drm/msm/dsi: fix memory corruption with too many bridges

commit 2e786eb2f9cebb07e317226b60054df510b60c65 upstream.

Add the missing sanity check on the bridge counter to avoid corrupting
data beyond the fixed-sized bridge array in case there are ever more
than eight bridges.

Fixes: a689554ba6 ("drm/msm: Initial add DSI connector support")
Cc: stable@vger.kernel.org	# 4.1
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/502668/
Link: https://lore.kernel.org/r/20220913085320.8577-4-johan+linaro@kernel.org
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2022-09-13 10:53:13 +02:00 committed by Greg Kroah-Hartman
parent 44a86d96fa
commit 21c4679af0

View File

@ -205,6 +205,12 @@ int msm_dsi_modeset_init(struct msm_dsi *msm_dsi, struct drm_device *dev,
return -EINVAL;
priv = dev->dev_private;
if (priv->num_bridges == ARRAY_SIZE(priv->bridges)) {
DRM_DEV_ERROR(dev->dev, "too many bridges\n");
return -ENOSPC;
}
msm_dsi->dev = dev;
ret = msm_dsi_host_modeset_init(msm_dsi->host, dev);