ext4: fix inode leak in ext4_xattr_inode_create() on an error path

commit e4db04f7d3dbbe16680e0ded27ea2a65b10f766a upstream.

There is issue as follows when do setxattr with inject fault:

[localhost]# fsck.ext4  -fn  /dev/sda
e2fsck 1.46.6-rc1 (12-Sep-2022)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Unattached zero-length inode 15.  Clear? no

Unattached inode 15
Connect to /lost+found? no

Pass 5: Checking group summary information

/dev/sda: ********** WARNING: Filesystem still has errors **********

/dev/sda: 15/655360 files (0.0% non-contiguous), 66755/2621440 blocks

This occurs in 'ext4_xattr_inode_create()'. If 'ext4_mark_inode_dirty()'
fails, dropping i_nlink of the inode is needed. Or will lead to inode leak.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221208023233.1231330-5-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 08043aa..2308ed0 100644 (file)
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -1441,6 +1441,9 @@ static struct inode *ext4_xattr_inode_create(handle_t *handle,
                if (!err)
                        err = ext4_inode_attach_jinode(ea_inode);
                if (err) {
+                       if (ext4_xattr_inode_dec_ref(handle, ea_inode))
+                               ext4_warning_inode(ea_inode,
+                                       "cleanup dec ref error %d", err);
                        iput(ea_inode);
                        return ERR_PTR(err);
                }