net: usbnet: fix SG initialisation

Commit 60e453a940ac ("USBNET: fix handling padding packet")
added an extra SG entry in case padding is necessary, but
failed to update the initialisation of the list. This can
cause list traversal to fall off the end of the list,
resulting in an oops.

Fixes: 60e453a940ac ("USBNET: fix handling padding packet")
Reported-by: Thomas Kear <thomas@kear.co.nz>
Cc: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Tested-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 8494bb5..aba04f5 100644 (file)
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1245,7 +1245,7 @@ static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
                return -ENOMEM;
 
        urb->num_sgs = num_sgs;
-       sg_init_table(urb->sg, urb->num_sgs);
+       sg_init_table(urb->sg, urb->num_sgs + 1);
 
        sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
        total_len += skb_headlen(skb);