[PATCH v2] drm/msm/dsi: Add missing check for alloc_ordered_workqueue

[Dmitry Baryshkov]

On Mon, 9 Jan 2023 at 04:51, Jiasheng Jiang <jiasheng at iscas.ac.cn> wrote:
>
> Add check for the return value of alloc_ordered_workqueue as it may return
> NULL pointer and cause NULL pointer dereference.
> Moreover, change the "goto fail" into "return ret" and drop the "fail"
> label since they are the same.
>
> Signed-off-by: Jiasheng Jiang <jiasheng at iscas.ac.cn>
> ---
> Changelog:
>
> v1 -> v2:
>
> 1. Change the "goto fail" into "return ret" and drop the "fail" label.

These are separate changes and should come as separate patches.

> ---
>  drivers/gpu/drm/msm/dsi/dsi_host.c | 24 +++++++++++++-----------
>  1 file changed, 13 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
> index 89aadd3b3202..819f5be5fd77 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> @@ -1884,7 +1884,7 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
>         msm_host = devm_kzalloc(&pdev->dev, sizeof(*msm_host), GFP_KERNEL);
>         if (!msm_host) {
>                 ret = -ENOMEM;
> -               goto fail;
> +               return ret;
>         }
>
>         msm_host->pdev = pdev;
> @@ -1893,14 +1893,14 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
>         ret = dsi_host_parse_dt(msm_host);
>         if (ret) {
>                 pr_err("%s: failed to parse dt\n", __func__);
> -               goto fail;
> +               return ret;
>         }
>
>         msm_host->ctrl_base = msm_ioremap_size(pdev, "dsi_ctrl", &msm_host->ctrl_size);
>         if (IS_ERR(msm_host->ctrl_base)) {
>                 pr_err("%s: unable to map Dsi ctrl base\n", __func__);
>                 ret = PTR_ERR(msm_host->ctrl_base);
> -               goto fail;
> +               return ret;
>         }
>
>         pm_runtime_enable(&pdev->dev);
> @@ -1909,7 +1909,7 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
>         if (!msm_host->cfg_hnd) {
>                 ret = -EINVAL;
>                 pr_err("%s: get config failed\n", __func__);
> -               goto fail;
> +               return ret;
>         }
>         cfg = msm_host->cfg_hnd->cfg;
>
> @@ -1917,7 +1917,7 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
>         if (msm_host->id < 0) {
>                 ret = msm_host->id;
>                 pr_err("%s: unable to identify DSI host index\n", __func__);
> -               goto fail;
> +               return ret;
>         }
>
>         /* fixup base address by io offset */
> @@ -1927,19 +1927,19 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
>                                             cfg->regulator_data,
>                                             &msm_host->supplies);
>         if (ret)
> -               goto fail;
> +               return ret;
>
>         ret = dsi_clk_init(msm_host);
>         if (ret) {
>                 pr_err("%s: unable to initialize dsi clks\n", __func__);
> -               goto fail;
> +               return ret;
>         }
>
>         msm_host->rx_buf = devm_kzalloc(&pdev->dev, SZ_4K, GFP_KERNEL);
>         if (!msm_host->rx_buf) {
>                 ret = -ENOMEM;
>                 pr_err("%s: alloc rx temp buf failed\n", __func__);
> -               goto fail;
> +               return ret;
>         }
>
>         ret = devm_pm_opp_set_clkname(&pdev->dev, "byte");
> @@ -1977,15 +1977,17 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
>
>         /* setup workqueue */
>         msm_host->workqueue = alloc_ordered_workqueue("dsi_drm_work", 0);
> +       if (!msm_host->workqueue) {
> +               ret = -ENOMEM;
> +               return ret;
> +       }
> +
>         INIT_WORK(&msm_host->err_work, dsi_err_worker);
>
>         msm_dsi->id = msm_host->id;
>
>         DBG("Dsi Host %d initialized", msm_host->id);
>         return 0;
> -
> -fail:
> -       return ret;
>  }
>
>  void msm_dsi_host_destroy(struct mipi_dsi_host *host)
> --
> 2.25.1
>


-- 
With best wishes
Dmitry