Re: [PATCH] drm/amdkfd: Replace kmalloc + copy_from_user with memdup_user

[Alex Deucher]

Applied.  Thanks!

Alex

On Tue, Sep 9, 2025 at 11:29 AM Thorsten Blum <thorsten.blum@xxxxxxxxx> wrote:
>
> Replace kmalloc() followed by copy_from_user() with memdup_user() to
> improve and simplify kfd_criu_restore_queue().
>
> No functional changes intended.
>
> Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxx>
> ---
>  .../amd/amdkfd/kfd_process_queue_manager.c    | 22 +++++--------------
>  1 file changed, 6 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c
> index 7fbb5c274ccc..70c17a12cadf 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c
> @@ -1004,13 +1004,9 @@ int kfd_criu_restore_queue(struct kfd_process *p,
>         if (*priv_data_offset + sizeof(*q_data) > max_priv_data_size)
>                 return -EINVAL;
>
> -       q_data = kmalloc(sizeof(*q_data), GFP_KERNEL);
> -       if (!q_data)
> -               return -ENOMEM;
> -
> -       ret = copy_from_user(q_data, user_priv_ptr + *priv_data_offset, sizeof(*q_data));
> -       if (ret) {
> -               ret = -EFAULT;
> +       q_data = memdup_user(user_priv_ptr + *priv_data_offset, sizeof(*q_data));
> +       if (IS_ERR(q_data)) {
> +               ret = PTR_ERR(q_data);
>                 goto exit;
>         }
>
> @@ -1022,15 +1018,9 @@ int kfd_criu_restore_queue(struct kfd_process *p,
>                 goto exit;
>         }
>
> -       q_extra_data = kmalloc(q_extra_data_size, GFP_KERNEL);
> -       if (!q_extra_data) {
> -               ret = -ENOMEM;
> -               goto exit;
> -       }
> -
> -       ret = copy_from_user(q_extra_data, user_priv_ptr + *priv_data_offset, q_extra_data_size);
> -       if (ret) {
> -               ret = -EFAULT;
> +       q_extra_data = memdup_user(user_priv_ptr + *priv_data_offset, q_extra_data_size);
> +       if (IS_ERR(q_extra_data)) {
> +               ret = PTR_ERR(q_extra_data);
>                 goto exit;
>         }
>
> --
> 2.51.0
>