From 85e5bff2767df679d4bc21604a4e293115c2a087 Mon Sep 17 00:00:00 2001
From: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>
Date: Tue, 31 Aug 2021 11:17:20 +0800
Subject: [PATCH] exfatfs_seek: return current location plus offset bytes when
 whence is SEEK_CUR

VELAPLATFO-195 VELAPLATFO-194

Change-Id: Ic81d3169f948e70ed5f87fca1b78ce5905f59c98
Signed-off-by: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>
---
 fs/exfat/exfat_vfs.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/fs/exfat/exfat_vfs.c b/fs/exfat/exfat_vfs.c
index 93c3cbd9f13..f354a8c6d73 100644
--- a/fs/exfat/exfat_vfs.c
+++ b/fs/exfat/exfat_vfs.c
@@ -463,16 +463,23 @@ static off_t exfatfs_seek(FAR struct file *filep, off_t offset, int whence)
 
   switch (whence)
     {
-      case SEEK_SET:
-          filep->f_pos = offset;
-          break;
-
       case SEEK_CUR:
           offset += filep->f_pos;
+
+      case SEEK_SET:
+          if (offset >= 0)
+            {
+              filep->f_pos = offset;
+            }
+          else
+            {
+              ret = -EINVAL;
+            }
+
           break;
 
       case SEEK_END:
-          filep->f_pos = priv->node->size;
+          filep->f_pos = priv->node->size + offset;
           break;
 
       default: