# Re: \[PATCH v2\] fetch-pack: clear alternate shallow when complete

- From: Junio C Hamano \<hidden\>
- Date: 2019-02-07 02:48:01 
- List: git
- Page: https://ratatoskr.run/git/2019/02/7801002

```text
Duy Nguyen [ref] writes:

> On Thu, Feb 7, 2019 at 7:00 AM brian m. carlson
> [ref] wrote:
>>
>> When we write an alternate shallow file in update_shallow, we write it
>> into the lock file. The string stored in alternate_shallow_file is
>> copied from the lock file path, but it is freed the moment that the lock
>> file is closed, since we call strbuf_release to free that path.
>>
>> This used to work, since we did not invoke git index-pack more than
>> once. However, we now do, and starting with bd0b42aed3 (fetch-pack: do
>> not take shallow lock unnecessarily - 2019-01-10), we no longer reset
>> this value unconditionally; consequently, we reuse the freed memory.
>> Ensure we reset the value to NULL to avoid using freed memory. git
>> index-pack will read the repository's shallow file, which will have been
>> updated with the correct information.
>
> The patch looks good to me.

Thanks, all.
```