diff options
| author | Jiri Benc <jbenc@redhat.com> | 2013-11-07 22:59:19 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-11-09 00:12:11 +0400 |
| commit | cdbe7c2d6d485459801838c244c409b938e32df5 (patch) | |
| tree | adaff9745719732f3ff93abae3f52fa94b80db18 /net | |
| parent | 13eb2ab2d33c57ebddc57437a7d341995fc9138c (diff) | |
| download | linux-cdbe7c2d6d485459801838c244c409b938e32df5.tar.xz | |
nfnetlink: do not ack malformed messages
Commit 0628b123c96d ("netfilter: nfnetlink: add batch support and use it
from nf_tables") introduced a bug leading to various crashes in netlink_ack
when netlink message with invalid nlmsg_len was sent by an unprivileged
user.
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/nfnetlink.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index 027f16af51a0..046aa13b4fea 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -363,13 +363,15 @@ static void nfnetlink_rcv(struct sk_buff *skb) struct net *net = sock_net(skb->sk); int msglen; - if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) - return netlink_ack(skb, nlh, -EPERM); - if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len) return; + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) { + netlink_ack(skb, nlh, -EPERM); + return; + } + if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN) { struct nfgenmsg *nfgenmsg; |