On 6/27/23 16:43, 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>
>
> ---
Thanks, applied to drm-misc-next.
Noralf.
> 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/gpu/drm/gud/gud_pipe.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff -u -p a/drivers/gpu/drm/gud/gud_pipe.c b/drivers/gpu/drm/gud/gud_pipe.c
> --- a/drivers/gpu/drm/gud/gud_pipe.c
> +++ b/drivers/gpu/drm/gud/gud_pipe.c
> @@ -390,7 +390,7 @@ static int gud_fb_queue_damage(struct gu
> mutex_lock(&gdrm->damage_lock);
>
> if (!gdrm->shadow_buf) {
> - gdrm->shadow_buf = vzalloc(fb->pitches[0] * fb->height);
> + gdrm->shadow_buf = vcalloc(fb->pitches[0], fb->height);
> if (!gdrm->shadow_buf) {
> mutex_unlock(&gdrm->damage_lock);
> return -ENOMEM;
>
