[PATCH 0/7] fix possible object reference leaks in drivers/gpu

[PATCH 0/7] fix possible object reference leaks in drivers/gpu

[Wen Yang]

The call to of_get_cpu_node/of_find_compatible_node/of_parse_phandle...
returns a node pointer with refcount incremented thus it must be
explicitly decremented after the last usage.

This patch series fix those possible object reference leaks in drivers/gpu.

Wen Yang (7):
  drm/mediatek: fix possible object reference leak
  drm/meson: fix possible object reference leak
  drm/msm: a5xx: fix possible object reference leak
  drm/omap: fix possible object reference leak
  drm/pl111: fix possible object reference leak
  drm: rcar-du: fix possible object reference leak
  drm/tegra: fix possible object reference leak

 drivers/gpu/drm/mediatek/mtk_hdmi.c             |  1 +
 drivers/gpu/drm/meson/meson_dw_hdmi.c           |  7 ++-----
 drivers/gpu/drm/msm/adreno/a5xx_gpu.c           | 10 ++++++----
 drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c |  5 ++++-
 drivers/gpu/drm/pl111/pl111_versatile.c         |  4 ++++
 drivers/gpu/drm/rcar-du/rcar_du_of.c            |  2 ++
 drivers/gpu/drm/tegra/output.c                  |  2 ++
 drivers/gpu/drm/tegra/rgb.c                     |  8 ++++++--
 8 files changed, 27 insertions(+), 12 deletions(-)

-- 
2.9.5

[PATCH 1/7] drm/mediatek: fix possible object reference leak

[Wen Yang]

The call to of_parse_phandle returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
drivers/gpu/drm/mediatek/mtk_hdmi.c:1521:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 1509, but without a corresponding object release within this function.
drivers/gpu/drm/mediatek/mtk_hdmi.c:1524:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 1509, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: CK Hu <ck.hu@mediatek.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/gpu/drm/mediatek/mtk_hdmi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
index 915cc84..ed10f4d 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
@@ -1516,6 +1516,7 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
 	of_node_put(remote);
 
 	hdmi->ddc_adpt = of_find_i2c_adapter_by_node(i2c_np);
+	of_node_put(i2c_np);
 	if (!hdmi->ddc_adpt) {
 		dev_err(dev, "Failed to get ddc i2c adapter by node\n");
 		return -EINVAL;
-- 
2.9.5

[PATCH 2/7] drm/meson: fix possible object reference leak

[Wen Yang]

The call to of_graph_get_remote_port returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
drivers/gpu/drm/meson/meson_dw_hdmi.c:725:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 722, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org (open list)
---
 drivers/gpu/drm/meson/meson_dw_hdmi.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
index 563953e..109a933 100644
--- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
+++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
@@ -720,13 +720,10 @@ static bool meson_hdmi_connector_is_available(struct device *dev)
 
 	/* If the endpoint node exists, consider it enabled */
 	remote = of_graph_get_remote_port(ep);
-	if (remote) {
-		of_node_put(ep);
-		return true;
-	}
-
 	of_node_put(ep);
 	of_node_put(remote);
+	if (remote)
+		return true;
 
 	return false;
 }
-- 
2.9.5

[PATCH 3/7] drm/msm: a5xx: fix possible object reference leak

[Wen Yang]

The call to of_get_child_by_name returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
drivers/gpu/drm/msm/adreno/a5xx_gpu.c:57:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 47, but without a corresponding object release within this function.
drivers/gpu/drm/msm/adreno/a5xx_gpu.c:66:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 47, but without a corresponding object release within this function.
drivers/gpu/drm/msm/adreno/a5xx_gpu.c:118:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 47, but without a corresponding object release within this function.
drivers/gpu/drm/msm/adreno/a5xx_gpu.c:57:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 51, but without a corresponding object release within this function.
drivers/gpu/drm/msm/adreno/a5xx_gpu.c:66:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 51, but without a corresponding object release within this function.
drivers/gpu/drm/msm/adreno/a5xx_gpu.c:118:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 51, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jordan Crouse <jcrouse@codeaurora.org>
Cc: Mamta Shukla <mamtashukla555@gmail.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Sharat Masetty <smasetty@codeaurora.org>
Cc: linux-arm-msm@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: freedreno@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org (open list)
---
 drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
index d5f5e56..270da14 100644
--- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
@@ -34,7 +34,7 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname)
 {
 	struct device *dev = &gpu->pdev->dev;
 	const struct firmware *fw;
-	struct device_node *np;
+	struct device_node *np, *mem_np;
 	struct resource r;
 	phys_addr_t mem_phys;
 	ssize_t mem_size;
@@ -48,11 +48,13 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname)
 	if (!np)
 		return -ENODEV;
 
-	np = of_parse_phandle(np, "memory-region", 0);
-	if (!np)
+	mem_np = of_parse_phandle(np, "memory-region", 0);
+	of_node_put(np);
+	if (!mem_np)
 		return -EINVAL;
 
-	ret = of_address_to_resource(np, 0, &r);
+	ret = of_address_to_resource(mem_np, 0, &r);
+	of_node_put(mem_np);
 	if (ret)
 		return ret;
 
-- 
2.9.5

[PATCH 4/7] drm/omap: fix possible object reference leak

[Wen Yang]

The call to of_find_matching_node returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c:212:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 209, but without a corresponding object release within this function.
drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c:237:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 209, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sebastian Reichel <sebastian.reichel@collabora.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
index 2b41c75..60067e8 100644
--- a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
+++ b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
@@ -208,8 +208,10 @@ static int __init omapdss_boot_init(void)
 
 	dss = of_find_matching_node(NULL, omapdss_of_match);
 
-	if (dss == NULL || !of_device_is_available(dss))
+	if (dss == NULL || !of_device_is_available(dss)) {
+		of_node_put(dss);
 		return 0;
+	}
 
 	omapdss_walk_device(dss, true);
 
@@ -234,6 +236,7 @@ static int __init omapdss_boot_init(void)
 		kfree(n);
 	}
 
+	of_node_put(dss);
 	return 0;
 }
 
-- 
2.9.5

[PATCH 5/7] drm/pl111: fix possible object reference leak

[Wen Yang]

The call to of_find_matching_node_and_match returns a node pointer with
refcount incremented thus it must be explicitly decremented after the
last usage.

Detected by coccinelle with the following warnings:
drivers/gpu/drm/pl111/pl111_versatile.c:333:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 317, but without a corresponding object release within this function.
drivers/gpu/drm/pl111/pl111_versatile.c:340:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 317, but without a corresponding object release within this function.
drivers/gpu/drm/pl111/pl111_versatile.c:346:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 317, but without a corresponding object release within this function.
drivers/gpu/drm/pl111/pl111_versatile.c:354:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 317, but without a corresponding object release within this function.
drivers/gpu/drm/pl111/pl111_versatile.c:395:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 317, but without a corresponding object release within this function.
drivers/gpu/drm/pl111/pl111_versatile.c:402:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 317, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: Eric Anholt <eric@anholt.net> (supporter:DRM DRIVER FOR ARM PL111 CLCD)
Cc: David Airlie <airlied@linux.ie> (maintainer:DRM DRIVERS)
Cc: Daniel Vetter <daniel@ffwll.ch> (maintainer:DRM DRIVERS)
Cc: dri-devel@lists.freedesktop.org (open list:DRM DRIVERS)
Cc: linux-kernel@vger.kernel.org (open list)
---
 drivers/gpu/drm/pl111/pl111_versatile.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/pl111/pl111_versatile.c b/drivers/gpu/drm/pl111/pl111_versatile.c
index b9baefd..1c318ad 100644
--- a/drivers/gpu/drm/pl111/pl111_versatile.c
+++ b/drivers/gpu/drm/pl111/pl111_versatile.c
@@ -330,6 +330,7 @@ int pl111_versatile_init(struct device *dev, struct pl111_drm_dev_private *priv)
 		ret = vexpress_muxfpga_init();
 		if (ret) {
 			dev_err(dev, "unable to initialize muxfpga driver\n");
+			of_node_put(np);
 			return ret;
 		}
 
@@ -337,17 +338,20 @@ int pl111_versatile_init(struct device *dev, struct pl111_drm_dev_private *priv)
 		pdev = of_find_device_by_node(np);
 		if (!pdev) {
 			dev_err(dev, "can't find the sysreg device, deferring\n");
+			of_node_put(np);
 			return -EPROBE_DEFER;
 		}
 		map = dev_get_drvdata(&pdev->dev);
 		if (!map) {
 			dev_err(dev, "sysreg has not yet probed\n");
 			platform_device_put(pdev);
+			of_node_put(np);
 			return -EPROBE_DEFER;
 		}
 	} else {
 		map = syscon_node_to_regmap(np);
 	}
+	of_node_put(np);
 
 	if (IS_ERR(map)) {
 		dev_err(dev, "no Versatile syscon regmap\n");
-- 
2.9.5

[PATCH 6/7] drm: rcar-du: fix possible object reference leak

[Wen Yang]

The call to of_get_parent returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
drivers/gpu/drm/rcar-du/rcar_du_of.c:235:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 216, but without a corresponding object release within this function.
drivers/gpu/drm/rcar-du/rcar_du_of.c:236:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 209, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org (open list)
---
 drivers/gpu/drm/rcar-du/rcar_du_of.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of.c b/drivers/gpu/drm/rcar-du/rcar_du_of.c
index afef696..30bceca 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_of.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_of.c
@@ -232,6 +232,8 @@ static void __init rcar_du_of_lvds_patch(const struct of_device_id *of_ids)
 	lvds_node = of_find_compatible_node(NULL, NULL, compatible);
 	if (lvds_node) {
 		of_node_put(lvds_node);
+		of_node_put(soc_node);
+		of_node_put(du_node);
 		return;
 	}
 
-- 
2.9.5

[PATCH 7/7] drm/tegra: fix possible object reference leak

[Wen Yang]

The call to  of_get_child_by_name returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
./drivers/gpu/drm/tegra/rgb.c:225:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 223, but without a corresponding object release within this function.
./drivers/gpu/drm/tegra/rgb.c:229:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 223, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-tegra@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/gpu/drm/tegra/output.c | 2 ++
 drivers/gpu/drm/tegra/rgb.c    | 8 ++++++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c
index 9c2b9da..78553d7 100644
--- a/drivers/gpu/drm/tegra/output.c
+++ b/drivers/gpu/drm/tegra/output.c
@@ -193,6 +193,8 @@ void tegra_output_remove(struct tegra_output *output)
 
 	if (output->ddc)
 		put_device(&output->ddc->dev);
+	if (output->of_node)
+		of_node_put(output->of_node);
 }
 
 int tegra_output_init(struct drm_device *drm, struct tegra_output *output)
diff --git a/drivers/gpu/drm/tegra/rgb.c b/drivers/gpu/drm/tegra/rgb.c
index 28a78d3..ad683a2 100644
--- a/drivers/gpu/drm/tegra/rgb.c
+++ b/drivers/gpu/drm/tegra/rgb.c
@@ -221,12 +221,16 @@ 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))
+	if (!np || !of_device_is_available(np)) {
+		of_node_put(np);
 		return -ENODEV;
+	}
 
 	rgb = devm_kzalloc(dc->dev, sizeof(*rgb), GFP_KERNEL);
-	if (!rgb)
+	if (!rgb) {
+		of_node_put(np);
 		return -ENOMEM;
+	}
 
 	rgb->output.dev = dc->dev;
 	rgb->output.of_node = np;
-- 
2.9.5

Re: [PATCH 4/7] drm/omap: fix possible object reference leak

[Laurent Pinchart]

Hello Wen,

Thank you for the patch.

On Thu, Apr 04, 2019 at 12:04:12AM +0800, Wen Yang wrote:
> The call to of_find_matching_node returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
> 
> Detected by coccinelle with the following warnings:
> drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c:212:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 209, but without a corresponding object release within this function.
> drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c:237:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 209, but without a corresponding object release within this function.
> 
> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Sebastian Reichel <sebastian.reichel@collabora.com>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: dri-devel@lists.freedesktop.org
> Cc: linux-kernel@vger.kernel.org

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Would you like to get the series merged in one go, or individual patches
picked by the respective maintainer ?

> ---
>  drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> index 2b41c75..60067e8 100644
> --- a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> +++ b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> @@ -208,8 +208,10 @@ static int __init omapdss_boot_init(void)
>  
>  	dss = of_find_matching_node(NULL, omapdss_of_match);
>  
> -	if (dss == NULL || !of_device_is_available(dss))
> +	if (dss == NULL || !of_device_is_available(dss)) {
> +		of_node_put(dss);
>  		return 0;
> +	}
>  
>  	omapdss_walk_device(dss, true);
>  
> @@ -234,6 +236,7 @@ static int __init omapdss_boot_init(void)
>  		kfree(n);
>  	}
>  
> +	of_node_put(dss);
>  	return 0;
>  }
>  

-- 
Regards,

Laurent Pinchart

Re: [PATCH 6/7] drm: rcar-du: fix possible object reference leak

[Laurent Pinchart]

Hi Wen,

Thank you for the patch.

On Thu, Apr 04, 2019 at 12:04:14AM +0800, Wen Yang wrote:
> The call to of_get_parent returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
> 
> Detected by coccinelle with the following warnings:
> drivers/gpu/drm/rcar-du/rcar_du_of.c:235:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 216, but without a corresponding object release within this function.
> drivers/gpu/drm/rcar-du/rcar_du_of.c:236:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 209, but without a corresponding object release within this function.
> 
> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: dri-devel@lists.freedesktop.org
> Cc: linux-renesas-soc@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org (open list)
> ---
>  drivers/gpu/drm/rcar-du/rcar_du_of.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of.c b/drivers/gpu/drm/rcar-du/rcar_du_of.c
> index afef696..30bceca 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_du_of.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_du_of.c
> @@ -232,6 +232,8 @@ static void __init rcar_du_of_lvds_patch(const struct of_device_id *of_ids)
>  	lvds_node = of_find_compatible_node(NULL, NULL, compatible);
>  	if (lvds_node) {
>  		of_node_put(lvds_node);
> +		of_node_put(soc_node);
> +		of_node_put(du_node);
>  		return;

Wouldn't it be simpler to just turn the return into a goto done ?

>  	}
>  

-- 
Regards,

Laurent Pinchart

Re: [PATCH 5/7] drm/pl111: fix possible object reference leak

[Eric Anholt]

[-- Attachment #1: Type: text/plain, Size: 237 bytes --]

Wen Yang <wen.yang99@zte.com.cn> writes:

> The call to of_find_matching_node_and_match returns a node pointer with
> refcount incremented thus it must be explicitly decremented after the
> last usage.

Pushed to drm-misc-next.  Thanks!

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Re: [PATCH 2/7] drm/meson: fix possible object reference leak

[Markus Elfring]

> @@ -720,13 +720,10 @@ static bool meson_hdmi_connector_is_available(struct device *dev)
>
>  	/* If the endpoint node exists, consider it enabled */
>  	remote = of_graph_get_remote_port(ep);
> -	if (remote) {
> -		of_node_put(ep);
> -		return true;
> -	}
> -
>  	of_node_put(ep);
>  	of_node_put(remote);

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/gpu/drm/meson/meson_dw_hdmi.c?id=61de49cb596710b918f7a80839f0b6de2017bc32#n712

Can the order of these put calls matter (because of processor caches)?


> +	if (remote)
> +		return true;
>
>  	return false;

Would the use of a ternary operator be more succinct here?

+	return remote ? true : false;

Regards,
Markus

Re: [PATCH 4/7] drm/omap: fix possible object reference leak

[Markus Elfring]

> @@ -208,8 +208,10 @@  static int __init omapdss_boot_init(void)
>
>  	dss = of_find_matching_node(NULL, omapdss_of_match);
>
> -	if (dss == NULL || !of_device_is_available(dss))
> +	if (dss == NULL || !of_device_is_available(dss)) {
> +		of_node_put(dss);
>  		return 0;
> +	}

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c?id=61de49cb596710b918f7a80839f0b6de2017bc32#n203

Can it be nicer to add a jump target here?

+	if (!dss || !of_device_is_available(dss))
-		return 0;
+		goto put_node;


>
>  	omapdss_walk_device(dss, true);
>
> @@ -234,6 +236,7 @@  static int __init omapdss_boot_init(void)
>  		kfree(n);
>  	}
>

+put_node:

> +	of_node_put(dss);
>  	return 0;
>  }


Regards,
Markus

Re: [PATCH 5/7] drm/pl111: fix possible object reference leak

[Markus Elfring]

> @@ -337,17 +338,20 @@ int pl111_versatile_init(struct device *dev, struct pl111_drm_dev_private *priv)
>  		pdev = of_find_device_by_node(np);
>  		if (!pdev) {
>  			dev_err(dev, "can't find the sysreg device, deferring\n");
> +			of_node_put(np);
>  			return -EPROBE_DEFER;
>  		}
>  		map = dev_get_drvdata(&pdev->dev);
>  		if (!map) {
>  			dev_err(dev, "sysreg has not yet probed\n");
>  			platform_device_put(pdev);
> +			of_node_put(np);
>  			return -EPROBE_DEFER;
>  		}

How do you think about to move duplicate statements to an additional
jump target for the desired exception handling?

Regards,
Markus

Re: [PATCH 1/7] drm/mediatek: fix possible object reference leak

[CK Hu]

Hi, Wen:

On Thu, 2019-04-04 at 00:04 +0800, Wen Yang wrote:
> The call to of_parse_phandle returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
> 
> Detected by coccinelle with the following warnings:
> drivers/gpu/drm/mediatek/mtk_hdmi.c:1521:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 1509, but without a corresponding object release within this function.
> drivers/gpu/drm/mediatek/mtk_hdmi.c:1524:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 1509, but without a corresponding object release within this function.

For this patch, applied to mediatek-drm-fixes-5.1 [1], thanks.

[1]
https://github.com/ckhu-mediatek/linux.git-tags/commits/mediatek-drm-fixes-5.1

Regards,
CK

> 
> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
> Cc: CK Hu <ck.hu@mediatek.com>
> Cc: Philipp Zabel <p.zabel@pengutronix.de>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Matthias Brugger <matthias.bgg@gmail.com>
> Cc: dri-devel@lists.freedesktop.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-mediatek@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  drivers/gpu/drm/mediatek/mtk_hdmi.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> index 915cc84..ed10f4d 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> @@ -1516,6 +1516,7 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
>  	of_node_put(remote);
>  
>  	hdmi->ddc_adpt = of_find_i2c_adapter_by_node(i2c_np);
> +	of_node_put(i2c_np);
>  	if (!hdmi->ddc_adpt) {
>  		dev_err(dev, "Failed to get ddc i2c adapter by node\n");
>  		return -EINVAL;

Re: [PATCH 3/7] drm/msm: a5xx: fix possible object reference leak

[Jordan Crouse]

On Thu, Apr 04, 2019 at 12:04:11AM +0800, Wen Yang wrote:
> The call to of_get_child_by_name returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
> 
> Detected by coccinelle with the following warnings:
> drivers/gpu/drm/msm/adreno/a5xx_gpu.c:57:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 47, but without a corresponding object release within this function.
> drivers/gpu/drm/msm/adreno/a5xx_gpu.c:66:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 47, but without a corresponding object release within this function.
> drivers/gpu/drm/msm/adreno/a5xx_gpu.c:118:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 47, but without a corresponding object release within this function.
> drivers/gpu/drm/msm/adreno/a5xx_gpu.c:57:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 51, but without a corresponding object release within this function.
> drivers/gpu/drm/msm/adreno/a5xx_gpu.c:66:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 51, but without a corresponding object release within this function.
> drivers/gpu/drm/msm/adreno/a5xx_gpu.c:118:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 51, but without a corresponding object release within this function.
> 
> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
> Cc: Rob Clark <robdclark@gmail.com>
> Cc: Sean Paul <sean@poorly.run>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Jordan Crouse <jcrouse@codeaurora.org>
> Cc: Mamta Shukla <mamtashukla555@gmail.com>
> Cc: Thomas Zimmermann <tzimmermann@suse.de>
> Cc: Sharat Masetty <smasetty@codeaurora.org>
> Cc: linux-arm-msm@vger.kernel.org
> Cc: dri-devel@lists.freedesktop.org
> Cc: freedreno@lists.freedesktop.org
> Cc: linux-kernel@vger.kernel.org (open list)


Sorry for the delay. This looks right to me and possibly appropriate for stable
as well.

Reviewed-by: Jordan Crouse <jcrouse@codeaurora.org>

> ---
>  drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> index d5f5e56..270da14 100644
> --- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> +++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> @@ -34,7 +34,7 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname)
>  {
>  	struct device *dev = &gpu->pdev->dev;
>  	const struct firmware *fw;
> -	struct device_node *np;
> +	struct device_node *np, *mem_np;
>  	struct resource r;
>  	phys_addr_t mem_phys;
>  	ssize_t mem_size;
> @@ -48,11 +48,13 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname)
>  	if (!np)
>  		return -ENODEV;
>  
> -	np = of_parse_phandle(np, "memory-region", 0);
> -	if (!np)
> +	mem_np = of_parse_phandle(np, "memory-region", 0);
> +	of_node_put(np);
> +	if (!mem_np)
>  		return -EINVAL;
>  
> -	ret = of_address_to_resource(np, 0, &r);
> +	ret = of_address_to_resource(mem_np, 0, &r);
> +	of_node_put(mem_np);
>  	if (ret)
>  		return ret;
>  
> -- 
> 2.9.5
> 

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