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@xxxxxxxxxxxxxxx
Fixes: 27b29f63058d ("bpf: add bpf_redirect() helper")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
Tested-by: Siwar Zitouni <siwar.zitouni@xxxxxxxxx>
---
v2 -> v3:
- add a comment in the code
- rework the commit log
v1 -> v2:
- I forgot the 'Tested-by' tag in the v1 :/
include/linux/if_arp.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/include/linux/if_arp.h b/include/linux/if_arp.h
index 1ed52441972f..10a1e81434cb 100644
--- a/include/linux/if_arp.h
+++ b/include/linux/if_arp.h
@@ -53,6 +53,10 @@ 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;
--
2.39.2
