From: Patrick McHardy <kaber@trash.net>
Date: Tue, 19 Jun 2007 05:30:15 +0000 (-0700)
Subject: [XFRM]: Fix MTU calculation for non-ESP SAs
X-Git-Tag: v2.6.22-rc6~39^2~2
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=281216177a407f78cfd650ee4391afc487577193;p=linux-2.6

[XFRM]: Fix MTU calculation for non-ESP SAs

My IPsec MTU optimization patch introduced a regression in MTU calculation
for non-ESP SAs, the SA's header_len needs to be subtracted from the MTU if
the transform doesn't provide a ->get_mtu() function.

Reported-and-tested-by: Marco Berizzi <pupilla@hotmail.com>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 85f3f43a6c..dfacb9c2a6 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -1729,7 +1729,7 @@ int xfrm_state_mtu(struct xfrm_state *x, int mtu)
 	    x->type && x->type->get_mtu)
 		res = x->type->get_mtu(x, mtu);
 	else
-		res = mtu;
+		res = mtu - x->props.header_len;
 	spin_unlock_bh(&x->lock);
 	return res;
 }