From 4666248379e95f659710e2f5ea69883cf799b40b Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Mon, 6 Sep 2021 10:27:38 -0400 Subject: [PATCH] ip6_gre: Revert "ip6_gre: add validation for csum_start" [ Upstream commit fe63339ef36bfb1cc12962015a9b254170eea057 ] This reverts commit 9cf448c200ba9935baa94e7a0964598ce947db9d. This commit was added for equivalence with a similar fix to ip_gre. That fix proved to have a bug. Upon closer inspection, ip6_gre is not susceptible to the original bug. So revert the unnecessary extra check. In short, ipgre_xmit calls skb_pull to remove ipv4 headers previously inserted by dev_hard_header. ip6gre_tunnel_xmit does not. Link: https://lore.kernel.org/netdev/CA+FuTSe+vJgTVLc9SojGuN-f9YQ+xWLPKE_S4f=f+w+_P2hgUg@mail.gmail.com/#t Fixes: 9cf448c200ba ("ip6_gre: add validation for csum_start") Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv6/ip6_gre.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 7a5e90e093630..bc224f917bbd5 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -629,8 +629,6 @@ static int gre_rcv(struct sk_buff *skb) static int gre_handle_offloads(struct sk_buff *skb, bool csum) { - if (csum && skb_checksum_start(skb) < skb->data) - return -EINVAL; return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); }