netdev - Re: [PATCH net] veth: Update XDP feature set when bringing up device

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Tue, 12 Sep 2023 12:07:26 +0200
From: Paolo Abeni <pabeni@...hat.com>
To: Toke Høiland-Jørgensen <toke@...hat.com>, "David S.
 Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, Jakub
 Kicinski <kuba@...nel.org>,  Alexei Starovoitov <ast@...nel.org>, Daniel
 Borkmann <daniel@...earbox.net>, Jesper Dangaard Brouer <hawk@...nel.org>,
 John Fastabend <john.fastabend@...il.com>, Lorenzo Bianconi
 <lorenzo@...nel.org>, Kumar Kartikeya Dwivedi <memxor@...il.com>, Stanislav
 Fomichev <sdf@...gle.com>, Gerhard Engleder
 <gerhard@...leder-embedded.com>, Simon Horman <horms@...nel.org>
Cc: Marek Majtyka <alardam@...il.com>, netdev@...r.kernel.org, 
	bpf@...r.kernel.org
Subject: Re: [PATCH net] veth: Update XDP feature set when bringing up device

Hi,

On Mon, 2023-09-11 at 15:58 +0200, Toke Høiland-Jørgensen wrote:
> There's an early return in veth_set_features() if the device is in a down
> state, which leads to the XDP feature flags not being updated when enabling
> GRO while the device is down. Which in turn leads to XDP_REDIRECT not
> working, because the redirect code now checks the flags.
> 
> Fix this by updating the feature flags after bringing the device up.
> 
> Before this patch:
> 
> NETDEV_XDP_ACT_BASIC:		yes
> NETDEV_XDP_ACT_REDIRECT:	yes
> NETDEV_XDP_ACT_NDO_XMIT:	no
> NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
> NETDEV_XDP_ACT_HW_OFFLOAD:	no
> NETDEV_XDP_ACT_RX_SG:		yes
> NETDEV_XDP_ACT_NDO_XMIT_SG:	no
> 
> After this patch:
> 
> NETDEV_XDP_ACT_BASIC:		yes
> NETDEV_XDP_ACT_REDIRECT:	yes
> NETDEV_XDP_ACT_NDO_XMIT:	yes
> NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
> NETDEV_XDP_ACT_HW_OFFLOAD:	no
> NETDEV_XDP_ACT_RX_SG:		yes
> NETDEV_XDP_ACT_NDO_XMIT_SG:	yes
> 
> Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag")
> Fixes: 66c0e13ad236 ("drivers: net: turn on XDP features")
> Signed-off-by: Toke Høiland-Jørgensen <toke@...hat.com>
> ---
>  drivers/net/veth.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/net/veth.c b/drivers/net/veth.c
> index 9c6f4f83f22b..0deefd1573cf 100644
> --- a/drivers/net/veth.c
> +++ b/drivers/net/veth.c
> @@ -1446,6 +1446,8 @@ static int veth_open(struct net_device *dev)
>  		netif_carrier_on(peer);
>  	}
>  
> +	veth_set_xdp_features(dev);
> +
>  	return 0;
>  }

The patch LGTM, thanks!

I think it would be nice to add some specific self-tests here. Could
you please consider following-up with them?

Thanks,

Paolo