diff options
author | Shreyansh Chouhan <chouhan.shreyansh630@gmail.com> | 2021-08-21 12:44:24 +0530 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2021-08-22 21:24:40 +0100 |
commit | 1d011c4803c72f3907eccfc1ec63caefb852fcbf (patch) | |
tree | 4a1f5079a0345baaee566ad60dc134fb3be704d5 | |
parent | 12d125b4574bd7f602802d94d7b4a55d85aa8e25 (diff) |
ip_gre: add validation for csum_start
Validate csum_start in gre_handle_offloads before we call _gre_xmit so
that we do not crash later when the csum_start value is used in the
lco_csum function call.
This patch deals with ipv4 code.
Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.")
Reported-by: syzbot+ff8e1b9f2f36481e2efc@syzkaller.appspotmail.com
Signed-off-by: Shreyansh Chouhan <chouhan.shreyansh630@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/ipv4/ip_gre.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 12dca0c85f3c..95419b7adf5c 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -473,6 +473,8 @@ static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, 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); } |