diff options
| author | Shreyansh Chouhan <chouhan.shreyansh630@gmail.com> | 2021-08-21 12:44:24 +0530 |
|---|---|---|
| committer | Todd Kjos <tkjos@google.com> | 2021-11-17 17:14:28 -0800 |
| commit | 0875b76a11e991c1b5682261ed8fd82002ab7975 (patch) | |
| tree | 6469058ba7138c8e7c857a19296b425a46b3893b /net | |
| parent | bf88ff8595925cd73a7c16b1a3b2d9aaf0467d5e (diff) | |
BACKPORT: ip_gre: add validation for csum_start
[ Upstream commit 1d011c4803c72f3907eccfc1ec63caefb852fcbf ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: I9dca612e35d2fc085f183ff9bcdcfa4b9cba3d0a
Bug: 150694665
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/ip_gre.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 900ee28bda99..63f7bacf628a 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -502,6 +502,10 @@ static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, static struct sk_buff *gre_handle_offloads(struct sk_buff *skb, bool csum) { + unsigned char *skb_checksum_start = skb->head + skb->csum_start; + + if (csum && skb_checksum_start < skb->data) + return ERR_PTR(-EINVAL); return iptunnel_handle_offloads(skb, csum, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); } |