Subject: Re: What's cooking in git.git (Apr 2014, #08; Fri, 25)

From: Junio C Hamano <[email-masked]>
Date: Mon, 28 Apr 2014 10:48:21 -0700

Jeff King <[email-masked]> writes:

> On Fri, Apr 25, 2014 at 03:50:26PM -0700, Junio C Hamano wrote:
>
>> * jk/external-diff-use-argv-array (2014-04-21) 6 commits
>>   (merged to 'next' on 2014-04-22 at e6d92d7)
>>  + run_external_diff: refactor cmdline setup logic
>>  + run_external_diff: hoist common bits out of conditional
>>  + run_external_diff: drop fflush(NULL)
>>  + run_external_diff: clean up error handling
>>  + run_external_diff: use an argv_array for the environment
>>  + run_external_diff: use an argv_array for the command line
>> 
>>  Code clean-up.
>> 
>>  Will keep in 'next' for the remainder of the cycle.
>
> The first one does fix a possible stack overflow (albeit of one NULL,
> not arbitrary content, so I don't think it's exploitable). We may want
> to do:
>
> diff --git a/diff.c b/diff.c
> index 54d5308..a03744b 100644
> --- a/diff.c
> +++ b/diff.c
> @@ -2894,7 +2894,7 @@ static void run_external_diff(const char *pgm,
>  			      int complete_rewrite,
>  			      struct diff_options *o)
>  {
> -	const char *spawn_arg[10];
> +	const char *spawn_arg[11];
>  	int retval;
>  	const char **arg = &spawn_arg[0];
>  	struct diff_queue_struct *q = &diff_queued_diff;
>
> as a fix for maint/2.0.0 in the interim. I can write a commit message
> for that if you're interested.

I think we should merge the first one (and possibly the second one,
too) as-is for 2.0 instead.  No change can possibly be more
trivially correct than these two ;-)