[PATCH 4.18 119/150] udp6: fix encap return code for resubmitting

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Paolo Abeni <pabeni@xxxxxxxxxx>

[ Upstream commit 84dad55951b0d009372ec21760b650634246e144 ]

The commit eb63f2964dbe ("udp6: add missing checks on edumux packet
processing") used the same return code convention of the ipv4 counterpart,
but ipv6 uses the opposite one: positive values means resubmit.

This change addresses the issue, using positive return value for
resubmitting. Also update the related comment, which was broken, too.

Fixes: eb63f2964dbe ("udp6: add missing checks on edumux packet processing")
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/ipv6/udp.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -762,11 +762,9 @@ static int udp6_unicast_rcv_skb(struct s
 
 	ret = udpv6_queue_rcv_skb(sk, skb);
 
-	/* a return value > 0 means to resubmit the input, but
-	 * it wants the return to be -protocol, or 0
-	 */
+	/* a return value > 0 means to resubmit the input */
 	if (ret > 0)
-		return -ret;
+		return ret;
 	return 0;
 }