Message ID | 20131105014127.GG8832@order.stressinduktion.org |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
From: Hannes Frederic Sowa <hannes@stressinduktion.org> Date: Tue, 5 Nov 2013 02:41:27 +0100 > 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> Applied and queued up for -stable, thanks Hannes. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c index 08e23b0..e7359f9 100644 --- a/net/ipv6/udp_offload.c +++ b/net/ipv6/udp_offload.c @@ -90,7 +90,7 @@ 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; }
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> --- net/ipv6/udp_offload.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)