From: Ross Lagerwall Date: Mon, 14 Jan 2019 09:16:56 +0000 (+0000) Subject: openvswitch: Avoid OOB read when parsing flow nlattrs X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=04a4af334b971814eedf4e4a413343ad3287d9a9;p=openwrt%2Fstaging%2Fblogic.git openvswitch: Avoid OOB read when parsing flow nlattrs For nested and variable attributes, the expected length of an attribute is not known and marked by a negative number. This results in an OOB read when the expected length is later used to check if the attribute is all zeros. Fix this by using the actual length of the attribute rather than the expected length. Signed-off-by: Ross Lagerwall Acked-by: Pravin B Shelar Signed-off-by: David S. Miller --- diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c index 435a4bdf8f89..691da853bef5 100644 --- a/net/openvswitch/flow_netlink.c +++ b/net/openvswitch/flow_netlink.c @@ -500,7 +500,7 @@ static int __parse_flow_nlattrs(const struct nlattr *attr, return -EINVAL; } - if (!nz || !is_all_zero(nla_data(nla), expected_len)) { + if (!nz || !is_all_zero(nla_data(nla), nla_len(nla))) { attrs |= 1 << type; a[type] = nla; }