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: 8a3b4c17f863 ("drm/msm/dp: employ bridge mechanism for display enable 
and disable")
Cc: sta...@vger.kernel.org      # 5.17
Signed-off-by: Johan Hovold <johan+lin...@kernel.org>
---
 drivers/gpu/drm/msm/dp/dp_display.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c 
b/drivers/gpu/drm/msm/dp/dp_display.c
index 3e284fed8d30..fbe950edaefe 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -1604,6 +1604,12 @@ int msm_dp_modeset_init(struct msm_dp *dp_display, 
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;
+       }
+
        dp_display->drm_dev = dev;
 
        dp_priv = container_of(dp_display, struct dp_display_private, 
dp_display);
-- 
2.35.1

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