From e5f8acab97a4a9400a4f8d492d79c48bd1823245 Mon Sep 17 00:00:00 2001
From: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>
Date: Sun, 31 Oct 2021 12:29:59 +0800
Subject: [PATCH] ftruncate: sanity check for parameter:length

Signed-off-by: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>
---
 fs/vfs/fs_truncate.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/vfs/fs_truncate.c b/fs/vfs/fs_truncate.c
index 17b89edab65..4ecd06c13d4 100644
--- a/fs/vfs/fs_truncate.c
+++ b/fs/vfs/fs_truncate.c
@@ -155,7 +155,12 @@ int file_truncate(FAR struct file *filep, off_t length)
 int ftruncate(int fd, off_t length)
 {
   FAR struct file *filep;
-  int ret;
+  int ret = -EINVAL;
+
+  if (length < 0)
+    {
+      goto errout;
+    }
 
   /* Get the file structure corresponding to the file descriptor. */