inet_diag: Remove indirect sizeof from inet diag handlers

There's an info_size value stored on inet_diag_handler, but for existing
code this value is effectively constant, so just use sizeof(struct tcp_info)
where required.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/inet_diag.h

@@ -141,7 +141,6 @@ struct inet_diag_handler {
 	void			(*idiag_get_info)(struct sock *sk,
 						  struct inet_diag_msg *r,
 						  void *info);
-	__u16                   idiag_info_size;
 	__u16                   idiag_type;
 };
 

net/dccp/diag.c

@@ -52,7 +52,6 @@ static const struct inet_diag_handler dccp_diag_handler = {
 	.idiag_hashinfo	 = &dccp_hashinfo,
 	.idiag_get_info	 = dccp_diag_get_info,
 	.idiag_type	 = IPPROTO_DCCP,
-	.idiag_info_size = sizeof(struct tcp_info),
 };
 
 static int __init dccp_diag_init(void)

net/ipv4/inet_diag.c

@@ -98,8 +98,7 @@ static int inet_csk_diag_fill(struct sock *sk,
 		minfo = INET_DIAG_PUT(skb, INET_DIAG_MEMINFO, sizeof(*minfo));
 
 	if (ext & (1 << (INET_DIAG_INFO - 1)))
-		info = INET_DIAG_PUT(skb, INET_DIAG_INFO,
-				     handler->idiag_info_size);
+		info = INET_DIAG_PUT(skb, INET_DIAG_INFO, sizeof(struct tcp_info));
 
 	if ((ext & (1 << (INET_DIAG_CONG - 1))) && icsk->icsk_ca_ops) {
 		const size_t len = strlen(icsk->icsk_ca_ops->name);
@@ -299,7 +298,7 @@ static int inet_diag_get_exact(struct sk_buff *in_skb,
 	err = -ENOMEM;
 	rep = alloc_skb(NLMSG_SPACE((sizeof(struct inet_diag_msg) +
 				     sizeof(struct inet_diag_meminfo) +
-				     handler->idiag_info_size + 64)),
+				     sizeof(struct tcp_info) + 64)),
 			GFP_KERNEL);
 	if (!rep)
 		goto out;

net/ipv4/tcp_diag.c

@@ -38,7 +38,6 @@ static const struct inet_diag_handler tcp_diag_handler = {
 	.idiag_hashinfo	 = &tcp_hashinfo,
 	.idiag_get_info	 = tcp_diag_get_info,
 	.idiag_type	 = IPPROTO_TCP,
-	.idiag_info_size = sizeof(struct tcp_info),
 };
 
 static int __init tcp_diag_init(void)