From aa68c20ff32f9a6fb3ca7f93ed9beae01899d00d Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Wed, 26 Nov 2014 13:42:20 +0100 Subject: [PATCH] bridge: Sanitize IFLA_EXT_MASK for AF_BRIDGE:RTM_GETLINK Only search for IFLA_EXT_MASK if the message actually carries a ifinfomsg header and validate minimal length requirements for IFLA_EXT_MASK. Fixes: 6cbdceeb ("bridge: Dump vlan information from a bridge port") Cc: Vlad Yasevich Signed-off-by: Thomas Graf Signed-off-by: David S. Miller --- net/core/rtnetlink.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 5a853f8..b9b7dfa 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2685,13 +2685,20 @@ static int rtnl_bridge_getlink(struct sk_buff *skb, struct netlink_callback *cb) int idx = 0; u32 portid = NETLINK_CB(cb->skb).portid; u32 seq = cb->nlh->nlmsg_seq; - struct nlattr *extfilt; u32 filter_mask = 0; - extfilt = nlmsg_find_attr(cb->nlh, sizeof(struct ifinfomsg), - IFLA_EXT_MASK); - if (extfilt) - filter_mask = nla_get_u32(extfilt); + if (nlmsg_len(cb->nlh) > sizeof(struct ifinfomsg)) { + struct nlattr *extfilt; + + extfilt = nlmsg_find_attr(cb->nlh, sizeof(struct ifinfomsg), + IFLA_EXT_MASK); + if (extfilt) { + if (nla_len(extfilt) < sizeof(filter_mask)) + return -EINVAL; + + filter_mask = nla_get_u32(extfilt); + } + } rcu_read_lock(); for_each_netdev_rcu(net, dev) { -- 2.7.4