Commit 9dcfbc18 authored Dec 22, 2017 by Archit Taneja Committed by Rob Clark Jan 03, 2018

drm/msm: Fix NULL deref in adreno_load_gpu



The msm/kms driver should work even if there is no GPU device specified
in DT. Currently, we get a NULL dereference crash in adreno_load_gpu
since the driver assumes that priv->gpu_pdev is non-NULL.

Perform an additional check on priv->gpu_pdev before trying to retrieve
the msm_gpu pointer from it.

v2: Incorporate Jordan's comments:
- Simplify the check to share the same error message.
- Use dev_err_once() to avoid an error message every time we open the
  drm device fd.

Fixes: eec874ce (drm/msm/adreno: load gpu at probe/bind time)

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Acked-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

parent 7ddae82e

drivers/gpu/drm/msm/adreno/adreno_device.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -130,11 +130,14 @@ struct msm_gpu adreno_load_gpu(struct drm_device dev)
		{
		struct msm_drm_private *priv = dev->dev_private;
		struct platform_device *pdev = priv->gpu_pdev;
		struct msm_gpu *gpu = platform_get_drvdata(priv->gpu_pdev);
		struct msm_gpu *gpu = NULL;
		int ret;

		if (pdev)
		gpu = platform_get_drvdata(pdev);

		if (!gpu) {
		dev_err(dev->dev, "no adreno device\n");
		dev_err_once(dev->dev, "no GPU device was found\n");
		return NULL;
		}