bridge: fix mdb info leaks
The bridging code discloses heap and stack bytes via the RTM_GETMDB
netlink interface and via the notify messages send to group RTNLGRP_MDB
afer a successful add/del.
Fix both cases by initializing all unset members/padding bytes with
memset(0).
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 9f97b85..ee79f3f 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -80,6 +80,7 @@
port = p->port;
if (port) {
struct br_mdb_entry e;
+ memset(&e, 0, sizeof(e));
e.ifindex = port->dev->ifindex;
e.state = p->state;
if (p->addr.proto == htons(ETH_P_IP))
@@ -136,6 +137,7 @@
break;
bpm = nlmsg_data(nlh);
+ memset(bpm, 0, sizeof(*bpm));
bpm->ifindex = dev->ifindex;
if (br_mdb_fill_info(skb, cb, dev) < 0)
goto out;
@@ -171,6 +173,7 @@
return -EMSGSIZE;
bpm = nlmsg_data(nlh);
+ memset(bpm, 0, sizeof(*bpm));
bpm->family = AF_BRIDGE;
bpm->ifindex = dev->ifindex;
nest = nla_nest_start(skb, MDBA_MDB);
@@ -228,6 +231,7 @@
{
struct br_mdb_entry entry;
+ memset(&entry, 0, sizeof(entry));
entry.ifindex = port->dev->ifindex;
entry.addr.proto = group->proto;
entry.addr.u.ip4 = group->u.ip4;