From: James Hughes james.hughes@raspberrypi.org
commit e9156cd26a495a18706e796f02a81fee41ec14f4 upstream.
The driver was failing to check that the SKB wasn't cloned before adding checksum data. Replace existing handling to extend/copy the header buffer with skb_cow_head.
Signed-off-by: James Hughes james.hughes@raspberrypi.org Acked-by: Eric Dumazet edumazet@google.com Acked-by: Woojung Huh Woojung.Huh@microchip.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Linus Walleij linus.walleij@linaro.org --- - This was applied upstream in v4.11 - Should be applied to stable v4.9.y --- drivers/net/usb/smsc95xx.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index e29f4c0767eb..e719ecd69d01 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -2011,13 +2011,13 @@ static struct sk_buff *smsc95xx_tx_fixup(struct usbnet *dev, /* We do not advertise SG, so skbs should be already linearized */ BUG_ON(skb_shinfo(skb)->nr_frags);
- if (skb_headroom(skb) < overhead) { - struct sk_buff *skb2 = skb_copy_expand(skb, - overhead, 0, flags); + /* Make writable and expand header space by overhead if required */ + if (skb_cow_head(skb, overhead)) { + /* Must deallocate here as returning NULL to indicate error + * means the skb won't be deallocated in the caller. + */ dev_kfree_skb_any(skb); - skb = skb2; - if (!skb) - return NULL; + return NULL; }
if (csum) {