Re: [PATCH v2 7/9] net: stmmac: dwmac-sun8i: fix OF child-node lookup

[Johan Hovold]

On Thu, Sep 06, 2018 at 10:03:37PM +0200, Corentin Labbe wrote:
> On Mon, Aug 27, 2018 at 10:21:51AM +0200, Johan Hovold wrote:
> > Use the new of_get_compatible_child() helper to lookup the mdio-internal
> > child node instead of using of_find_compatible_node(), which searches
> > the entire tree from a given start node and thus can return an unrelated
> > (i.e. non-child) node.
> > 
> > This also addresses a potential use-after-free (e.g. after probe
> > deferral) as the tree-wide helper drops a reference to its first
> > argument (i.e. the mdio-mux node). Fortunately, this was inadvertently
> > balanced by a failure to drop the mdio-mux reference after lookup.
> > 
> > While at it, also fix the related mdio-internal- and phy-node reference
> > leaks.
> > 
> > Fixes: 634db83b8265 ("net: stmmac: dwmac-sun8i: Handle integrated/external MDIOs")
> > Cc: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>
> > Cc: Andrew Lunn <andrew@xxxxxxx>
> > Cc: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx>
> > Cc: Alexandre Torgue <alexandre.torgue@xxxxxx>
> > Cc: Jose Abreu <joabreu@xxxxxxxxxxxx>
> > Cc: David S. Miller <davem@xxxxxxxxxxxxx>
> > Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>

> Tested-by: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>

Thanks for testing.

Johan