Re: [PATCH net-next] ieee802154: ca8210: remove a dead branch

[David Miller]

From: YueHaibing <yuehaibing@xxxxxxxxxx>
Date: Mon, 10 Dec 2018 19:34:43 +0800

> Fix follwing gcc warning:
> 
> drivers/net/ieee802154/ca8210.c:730:10: warning:
>  comparison is always false due to limited range of data type [-Wtype-limits]
> 
> the variable 'len' is of type u8 and cannot greater than
> CA8210_SPI_BUF_SIZE , which is 256.
> 
> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>

Then bug is the variable type here.

We are reading a u8 from buf[], then adding 2, which can overflow.

'len' should be an unsigned int or similar.