Re: [PATCH] can: vxcan: Fix memleak in vxcan_newlink

[Oliver Hartkopp]

On 22.10.20 18:14, Jakub Kicinski wrote:
> On Wed, 21 Oct 2020 13:20:16 +0200 Oliver Hartkopp wrote:
> > On 21.10.20 07:21, Dinghao Liu wrote:
> > > When rtnl_configure_link() fails, peer needs to be
> > > freed just like when register_netdevice() fails.
> > >
> > > Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
> >
> > Acked-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
> >
> > Btw. as the vxcan.c driver bases on veth.c the same issue can be found
> > there!
> >
> > At this point:
> > https://elixir.bootlin.com/linux/latest/source/drivers/net/veth.c#L1398
> >
> > err_register_dev:
> >           /* nothing to do */
> > err_configure_peer:
> >           unregister_netdevice(peer);
> >           return err; <<<<<<<<<<<<<<<<<<<<<<<
> >
> > err_register_peer:
> >           free_netdev(peer);
> >           return err;
> > }
> >
> > IMO the return must be removed to fall through the next label and free
> > the netdevice too.
> >
> > Would you like so send a patch for veth.c too?
>
> Ah, this is where Liu Dinghao got the veth suggestion :)
>
> Does vxcan actually need this patch?
>
> static void vxcan_setup(struct net_device *dev)
> {
> 	[...]
>          dev->needs_free_netdev  = true;

Oh!

In fact the vxcan.c is really similar to veth.c in these code snippets - 
so I wondered why this never had been seen in veth.c.

Then vxcan.c doesn't need that patch too :-/

Thanks for the heads up!

@Marc: Can you please make sure that it doesn't get into upstream? Tnx!

Best,
Oliver