drm/amdgpu: Fix possible null pointer dereference

fxkamd · alexdeucher · commit 51b79f338175 · 2023-10-19T18:56:50.000-04:00
abo->tbo.resource may be NULL in amdgpu_vm_bo_update. Fixes: 1802537 ("drm/ttm: stop allocating dummy resources during BO creation") Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1090,7 +1090,8 @@ int amdgpu_vm_bo_update(struct amdgpu_device *adev, struct amdgpu_bo_va *bo_va,
 			struct drm_gem_object *gobj = dma_buf->priv;
 			struct amdgpu_bo *abo = gem_to_amdgpu_bo(gobj);
 
-			if (abo->tbo.resource->mem_type == TTM_PL_VRAM)
+			if (abo->tbo.resource &&
+			    abo->tbo.resource->mem_type == TTM_PL_VRAM)
 				bo = gem_to_amdgpu_bo(gobj);
 		}
 		mem = bo->tbo.resource;

Original file line number	Diff line number	Diff line change
`@@ -1090,7 +1090,8 @@ int amdgpu_vm_bo_update(struct amdgpu_device adev, struct amdgpu_bo_va bo_va,`
`1090`	`1090`	`struct drm_gem_object *gobj = dma_buf->priv;`
`1091`	`1091`	`struct amdgpu_bo *abo = gem_to_amdgpu_bo(gobj);`
`1092`	`1092`
`1093`		`- if (abo->tbo.resource->mem_type == TTM_PL_VRAM)`
	`1093`	`+ if (abo->tbo.resource &&`
	`1094`	`+ abo->tbo.resource->mem_type == TTM_PL_VRAM)`
`1094`	`1095`	`bo = gem_to_amdgpu_bo(gobj);`
`1095`	`1096`	`}`
`1096`	`1097`	`mem = bo->tbo.resource;`