[PATCH net] ipvs: Always clear ipvs_property flag in skb_scrub_packet()

[Philo Lu]

We found an issue when using bpf_redirect with ipvs NAT mode after
commit ff70202b2d1a ("dev_forward_skb: do not scrub skb mark within
the same name space"). Particularly, we use bpf_redirect to return
the skb directly back to the netif it comes from, i.e., xnet is
false in skb_scrub_packet(), and then ipvs_property is preserved
and SNAT is skipped in the rx path.

ipvs_property has been already cleared when netns is changed in
commit 2b5ec1a5f973 ("netfilter/ipvs: clear ipvs_property flag when
SKB net namespace changed"). This patch just clears it in spite of
netns.

Signed-off-by: Philo Lu <lulie@xxxxxxxxxxxxxxxxx>
---
This is in fact a fix patch, and the issue was found after commit
ff70202b2d1a ("dev_forward_skb: do not scrub skb mark within
the same name space"). But I'm not sure if a "Fixes" tag should be
added to that commit.
---
 net/core/skbuff.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 7b03b64fdcb2..b1c81687e9d8 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -6033,11 +6033,11 @@ void skb_scrub_packet(struct sk_buff *skb, bool xnet)
 	skb->offload_fwd_mark = 0;
 	skb->offload_l3_fwd_mark = 0;
 #endif
+	ipvs_reset(skb);
 
 	if (!xnet)
 		return;
 
-	ipvs_reset(skb);
 	skb->mark = 0;
 	skb_clear_tstamp(skb);
 }
-- 
2.32.0.3.g01195cf9f