networking: make skb_put & friends return void pointers

It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 6 insertions, 6 deletions

diff --git a/net/ipv4/netfilter/ipt_SYNPROXY.c b/net/ipv4/netfilter/ipt_SYNPROXY.c
index af2b69b6895f..f1528f7175a8 100644
--- a/net/ipv4/netfilter/ipt_SYNPROXY.c
+++ b/net/ipv4/netfilter/ipt_SYNPROXY.c
@@ -24,7 +24,7 @@ synproxy_build_ip(struct net *net, struct sk_buff *skb, __be32 saddr,
 	struct iphdr *iph;
 
 	skb_reset_network_header(skb);
-	iph = (struct iphdr *)skb_put(skb, sizeof(*iph));
+	iph = skb_put(skb, sizeof(*iph));
 	iph->version	= 4;
 	iph->ihl	= sizeof(*iph) / 4;
 	iph->tos	= 0;
@@ -91,7 +91,7 @@ synproxy_send_client_synack(struct net *net,
 	niph = synproxy_build_ip(net, nskb, iph->daddr, iph->saddr);
 
 	skb_reset_transport_header(nskb);
-	nth = (struct tcphdr *)skb_put(nskb, tcp_hdr_size);
+	nth = skb_put(nskb, tcp_hdr_size);
 	nth->source	= th->dest;
 	nth->dest	= th->source;
 	nth->seq	= htonl(__cookie_v4_init_sequence(iph, th, &mss));
@@ -133,7 +133,7 @@ synproxy_send_server_syn(struct net *net,
 	niph = synproxy_build_ip(net, nskb, iph->saddr, iph->daddr);
 
 	skb_reset_transport_header(nskb);
-	nth = (struct tcphdr *)skb_put(nskb, tcp_hdr_size);
+	nth = skb_put(nskb, tcp_hdr_size);
 	nth->source	= th->source;
 	nth->dest	= th->dest;
 	nth->seq	= htonl(recv_seq - 1);
@@ -178,7 +178,7 @@ synproxy_send_server_ack(struct net *net,
 	niph = synproxy_build_ip(net, nskb, iph->daddr, iph->saddr);
 
 	skb_reset_transport_header(nskb);
-	nth = (struct tcphdr *)skb_put(nskb, tcp_hdr_size);
+	nth = skb_put(nskb, tcp_hdr_size);
 	nth->source	= th->dest;
 	nth->dest	= th->source;
 	nth->seq	= htonl(ntohl(th->ack_seq));
@@ -216,7 +216,7 @@ synproxy_send_client_ack(struct net *net,
 	niph = synproxy_build_ip(net, nskb, iph->saddr, iph->daddr);
 
 	skb_reset_transport_header(nskb);
-	nth = (struct tcphdr *)skb_put(nskb, tcp_hdr_size);
+	nth = skb_put(nskb, tcp_hdr_size);
 	nth->source	= th->source;
 	nth->dest	= th->dest;
 	nth->seq	= htonl(ntohl(th->seq) + 1);
diff --git a/net/ipv4/netfilter/nf_reject_ipv4.c b/net/ipv4/netfilter/nf_reject_ipv4.c
index 52b7dcc5aaf3..eeacbdaf7cdf 100644
--- a/net/ipv4/netfilter/nf_reject_ipv4.c
+++ b/net/ipv4/netfilter/nf_reject_ipv4.c
@@ -51,7 +51,7 @@ struct iphdr *nf_reject_iphdr_put(struct sk_buff *nskb,
 	struct iphdr *niph, *oiph = ip_hdr(oldskb);
 
 	skb_reset_network_header(nskb);
-	niph = (struct iphdr *)skb_put(nskb, sizeof(struct iphdr));
+	niph = skb_put(nskb, sizeof(struct iphdr));
 	niph->version	= 4;
 	niph->ihl	= sizeof(struct iphdr) / 4;
 	niph->tos	= 0;