Re: [PATCH v2 15/24] habanalabs: use vmalloc_array and vcalloc

[Oded Gabbay <ogabbay@kernel.org>]

On Tue, Jun 27, 2023 at 5:44 PM Julia Lawall <Julia.Lawall@inria.fr> 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@inria.fr>
>
> ---
> 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/accel/habanalabs/common/device.c     |    3 ++-
>  drivers/accel/habanalabs/common/state_dump.c |    7 ++++---
>  2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff -u -p a/drivers/accel/habanalabs/common/device.c b/drivers/accel/habanalabs/common/device.c
> --- a/drivers/accel/habanalabs/common/device.c
> +++ b/drivers/accel/habanalabs/common/device.c
> @@ -2594,7 +2594,8 @@ static void hl_capture_user_mappings(str
>          */
>         vfree(pgf_info->user_mappings);
>         pgf_info->user_mappings =
> -                       vzalloc(pgf_info->num_of_user_mappings * sizeof(struct hl_user_mapping));
> +                       vcalloc(pgf_info->num_of_user_mappings,
> +                               sizeof(struct hl_user_mapping));
>         if (!pgf_info->user_mappings) {
>                 pgf_info->num_of_user_mappings = 0;
>                 goto finish;
> diff -u -p a/drivers/accel/habanalabs/common/state_dump.c b/drivers/accel/habanalabs/common/state_dump.c
> --- a/drivers/accel/habanalabs/common/state_dump.c
> +++ b/drivers/accel/habanalabs/common/state_dump.c
> @@ -272,7 +272,8 @@ static u32 *hl_state_dump_read_sync_obje
>         base_addr = sds->props[SP_SYNC_OBJ_BASE_ADDR] +
>                         sds->props[SP_NEXT_SYNC_OBJ_ADDR] * index;
>
> -       sync_objects = vmalloc(sds->props[SP_SYNC_OBJ_AMOUNT] * sizeof(u32));
> +       sync_objects = vmalloc_array(sds->props[SP_SYNC_OBJ_AMOUNT],
> +                                    sizeof(u32));
>         if (!sync_objects)
>                 return NULL;
>
> @@ -453,8 +454,8 @@ hl_state_dump_alloc_read_sm_block_monito
>         s64 base_addr; /* Base addr can be negative */
>         int i;
>
> -       monitors = vmalloc(sds->props[SP_MONITORS_AMOUNT] *
> -                          sizeof(struct hl_mon_state_dump));
> +       monitors = vmalloc_array(sds->props[SP_MONITORS_AMOUNT],
> +                                sizeof(struct hl_mon_state_dump));
>         if (!monitors)
>                 return NULL;
>
>

Reviewed-by: Oded Gabbay <ogabbay@kernel.org>