Re: [PATCH] staging: bcm2835-camera: Initialise dev in v4l2_dev

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, Apr 14, 2025 at 06:41:47PM +0100, Dave Stevenson wrote:
> Commit 42a2f6664e18 ("staging: vc04_services: Move global g_state to
> vchiq_state") changed mmal_init to pass dev->v4l2_dev.dev to
> vchiq_mmal_init, however nothing iniitialised dev->v4l2_dev, so we got
> a NULL pointer dereference.
> 
> Set dev->v4l2_dev.dev during bcm2835_mmal_probe. The device pointer
> could be passed into v4l2_device_register to set it, however that also
> has other effects that would need additional changes.
> 
> Fixes: 42a2f6664e18 ("staging: vc04_services: Move global g_state to vchiq_state")
> Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> ---
> Noted as we switched to 6.12 that the driver would fail during probe
> with an invalid dereference if a camera module was actually configured
> for the legacy camera stack.
> https://github.com/raspberrypi/linux/issues/6753
> ---
>  drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> index b839b50ac26a..fa7ea4ca4c36 100644
> --- a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> +++ b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> @@ -1900,6 +1900,7 @@ static int bcm2835_mmal_probe(struct vchiq_device *device)
>  				__func__, ret);
>  			goto free_dev;
>  		}
> +		dev->v4l2_dev.dev = &device->dev;
>  
>  		/* setup v4l controls */
>  		ret = bcm2835_mmal_init_controls(dev, &dev->ctrl_handler);
> 
> ---
> base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8
> change-id: 20250410-staging-bcm2835-v4l2-fix-b8dbd933c23b
> 
> Best regards,
> -- 
> Dave Stevenson <dave.stevenson@raspberrypi.com>
> 
> 

Hi,

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