diff options
| author | Congyu Liu <liu3101@purdue.edu> | 2022-01-18 14:20:13 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-02-01 17:24:37 +0100 |
| commit | e372ecd455b6ebc7720f52bf4b5f5d44d02f2092 (patch) | |
| tree | a83f0ce8c1adf0a8635bfd6deded58485bb6e82b /net/packet | |
| parent | 20b7af413153f61c92c48938173ba587be4f6524 (diff) | |
net: fix information leakage in /proc/net/ptype
commit 47934e06b65637c88a762d9c98329ae6e3238888 upstream.
In one net namespace, after creating a packet socket without binding
it to a device, users in other net namespaces can observe the new
`packet_type` added by this packet socket by reading `/proc/net/ptype`
file. This is minor information leakage as packet socket is
namespace aware.
Add a net pointer in `packet_type` to keep the net namespace of
of corresponding packet socket. In `ptype_seq_show`, this net pointer
must be checked when it is not NULL.
Fixes: 2feb27dbe00c ("[NETNS]: Minor information leak via /proc/net/ptype file.")
Signed-off-by: Congyu Liu <liu3101@purdue.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/packet')
| -rw-r--r-- | net/packet/af_packet.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 6062bd5bf132..839e1caa57a5 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1715,6 +1715,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) match->prot_hook.dev = po->prot_hook.dev; match->prot_hook.func = packet_rcv_fanout; match->prot_hook.af_packet_priv = match; + match->prot_hook.af_packet_net = read_pnet(&match->net); match->prot_hook.id_match = match_fanout_group; list_add(&match->list, &fanout_list); } @@ -3294,6 +3295,7 @@ static int packet_create(struct net *net, struct socket *sock, int protocol, po->prot_hook.func = packet_rcv_spkt; po->prot_hook.af_packet_priv = sk; + po->prot_hook.af_packet_net = sock_net(sk); if (proto) { po->prot_hook.type = proto; |