From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 7 Oct 2022 21:21:20 -0600 From: "Jason A. Donenfeld" Subject: Re: [PATCH v4 2/6] treewide: use prandom_u32_max() when possible Message-ID: References: <20221007180107.216067-1-Jason@zx2c4.com> <20221007180107.216067-3-Jason@zx2c4.com> <202210071241.445289C5@keescook> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <202210071241.445289C5@keescook> 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-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: Kees Cook Cc: linux-kernel@vger.kernel.org, patches@lists.linux.dev, Andreas Noever , Andrew Morton , Andy Shevchenko , Borislav Petkov , Catalin Marinas , Christoph =?utf-8?Q?B=C3=B6hmwalder?= , Christoph Hellwig , Christophe Leroy , Daniel Borkmann , Dave Airlie , Dave Hansen , "David S . Miller" , Eric Dumazet , Florian Westphal , Greg Kroah-Hartman , "H . Peter Anvin" , Heiko Carstens , Helge Deller , Herbert Xu , Huacai Chen , Hugh Dickins , Jakub Kicinski , "James E . J . Bottomley" , Jan Kara , Jason Gunthorpe , Jens Axboe , Johannes Berg , Jonathan Corbet , Jozsef Kadlecsik , KP Singh , Marco Elver , Mauro Carvalho Chehab , Michael Ellerman , Pablo Neira Ayuso , Paolo Abeni , Peter Zijlstra , Richard Weinberger , Russell King , Theodore Ts'o , Thomas Bogendoerfer , Thomas Gleixner , Thomas Graf , Ulf Hansson , Vignesh Raghavendra , WANG Xuerui , Will Deacon , Yury Norov , dri-devel@lists.freedesktop.org, kasan-dev@googlegroups.com, kernel-janitors@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-block@vger.kernel.org, linux-crypto@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-media@vger.kernel.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-mmc@vger.kernel.org, linux-mtd@lists.infradead.org, linux-nvme@lists.infradead.org, linux-parisc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-s390@vger.kernel.org, linux-um@lists.infradead.org, linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, netdev@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org, Jan Kara On Fri, Oct 07, 2022 at 03:47:44PM -0700, Kees Cook wrote: > > diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c > > index 4f2f2d1bac56..56ffaa8dd3f6 100644 > > --- a/lib/test_vmalloc.c > > +++ b/lib/test_vmalloc.c > > @@ -151,9 +151,7 @@ static int random_size_alloc_test(void) > > int i; > > > > for (i = 0; i < test_loop_count; i++) { > > - n = prandom_u32(); > > - n = (n % 100) + 1; > > - > > + n = prandom_u32_max(n % 100) + 1; > > p = vmalloc(n * PAGE_SIZE); > > > > if (!p) > > This looks wrong. Cocci says: > > - n = prandom_u32(); > - n = (n % 100) + 1; > + n = prandom_u32_max(100) + 1; I agree that's wrong, but what rule did you use to make Cocci generate that? Jason _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um