The following patchset fix two refcount leak bugs.
The cause of the bugs are missing of_node_put()
after of_graph_get_remote_node().
changes in v2:
- patch#2:Fixed patch in meson_encoder_hdmi_init, call of_node_put()
after of_find_device_by_node() and error paths before that.
noted by Martin Blumenstingl <[email protected]>
(patch#1: no changes since v1)
v1 link:
patch#1: https://lore.kernel.org/r/[email protected]/
patch#2: https://lore.kernel.org/r/[email protected]/
Miaoqian Lin (2):
drm/meson: encoder_cvbs: Fix refcount leak in meson_encoder_cvbs_init
drm/meson: encoder_hdmi: Fix refcount leak in meson_encoder_hdmi_init
drivers/gpu/drm/meson/meson_encoder_cvbs.c | 1 +
drivers/gpu/drm/meson/meson_encoder_hdmi.c | 15 +++++++++++----
2 files changed, 12 insertions(+), 4 deletions(-)
--
2.25.1
of_graph_get_remote_node() returns remote device nodepointer with
refcount incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.
Fixes: e67f6037ae1b ("drm/meson: split out encoder from meson_dw_hdmi")
Signed-off-by: Miaoqian Lin <[email protected]>
---
changes in v2:
- call of_node_put() after of_find_device_by_node() and error paths
before of_find_device_by_node();
---
drivers/gpu/drm/meson/meson_encoder_hdmi.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/meson/meson_encoder_hdmi.c b/drivers/gpu/drm/meson/meson_encoder_hdmi.c
index 5e306de6f485..0d532e8e8cca 100644
--- a/drivers/gpu/drm/meson/meson_encoder_hdmi.c
+++ b/drivers/gpu/drm/meson/meson_encoder_hdmi.c
@@ -365,7 +365,8 @@ int meson_encoder_hdmi_init(struct meson_drm *priv)
meson_encoder_hdmi->next_bridge = of_drm_find_bridge(remote);
if (!meson_encoder_hdmi->next_bridge) {
dev_err(priv->dev, "Failed to find HDMI transceiver bridge\n");
- return -EPROBE_DEFER;
+ ret = -EPROBE_DEFER;
+ goto err_put_node;
}
/* HDMI Encoder Bridge */
@@ -383,7 +384,7 @@ int meson_encoder_hdmi_init(struct meson_drm *priv)
DRM_MODE_ENCODER_TMDS);
if (ret) {
dev_err(priv->dev, "Failed to init HDMI encoder: %d\n", ret);
- return ret;
+ goto err_put_node;
}
meson_encoder_hdmi->encoder.possible_crtcs = BIT(0);
@@ -393,7 +394,7 @@ int meson_encoder_hdmi_init(struct meson_drm *priv)
DRM_BRIDGE_ATTACH_NO_CONNECTOR);
if (ret) {
dev_err(priv->dev, "Failed to attach bridge: %d\n", ret);
- return ret;
+ goto err_put_node;
}
/* Initialize & attach Bridge Connector */
@@ -401,7 +402,8 @@ int meson_encoder_hdmi_init(struct meson_drm *priv)
&meson_encoder_hdmi->encoder);
if (IS_ERR(meson_encoder_hdmi->connector)) {
dev_err(priv->dev, "Unable to create HDMI bridge connector\n");
- return PTR_ERR(meson_encoder_hdmi->connector);
+ ret = PTR_ERR(meson_encoder_hdmi->connector);
+ goto err_put_node;
}
drm_connector_attach_encoder(meson_encoder_hdmi->connector,
&meson_encoder_hdmi->encoder);
@@ -428,6 +430,7 @@ int meson_encoder_hdmi_init(struct meson_drm *priv)
meson_encoder_hdmi->connector->ycbcr_420_allowed = true;
pdev = of_find_device_by_node(remote);
+ of_node_put(remote);
if (pdev) {
struct cec_connector_info conn_info;
struct cec_notifier *notifier;
@@ -444,4 +447,8 @@ int meson_encoder_hdmi_init(struct meson_drm *priv)
dev_dbg(priv->dev, "HDMI encoder initialized\n");
return 0;
+
+err_put_node:
+ of_node_put(remote);
+ return ret;
}
--
2.25.1
Hello,
thank you for working on this!
On Wed, Jun 1, 2022 at 5:40 AM Miaoqian Lin <[email protected]> wrote:
>
> of_graph_get_remote_node() returns remote device nodepointer with
> refcount incremented, we should use of_node_put() on it when done.
> Add missing of_node_put() to avoid refcount leak.
>
> Fixes: e67f6037ae1b ("drm/meson: split out encoder from meson_dw_hdmi")
> Signed-off-by: Miaoqian Lin <[email protected]>
Reviewed-by: Martin Blumenstingl <[email protected]>
Note to self: at first I thought the following code needs to be changed as well:
notifier = cec_notifier_conn_register(&pdev->dev, NULL, &conn_info);
if (!notifier)
return -ENOMEM;
But a few lines before this we already have:
of_node_put(remote);
Meaning: this patch is fine as is.
Best regards,
Martin
Hi,
On Wed, 1 Jun 2022 07:39:25 +0400, Miaoqian Lin wrote:
> The following patchset fix two refcount leak bugs.
> The cause of the bugs are missing of_node_put()
> after of_graph_get_remote_node().
>
> changes in v2:
> - patch#2:Fixed patch in meson_encoder_hdmi_init, call of_node_put()
> after of_find_device_by_node() and error paths before that.
> noted by Martin Blumenstingl <[email protected]>
>
> [...]
Thanks, Applied to https://anongit.freedesktop.org/git/drm/drm-misc.git (drm-misc-next)
[1/2] drm/meson: encoder_cvbs: Fix refcount leak in meson_encoder_cvbs_init
https://cgit.freedesktop.org/drm/drm-misc/commit/?id=7d255ddbbf679aa47e041cbf68520fd985ed2279
[2/2] drm/meson: encoder_hdmi: Fix refcount leak in meson_encoder_hdmi_init
https://cgit.freedesktop.org/drm/drm-misc/commit/?id=d82a5a4aae9d0203234737caed1bf470aa317568
--
Neil