if (err)
> > +                       return err;
> > +       }

This patch may not work as expected.

ndo_validate_addr() has only one parameter.
The sa parameter of the MAC address is not transferred to the function.
So ndo_validate_addr() checks the old MAC address, not the new MAC address.

I haven't found a better way to fix it yet.
This patch may be dropped in v10.

Sorry,
	Jijie Shao