From: Chengguang Xu <cgxu519@gmx.com>
Date: Wed, 23 Jan 2019 06:12:25 +0000 (+0800)
Subject: staging: erofs: fix potential double iput in erofs_read_super()
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=94832d93992176b7c37672e1fc7b7acc16e70286;p=openwrt%2Fstaging%2Fblogic.git

staging: erofs: fix potential double iput in erofs_read_super()

Some error cases like failing from d_make_root() will
cause double iput because d_make_root() also does iput
in its error path.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Gao Xiang <gaoxiang25@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/staging/erofs/super.c b/drivers/staging/erofs/super.c
index af5140eede18..176fca2af379 100644
--- a/drivers/staging/erofs/super.c
+++ b/drivers/staging/erofs/super.c
@@ -421,13 +421,14 @@ static int erofs_read_super(struct super_block *sb,
 		errln("rootino(nid %llu) is not a directory(i_mode %o)",
 			ROOT_NID(sbi), inode->i_mode);
 		err = -EINVAL;
-		goto err_isdir;
+		iput(inode);
+		goto err_iget;
 	}
 
 	sb->s_root = d_make_root(inode);
 	if (sb->s_root == NULL) {
 		err = -ENOMEM;
-		goto err_makeroot;
+		goto err_iget;
 	}
 
 	/* save the device name to sbi */
@@ -453,10 +454,6 @@ static int erofs_read_super(struct super_block *sb,
 	 */
 err_devname:
 	dput(sb->s_root);
-err_makeroot:
-err_isdir:
-	if (sb->s_root == NULL)
-		iput(inode);
 err_iget:
 #ifdef EROFS_FS_HAS_MANAGED_CACHE
 	iput(sbi->managed_cache);