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 Thu, 31 Oct 2019 01:08:21 +0300 (MSK)
References: <71d3e28eadd9ca54d5f564ed25d4276d472d5e6d.1572432961.git.imeevma@gmail.com>
From: Vladislav Shpilevoy <v.shpilevoy@tarantool.org>
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Date: Wed, 30 Oct 2019 23:13:54 +0100
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Subject: Re: [Tarantool-patches] [PATCH v1 1/1] netbox: fix memleak in
 lbox_tuple_format_new()
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To: imeevma@tarantool.org
Cc: tarantool-patches@freelists.org, tarantool-patches@dev.tarantool.org

Hi! Thanks for the patch!

On 30/10/2019 11:58, imeevma@tarantool.org wrote:
> Memleak appeared due to the fact that when creating a dictionary
> its reference count is 1 from the beginning. Later, when the
> dictionary is used to create tuple_format, its reference counter
> increased by 1 and it became equal to 2. After removing
> tuple_format, the reference counter for dict decreased by one, so
> it became equal to 1. Since ref counter is not equal to 0, dict
> not deleted, causing a memory leak.
> 
> Closes #4588
> ---
>  src/box/lua/misc.cc | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/src/box/lua/misc.cc b/src/box/lua/misc.cc
> index 7b8b9dc..102194e 100644
> --- a/src/box/lua/misc.cc
> +++ b/src/box/lua/misc.cc
> @@ -233,6 +233,7 @@ lbox_tuple_format_new(struct lua_State *L)
>  				 NULL, 0, 0, dict, false, false);
>  	if (format == NULL)
>  		return luaT_error(L);

The dict should be unreferenced regardless of tuple_format_new()
result. Now there is a leak, when format == NULL.

> +	tuple_dictionary_unref(dict);
>  	return lbox_push_tuple_format(L, format);
>  }
>