| From aea39f26c4a2c08bd625bdb35a16ce6edb42f71c Mon Sep 17 00:00:00 2001 |
| From: Hannes Frederic Sowa <hannes@stressinduktion.org> |
| Date: Tue, 5 Nov 2013 02:41:27 +0100 |
| Subject: ipv6: fix headroom calculation in udp6_ufo_fragment |
| |
| From: Hannes Frederic Sowa <hannes@stressinduktion.org> |
| |
| [ Upstream commit 0e033e04c2678dbbe74a46b23fffb7bb918c288e ] |
| |
| Commit 1e2bd517c108816220f262d7954b697af03b5f9c ("udp6: Fix udp |
| fragmentation for tunnel traffic.") changed the calculation if |
| there is enough space to include a fragment header in the skb from a |
| skb->mac_header dervived one to skb_headroom. Because we already peeled |
| off the skb to transport_header this is wrong. Change this back to check |
| if we have enough room before the mac_header. |
| |
| This fixes a panic Saran Neti reported. He used the tbf scheduler which |
| skb_gso_segments the skb. The offsets get negative and we panic in memcpy |
| because the skb was erroneously not expanded at the head. |
| |
| Reported-by: Saran Neti <Saran.Neti@telus.com> |
| Cc: Pravin B Shelar <pshelar@nicira.com> |
| Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/ipv6/udp_offload.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/net/ipv6/udp_offload.c |
| +++ b/net/ipv6/udp_offload.c |
| @@ -85,7 +85,7 @@ static struct sk_buff *udp6_ufo_fragment |
| |
| /* Check if there is enough headroom to insert fragment header. */ |
| tnl_hlen = skb_tnl_header_len(skb); |
| - if (skb_headroom(skb) < (tnl_hlen + frag_hdr_sz)) { |
| + if (skb->mac_header < (tnl_hlen + frag_hdr_sz)) { |
| if (gso_pskb_expand_head(skb, tnl_hlen + frag_hdr_sz)) |
| goto out; |
| } |
