Commit 712491c9 authored Aug 23, 2023 by Nicolas Dichtel Committed by Greg Kroah-Hartman Sep 23, 2023

net: handle ARPHRD_PPP in dev_is_mac_header_xmit()



commit a4f39c9f14a634e4cd35fcd338c239d11fcc73fc upstream.

The goal is to support a bpf_redirect() from an ethernet device (ingress)
to a ppp device (egress).
The l2 header is added automatically by the ppp driver, thus the ethernet
header should be removed.

CC: stable@vger.kernel.org
Fixes: 27b29f63 ("bpf: add bpf_redirect() helper")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Tested-by: Siwar Zitouni <siwar.zitouni@6wind.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 15b37271

include/linux/if_arp.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -52,6 +52,10 @@ static inline bool dev_is_mac_header_xmit(const struct net_device *dev)
		case ARPHRD_NONE:
		case ARPHRD_RAWIP:
		case ARPHRD_PIMREG:
		/* PPP adds its l2 header automatically in ppp_start_xmit().
		* This makes it look like an l3 device to __bpf_redirect() and tcf_mirred_init().
		*/
		case ARPHRD_PPP:
		return false;
		default:
		return true;