From 5e612aeb849b678b046e8249657f2fb70b055572 Mon Sep 17 00:00:00 2001
From: He Junyan <junyan.he@hotmail.com>
Date: Fri, 7 Feb 2020 23:56:13 +0800
Subject: [PATCH] libs: videopool: fix a condition race for pool allocate.

---
 gst-libs/gst/vaapi/gstvaapivideopool.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/gst-libs/gst/vaapi/gstvaapivideopool.c b/gst-libs/gst/vaapi/gstvaapivideopool.c
index faba367752..cb3ef3a6d4 100644
--- a/gst-libs/gst/vaapi/gstvaapivideopool.c
+++ b/gst-libs/gst/vaapi/gstvaapivideopool.c
@@ -179,6 +179,13 @@ gst_vaapi_video_pool_get_object_unlocked (GstVaapiVideoPool * pool)
     g_mutex_lock (&pool->mutex);
     if (!object)
       return NULL;
+
+    /* Others already allocated a new one before us during we
+       release the mutex */
+    if (pool->capacity && pool->used_count >= pool->capacity) {
+      gst_mini_object_unref (object);
+      return NULL;
+    }
   }
 
   ++pool->used_count;