Re: [PATCH v2] reftable/writer: fix memory leak if write fails

> From: Lidong Yan <502024330056@smail.nju.edu.cn>
> 
> In reftable/writer.c:padded_write(), if w->writer failed, zeroed
> allocated in `reftable_calloc` will leak. w->writer could be
> `reftable_write_data` in reftable/stack.c, and could fail due to
> some write error. Simply add reftable_free(zeroed) will solve this
> problem.
> 
> In reftable/writer.c:writer_index_hash(), if `reftable_buf_add` failed,
> key allocated by `reftable_malloc` will not be insert into `obj_index_tree`
> thus leaks. Simple add reftable_free(key) will solve this problem.

> diff --git a/reftable/writer.c b/reftable/writer.c
> index cb16f71be49..3b4ebdd6dce 100644
> --- a/reftable/writer.c
> +++ b/reftable/writer.c
> @@ -57,8 +57,10 @@ static int padded_write(struct reftable_writer *w, uint8_t *data, size_t len,
>  			return -1;
>  
>  		n = w->write(w->write_arg, zeroed, w->pending_padding);
> -		if (n < 0)
> +		if (n < 0) {
> +			reftable_free(zeroed);
>  			return n;
> +		}
>  
>  		w->pending_padding = 0;
>  		reftable_free(zeroed);

> @@ -256,8 +258,10 @@ static int writer_index_hash(struct reftable_writer *w, struct reftable_buf *has
>  
>  		reftable_buf_reset(&key->hash);
>  		err = reftable_buf_add(&key->hash, hash->buf, hash->len);
> -		if (err < 0)
> +		if (err < 0) {
> +			reftable_free(key);
>  			return err;
> +		}
>  		tree_insert(&w->obj_index_tree, key,
>  			    &obj_index_tree_node_compare);
>  	} else {