[PATCH] drm/i915/ttm: ensure we release the intel_memory_region

[Matthew Auld]

If the ttm_bo_init_reserved() call fails ensure we also release the
region, otherwise we leak the reference, or worse hit some uaf, when we
start using the objects.list. Also remove the make_unshrinkable call
here, which doesn't do anything.

Signed-off-by: Matthew Auld <matthew.a...@intel.com>
Cc: Thomas Hellström <thomas.hellst...@linux.intel.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c 
b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 771eb2963123..2e8cdcd5e4f7 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -909,7 +909,6 @@ int __i915_gem_ttm_object_init(struct intel_memory_region 
*mem,
        drm_gem_private_object_init(&i915->drm, &obj->base, size);
        i915_gem_object_init(obj, &i915_gem_ttm_obj_ops, &lock_class, flags);
        i915_gem_object_init_memory_region(obj, mem);
-       i915_gem_object_make_unshrinkable(obj);
        INIT_RADIX_TREE(&obj->ttm.get_io_page.radix, GFP_KERNEL | __GFP_NOWARN);
        mutex_init(&obj->ttm.get_io_page.lock);
        bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device :
@@ -932,7 +931,7 @@ int __i915_gem_ttm_object_init(struct intel_memory_region 
*mem,
                                   page_size >> PAGE_SHIFT,
                                   &ctx, NULL, NULL, i915_ttm_bo_destroy);
        if (ret)
-               return i915_ttm_err_to_gem(ret);
+               goto err_release_mr;
 
        obj->ttm.created = true;
        i915_ttm_adjust_domains_after_move(obj);
@@ -940,6 +939,10 @@ int __i915_gem_ttm_object_init(struct intel_memory_region 
*mem,
        i915_gem_object_unlock(obj);
 
        return 0;
+
+err_release_mr:
+       i915_gem_object_release_memory_region(obj);
+       return i915_ttm_err_to_gem(ret);
 }
 
 static const struct intel_memory_region_ops ttm_system_region_ops = {
-- 
2.26.3