Re: [PATCH] rev-parse: Detect missing opt-spec

From: Eric Sunshine <sunshine@sunshineco.com>
Date: Sep 2, 2022, 05:46 UTC
Message-ID: <CAPig+cTAN1F1D=DxZF9jbUiTtc4UPnx0hZLLaVFKEecAa-gMsg@mail.gmail.com>
In-Reply-To: <20220902050621.94381-1-oystwa@gmail.com>

On Fri, Sep 2, 2022 at 1:10 AM Øystein Walle <oystwa@gmail.com> wrote:

Show 15 quoted lines

> If a line in parseopts's input starts with one of the flag characters it
> is erroneously parsed as a opt-spec where the short name of the option
> is the flag character itself and the long name is after the end of the
> string. This makes Git want to allocate SIZE_MAX bytes of memory at this
> line:
>
>     o->long_name = xmemdupz(sb.buf + 2, s - sb.buf - 2);
>
> Since s and sb.buf are equal the second argument is -2 (except unsigned)
> and xmemdupz allocates len + 1 bytes, ie. -1 meaning SIZE_MAX.
>
> Avoid this by checking whether a flag character was found in the zeroth
> position.
>
> Signed-off-by: Øystein Walle <oystwa@gmail.com>

Perhaps add a:

    Reported-by: Ingy dot Net <ingy@ingy.net>

trailer?

> diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
> @@ -479,6 +479,9 @@ static int cmd_parseopt(int argc, const char **argv, const char *prefix)
> +               if (s == sb.buf)
> +                       die(_("Missing opt-spec before option flags"));

There is a bit of a mix in this file already, but these days, we tend to start error messages with lowercase:

    die(_("missing opt-spec before option flags"));

Show 14 quoted lines

> diff --git a/t/t1502-rev-parse-parseopt.sh b/t/t1502-rev-parse-parseopt.sh
> @@ -306,6 +306,13 @@ test_expect_success 'test --parseopt help output: "wrapped" options normal "or:"
> +test_expect_success 'test --parseopt invalid opt-spec' '
> +       test_write_lines x -- "=, x" >spec &&
> +       echo "fatal: Missing opt-spec before option flags" >expect &&
> +       test_must_fail git rev-parse --parseopt -- >out <spec >actual 2>&1 &&
> +       test_cmp expect actual
> +'
> +
> @@ -337,3 +344,5 @@ test_expect_success 'test --parseopt help output: multi-line blurb after empty l
>
>  test_done
> +
> +test_done

Um? Debugging leftover?