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[198.0.35.241]) by smtp.gmail.com with ESMTPSA id a9-20020a170902710900b00183c6784704sm12680746pll.291.2022.11.16.14.43.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Nov 2022 14:43:14 -0800 (PST) Date: Wed, 16 Nov 2022 14:43:13 -0800 From: Kees Cook To: "Jason A. Donenfeld" Cc: linux-kernel@vger.kernel.org, patches@lists.linux.dev, Greg Kroah-Hartman , Jakub Kicinski , Russell King , Catalin Marinas , Thomas Bogendoerfer , Heiko Carstens , Herbert Xu , Christoph =?iso-8859-1?Q?B=F6hmwalder?= , Jani Nikula , Jason Gunthorpe , Sakari Ailus , "Martin K . Petersen" , Theodore Ts'o , Andreas Dilger , Jaegeuk Kim , Richard Weinberger , "Darrick J . Wong" , SeongJae Park , Thomas Gleixner , Andrew Morton , Michael Ellerman , Helge Deller , netdev@vger.kernel.org, linux-crypto@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-media@vger.kernel.org, linux-arm-kernel@lists.infradead.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-mmc@vger.kernel.org, linux-parisc@vger.kernel.org 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> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20221114164558.1180362-4-Jason@zx2c4.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221116_144317_582535_37FE63FD X-CRM114-Status: GOOD ( 11.53 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel