tcp: ulp: diag: remove net admin restriction

Since its introduction in commit 61723b3 ("tcp: ulp: add functions
to dump ulp-specific information"), the ULP diag info have been exported
only if the requester had CAP_NET_ADMIN.

It looks like there is nothing sensitive being exported here by the
MPTCP and KTLS layers. So it seems safe to remove this restriction in
order to ease the debugging from the userspace side without requiring
additional capabilities.

Signed-off-by: Matthieu Baerts (NGI0) <[email protected]>

Author: matttbe

net/ipv4/tcp_diag.c

@@ -113,6 +113,7 @@ static int tcp_diag_get_aux(struct sock *sk, bool net_admin,
 			    struct sk_buff *skb)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
+	const struct tcp_ulp_ops *ulp_ops;
 	int err = 0;
 
 #ifdef CONFIG_TCP_MD5SIG
@@ -129,15 +130,13 @@ static int tcp_diag_get_aux(struct sock *sk, bool net_admin,
 	}
 #endif
 
-	if (net_admin) {
-		const struct tcp_ulp_ops *ulp_ops;
-
-		ulp_ops = icsk->icsk_ulp_ops;
-		if (ulp_ops)
-			err = tcp_diag_put_ulp(skb, sk, ulp_ops);
-		if (err)
+	ulp_ops = icsk->icsk_ulp_ops;
+	if (ulp_ops) {
+		err = tcp_diag_put_ulp(skb, sk, ulp_ops);
+		if (err < 0)
 			return err;
 	}
+
 	return 0;
 }
 
@@ -164,7 +163,7 @@ static size_t tcp_diag_get_aux_size(struct sock *sk, bool net_admin)
 	}
 #endif
 
-	if (net_admin && sk_fullsock(sk)) {
+	if (sk_fullsock(sk)) {
 		const struct tcp_ulp_ops *ulp_ops;
 
 		ulp_ops = icsk->icsk_ulp_ops;