[FFmpeg-devel] [PATCH 2/3] avcodec/utils: Fix several integer overflows.

[Ronald S. Bultje]

Hi,

On Sun, Jun 4, 2017 at 6:32 AM, Nicolas George <george at nsup.org> wrote:

> Le quintidi 15 prairial, an CCXXV, James Almer a écrit :
> > On 6/3/2017 9:25 PM, Michael Niedermayer wrote:
> > I see EINVAL more fit as an error for example if src or dst are NULL,
> > something that would actually be an invalid argument.
> > We don't currently check that, for that matter. Maybe we should...
>
> This kind of case, I call "obviously invalid use of the API", and I
> think in these cases, an immediate crash is way better than an error
> code. The crash is already what happens here, since par and codec are
> immediately dereferenced. An av_assert0() would make it clearer.
>
> The same goes for every cases where passing NULL makes no sense, passing
> an invalid value where a small set of enumerated values / flags is
> expected (42 instead of SEEK_SET is an obvious example), or calling a
> amath function outside a simple interval.
>
> We may want to introduce something like av_assert_api() to have the
> failure message tell explicitly that the crash is caused by a bug in the
> application rather than the library.


This reminds me of g_return_val_if_fail in glib, and in some situations
it's quite sensible and helpful.

Ronald