Re: [PATCH] drm/client: Do not destroy NULL modes

[Ville Syrjälä <ville.syrjala@linux.intel.com>]

On Tue, Feb 24, 2026 at 10:12:28PM +0000, Jonathan Cavitt wrote:
> 'modes' in drm_client_modeset_probe may fail to kcalloc.  If this
> occurs, we jump to 'out', calling modes_destroy on it, which
> dereferences it.  This may result in a NULL pointer dereference in the
> error case.  Prevent that.
> 
> Fixes: 3039cc0c0653 ("drm/client: Make copies of modes")
> Signed-off-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>

Thanks. Pushed to drm-misc-fixes.

> ---
>  drivers/gpu/drm/drm_client_modeset.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_client_modeset.c b/drivers/gpu/drm/drm_client_modeset.c
> index 262b1b8773c5..bb49b8361271 100644
> --- a/drivers/gpu/drm/drm_client_modeset.c
> +++ b/drivers/gpu/drm/drm_client_modeset.c
> @@ -930,7 +930,8 @@ int drm_client_modeset_probe(struct drm_client_dev *client, unsigned int width,
>  	mutex_unlock(&client->modeset_mutex);
>  out:
>  	kfree(crtcs);
> -	modes_destroy(dev, modes, connector_count);
> +	if (modes)
> +		modes_destroy(dev, modes, connector_count);
>  	kfree(modes);
>  	kfree(offsets);
>  	kfree(enabled);
> -- 
> 2.43.0

-- 
Ville Syrjälä
Intel