From: Junio C Hamano <gitster@pobox.com>
Date: Thu, 07 Feb 2019 02:47:55 GMT
Subject: Re: [PATCH v2] fetch-pack: clear alternate shallow when complete
Message-ID: <xmqq4l9gs49w.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <CACsJy8Ae0ZZjh8+f+TwbfJ-V9SzrHpDFyfjwScwKJj+kc7FDTQ@mail.gmail.com>

Duy Nguyen <pclouds@gmail.com> writes:

> On Thu, Feb 7, 2019 at 7:00 AM brian m. carlson
> <sandals@crustytoothpaste.net> 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.