drm/msm: potential error pointer dereference in init()

[ Upstream commit b6816441a14bbe356ba8590de79cfea2de6a085c ]

The msm_iommu_new() returns error pointers on failure so check for that
to avoid an Oops.

Fixes: ccac7ce373c1 ("drm/msm: Refactor address space initialization")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20211004103806.GD25015@kili
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index c8217f4..b4a2e8e 100644 (file)
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -846,6 +846,10 @@ static int _dpu_kms_mmu_init(struct dpu_kms *dpu_kms)
                return 0;
 
        mmu = msm_iommu_new(dpu_kms->dev->dev, domain);
+       if (IS_ERR(mmu)) {
+               iommu_domain_free(domain);
+               return PTR_ERR(mmu);
+       }
        aspace = msm_gem_address_space_create(mmu, "dpu1",
                0x1000, 0x100000000 - 0x1000);