ext4: fix uninitialized variable in ext4_inlinedir_to_tree

Syzbot has found an uninit-value bug in ext4_inlinedir_to_tree

This error happens because ext4_inlinedir_to_tree does not
handle the case when ext4fs_dirhash returns an error

This can be avoided by checking the return value of ext4fs_dirhash
and propagating the error,
similar to how it's done with ext4_htree_store_dirent

Signed-off-by: Xiaxi Shen <[email protected]>
Reported-and-tested-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=eaba5abe296837a640c0
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>

Author: xshen053

fs/ext4/inline.c

@@ -1410,7 +1410,11 @@ int ext4_inlinedir_to_tree(struct file *dir_file,
 			hinfo->hash = EXT4_DIRENT_HASH(de);
 			hinfo->minor_hash = EXT4_DIRENT_MINOR_HASH(de);
 		} else {
-			ext4fs_dirhash(dir, de->name, de->name_len, hinfo);
+			err = ext4fs_dirhash(dir, de->name, de->name_len, hinfo);
+			if (err) {
+				ret = err;
+				goto out;
+			}
 		}
 		if ((hinfo->hash < start_hash) ||
 		    ((hinfo->hash == start_hash) &&