Re: [ 04/21] target/pscsi: Fix page increment

[Ben Hutchings]

On Tue, 2013-03-12 at 15:44 -0700, Greg Kroah-Hartman wrote:
> 3.0-stable review patch.  If anyone has any objections, please let me know.
> 
> ------------------
> 
> From: Asias He <asias@xxxxxxxxxx>
> 
> commit 472b72f2db7831d7dbe22ffdff4adee3bd49b05d upstream.
> 
> The page++ is wrong. It makes bio_add_pc_page() pointing to a wrong page
> address if the 'while (len > 0 && data_len > 0) { ... }' loop is
> executed more than one once.
> 
> Signed-off-by: Asias He <asias@xxxxxxxxxx>
> Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> 
> ---
>  drivers/target/target_core_pscsi.c |    1 -
>  1 file changed, 1 deletion(-)
> 
> --- a/drivers/target/target_core_pscsi.c
> +++ b/drivers/target/target_core_pscsi.c
> @@ -1210,7 +1210,6 @@ static int __pscsi_map_task_SG(
>  				bio = NULL;
>  			}
>  
> -			page++;
>  			len -= bytes;
>  			data_len -= bytes;
>  			off = 0;

So in case a fragment crosses a page boundary, we wrap around to the
beginning of the same page?  That doesn't look right.

Ben.

-- 
Ben Hutchings
It is easier to change the specification to fit the program than vice versa.

Attachment: signature.asc
Description: This is a digitally signed message part