From: Herbert Xu Date: Tue, 30 Sep 2008 09:03:19 +0000 (-0700) Subject: ipsec: Fix pskb_expand_head corruption in xfrm_state_check_space X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=d01dbeb6af7a0848063033f73c3d146fec7451f3;p=openwrt%2Fstaging%2Fblogic.git ipsec: Fix pskb_expand_head corruption in xfrm_state_check_space We're never supposed to shrink the headroom or tailroom. In fact, shrinking the headroom is a fatal action. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c index ac25b4c0e982..dc50f1e71f76 100644 --- a/net/xfrm/xfrm_output.c +++ b/net/xfrm/xfrm_output.c @@ -27,10 +27,14 @@ static int xfrm_state_check_space(struct xfrm_state *x, struct sk_buff *skb) - skb_headroom(skb); int ntail = dst->dev->needed_tailroom - skb_tailroom(skb); - if (nhead > 0 || ntail > 0) - return pskb_expand_head(skb, nhead, ntail, GFP_ATOMIC); - - return 0; + if (nhead <= 0) { + if (ntail <= 0) + return 0; + nhead = 0; + } else if (ntail < 0) + ntail = 0; + + return pskb_expand_head(skb, nhead, ntail, GFP_ATOMIC); } static int xfrm_output_one(struct sk_buff *skb, int err)