aee8aa98050b0df8d1c56da6cc7dbbb1a9e335ff
[openwrt/openwrt.git] / target / linux / generic / backport-4.9 / 023-3-cx82310_eth-use-skb_cow_head-to-deal-with-cloned-skb.patch
1 From a9e840a2081ed28c2b7caa6a9a0041c950b3c37d Mon Sep 17 00:00:00 2001
2 From: Eric Dumazet <edumazet@google.com>
3 Date: Wed, 19 Apr 2017 09:59:22 -0700
4 Subject: [PATCH] cx82310_eth: use skb_cow_head() to deal with cloned skbs
5
6 We need to ensure there is enough headroom to push extra header,
7 but we also need to check if we are allowed to change headers.
8
9 skb_cow_head() is the proper helper to deal with this.
10
11 Fixes: cc28a20e77b2 ("introduce cx82310_eth: Conexant CX82310-based ADSL router USB ethernet driver")
12 Signed-off-by: Eric Dumazet <edumazet@google.com>
13 Cc: James Hughes <james.hughes@raspberrypi.org>
14 Signed-off-by: David S. Miller <davem@davemloft.net>
15 ---
16 drivers/net/usb/cx82310_eth.c | 7 ++-----
17 1 file changed, 2 insertions(+), 5 deletions(-)
18
19 --- a/drivers/net/usb/cx82310_eth.c
20 +++ b/drivers/net/usb/cx82310_eth.c
21 @@ -293,12 +293,9 @@ static struct sk_buff *cx82310_tx_fixup(
22 {
23 int len = skb->len;
24
25 - if (skb_headroom(skb) < 2) {
26 - struct sk_buff *skb2 = skb_copy_expand(skb, 2, 0, flags);
27 + if (skb_cow_head(skb, 2)) {
28 dev_kfree_skb_any(skb);
29 - skb = skb2;
30 - if (!skb)
31 - return NULL;
32 + return NULL;
33 }
34 skb_push(skb, 2);
35