netfilter/ipvs: clear ipvs_property flag when SKB net namespace changed

BugLink: http://bugs.launchpad.net/bugs/1744794

[ Upstream commit 2b5ec1a5 ]

When run ipvs in two different network namespace at the same host, and one
ipvs transport network traffic to the other network namespace ipvs.
'ipvs_property' flag will make the second ipvs take no effect. So we should
clear 'ipvs_property' when SKB network namespace changed.

Fixes: 621e84d6 ("dev: introduce skb_scrub_packet()")
Signed-off-by: Ye Yin <hustcat@gmail.com>
Signed-off-by: Wei Zhou <chouryzhou@gmail.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

include/linux/skbuff.h

@@ -3405,6 +3405,13 @@ static inline void nf_reset_trace(struct sk_buff *skb)
 #endif
 }
 
+static inline void ipvs_reset(struct sk_buff *skb)
+{
+#if IS_ENABLED(CONFIG_IP_VS)
+	skb->ipvs_property = 0;
+#endif
+}
+
 /* Note: This doesn't put any conntrack and bridge info in dst. */
 static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src,
 			     bool copy)

net/core/skbuff.c

@@ -4300,6 +4300,7 @@ void skb_scrub_packet(struct sk_buff *skb, bool xnet)
 	if (!xnet)
 		return;
 
+	ipvs_reset(skb);
 	skb_orphan(skb);
 	skb->mark = 0;
 }