On Thu, 06 Apr 2017, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> While examining output from trial builds with -Wformat-security enabled,
> many strings were found that should be defined as "const", or as a char
> array instead of char pointer. This makes some static analysis easier,
> by producing fewer false positives.
>
> As these are all trivial changes, it seemed best to put them all in
> a single patch rather than chopping them up per maintainer.
> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> index f6d4d9700734..1ff9d5912b83 100644
> --- a/drivers/gpu/drm/drm_fb_helper.c
> +++ b/drivers/gpu/drm/drm_fb_helper.c
> @@ -2331,7 +2331,7 @@ EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
> int __init drm_fb_helper_modinit(void)
> {
> #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
> - const char *name = "fbcon";
> + const char name[] = "fbcon";
I'd always write the former out of habit. Why should I start using the
latter? What makes it better?
What keeps the kernel from accumulating tons more of the former?
Here's an interesting comparison of the generated code. I'm a bit
surprised by what gcc does, I would have expected no difference, like
clang. https://godbolt.org/g/OdqUvN
The other changes adding const in this patch are, of course, good.
BR,
Jani.
--
Jani Nikula, Intel Open Source Technology Center
