lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[NETFILTER]: Avoid skb_copy/pskb_copy/skb_realloc_headroom

Browse Source 
This patch replaces unnecessary uses of skb_copy, pskb_copy and
skb_realloc_headroom by functions such as skb_make_writable and
pskb_expand_head.

This allows us to remove the double pointers later.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Herbert Xu
2007-10-14 00:39:55 -07:00
committed by David S. Miller
parent af1e1cf073
commit 2ca7b0ac02
10 changed files with 45 additions and 117 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
net/ipv4/netfilter/arpt_mangle.c
View File

@@ -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>
@@ -18,17 +19,8 @@ target(struct sk_buff **pskb,
unsigned char *arpptr;
int pln, hln;
if (skb_shared(*pskb) || skb_cloned(*pskb)) {
struct sk_buff *nskb;
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;
}
if (skb_make_writable(*pskb, (*pskb)->len))
return NF_DROP;
arp = arp_hdr(*pskb);
arpptr = skb_network_header(*pskb) + sizeof(*arp);

22
net/ipv4/netfilter/ip_queue.c
View File

@@ -335,6 +335,7 @@ static int
ipq_mangle_ipv4(ipq_verdict_msg_t *v, struct ipq_queue_entry *e)
{
int diff;
int err;
struct iphdr *user_iph = (struct iphdr *)v->payload;
if (v->data_len < sizeof(*user_iph))
@@ -347,21 +348,14 @@ ipq_mangle_ipv4(ipq_verdict_msg_t *v, struct ipq_queue_entry *e)
if (v->data_len > 0xFFFF)
return -EINVAL;
if (diff > skb_tailroom(e->skb)) {
struct sk_buff *newskb;
newskb = skb_copy_expand(e->skb,
skb_headroom(e->skb),
diff,
GFP_ATOMIC);
if (newskb == NULL) {
printk(KERN_WARNING "ip_queue: OOM "
"in mangle, dropping packet\n");
return -ENOMEM;
err = pskb_expand_head(e->skb, 0,
diff - skb_tailroom(e->skb),
GFP_ATOMIC);
if (err) {
printk(KERN_WARNING "ip_queue: error "
"in mangle, dropping packet: %d\n", -err);
return err;
}
if (e->skb->sk)
skb_set_owner_w(newskb, e->skb->sk);
kfree_skb(e->skb);
e->skb = newskb;
}
skb_put(e->skb, diff);
}

10
net/ipv4/netfilter/nf_nat_helper.c
View File

@@ -113,20 +113,12 @@ static void mangle_contents(struct sk_buff *skb,
/* Unusual, but possible case. */
static int enlarge_skb(struct sk_buff **pskb, unsigned int extra)
{
struct sk_buff *nskb;
if ((*pskb)->len + extra > 65535)
return 0;
nskb = skb_copy_expand(*pskb, skb_headroom(*pskb), extra, GFP_ATOMIC);
if (!nskb)
if (pskb_expand_head(*pskb, 0, extra - skb_tailroom(*pskb), GFP_ATOMIC))
return 0;
/* Transfer socket to new skb. */
if ((*pskb)->sk)
skb_set_owner_w(nskb, (*pskb)->sk);
kfree_skb(*pskb);
*pskb = nskb;
return 1;
}