Re: [PATCH v2 10/24] bus: mhi: host: use vmalloc_array and vcalloc

[Manivannan Sadhasivam]

On Tue, Jun 27, 2023 at 04:43:25PM +0200, Julia Lawall wrote:
> Use vmalloc_array and vcalloc to protect against
> multiplication overflows.
> 
> The changes were done using the following Coccinelle
> semantic patch:
> 
> // <smpl>
> @initialize:ocaml@
> @@
> 
> let rename alloc =
>   match alloc with
>     "vmalloc" -> "vmalloc_array"
>   | "vzalloc" -> "vcalloc"
>   | _ -> failwith "unknown"
> 
> @@
>     size_t e1,e2;
>     constant C1, C2;
>     expression E1, E2, COUNT, x1, x2, x3;
>     typedef u8;
>     typedef __u8;
>     type t = {u8,__u8,char,unsigned char};
>     identifier alloc = {vmalloc,vzalloc};
>     fresh identifier realloc = script:ocaml(alloc) { rename alloc };
> @@
> 
> (
>       alloc(x1*x2*x3)
> |
>       alloc(C1 * C2)
> |
>       alloc((sizeof(t)) * (COUNT), ...)
> |
> -     alloc((e1) * (e2))
> +     realloc(e1, e2)
> |
> -     alloc((e1) * (COUNT))
> +     realloc(COUNT, e1)
> |
> -     alloc((E1) * (E2))
> +     realloc(E1, E2)
> )
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxxx>

Applied to mhi-next!

- Mani

> 
> ---
> v2: Use vmalloc_array and vcalloc instead of array_size.
> This also leaves a multiplication of a constant by a sizeof
> as is.  Two patches are thus dropped from the series.
> 
>  drivers/bus/mhi/host/init.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff -u -p a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
> --- a/drivers/bus/mhi/host/init.c
> +++ b/drivers/bus/mhi/host/init.c
> @@ -759,7 +759,7 @@ static int parse_ch_cfg(struct mhi_contr
>  	 * so to avoid any memory possible allocation failures, vzalloc is
>  	 * used here
>  	 */
> -	mhi_cntrl->mhi_chan = vzalloc(mhi_cntrl->max_chan *
> +	mhi_cntrl->mhi_chan = vcalloc(mhi_cntrl->max_chan,
>  				      sizeof(*mhi_cntrl->mhi_chan));
>  	if (!mhi_cntrl->mhi_chan)
>  		return -ENOMEM;
> 

-- 
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