From: Xin Long lucien.xin@gmail.com
[ Upstream commit 2eb8d6d2910cfe3dc67dc056f26f3dd9c63d47cd ]
The check for !md doens't really work for ip_tunnel_info_opts(info) which only does info + 1. Also to avoid out-of-bounds access on info, it should ensure options_len is not less than erspan_metadata in both erspan_xmit() and ip6erspan_tunnel_xmit().
Fixes: 1a66a836da ("gre: add collect_md mode to ERSPAN tunnel") Signed-off-by: Xin Long lucien.xin@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv4/ip_gre.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -592,6 +592,9 @@ static void erspan_fb_xmit(struct sk_buf truncate = true; }
+ if (tun_info->options_len < sizeof(*md)) + goto err_free_rt; + md = ip_tunnel_info_opts(tun_info); if (!md) goto err_free_rt;