From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38737C433E0 for ; Mon, 11 Jan 2021 12:58:36 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C4BCE20728 for ; Mon, 11 Jan 2021 12:58:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C4BCE20728 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:50600 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kywmI-0002C5-IE for qemu-devel@archiver.kernel.org; Mon, 11 Jan 2021 07:58:34 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:34752) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kywSW-0005SU-Hs for qemu-devel@nongnu.org; Mon, 11 Jan 2021 07:38:09 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:53004) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kywST-0007Vm-4v for qemu-devel@nongnu.org; Mon, 11 Jan 2021 07:38:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610368682; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NhrZQ8CeR701Xf2prTYoUkC4bvjutfohkq6TklGKGIc=; b=a3bx2Tk97OSc9pli8KQTQPCN/CXgF78ifq1Gwe9yYH6oUnaL+NRSJhtFOKsJKelLglc5FU bJf/67WEh6LZeOlXGgrLdn02cnlcZ7OVtunMNSkswzdsjhtSEj/92JWWPzWAzGVvJOm1Gm +ohvHV3dejd988+Ea2baG3VOCH5QBLM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-571-xD49ArU3MqSJVxliTKUvmg-1; Mon, 11 Jan 2021 07:38:00 -0500 X-MC-Unique: xD49ArU3MqSJVxliTKUvmg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 20FA8100C601 for ; Mon, 11 Jan 2021 12:37:59 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 190CD1349A for ; Mon, 11 Jan 2021 12:37:59 +0000 (UTC) Received: from zmail17.collab.prod.int.phx2.redhat.com (zmail17.collab.prod.int.phx2.redhat.com [10.5.83.19]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id E931318095C7; Mon, 11 Jan 2021 12:37:58 +0000 (UTC) Date: Mon, 11 Jan 2021 07:37:58 -0500 (EST) From: Miroslav Rezanina To: Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= Message-ID: <379455623.32388376.1610368678443.JavaMail.zimbra@redhat.com> In-Reply-To: <5acb5521-fdd2-e511-9cc3-176086183dd5@redhat.com> References: <5acb5521-fdd2-e511-9cc3-176086183dd5@redhat.com> Subject: Re: [RHEL7 qemu-kvm PATCH 2/3] s390x: Fix vm name copy length MIME-Version: 1.0 X-Originating-IP: [10.40.192.93, 10.4.195.25] Thread-Topic: s390x: Fix vm name copy length Thread-Index: ZN616bK1A8UxRKsrV7p3folxnetS5Q== X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mrezanin@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=216.205.24.124; envelope-from=mrezanin@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.251, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" ----- Original Message ----- > From: "Philippe Mathieu-Daud=C3=A9" > To: mrezanin@redhat.com, qemu-devel@nongnu.org > Sent: Monday, January 11, 2021 1:10:07 PM > Subject: Re: [RHEL7 qemu-kvm PATCH 2/3] s390x: Fix vm name copy length >=20 > Hi Miroslav, >=20 > On 1/11/21 12:30 PM, mrezanin@redhat.com wrote: > > From: Miroslav Rezanina > >=20 > > There are two cases when vm name is copied but closing \0 can be lost > > in case name is too long (>=3D256 characters). > >=20 > > Updating length to copy so there is space for closing \0. > >=20 > > Signed-off-by: Miroslav Rezanina > > --- > > target/s390x/kvm.c | 2 +- > > target/s390x/misc_helper.c | 4 +++- > > 2 files changed, 4 insertions(+), 2 deletions(-) > >=20 > > diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c > > index b8385e6b95..2313b5727e 100644 > > --- a/target/s390x/kvm.c > > +++ b/target/s390x/kvm.c > > @@ -1918,7 +1918,7 @@ static void insert_stsi_3_2_2(S390CPU *cpu, __u64 > > addr, uint8_t ar) > > */ > > if (qemu_name) { > > strncpy((char *)sysib.ext_names[0], qemu_name, > > - sizeof(sysib.ext_names[0])); > > + sizeof(sysib.ext_names[0]) - 1); > > } else { > > strcpy((char *)sysib.ext_names[0], "KVMguest"); > > } >=20 > What about using strpadcpy() instead? >=20 > strpadcpy((char *)sysib.sysib_322.ext_names[0], > sizeof(sysib.sysib_322.ext_names[0]), > qemu_name ?: "KVMguest", '\0'); Hi Philippe,=20 I went with -1 here because code use memset to 0 few lines above this code,= so we now there are only zeroes in the array and we do not have to write them = again. >=20 > > diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c > > index 58dbc023eb..7c478b9e58 100644 > > --- a/target/s390x/misc_helper.c > > +++ b/target/s390x/misc_helper.c > > @@ -369,8 +369,10 @@ uint32_t HELPER(stsi)(CPUS390XState *env, uint64_t= a0, > > uint64_t r0, uint64_t r1) > > ebcdic_put(sysib.sysib_322.vm[0].name, qemu_name, > > MIN(sizeof(sysib.sysib_322.vm[0].name), > > strlen(qemu_name))); > > +=09=09memset((char *)sysib.sysib_322.ext_names[0], 0, > > +=09=09 sizeof(sysib.sysib_322.ext_names[0])); > > strncpy((char *)sysib.sysib_322.ext_names[0], qemu_nam= e, > > - sizeof(sysib.sysib_322.ext_names[0])); > > + sizeof(sysib.sysib_322.ext_names[0]) - 1); >=20 > And here: >=20 > strpadcpy((char *)sysib.sysib_322.ext_names[0], > sizeof(sysib.sysib_322.ext_names[0]), > qemu_name, '\0'); However, here we are adding memset so using strpadcpy is better choice to ensure we have \0 after name string. Mirek >=20 > > } else { > > ebcdic_put(sysib.sysib_322.vm[0].name, "TCGguest", 8); > > strcpy((char *)sysib.sysib_322.ext_names[0], "TCGguest= "); > >=20 >=20 >=20 --=20 Miroslav Rezanina Software Engineer - Virtualization Team Maintainer