From: Tay Ray Chuan <rctay89@gmail.com>
Date: Thu, 11 Apr 2013 15:19:32 GMT
Subject: Re: git log -p unexpected behaviour - security risk?
Message-ID: <CALUzUxrp4+S-Nm-Scb9sT9sBw1mLEb3-CBc_P0KqL20qNmFO3w@mail.gmail.com>
In-Reply-To: <CAHQ6N+qdA5Lck1_ByOYPOG4ngsztz3HQSw8c_U_K8OnDapj4bQ@mail.gmail.com>

On Thu, Apr 11, 2013 at 6:36 PM, John Tapsell <johnflux@gmail.com> wrote:
>   I noticed that code that you put in merge will not be visible by
> default.  This seems like a pretty horrible security problem, no?
>
> I made the following test tree, with just 3 commits:
>
> https://github.com/johnflux/ExampleEvilness.git
>
> Doing "git log -p"  shows all very innocent commits.  Completely
> hidden is the change to add "EVIL CODE MUWHAHAHA".
>
> This seems really dangerous!
>
> The evil code only shows up with the non-default  --cc or -m  option.

For email-based patch workflows (eg. git, linux kernel), then this is
not a problem - the diff doesn't even show up, so nothing is applied
when git-am is run.

For github with pull-requests, a diff is shown between trees, so this
will show up.

--
Cheers,
Ray Chuan