rtnl: stats - add missing netlink message size checks

We miss to check if the netlink message is actually big enough to contain
a struct if_stats_msg.

Add a check to prevent userland from sending us short messages that would
make us access memory beyond the end of the message.

Fixes: 10c9ead9f3 ("rtnetlink: add new RTM_GETSTATS message to dump...")
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Mathias Krause 2016-12-28 17:52:15 +01:00 committed by David S. Miller
parent b2eb09af73
commit 4775cc1f2d

View File

@ -3898,6 +3898,9 @@ static int rtnl_stats_get(struct sk_buff *skb, struct nlmsghdr *nlh)
u32 filter_mask;
int err;
if (nlmsg_len(nlh) < sizeof(*ifsm))
return -EINVAL;
ifsm = nlmsg_data(nlh);
if (ifsm->ifindex > 0)
dev = __dev_get_by_index(net, ifsm->ifindex);
@ -3947,6 +3950,9 @@ static int rtnl_stats_dump(struct sk_buff *skb, struct netlink_callback *cb)
cb->seq = net->dev_base_seq;
if (nlmsg_len(cb->nlh) < sizeof(*ifsm))
return -EINVAL;
ifsm = nlmsg_data(cb->nlh);
filter_mask = ifsm->filter_mask;
if (!filter_mask)