[PATCH] mtd: unlock on error in ioctl

[Dan Carpenter]

We need to unlock before returning on this error path.

Fixes: 210bec567936 ("mtd: properly check all write ioctls for permissions")
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
---
 drivers/mtd/mtdchar.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 52c120f9fb0d..05f9218592df 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -1064,8 +1064,10 @@ static long mtdchar_compat_ioctl(struct file *file, 
unsigned int cmd,
                struct mtd_oob_buf32 buf;
                struct mtd_oob_buf32 __user *buf_user = argp;
 
-               if (!(file->f_mode & FMODE_WRITE))
-                       return -EPERM;
+               if (!(file->f_mode & FMODE_WRITE)) {
+                       ret = -EPERM;
+                       goto unlock;
+               }
 
                if (copy_from_user(&buf, argp, sizeof(buf)))
                        ret = -EFAULT;
@@ -1117,6 +1119,7 @@ static long mtdchar_compat_ioctl(struct file *file, 
unsigned int cmd,
                ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
        }
 
+unlock:
        mutex_unlock(&mtd_mutex);
 
        return ret;
-- 
2.27.0