[PATCH 5.10] gpu/i915: fix error return in mmap_offset_attach()

[Alexandr Sapozhnkiov <alsp705@gmail.com>]

From: Alexandr Sapozhnikov <alsp705@gmail.com>

In the drm_vma_node_allow function, kmalloc may 
return NULL, in which case the file element will not be 
added to the mmo->vma_node list. It would be good to 
not ignore this event, but at least log an error message.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Alexandr Sapozhnikov <alsp705@gmail.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_mman.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index a2195e28b625..adaef8f09d59 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -706,8 +706,11 @@ mmap_offset_attach(struct drm_i915_gem_object *obj,
 	mmo = insert_mmo(obj, mmo);
 	GEM_BUG_ON(lookup_mmo(obj, mmap_type) != mmo);
 out:
-	if (file)
-		drm_vma_node_allow_once(&mmo->vma_node, file);
+	if (file) {
+		err = drm_vma_node_allow_once(&mmo->vma_node, file);
+		if (err)
+			goto err;
+	}
 	return mmo;
 
 err:
-- 
2.43.0