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Date:   Wed, 16 Nov 2022 14:43:13 -0800
From:   Kees Cook <keescook@chromium.org>
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     linux-kernel@vger.kernel.org, patches@lists.linux.dev,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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Subject: Re: [PATCH v2 3/3] treewide: use get_random_u32_between() when
 possible
Message-ID: <202211161436.A45AD719A@keescook>
References: <20221114164558.1180362-1-Jason@zx2c4.com>
 <20221114164558.1180362-4-Jason@zx2c4.com>
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On Mon, Nov 14, 2022 at 05:45:58PM +0100, Jason A. Donenfeld wrote:
> -				(get_random_u32_below(1024) + 1) * PAGE_SIZE;
> +				get_random_u32_between(1, 1024 + 1) * PAGE_SIZE;

I really don't like "between". Can't this be named "inclusive" (and
avoid adding 1 everywhere, which seems ugly), or at least named
something less ambiguous?

> -		n = get_random_u32_below(100) + 1;
> +		n = get_random_u32_between(1, 101);

Because I find this much less readable. "Below 100" is clear: 0-99
inclusive, plus 1, so 1-100 inclusive. "Between 1 and 101" is not obvious
to me to mean: 1-100 inclusive.

These seem so much nicer:
	get_random_u32_inclusive(1, 1024)
	get_random_u32_inclusive(1, 100)

-- 
Kees Cook