[PATCH next] drm/syncobj: Fix leak in drm_syncobj_import_sync_file_fence()

[Dan Carpenter <dan.carpenter@linaro.org>]

We need to cleanup if the chain = dma_fence_chain_alloc() allocation
fails.  Now that we have multiple error returns in this function, switch
to using an unwind ladder for cleanup.

Fixes: c2d3a7300695 ("drm/syncobj: Extend EXPORT_SYNC_FILE for timeline syncobjs")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 drivers/gpu/drm/drm_syncobj.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index 636cd83ca29e..c136d0c772dc 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -745,21 +745,24 @@ static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
 {
 	struct dma_fence *fence = sync_file_get_fence(fd);
 	struct drm_syncobj *syncobj;
+	int ret;
 
 	if (!fence)
 		return -EINVAL;
 
 	syncobj = drm_syncobj_find(file_private, handle);
 	if (!syncobj) {
-		dma_fence_put(fence);
-		return -ENOENT;
+		ret = -ENOENT;
+		goto err_put_fence;
 	}
 
 	if (point) {
 		struct dma_fence_chain *chain = dma_fence_chain_alloc();
 
-		if (!chain)
-			return -ENOMEM;
+		if (!chain) {
+			ret = -ENOMEM;
+			goto err_put_syncobj;
+		}
 
 		drm_syncobj_add_point(syncobj, chain, fence, point);
 	} else {
@@ -769,6 +772,13 @@ static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
 	dma_fence_put(fence);
 	drm_syncobj_put(syncobj);
 	return 0;
+
+err_put_syncobj:
+	drm_syncobj_put(syncobj);
+err_put_fence:
+	dma_fence_put(fence);
+
+	return ret;
 }
 
 static int drm_syncobj_export_sync_file(struct drm_file *file_private,
-- 
2.47.2