skb: allow skb_scrub_packet() to be used by tunnels

This function was only used when a packet was sent to another netns. Now, it can
also be used after tunnel encapsulation or decapsulation.

Only skb_orphan() should not be done when a packet is not crossing netns.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 7 deletions

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 2c3d0f53d198..d81cff119f73 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3500,17 +3500,22 @@ bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from,
 EXPORT_SYMBOL(skb_try_coalesce);
 
 /**
- * skb_scrub_packet - scrub an skb before sending it to another netns
+ * skb_scrub_packet - scrub an skb
  *
  * @skb: buffer to clean
- *
- * skb_scrub_packet can be used to clean an skb before injecting it in
- * another namespace. We have to clear all information in the skb that
- * could impact namespace isolation.
+ * @xnet: packet is crossing netns
+ *
+ * skb_scrub_packet can be used after encapsulating or decapsulting a packet
+ * into/from a tunnel. Some information have to be cleared during these
+ * operations.
+ * skb_scrub_packet can also be used to clean a skb before injecting it in
+ * another namespace (@xnet == true). We have to clear all information in the
+ * skb that could impact namespace isolation.
  */
-void skb_scrub_packet(struct sk_buff *skb)
+void skb_scrub_packet(struct sk_buff *skb, bool xnet)
 {
-	skb_orphan(skb);
+	if (xnet)
+		skb_orphan(skb);
 	skb->tstamp.tv64 = 0;
 	skb->pkt_type = PACKET_HOST;
 	skb->skb_iif = 0;