4d0fcf6fc21c86703ac5c1bfa0fd0df0909dfe90
[openwrt/openwrt.git] / target / linux / generic / backport-4.9 / 023-4-sr9700-use-skb_cow_head-to-deal-with-cloned-skbs.patch
1 From d532c1082f68176363ed766d09bf187616e282fe Mon Sep 17 00:00:00 2001
2 From: Eric Dumazet <edumazet@google.com>
3 Date: Wed, 19 Apr 2017 09:59:23 -0700
4 Subject: [PATCH] sr9700: 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: c9b37458e956 ("USB2NET : SR9700 : One chip USB 1.1 USB2NET SR9700Device Driver Support")
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/sr9700.c | 9 ++-------
17 1 file changed, 2 insertions(+), 7 deletions(-)
18
19 --- a/drivers/net/usb/sr9700.c
20 +++ b/drivers/net/usb/sr9700.c
21 @@ -456,14 +456,9 @@ static struct sk_buff *sr9700_tx_fixup(s
22
23 len = skb->len;
24
25 - if (skb_headroom(skb) < SR_TX_OVERHEAD) {
26 - struct sk_buff *skb2;
27 -
28 - skb2 = skb_copy_expand(skb, SR_TX_OVERHEAD, 0, flags);
29 + if (skb_cow_head(skb, SR_TX_OVERHEAD)) {
30 dev_kfree_skb_any(skb);
31 - skb = skb2;
32 - if (!skb)
33 - return NULL;
34 + return NULL;
35 }
36
37 __skb_push(skb, SR_TX_OVERHEAD);