Hi Laurent,
Thank you for your review.
On Fri, Dec 13, 2024 at 6:33 PM Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
>
> Hi Joe,
>
> Thank you for the patch.
>
> On Fri, Dec 13, 2024 at 05:15:50PM +0900, Joe Hattori wrote:
> > Current implementation of .probe() leaks a reference of i2c_adapter.
> > Implement an error path and call put_device() on the obtained
> > i2c_adapter in it to fix this refcount bug.
> >
> > This bug was found by an experimental static analysis tool that I am
> > developing.
> >
> > Fixes: 0c275c30176b ("drm/bridge: Add bridge driver for display connectors")
> > Signed-off-by: Joe Hattori <joe@xxxxxxxxxxxxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/bridge/display-connector.c | 25 ++++++++++++++++------
> > 1 file changed, 19 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/display-connector.c b/drivers/gpu/drm/bridge/display-connector.c
> > index 72bc508d4e6e..84f1c3798d32 100644
> > --- a/drivers/gpu/drm/bridge/display-connector.c
> > +++ b/drivers/gpu/drm/bridge/display-connector.c
> > @@ -332,8 +332,11 @@ static int display_connector_probe(struct platform_device *pdev)
> > int ret;
> >
> > ret = display_connector_get_supply(pdev, conn, "dp-pwr");
> > - if (ret < 0)
> > - return dev_err_probe(&pdev->dev, ret, "failed to get DP PWR regulator\n");
> > + if (ret < 0) {
> > + ret = dev_err_probe(&pdev->dev, ret,
> > + "failed to get DP PWR regulator\n");
> > + goto err_put;
> > + }
> > }
> >
> > /* enable DDC */
> > @@ -345,19 +348,24 @@ static int display_connector_probe(struct platform_device *pdev)
> >
> > if (IS_ERR(conn->ddc_en)) {
> > dev_err(&pdev->dev, "Couldn't get ddc-en gpio\n");
> > - return PTR_ERR(conn->ddc_en);
> > + ret = PTR_ERR(conn->ddc_en);
> > + goto err_put;
> > }
> >
> > ret = display_connector_get_supply(pdev, conn, "hdmi-pwr");
> > - if (ret < 0)
> > - return dev_err_probe(&pdev->dev, ret, "failed to get HDMI +5V Power regulator\n");
> > + if (ret < 0) {
> > + ret = dev_err_probe(
> > + &pdev->dev, ret,
> > + "failed to get HDMI +5V Power regulator\n");
>
> ret = dev_err_probe(&pdev->dev, ret,
> "failed to get HDMI +5V Power regulator\n");
>
> > + goto err_put;
> > + }
> > }
> >
> > if (conn->supply) {
> > ret = regulator_enable(conn->supply);
> > if (ret) {
> > dev_err(&pdev->dev, "failed to enable PWR regulator: %d\n", ret);
> > - return ret;
> > + goto err_put;
> > }
> > }
> >
> > @@ -383,6 +391,11 @@ static int display_connector_probe(struct platform_device *pdev)
> > drm_bridge_add(&conn->bridge);
> >
> > return 0;
> > +
> > +err_put:
> > + if (conn->bridge.ddc)
>
> i2c_put_adapter() already has a NULL check.
Yes, fixed in the v2 patch.
>
> > + i2c_put_adapter(conn->bridge.ddc);
> > + return ret;
> > }
> >
> > static void display_connector_remove(struct platform_device *pdev)
>
> --
> Regards,
>
> Laurent Pinchart
Best,
Joe
