Re: [PATCH] color: protect against out-of-bounds array access/assignment
- From
Eric Sunshine <sunshine@sunshineco.com>
- Date
- Aug 3, 2018, 06:43 UTC
- Message-ID
- <CAPig+cTbXt30ic+6T32zRRfBRAZo6LtgS+XGQ_Tw7UtFkbHYew@mail.gmail.com>
- In-Reply-To
- <20180803060749.GA237521@aiede.svl.corp.google.com>
On Fri, Aug 3, 2018 at 2:26 AM Jonathan Nieder <jrnieder@gmail.com> wrote:
Show 5 quoted lines
> Eric Sunshine wrote:
> > + if (fd < 0 || fd >= ARRAY_SIZE(want_auto))
> > + BUG("file descriptor out of range: %d", fd);
>
> The indentation looks wrong here.Yep, that's weird. I can't figure out how that got indented with four spaces rather than a TAB. I just re-typed the entire change in my editor as I believe I typed it earlier, and the editor correctly auto-indented it with a TAB. Odd. Thanks for catching it.
> Combining that with the other suggestions from this thread, I end up > with this v2:
This looks good to me. Thanks. And, if needed:
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
(patch left unsnipped)
Show 33 quoted lines
> -- >8 --
> From: Eric Sunshine <sunshine@sunshineco.com>
> Subject: color: protect against out-of-bounds reads and writes
>
> want_color_fd() is designed to work only with standard 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 or assignment outside the array bounds.
>
> Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
> Acked-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
> ---
> color.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/color.c b/color.c
> index b1c24c69de..ebb222ec33 100644
> --- a/color.c
> +++ b/color.c
> @@ -343,6 +343,9 @@ int want_color_fd(int fd, int var)
>
> static int want_auto[3] = { -1, -1, -1 };
>
> + if (fd < 1 || fd >= ARRAY_SIZE(want_auto))
> + BUG("file descriptor out of range: %d", fd);
> +
> if (var < 0)
> var = git_use_color_default;
>
> --
> 2.18.0.597.ga71716f1ad