net: inet: diag: expose the socket mark to privileged processes.
This adds the capability for a process that has CAP_NET_ADMIN on
a socket to see the socket mark in socket dumps.
Commit a52e95abf772 ("net: diag: allow socket bytecode filters to
match socket marks") recently gave privileged processes the
ability to filter socket dumps based on mark. This patch is
complementary: it ensures that the mark is also passed to
userspace in the socket's netlink attributes. It is useful for
tools like ss which display information about sockets.
Tested: https://android-review.googlesource.com/270210
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/udp_diag.c b/net/ipv4/udp_diag.c
index 58b79c0..9a89c10 100644
--- a/net/ipv4/udp_diag.c
+++ b/net/ipv4/udp_diag.c
@@ -20,7 +20,7 @@
static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
struct netlink_callback *cb,
const struct inet_diag_req_v2 *req,
- struct nlattr *bc)
+ struct nlattr *bc, bool net_admin)
{
if (!inet_diag_bc_sk(bc, sk))
return 0;
@@ -28,7 +28,7 @@
return inet_sk_diag_fill(sk, NULL, skb, req,
sk_user_ns(NETLINK_CB(cb->skb).sk),
NETLINK_CB(cb->skb).portid,
- cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
+ cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin);
}
static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
@@ -76,7 +76,8 @@
err = inet_sk_diag_fill(sk, NULL, rep, req,
sk_user_ns(NETLINK_CB(in_skb).sk),
NETLINK_CB(in_skb).portid,
- nlh->nlmsg_seq, 0, nlh);
+ nlh->nlmsg_seq, 0, nlh,
+ netlink_net_capable(in_skb, CAP_NET_ADMIN));
if (err < 0) {
WARN_ON(err == -EMSGSIZE);
kfree_skb(rep);
@@ -97,6 +98,7 @@
struct netlink_callback *cb,
const struct inet_diag_req_v2 *r, struct nlattr *bc)
{
+ bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
struct net *net = sock_net(skb->sk);
int num, s_num, slot, s_slot;
@@ -132,7 +134,7 @@
r->id.idiag_dport)
goto next;
- if (sk_diag_dump(sk, skb, cb, r, bc) < 0) {
+ if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) {
spin_unlock_bh(&hslot->lock);
goto done;
}