diff options
| author | Kevin Cernekee <cernekee@chromium.org> | 2017-12-06 12:12:27 -0800 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2018-01-01 20:52:09 +0000 |
| commit | df524750e2d1ead01cceed5ffc0b62166c7630dd (patch) | |
| tree | 7113d68f3a305e747b92b7b07748a3c7c9bd2317 /net | |
| parent | fad6474d43e985338e4c2b3bb1a7668cca1f041a (diff) | |
netlink: Add netns check on taps
commit 93c647643b48f0131f02e45da3bd367d80443291 upstream.
Currently, a nlmon link inside a child namespace can observe systemwide
netlink activity. Filter the traffic so that nlmon can only sniff
netlink messages from its own netns.
Test case:
vpnns -- bash -c "ip link add nlmon0 type nlmon; \
ip link set nlmon0 up; \
tcpdump -i nlmon0 -q -w /tmp/nlmon.pcap -U" &
sudo ip xfrm state add src 10.1.1.1 dst 10.1.1.2 proto esp \
spi 0x1 mode transport \
auth sha1 0x6162633132330000000000000000000000000000 \
enc aes 0x00000000000000000000000000000000
grep --binary abc123 /tmp/nlmon.pcap
Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netlink/af_netlink.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 3bf0c16023ec..2eafcffb5f8e 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -216,6 +216,9 @@ static int __netlink_deliver_tap_skb(struct sk_buff *skb, struct sock *sk = skb->sk; int ret = -ENOMEM; + if (!net_eq(dev_net(dev), sock_net(sk))) + return 0; + dev_hold(dev); if (is_vmalloc_addr(skb->head)) |