From: Jesper Dangaard Brouer <brouer@redhat.com>
Date: Mon, 15 Nov 2021 21:36:25 +0100
Subject: igc: AF_XDP zero-copy metadata adjust breaks SKBs on XDP_PASS
Patch-mainline: v5.17-rc1
Git-commit: 4fa8fcd3440101dbacf4fae91de69877ef751977
References: git-fixes
Driver already implicitly supports XDP metadata access in AF_XDP
zero-copy mode, as xsk_buff_pool's xp_alloc() naturally set xdp_buff
data_meta equal data.
This works fine for XDP and AF_XDP, but if a BPF-prog adjust via
bpf_xdp_adjust_meta() and choose to call XDP_PASS, then igc function
igc_construct_skb_zc() will construct an invalid SKB packet. The
function correctly include the xdp->data_meta area in the memcpy, but
forgot to pull header to take metasize into account.
Fixes: fc9df2a0b520 ("igc: Enable RX via AF_XDP zero-copy")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Nechama Kraus <nechamax.kraus@linux.intel.com>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/intel/igc/igc_main.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -2448,8 +2448,10 @@ static struct sk_buff *igc_construct_skb
skb_reserve(skb, xdp->data_meta - xdp->data_hard_start);
memcpy(__skb_put(skb, totalsize), xdp->data_meta, totalsize);
- if (metasize)
+ if (metasize) {
skb_metadata_set(skb, metasize);
+ __skb_pull(skb, metasize);
+ }
return skb;
}