sock_diag: align nlattr properly when needed

I also fix the value of INET_DIAG_MAX. It's wrong since commit 8f840e47f190
which is only in net-next right now, thus I didn't make a separate patch.

Fixes: 8f840e47f190 ("sctp: add the sctp_diag.c file")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/inet_diag.h

@@ -115,9 +115,11 @@ enum {
 	INET_DIAG_SKV6ONLY,
 	INET_DIAG_LOCALS,
 	INET_DIAG_PEERS,
+	INET_DIAG_PAD,
+	__INET_DIAG_MAX,
 };
 
-#define INET_DIAG_MAX INET_DIAG_SKV6ONLY
+#define INET_DIAG_MAX (__INET_DIAG_MAX - 1)
 
 /* INET_DIAG_MEM */
 

net/core/sock_diag.c

@@ -120,7 +120,7 @@ static size_t sock_diag_nlmsg_size(void)
 {
 	return NLMSG_ALIGN(sizeof(struct inet_diag_msg)
 	       + nla_total_size(sizeof(u8)) /* INET_DIAG_PROTOCOL */
-	       + nla_total_size(sizeof(struct tcp_info))); /* INET_DIAG_INFO */
+	       + nla_total_size_64bit(sizeof(struct tcp_info))); /* INET_DIAG_INFO */
 }
 
 static void sock_diag_broadcast_destroy_work(struct work_struct *work)

net/ipv4/inet_diag.c

@@ -220,8 +220,9 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
 	}
 
 	if ((ext & (1 << (INET_DIAG_INFO - 1))) && handler->idiag_info_size) {
-		attr = nla_reserve(skb, INET_DIAG_INFO,
-				   handler->idiag_info_size);
+		attr = nla_reserve_64bit(skb, INET_DIAG_INFO,
+					 handler->idiag_info_size,
+					 INET_DIAG_PAD);
 		if (!attr)
 			goto errout;
 
@@ -1078,7 +1079,9 @@ int inet_diag_handler_get_info(struct sk_buff *skb, struct sock *sk)
 	}
 
 	attr = handler->idiag_info_size
-		? nla_reserve(skb, INET_DIAG_INFO, handler->idiag_info_size)
+		? nla_reserve_64bit(skb, INET_DIAG_INFO,
+				    handler->idiag_info_size,
+				    INET_DIAG_PAD)
 		: NULL;
 	if (attr)
 		info = nla_data(attr);

net/sctp/sctp_diag.c

@@ -161,8 +161,9 @@ static int inet_sctp_diag_fill(struct sock *sk, struct sctp_association *asoc,
 	if (ext & (1 << (INET_DIAG_INFO - 1))) {
 		struct nlattr *attr;
 
-		attr = nla_reserve(skb, INET_DIAG_INFO,
-				   sizeof(struct sctp_info));
+		attr = nla_reserve_64bit(skb, INET_DIAG_INFO,
+					 sizeof(struct sctp_info),
+					 INET_DIAG_PAD);
 		if (!attr)
 			goto errout;