Re: [PATCH] color: protect against out-of-bounds array access/assignment

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 2, 2018, 17:36 UTC
Message-ID: <xmqqftzw3c21.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <nycvar.QRO.7.76.6.1808021438460.71@tvgsbejvaqbjf.bet>

Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

Show 14 quoted lines

> Hi Eric,
>
> On Thu, 2 Aug 2018, Eric Sunshine wrote:
>
>> want_color_fd() is designed to work only with standard input, output,
>> and error file descriptors, and stores information about each descriptor
>> in an array. However, it doesn't verify that the passed-in descriptor
>> lives within that set, which, with a buggy caller, could lead to
>> access/assignment outside the array bounds.
>
> ACK!
>
> Thanks,
> Dscho

Did you write a buggy caller that would have been caught or helped with this change? You did not write the callee that is made more defensive with this patch, so I am being curious as to where that Ack is coming from (I wouldn't have felt curious if this were a reviewed-by instead).

In any case, this looks like a good defensive measure.