Re: [PATCH v2] drm/tegra: dc: rgb: Fix refcount leak in tegra_dc_rgb_probe

2022-06-03 Thread Dmitry Osipenko
On 6/3/22 16:27, Miaoqian Lin wrote:
> of_get_child_by_name() returns a node pointer with refcount
> incremented, we should use of_node_put() on it when not need anymore.
> So add of_node_put() in error paths.
> 
> Fixes: d8f4a9eda006 ("drm: Add NVIDIA Tegra20 support")
> Signed-off-by: Miaoqian Lin 
> ---
> changes in v2:
> - update Fixes tag.
> v1 Link: https://lore.kernel.org/r/20220602155615.43277-1-linmq...@gmail.com
> ---
>  drivers/gpu/drm/tegra/rgb.c | 31 +--
>  1 file changed, 21 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/tegra/rgb.c b/drivers/gpu/drm/tegra/rgb.c
> index ff8fce36d2aa..cef2b1b72385 100644
> --- a/drivers/gpu/drm/tegra/rgb.c
> +++ b/drivers/gpu/drm/tegra/rgb.c
> @@ -196,12 +196,16 @@ int tegra_dc_rgb_probe(struct tegra_dc *dc)
>   int err;
>  
>   np = of_get_child_by_name(dc->dev->of_node, "rgb");
> - if (!np || !of_device_is_available(np))
> - return -ENODEV;
> + if (!np || !of_device_is_available(np)) {
> + err = -ENODEV;
> + goto err_put_node;
> + }
>  
>   rgb = devm_kzalloc(dc->dev, sizeof(*rgb), GFP_KERNEL);
> - if (!rgb)
> - return -ENOMEM;
> + if (!rgb) {
> + err = -ENOMEM;
> + goto err_put_node;
> + }
>  
>   rgb->output.dev = dc->dev;
>   rgb->output.of_node = np;
> @@ -209,31 +213,34 @@ int tegra_dc_rgb_probe(struct tegra_dc *dc)
>  
>   err = tegra_output_probe(>output);
>   if (err < 0)
> - return err;
> + goto err_put_node;
> +
>  
>   rgb->clk = devm_clk_get(dc->dev, NULL);
>   if (IS_ERR(rgb->clk)) {
>   dev_err(dc->dev, "failed to get clock\n");
> - return PTR_ERR(rgb->clk);
> + err =  PTR_ERR(rgb->clk);
> + goto err_put_node;
>   }
>  
>   rgb->clk_parent = devm_clk_get(dc->dev, "parent");
>   if (IS_ERR(rgb->clk_parent)) {
>   dev_err(dc->dev, "failed to get parent clock\n");
> - return PTR_ERR(rgb->clk_parent);
> + err = PTR_ERR(rgb->clk_parent);
> + goto err_put_node;
>   }
>  
>   err = clk_set_parent(rgb->clk, rgb->clk_parent);
>   if (err < 0) {
>   dev_err(dc->dev, "failed to set parent clock: %d\n", err);
> - return err;
> + goto err_put_node;
>   }
>  
>   rgb->pll_d_out0 = clk_get_sys(NULL, "pll_d_out0");
>   if (IS_ERR(rgb->pll_d_out0)) {
>   err = PTR_ERR(rgb->pll_d_out0);
>   dev_err(dc->dev, "failed to get pll_d_out0: %d\n", err);
> - return err;
> + goto err_put_node;
>   }
>  
>   if (dc->soc->has_pll_d2_out0) {
> @@ -241,13 +248,17 @@ int tegra_dc_rgb_probe(struct tegra_dc *dc)
>   if (IS_ERR(rgb->pll_d2_out0)) {
>   err = PTR_ERR(rgb->pll_d2_out0);
>   dev_err(dc->dev, "failed to get pll_d2_out0: %d\n", 
> err);
> - return err;
> + goto err_put_node;
>   }
>   }
>  
>   dc->rgb = >output;
>  
>   return 0;
> +
> +err_put_node:
> + of_node_put(np);
> + return err;
>  }
>  
>  int tegra_dc_rgb_remove(struct tegra_dc *dc)

Doesn't look like the node is put on driver removal either. Hence you
should make it resource-managed.

-- 
Best regards,
Dmitry


[PATCH v2] drm/tegra: dc: rgb: Fix refcount leak in tegra_dc_rgb_probe

2022-06-03 Thread Miaoqian Lin
of_get_child_by_name() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
So add of_node_put() in error paths.

Fixes: d8f4a9eda006 ("drm: Add NVIDIA Tegra20 support")
Signed-off-by: Miaoqian Lin 
---
changes in v2:
- update Fixes tag.
v1 Link: https://lore.kernel.org/r/20220602155615.43277-1-linmq...@gmail.com
---
 drivers/gpu/drm/tegra/rgb.c | 31 +--
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/tegra/rgb.c b/drivers/gpu/drm/tegra/rgb.c
index ff8fce36d2aa..cef2b1b72385 100644
--- a/drivers/gpu/drm/tegra/rgb.c
+++ b/drivers/gpu/drm/tegra/rgb.c
@@ -196,12 +196,16 @@ int tegra_dc_rgb_probe(struct tegra_dc *dc)
int err;
 
np = of_get_child_by_name(dc->dev->of_node, "rgb");
-   if (!np || !of_device_is_available(np))
-   return -ENODEV;
+   if (!np || !of_device_is_available(np)) {
+   err = -ENODEV;
+   goto err_put_node;
+   }
 
rgb = devm_kzalloc(dc->dev, sizeof(*rgb), GFP_KERNEL);
-   if (!rgb)
-   return -ENOMEM;
+   if (!rgb) {
+   err = -ENOMEM;
+   goto err_put_node;
+   }
 
rgb->output.dev = dc->dev;
rgb->output.of_node = np;
@@ -209,31 +213,34 @@ int tegra_dc_rgb_probe(struct tegra_dc *dc)
 
err = tegra_output_probe(>output);
if (err < 0)
-   return err;
+   goto err_put_node;
+
 
rgb->clk = devm_clk_get(dc->dev, NULL);
if (IS_ERR(rgb->clk)) {
dev_err(dc->dev, "failed to get clock\n");
-   return PTR_ERR(rgb->clk);
+   err =  PTR_ERR(rgb->clk);
+   goto err_put_node;
}
 
rgb->clk_parent = devm_clk_get(dc->dev, "parent");
if (IS_ERR(rgb->clk_parent)) {
dev_err(dc->dev, "failed to get parent clock\n");
-   return PTR_ERR(rgb->clk_parent);
+   err = PTR_ERR(rgb->clk_parent);
+   goto err_put_node;
}
 
err = clk_set_parent(rgb->clk, rgb->clk_parent);
if (err < 0) {
dev_err(dc->dev, "failed to set parent clock: %d\n", err);
-   return err;
+   goto err_put_node;
}
 
rgb->pll_d_out0 = clk_get_sys(NULL, "pll_d_out0");
if (IS_ERR(rgb->pll_d_out0)) {
err = PTR_ERR(rgb->pll_d_out0);
dev_err(dc->dev, "failed to get pll_d_out0: %d\n", err);
-   return err;
+   goto err_put_node;
}
 
if (dc->soc->has_pll_d2_out0) {
@@ -241,13 +248,17 @@ int tegra_dc_rgb_probe(struct tegra_dc *dc)
if (IS_ERR(rgb->pll_d2_out0)) {
err = PTR_ERR(rgb->pll_d2_out0);
dev_err(dc->dev, "failed to get pll_d2_out0: %d\n", 
err);
-   return err;
+   goto err_put_node;
}
}
 
dc->rgb = >output;
 
return 0;
+
+err_put_node:
+   of_node_put(np);
+   return err;
 }
 
 int tegra_dc_rgb_remove(struct tegra_dc *dc)
-- 
2.25.1