[PATCH 5/5] bridge: Sanitize IFLA_EXT_MASK for AF_BRIDGE:RTM_GETLINK
From: Thomas Graf <tgraf@suug.ch>
Date: 2014-11-26 12:42:34
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 <redacted>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
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) {
--
1.9.3