On Fri, 2015-05-22 at 13:15 +0200, Bjørn Mork wrote:
> The tx_curr_frame_payload field is u32. When we try to calculate a
> small negative delta based on it, we end up with a positive integer
> close to 2^32 instead. So the tx_bytes pointer increases by about
> 2^32 for every transmitted frame.
>
> Fix by calculating the delta as a signed long.
Told you I hadn't tested it.
Ben.
> Cc: Ben Hutchings <ben.hutchi...@codethink.co.uk>
> Reported-by: Florian Bruhin <m...@the-compiler.org>
> Fixes: 7a1e890e2168 ("usbnet: Fix tx_bytes statistic running backward in
> cdc_ncm")
> Signed-off-by: Bjørn Mork <bj...@mork.no>
> ---
> drivers/net/usb/cdc_ncm.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
> index c3e4da9e79ca..8067b8fbb0ee 100644
> --- a/drivers/net/usb/cdc_ncm.c
> +++ b/drivers/net/usb/cdc_ncm.c
> @@ -1182,7 +1182,7 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct
> sk_buff *skb, __le32 sign)
> * payload data instead.
> */
> usbnet_set_skb_tx_stats(skb_out, n,
> - ctx->tx_curr_frame_payload - skb_out->len);
> + (long)ctx->tx_curr_frame_payload -
> skb_out->len);
>
> return skb_out;
>
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
