Commit c085c499 authored by Mathias Krause's avatar Mathias Krause Committed by David S. Miller
Browse files

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: default avatarMathias Krause <minipli@googlemail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 84421b99

net/bridge/br_mdb.c

+4 −0
Original line number Diff line number Diff line
@@ -80,6 +80,7 @@ static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb, 
				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 @@ static int br_mdb_dump(struct sk_buff *skb, struct netlink_callback *cb) 
				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 @@ static int nlmsg_populate_mdb_fill(struct sk_buff *skb, 
		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 @@ void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port, 
{

	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;

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