ext4: propagate error if creation of directory entry fails

In case the dir entry creation failed, ext4fs_write would later overwrite
a random inode, as inodeno was never initialized.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
diff --git a/fs/ext4/ext4_write.c b/fs/ext4/ext4_write.c
index 9200c47..a52804e 100644
--- a/fs/ext4/ext4_write.c
+++ b/fs/ext4/ext4_write.c
@@ -907,7 +907,9 @@
 		goto fail;
 	}
 
-	ext4fs_update_parent_dentry(filename, &inodeno, FILETYPE_REG);
+	inodeno = ext4fs_update_parent_dentry(filename, FILETYPE_REG);
+	if (inodeno == -1)
+		goto fail;
 	/* prepare file inode */
 	inode_buffer = zalloc(fs->inodesz);
 	if (!inode_buffer)