sctp: fix the missing put_user when dumping transport thresholds

This issue causes SCTP_PEER_ADDR_THLDS sockopt not to be able to dump
a transport thresholds info.

Fix it by adding 'goto' put_user in sctp_getsockopt_paddr_thresholds.

Fixes: 8add543e ("sctp: add SCTP_FUTURE_ASSOC for SCTP_PEER_ADDR_THLDS sockopt")
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/sctp/socket.c

@@ -7173,7 +7173,7 @@ static int sctp_getsockopt_paddr_thresholds(struct sock *sk,
 		val.spt_pathmaxrxt = trans->pathmaxrxt;
 		val.spt_pathpfthld = trans->pf_retrans;
 
-		return 0;
+		goto out;
 	}
 
 	asoc = sctp_id2assoc(sk, val.spt_assoc_id);
@@ -7191,6 +7191,7 @@ static int sctp_getsockopt_paddr_thresholds(struct sock *sk,
 		val.spt_pathmaxrxt = sp->pathmaxrxt;
 	}
 
+out:
 	if (put_user(len, optlen) || copy_to_user(optval, &val, len))
 		return -EFAULT;