X-Git-Url: http://git.openwrt.org/?p=openwrt%2Fopenwrt.git;a=blobdiff_plain;f=target%2Flinux%2Fgeneric%2Fbackport-4.9%2F023-5-lan78xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch;fp=target%2Flinux%2Fgeneric%2Fbackport-4.9%2F023-5-lan78xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch;h=ea8279940b540973622c9349019375f66c448bfc;hp=0000000000000000000000000000000000000000;hb=74d00a8c3849c1340efd713eb94b786e304c201f;hpb=de350550ef648d9728351b986b0516fa29465c45

diff --git a/target/linux/generic/backport-4.9/023-5-lan78xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch b/target/linux/generic/backport-4.9/023-5-lan78xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch
new file mode 100644
index 0000000000..ea8279940b
--- /dev/null
+++ b/target/linux/generic/backport-4.9/023-5-lan78xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch
@@ -0,0 +1,38 @@
+From d4ca73591916b760478d2b04334d5dcadc028e9c Mon Sep 17 00:00:00 2001
+From: Eric Dumazet <edumazet@google.com>
+Date: Wed, 19 Apr 2017 09:59:24 -0700
+Subject: [PATCH] lan78xx: use skb_cow_head() to deal with cloned skbs
+
+We need to ensure there is enough headroom to push extra header,
+but we also need to check if we are allowed to change headers.
+
+skb_cow_head() is the proper helper to deal with this.
+
+Fixes: 55d7de9de6c3 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver")
+Signed-off-by: Eric Dumazet <edumazet@google.com>
+Cc: James Hughes <james.hughes@raspberrypi.org>
+Cc: Woojung Huh <woojung.huh@microchip.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/usb/lan78xx.c | 9 ++-------
+ 1 file changed, 2 insertions(+), 7 deletions(-)
+
+--- a/drivers/net/usb/lan78xx.c
++++ b/drivers/net/usb/lan78xx.c
+@@ -2419,14 +2419,9 @@ static struct sk_buff *lan78xx_tx_prep(s
+ {
+ 	u32 tx_cmd_a, tx_cmd_b;
+ 
+-	if (skb_headroom(skb) < TX_OVERHEAD) {
+-		struct sk_buff *skb2;
+-
+-		skb2 = skb_copy_expand(skb, TX_OVERHEAD, 0, flags);
++	if (skb_cow_head(skb, TX_OVERHEAD)) {
+ 		dev_kfree_skb_any(skb);
+-		skb = skb2;
+-		if (!skb)
+-			return NULL;
++		return NULL;
+ 	}
+ 
+ 	if (lan78xx_linearize(skb) < 0)