[PATCH 5.7 72/79] openvswitch: Prevent kernel-infoleak in ovs_ct_put_key()

Greg Kroah-Hartman
2020-08-10T15:38:39Z

From: Peilin Ye <yepeilin.cs@gmail.com>

[ Upstream commit 9aba6c5b49254d5bee927d81593ed4429e91d4ae ]

ovs_ct_put_key() is potentially copying uninitialized kernel stack memory
into socket buffers, since the compiler may leave a 3-byte hole at the end
of `struct ovs_key_ct_tuple_ipv4` and `struct ovs_key_ct_tuple_ipv6`. Fix
it by initializing `orig` with memset().

Fixes: 9dd7f8907c37 ("openvswitch: Add original direction conntrack tuple to sw_flow_key.")
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/openvswitch/conntrack.c | 38 ++++++++++++++++++++------------------
1 file changed, 20 insertions(+), 18 deletions(-)

--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -276,10 +276,6 @@ void ovs_ct_fill_key(const struct sk_buf
ovs_ct_update_key(skb, NULL, key, false, false);
}

-#define IN6_ADDR_INITIALIZER(ADDR) \
- { (ADDR).s6_addr32[0], (ADDR).s6_addr32[1], \
- (ADDR).s6_addr32[2], (ADDR).s6_addr32[3] }
-
int ovs_ct_put_key(const struct sw_flow_key *swkey,
const struct sw_flow_key *output, struct sk_buff *skb)
{
@@ -301,24 +297,30 @@ int ovs_ct_put_key(const struct sw_flow_

if (swkey->ct_orig_proto) {
if (swkey->eth.type == htons(ETH_P_IP)) {
- struct ovs_key_ct_tuple_ipv4 orig = {
- output->ipv4.ct_orig.src,
- output->ipv4.ct_orig.dst,
- output->ct.orig_tp.src,
- output->ct.orig_tp.dst,
- output->ct_orig_proto,
- };
+ struct ovs_key_ct_tuple_ipv4 orig;
+
+ memset(&orig, 0, sizeof(orig));
+ orig.ipv4_src = output->ipv4.ct_orig.src;
+ orig.ipv4_dst = output->ipv4.ct_orig.dst;
+ orig.src_port = output->ct.orig_tp.src;
+ orig.dst_port = output->ct.orig_tp.dst;
+ orig.ipv4_proto = output->ct_orig_proto;
+
if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4,
sizeof(orig), &orig))
return -EMSGSIZE;
} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
- struct ovs_key_ct_tuple_ipv6 orig = {
- IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.src),
- IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.dst),
- output->ct.orig_tp.src,
- output->ct.orig_tp.dst,
- output->ct_orig_proto,
- };
+ struct ovs_key_ct_tuple_ipv6 orig;
+
+ memset(&orig, 0, sizeof(orig));
+ memcpy(orig.ipv6_src, output->ipv6.ct_orig.src.s6_addr32,
+ sizeof(orig.ipv6_src));
+ memcpy(orig.ipv6_dst, output->ipv6.ct_orig.dst.s6_addr32,
+ sizeof(orig.ipv6_dst));
+ orig.src_port = output->ct.orig_tp.src;
+ orig.dst_port = output->ct.orig_tp.dst;
+ orig.ipv6_proto = output->ct_orig_proto;
+
if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6,
sizeof(orig), &orig))
return -EMSGSIZE;