3.11.10.2 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx> commit 0e033e04c2678dbbe74a46b23fffb7bb918c288e upstream. 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@xxxxxxxxx> Cc: Pravin B Shelar <pshelar@xxxxxxxxxx> Signed-off-by: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> [ luis: backported to 3.11: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx> --- net/ipv6/udp_offload.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c index 5d1b8d7..657914b 100644 --- a/net/ipv6/udp_offload.c +++ b/net/ipv6/udp_offload.c @@ -86,7 +86,7 @@ static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, /* 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; } -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html