[PATCH 5.10 325/575] drm/msm: potential error pointer dereference in init()

[Greg Kroah-Hartman]

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ 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@xxxxxxxxxx>
Reviewed-by: Abhinav Kumar <abhinavk@xxxxxxxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20211004103806.GD25015@kili
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index c8217f4858a15..b4a2e8eb35dd2 100644
--- 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);
 
-- 
2.33.0