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Date: Fri, 26 Jan 2024 14:57:30 -0800
From: Kees Cook <keescook@chromium.org>
To: Justin Stitt <justinstitt@google.com>
Cc: linux-hardening@vger.kernel.org,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Bill Wendling <morbo@google.com>, llvm@lists.linux.dev,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 01/82] overflow: Expand check_add_overflow() for pointer
 addition
Message-ID: <202401261456.3D126A50D7@keescook>
References: <20240122235208.work.748-kees@kernel.org>
 <20240123002814.1396804-1-keescook@chromium.org>
 <20240126225257.lfgeom4rhjzx2wrf@google.com>
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On Fri, Jan 26, 2024 at 10:52:57PM +0000, Justin Stitt wrote:
> [...]
> >  /**
> >   * check_sub_overflow() - Calculate subtraction with overflow checking
> 
> Does check_sub_overflow() deserve some more love in the future? I
> imagine "under"-flowing pointers is not at all common, though.

Yes, though I hadn't found any cases of it yet in the code, so I didn't
want to add a helper that would go unused. :)

> Nonetheless, this all looks good to me.
> 
> Reviewed-by: Justin Stitt <justinstitt@google.com>

Thanks!

-- 
Kees Cook