From owner-svn-src-all@freebsd.org Thu May 28 10:30:26 2020 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id AB09032D40B; Thu, 28 May 2020 10:30:26 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 49XkVT1r8fz4MXk; Thu, 28 May 2020 10:30:24 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kib@localhost [127.0.0.1]) by kib.kiev.ua (8.15.2/8.15.2) with ESMTPS id 04SAUGqK040874 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Thu, 28 May 2020 13:30:19 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua 04SAUGqK040874 Received: (from kostik@localhost) by tom.home (8.15.2/8.15.2/Submit) id 04SAUGLc040873; Thu, 28 May 2020 13:30:16 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Thu, 28 May 2020 13:30:16 +0300 From: Konstantin Belousov To: Justin Hibbits Cc: Brandon Bergren , src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r361568 - head/sys/powerpc/aim Message-ID: <20200528103016.GH48478@kib.kiev.ua> References: <202005280049.04S0n3jS096937@repo.freebsd.org> <20200527214101.59293529@titan.knownspace> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200527214101.59293529@titan.knownspace> X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FROM, NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on tom.home X-Rspamd-Queue-Id: 49XkVT1r8fz4MXk X-Spamd-Bar: + Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=gmail.com (policy=none); spf=softfail (mx1.freebsd.org: 2001:470:d5e7:1::1 is neither permitted nor denied by domain of kostikbel@gmail.com) smtp.mailfrom=kostikbel@gmail.com X-Spamd-Result: default: False [1.12 / 15.00]; ARC_NA(0.00)[]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_FROM(0.00)[gmail.com]; NEURAL_SPAM_SHORT(0.45)[0.446]; MIME_GOOD(-0.10)[text/plain]; HAS_XAW(0.00)[]; R_SPF_SOFTFAIL(0.00)[~all:c]; RCPT_COUNT_FIVE(0.00)[5]; NEURAL_SPAM_MEDIUM(0.30)[0.299]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_SPAM_LONG(0.37)[0.373]; FREEMAIL_TO(0.00)[gmail.com]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US]; RCVD_COUNT_TWO(0.00)[2]; FREEMAIL_ENVFROM(0.00)[gmail.com]; DMARC_POLICY_SOFTFAIL(0.10)[gmail.com : No valid SPF, No valid DKIM,none] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 May 2020 10:30:26 -0000 On Wed, May 27, 2020 at 09:41:01PM -0500, Justin Hibbits wrote: > On Thu, 28 May 2020 00:49:03 +0000 (UTC) > Brandon Bergren wrote: > > > Author: bdragon > > Date: Thu May 28 00:49:02 2020 > > New Revision: 361568 > > URL: https://svnweb.freebsd.org/changeset/base/361568 > > > > Log: > > [PowerPC] Fix radix crash when passing -1 from userspace > > > > Found by running libc tests with radix enabled. > > > > Detect unsigned integer wrapping with a postcondition. > > > > Note: Radix MMU is not enabled by default yet. > > > > Sponsored by: Tag1 Consulting, Inc. > > > > Modified: > > head/sys/powerpc/aim/mmu_radix.c > > > > Modified: head/sys/powerpc/aim/mmu_radix.c > > ============================================================================== > > --- head/sys/powerpc/aim/mmu_radix.c Wed May 27 23:20:35 > > 2020 (r361567) +++ head/sys/powerpc/aim/mmu_radix.c Thu > > May 28 00:49:02 2020 (r361568) @@ -6000,7 +6000,8 @@ > > mmu_radix_kremove(vm_offset_t va) int mmu_radix_map_user_ptr(pmap_t > > pm, volatile const void *uaddr, void **kaddr, size_t ulen, size_t > > *klen) { > > - if ((uintptr_t)uaddr + ulen >= VM_MAXUSER_ADDRESS) > > + if ((uintptr_t)uaddr + ulen >= VM_MAXUSER_ADDRESS || > > + (uintptr_t)uaddr + ulen < (uintptr_t)uaddr) > > return (EFAULT); > > > > *kaddr = (void *)(uintptr_t)uaddr; > > Wouldn't > > if ((uintptr_t)uaddr >= VM_MAXUSER_ADDRESS || > (uintptr_t)uaddr + ulen >= VM_MAXUSER_ADDRESS) > > be more appropriate? The committed change is the canonical way to detect unsigned overflow, so I think it is fine and does not depend on specific values of VM_MAXUSER_ADDRESS.