From b0c64eda9996479c9b135c23f5b18a0314af4a98 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 28 Oct 2019 23:19:35 +0800 Subject: erspan: fix the tun_info options_len check for erspan [ 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 Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/ip_gre.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net/ipv4/ip_gre.c') diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 347be2ea78d4..71ff2531d973 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -592,6 +592,9 @@ static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev, 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; -- cgit v1.2.3