[FFmpeg-devel] [PATCH 2/2] avutil/executor: Fix stack overflow due to recursive call

[Zhao Zhili]

From: Zhao Zhili <zhilizhao at tencent.com>

av_executor_execute run the task directly when thread is disabled.
The task can schedule a new task by call av_executor_execute. This
forms an implicit recursive call. This patch removed the recursive
call.
---
 libavutil/executor.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavutil/executor.c b/libavutil/executor.c
index 89058fab2f..c145c51be9 100644
--- a/libavutil/executor.c
+++ b/libavutil/executor.c
@@ -58,6 +58,7 @@ struct AVExecutor {
     int die;
 
     AVTask *tasks;
+    int stack_depth;
 };
 
 static AVTask* remove_task(AVTask **prev, AVTask *t)
@@ -207,8 +208,12 @@ void av_executor_execute(AVExecutor *e, AVTask *t)
     }
 
     if (!e->thread_count || !HAVE_THREADS) {
+        if (e->stack_depth > 0)
+            return;
+        e->stack_depth++;
         // We are running in a single-threaded environment, so we must handle all tasks ourselves
         while (run_one_task(e, e->local_contexts))
             /* nothing */;
+        e->stack_depth--;
     }
 }
-- 
2.42.0