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/inet_diag.c b/net/ipv4/inet_diag.c
index abfbe49..e4d16fc 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -99,6 +99,7 @@
+ nla_total_size(1) /* INET_DIAG_SHUTDOWN */
+ nla_total_size(1) /* INET_DIAG_TOS */
+ nla_total_size(1) /* INET_DIAG_TCLASS */
+ + nla_total_size(4) /* INET_DIAG_MARK */
+ nla_total_size(sizeof(struct inet_diag_meminfo))
+ nla_total_size(sizeof(struct inet_diag_msg))
+ nla_total_size(SK_MEMINFO_VARS * sizeof(u32))
@@ -109,7 +110,8 @@
int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
struct inet_diag_msg *r, int ext,
- struct user_namespace *user_ns)
+ struct user_namespace *user_ns,
+ bool net_admin)
{
const struct inet_sock *inet = inet_sk(sk);
@@ -136,6 +138,9 @@
}
#endif
+ if (net_admin && nla_put_u32(skb, INET_DIAG_MARK, sk->sk_mark))
+ goto errout;
+
r->idiag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
r->idiag_inode = sock_i_ino(sk);
@@ -149,7 +154,8 @@
struct sk_buff *skb, const struct inet_diag_req_v2 *req,
struct user_namespace *user_ns,
u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh)
+ const struct nlmsghdr *unlh,
+ bool net_admin)
{
const struct tcp_congestion_ops *ca_ops;
const struct inet_diag_handler *handler;
@@ -175,7 +181,7 @@
r->idiag_timer = 0;
r->idiag_retrans = 0;
- if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns))
+ if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin))
goto errout;
if (ext & (1 << (INET_DIAG_MEMINFO - 1))) {
@@ -274,10 +280,11 @@
const struct inet_diag_req_v2 *req,
struct user_namespace *user_ns,
u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh)
+ const struct nlmsghdr *unlh,
+ bool net_admin)
{
- return inet_sk_diag_fill(sk, inet_csk(sk), skb, req,
- user_ns, portid, seq, nlmsg_flags, unlh);
+ return inet_sk_diag_fill(sk, inet_csk(sk), skb, req, user_ns,
+ portid, seq, nlmsg_flags, unlh, net_admin);
}
static int inet_twsk_diag_fill(struct sock *sk,
@@ -319,8 +326,9 @@
static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh)
+ const struct nlmsghdr *unlh, bool net_admin)
{
+ struct request_sock *reqsk = inet_reqsk(sk);
struct inet_diag_msg *r;
struct nlmsghdr *nlh;
long tmo;
@@ -334,7 +342,7 @@
inet_diag_msg_common_fill(r, sk);
r->idiag_state = TCP_SYN_RECV;
r->idiag_timer = 1;
- r->idiag_retrans = inet_reqsk(sk)->num_retrans;
+ r->idiag_retrans = reqsk->num_retrans;
BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=
offsetof(struct sock, sk_cookie));
@@ -346,6 +354,10 @@
r->idiag_uid = 0;
r->idiag_inode = 0;
+ if (net_admin && nla_put_u32(skb, INET_DIAG_MARK,
+ inet_rsk(reqsk)->ir_mark))
+ return -EMSGSIZE;
+
nlmsg_end(skb, nlh);
return 0;
}
@@ -354,7 +366,7 @@
const struct inet_diag_req_v2 *r,
struct user_namespace *user_ns,
u32 portid, u32 seq, u16 nlmsg_flags,
- const struct nlmsghdr *unlh)
+ const struct nlmsghdr *unlh, bool net_admin)
{
if (sk->sk_state == TCP_TIME_WAIT)
return inet_twsk_diag_fill(sk, skb, portid, seq,
@@ -362,10 +374,10 @@
if (sk->sk_state == TCP_NEW_SYN_RECV)
return inet_req_diag_fill(sk, skb, portid, seq,
- nlmsg_flags, unlh);
+ nlmsg_flags, unlh, net_admin);
return inet_csk_diag_fill(sk, skb, r, user_ns, portid, seq,
- nlmsg_flags, unlh);
+ nlmsg_flags, unlh, net_admin);
}
struct sock *inet_diag_find_one_icsk(struct net *net,
@@ -435,7 +447,8 @@
err = sk_diag_fill(sk, 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);
nlmsg_free(rep);
@@ -796,7 +809,8 @@
struct sk_buff *skb,
struct netlink_callback *cb,
const struct inet_diag_req_v2 *r,
- const struct nlattr *bc)
+ const struct nlattr *bc,
+ bool net_admin)
{
if (!inet_diag_bc_sk(bc, sk))
return 0;
@@ -804,7 +818,8 @@
return inet_csk_diag_fill(sk, skb, r,
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 void twsk_build_assert(void)
@@ -840,6 +855,7 @@
struct net *net = sock_net(skb->sk);
int i, num, s_i, s_num;
u32 idiag_states = r->idiag_states;
+ bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
if (idiag_states & TCPF_SYN_RECV)
idiag_states |= TCPF_NEW_SYN_RECV;
@@ -880,7 +896,8 @@
cb->args[3] > 0)
goto next_listen;
- if (inet_csk_diag_dump(sk, skb, cb, r, bc) < 0) {
+ if (inet_csk_diag_dump(sk, skb, cb, r,
+ bc, net_admin) < 0) {
spin_unlock_bh(&ilb->lock);
goto done;
}
@@ -948,7 +965,7 @@
sk_user_ns(NETLINK_CB(cb->skb).sk),
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, NLM_F_MULTI,
- cb->nlh);
+ cb->nlh, net_admin);
if (res < 0) {
spin_unlock_bh(lock);
goto done;