[PATCH NET v2 6/7] ax25: use skb_expand_head
From: Vasily Averin
Date: Tue Jul 13 2021 - 16:58:40 EST
Use skb_expand_head() in ax25_transmit_buffer and ax25_rt_build_path.
Unlike skb_realloc_headroom, new helper does not allocate a new skb if possible.
Signed-off-by: Vasily Averin <vvs@xxxxxxxxxxxxx>
---
v2: removed kfree_skb() in ax25_rt_build_path caller ax25_ip_xmit
net/ax25/ax25_ip.c | 4 +---
net/ax25/ax25_out.c | 12 +++---------
net/ax25/ax25_route.c | 13 +++----------
3 files changed, 7 insertions(+), 22 deletions(-)
diff --git a/net/ax25/ax25_ip.c b/net/ax25/ax25_ip.c
index e4f63dd..3624977 100644
--- a/net/ax25/ax25_ip.c
+++ b/net/ax25/ax25_ip.c
@@ -193,10 +193,8 @@ netdev_tx_t ax25_ip_xmit(struct sk_buff *skb)
skb_pull(skb, AX25_KISS_HEADER_LEN);
if (digipeat != NULL) {
- if ((ourskb = ax25_rt_build_path(skb, src, dst, route->digipeat)) == NULL) {
- kfree_skb(skb);
+ if ((ourskb = ax25_rt_build_path(skb, src, dst, route->digipeat)) == NULL)
goto put;
- }
skb = ourskb;
}
diff --git a/net/ax25/ax25_out.c b/net/ax25/ax25_out.c
index f53751b..af4a10e 100644
--- a/net/ax25/ax25_out.c
+++ b/net/ax25/ax25_out.c
@@ -336,18 +336,12 @@ void ax25_transmit_buffer(ax25_cb *ax25, struct sk_buff *skb, int type)
headroom = ax25_addr_size(ax25->digipeat);
- if (skb_headroom(skb) < headroom) {
- if ((skbn = skb_realloc_headroom(skb, headroom)) == NULL) {
+ if (unlikely(skb_headroom(skb) < headroom)) {
+ skb = skb_expand_head(skb, headroom);
+ if (!skb) {
printk(KERN_CRIT "AX.25: ax25_transmit_buffer - out of memory\n");
- kfree_skb(skb);
return;
}
-
- if (skb->sk != NULL)
- skb_set_owner_w(skbn, skb->sk);
-
- consume_skb(skb);
- skb = skbn;
}
ptr = skb_push(skb, headroom);
diff --git a/net/ax25/ax25_route.c b/net/ax25/ax25_route.c
index b40e0bc..d0b2e09 100644
--- a/net/ax25/ax25_route.c
+++ b/net/ax25/ax25_route.c
@@ -441,24 +441,17 @@ int ax25_rt_autobind(ax25_cb *ax25, ax25_address *addr)
struct sk_buff *ax25_rt_build_path(struct sk_buff *skb, ax25_address *src,
ax25_address *dest, ax25_digi *digi)
{
- struct sk_buff *skbn;
unsigned char *bp;
int len;
len = digi->ndigi * AX25_ADDR_LEN;
- if (skb_headroom(skb) < len) {
- if ((skbn = skb_realloc_headroom(skb, len)) == NULL) {
+ if (unlikely(skb_headroom(skb) < len)) {
+ skb = skb_expand_head(skb, len);
+ if (!skb) {
printk(KERN_CRIT "AX.25: ax25_dg_build_path - out of memory\n");
return NULL;
}
-
- if (skb->sk != NULL)
- skb_set_owner_w(skbn, skb->sk);
-
- consume_skb(skb);
-
- skb = skbn;
}
bp = skb_push(skb, len);
--
1.8.3.1