RE: [PATCH] net: ethernet: renesas: rswitch: fix device_node refcount leak in rswitch_get_port_node()

Hello Manush,

I am sorry I missed the difference between ports and port.

Please disregard my last message. 

Best regards,

Michael

Reviewed-by: Michael Dege <[email protected]>

> -----Original Message-----
> From: Michael Dege
> Sent: Thursday, August 13, 2026 2:45 PM
> To: Manush Prajwal <[email protected]>; Yoshihiro Shimoda <[email protected]>
> Cc: [email protected]; [email protected]
> Subject: RE: [PATCH] net: ethernet: renesas: rswitch: fix device_node refcount leak in
> rswitch_get_port_node()
> 
> Hello Manush,
> 
> Thank you for your patch.
> 
> > -----Original Message-----
> > From: Manush Prajwal <[email protected]>
> > Sent: Thursday, August 13, 2026 1:11 PM
> > To: Yoshihiro Shimoda <[email protected]>
> > Cc: [email protected]; [email protected]; Manush
> > Prajwal <[email protected]>
> > Subject: [PATCH] net: ethernet: renesas: rswitch: fix device_node
> > refcount leak in
> > rswitch_get_port_node()
> >
> > [You don't often get email from [email protected]. Learn why
> > this is important at https://aka.ms/LearnAboutSenderIdentification ]
> >
> > On an of_property_read_u32() failure, rswitch_get_port_node() sets
> > port to NULL and jumps to the out label before releasing the reference
> > the for_each_available_child_of_node() iterator was holding on it.
> > Once port is overwritten with NULL, that reference can never be
> > released since out: only puts "ports", the parent node. Call
> > of_node_put(port) before clearing it.
> >
> > Signed-off-by: Manush Prajwal <[email protected]>
> > ---
> >  drivers/net/ethernet/renesas/rswitch_main.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/net/ethernet/renesas/rswitch_main.c
> > b/drivers/net/ethernet/renesas/rswitch_main.c
> > index 6fe9648163..ffdc42f430 100644
> > --- a/drivers/net/ethernet/renesas/rswitch_main.c
> > +++ b/drivers/net/ethernet/renesas/rswitch_main.c
> > @@ -1315,6 +1315,7 @@ static struct device_node *rswitch_get_port_node(struct rswitch_device *rdev)
> >         for_each_available_child_of_node(ports, port) {
> >                 err = of_property_read_u32(port, "reg", &index);
> >                 if (err < 0) {
> > +                       of_node_put(port);
> 
> I am not sure why you are adding this here. The code jumps to the label "out" and that is where
> "of_node_put(port)" is called. Is there a reason why you want to call this twice in a row?
> 
> Best regards,
> 
> Michael
> 
> 
> >                         port = NULL;
> >                         goto out;
> >                 }
> > --
> > 2.46.2.windows.1
> >