[NETFILTER]: annotate {arp,ip,ip6,x}tables with const

[firefly-linux-kernel-4.4.55.git] / net / ipv4 / netfilter / arpt_mangle.c

diff --git a/net/ipv4/netfilter/arpt_mangle.c b/net/ipv4/netfilter/arpt_mangle.c
index c4bdab47597f071c35cb73f45570552777c8ad48..3e732c827fc2e97b341d106bd38577064ddb1c1f 100644 (file)
--- a/net/ipv4/netfilter/arpt_mangle.c
+++ b/net/ipv4/netfilter/arpt_mangle.c
@@ -1,5 +1,6 @@
 /* module that allows mangling of the arp payload */
 #include <linux/module.h>
+#include <linux/netfilter.h>
 #include <linux/netfilter_arp/arpt_mangle.h>
 #include <net/sock.h>
 
@@ -8,57 +9,48 @@ MODULE_AUTHOR("Bart De Schuymer <bdschuym@pandora.be>");
 MODULE_DESCRIPTION("arptables arp payload mangle target");
 
 static unsigned int
-target(struct sk_buff **pskb,
+target(struct sk_buff *skb,
        const struct net_device *in, const struct net_device *out,
        unsigned int hooknum, const struct xt_target *target,
        const void *targinfo)
 {
        const struct arpt_mangle *mangle = targinfo;
-       struct arphdr *arp;
+       const struct arphdr *arp;
        unsigned char *arpptr;
        int pln, hln;
 
-       if (skb_shared(*pskb) || skb_cloned(*pskb)) {
-               struct sk_buff *nskb;
+       if (!skb_make_writable(skb, skb->len))
+               return NF_DROP;
 
-               nskb = skb_copy(*pskb, GFP_ATOMIC);
-               if (!nskb)
-                       return NF_DROP;
-               if ((*pskb)->sk)
-                       skb_set_owner_w(nskb, (*pskb)->sk);
-               kfree_skb(*pskb);
-               *pskb = nskb;
-       }
-
-       arp = arp_hdr(*pskb);
-       arpptr = skb_network_header(*pskb) + sizeof(*arp);
+       arp = arp_hdr(skb);
+       arpptr = skb_network_header(skb) + sizeof(*arp);
        pln = arp->ar_pln;
        hln = arp->ar_hln;
        /* We assume that pln and hln were checked in the match */
        if (mangle->flags & ARPT_MANGLE_SDEV) {
                if (ARPT_DEV_ADDR_LEN_MAX < hln ||
-                  (arpptr + hln > skb_tail_pointer(*pskb)))
+                  (arpptr + hln > skb_tail_pointer(skb)))
                        return NF_DROP;
                memcpy(arpptr, mangle->src_devaddr, hln);
        }
        arpptr += hln;
        if (mangle->flags & ARPT_MANGLE_SIP) {
                if (ARPT_MANGLE_ADDR_LEN_MAX < pln ||
-                  (arpptr + pln > skb_tail_pointer(*pskb)))
+                  (arpptr + pln > skb_tail_pointer(skb)))
                        return NF_DROP;
                memcpy(arpptr, &mangle->u_s.src_ip, pln);
        }
        arpptr += pln;
        if (mangle->flags & ARPT_MANGLE_TDEV) {
                if (ARPT_DEV_ADDR_LEN_MAX < hln ||
-                  (arpptr + hln > skb_tail_pointer(*pskb)))
+                  (arpptr + hln > skb_tail_pointer(skb)))
                        return NF_DROP;
                memcpy(arpptr, mangle->tgt_devaddr, hln);
        }
        arpptr += hln;
        if (mangle->flags & ARPT_MANGLE_TIP) {
                if (ARPT_MANGLE_ADDR_LEN_MAX < pln ||
-                  (arpptr + pln > skb_tail_pointer(*pskb)))
+                  (arpptr + pln > skb_tail_pointer(skb)))
                        return NF_DROP;
                memcpy(arpptr, &mangle->u_t.tgt_ip, pln);
        }