On Wed, Aug 02, 2023 at 02:21:06PM +0200, Nicolas Dichtel wrote:
> This kind of interface doesn't have a mac header.
Well, PPP does have a link layer header.
Do you instead mean that PPP automatically adds it?
> This patch fixes bpf_redirect() to a ppp interface.
Can you give more details? Which kind of packets are you trying to
redirect to PPP interfaces?
To me this looks like a hack to work around the fact that
ppp_start_xmit() automatically adds a PPP header. Maybe that's the
best we can do given the current state of ppp_generic.c, but the
commit message should be clear about what the real problem is and
why the patch takes this approach to fix or work around it.
> CC: stable@xxxxxxxxxxxxxxx
> Fixes: 27b29f63058d ("bpf: add bpf_redirect() helper")
> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
> Tested-by: Siwar Zitouni <siwar.zitouni@xxxxxxxxx>
> ---
>
> v1 -> v2:
> - I forgot the 'Tested-by' tag in the v1 :/
>
> include/linux/if_arp.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/include/linux/if_arp.h b/include/linux/if_arp.h
> index 1ed52441972f..8efbe29a6f0c 100644
> --- a/include/linux/if_arp.h
> +++ b/include/linux/if_arp.h
> @@ -53,6 +53,7 @@ static inline bool dev_is_mac_header_xmit(const struct net_device *dev)
> case ARPHRD_NONE:
> case ARPHRD_RAWIP:
> case ARPHRD_PIMREG:
> + case ARPHRD_PPP:
> return false;
> default:
> return true;
> --
> 2.39.2
>
>
