Re: staging: iio: accel: Use __be16 instead of u16

[Dan Carpenter <dan.carpenter@oracle.com>]

Ping!

regards,
dan carpenter

On Wed, Jul 15, 2015 at 10:36:51PM +0300, Dan Carpenter wrote:
> Hello Aybuke Ozdemir,
> 
> The patch 03c6eaa37ad7: "staging: iio: accel: Use __be16 instead of
> u16" from Sep 28, 2014, leads to the following static checker warning:
> 
> 	drivers/staging/iio/accel/sca3000_ring.c:120 sca3000_read_first_n_hw_rb()
> 	warn: potential pointer math issue ('rx' is a 16 bit pointer)
> 
> drivers/staging/iio/accel/sca3000_ring.c
>    107           */
>    108          if (count > num_available * bytes_per_sample)
>    109                  num_read = num_available*bytes_per_sample;
>    110          else
>    111                  num_read = count;
>    112  
>    113          ret = sca3000_read_data(st,
>    114                                  SCA3000_REG_ADDR_RING_OUT,
>    115                                  &rx, num_read);
>    116          if (ret)
>    117                  goto error_ret;
>    118  
>    119          for (i = 0; i < num_read; i++)
>    120                  *(((u16 *)rx) + i) = be16_to_cpup((__be16 *)rx + i);
>                           ^^^^^^^^^^^^^^^
> 
> We're writing beyond the end of the array here because of the pointer
> math issue.  The fix is probably to say:
> 
> 		for (i = 0; i < num_read / sizeof(u16); i++)
> 			*(((u16 *)rx) + i) = be16_to_cpup((__be16 *)rx + i);
> 
>    121  
>    122          if (copy_to_user(buf, rx, num_read))
>    123                  ret = -EFAULT;
> 
> 
> regards,
> dan carpenter