Re: [patch] [media] mceusb: move check earlier to make smatch happy

["David Härdeman" <david@hardeman.nu>]

On Tue, Feb 12, 2013 at 03:22:08PM +0300, Dan Carpenter wrote:
>Smatch complains that "cmdbuf[cmdcount - length]" might go past the end
>of the array.  It's an easy warning to silence by moving the limit
>check earlier.
>
>Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Looks ok. I'll leave the signing off to Jarod though. I've just dabbled
in the driver but I'm not the maintainer.

>diff --git a/drivers/media/rc/mceusb.c b/drivers/media/rc/mceusb.c
>index bdd1ed8..5b5b6e6 100644
>--- a/drivers/media/rc/mceusb.c
>+++ b/drivers/media/rc/mceusb.c
>@@ -828,16 +828,16 @@ static int mceusb_tx_ir(struct rc_dev *dev, unsigned *txbuf, unsigned count)
> 			 (txbuf[i] -= MCE_MAX_PULSE_LENGTH));
> 	}
> 
>-	/* Fix packet length in last header */
>-	length = cmdcount % MCE_CODE_LENGTH;
>-	cmdbuf[cmdcount - length] -= MCE_CODE_LENGTH - length;
>-
> 	/* Check if we have room for the empty packet at the end */
> 	if (cmdcount >= MCE_CMDBUF_SIZE) {
> 		ret = -EINVAL;
> 		goto out;
> 	}
> 
>+	/* Fix packet length in last header */
>+	length = cmdcount % MCE_CODE_LENGTH;
>+	cmdbuf[cmdcount - length] -= MCE_CODE_LENGTH - length;
>+
> 	/* All mce commands end with an empty packet (0x80) */
> 	cmdbuf[cmdcount++] = MCE_IRDATA_TRAILER;
> 
>

-- 
David Härdeman