From 035d210f928ce083435b4fd351a26d126c02c927 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Mon, 13 Jul 2015 00:06:02 +0200 Subject: [PATCH] rtnetlink: reject non-IFLA_VF_PORT attributes inside IFLA_VF_PORTS Similarly as in commit 4f7d2cdfdde7 ("rtnetlink: verify IFLA_VF_INFO attributes before passing them to driver"), we have a double nesting of netlink attributes, i.e. IFLA_VF_PORTS only contains IFLA_VF_PORT that is nested itself. While IFLA_VF_PORTS is a verified attribute from ifla_policy[], we only check if the IFLA_VF_PORTS container has IFLA_VF_PORT attributes and then pass the attribute's content itself via nla_parse_nested(). It would be more correct to reject inner types other than IFLA_VF_PORT instead of continuing parsing and also similarly as in commit 4f7d2cdfdde7, to check for a minimum of NLA_HDRLEN. Signed-off-by: Daniel Borkmann Cc: Roopa Prabhu Cc: Scott Feldman Cc: Jason Gunthorpe Acked-by: Roopa Prabhu Signed-off-by: David S. Miller --- net/core/rtnetlink.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 9e433d5..dc004b1 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1804,10 +1804,13 @@ static int do_setlink(const struct sk_buff *skb, goto errout; nla_for_each_nested(attr, tb[IFLA_VF_PORTS], rem) { - if (nla_type(attr) != IFLA_VF_PORT) - continue; - err = nla_parse_nested(port, IFLA_PORT_MAX, - attr, ifla_port_policy); + if (nla_type(attr) != IFLA_VF_PORT || + nla_len(attr) < NLA_HDRLEN) { + err = -EINVAL; + goto errout; + } + err = nla_parse_nested(port, IFLA_PORT_MAX, attr, + ifla_port_policy); if (err < 0) goto errout; if (!port[IFLA_PORT_VF]) { -- 2.7.4