[PATCH net-next] net: ipv4: Move ip_options_fragment() out of loop

From: Yajun Deng
Date: Sun Aug 22 2021 - 23:18:22 EST


The ip_options_fragment() only called when iter->offset is equal to zero,
so move it out of loop, and inline 'Copy the flags to each fragment.'
As also, remove the unused parameter in ip_frag_ipcb().

Signed-off-by: Yajun Deng <yajun.deng@xxxxxxxxx>
---
net/ipv4/ip_output.c | 19 ++++---------------
1 file changed, 4 insertions(+), 15 deletions(-)

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 6b04a88466b2..9a8f05d5476e 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -606,18 +606,6 @@ void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
}
EXPORT_SYMBOL(ip_fraglist_init);

-static void ip_fraglist_ipcb_prepare(struct sk_buff *skb,
- struct ip_fraglist_iter *iter)
-{
- struct sk_buff *to = iter->frag;
-
- /* Copy the flags to each fragment. */
- IPCB(to)->flags = IPCB(skb)->flags;
-
- if (iter->offset == 0)
- ip_options_fragment(to);
-}
-
void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter)
{
unsigned int hlen = iter->hlen;
@@ -663,7 +651,7 @@ void ip_frag_init(struct sk_buff *skb, unsigned int hlen,
EXPORT_SYMBOL(ip_frag_init);

static void ip_frag_ipcb(struct sk_buff *from, struct sk_buff *to,
- bool first_frag, struct ip_frag_state *state)
+ bool first_frag)
{
/* Copy the flags to each fragment. */
IPCB(to)->flags = IPCB(from)->flags;
@@ -837,12 +825,13 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,

/* Everything is OK. Generate! */
ip_fraglist_init(skb, iph, hlen, &iter);
+ ip_options_fragment(iter.frag);

for (;;) {
/* Prepare header of the next frame,
* before previous one went down. */
if (iter.frag) {
- ip_fraglist_ipcb_prepare(skb, &iter);
+ IPCB(iter.frag)->flags = IPCB(skb)->flags;
ip_fraglist_prepare(skb, &iter);
}

@@ -897,7 +886,7 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
err = PTR_ERR(skb2);
goto fail;
}
- ip_frag_ipcb(skb, skb2, first_frag, &state);
+ ip_frag_ipcb(skb, skb2, first_frag);

/*
* Put this fragment into the sending queue.
--
2.32.0