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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E463C433F5 for ; Fri, 12 Nov 2021 09:57:56 +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 A02A860F4F for ; Fri, 12 Nov 2021 09:57:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org A02A860F4F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:57328 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mlTJi-0006aY-FX for qemu-devel@archiver.kernel.org; Fri, 12 Nov 2021 04:57:54 -0500 Received: from eggs.gnu.org ([209.51.188.92]:53370) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mlTIa-0005Vt-SY for qemu-devel@nongnu.org; Fri, 12 Nov 2021 04:56:44 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:58333) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mlTIY-0006Cu-JZ for qemu-devel@nongnu.org; Fri, 12 Nov 2021 04:56:43 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1636711001; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=L0E3VQ8yvvolO1cTFzzrDQHyUlah3aHUWglX08l+6m4=; b=SLMmbS9cUHHz0n0oDb0sLMQ9VfrbuDIo/AIno5KM8hvcy5QtLbkjUeCp+DdKU1Za5WbnFE hz1rWaQb6ew+mso2ddkT91q/JwlLwCqMvPTgvjriiT+4UZG9La4wbUq6+rxAdqi4gnf04K ByN6Y3Iw8DnYT8iBoKjqlICaaK9Re2s= 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-230-ynlK6N6bP6u1uL5in_4B1Q-1; Fri, 12 Nov 2021 04:56:38 -0500 X-MC-Unique: ynlK6N6bP6u1uL5in_4B1Q-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B418E19057A1; Fri, 12 Nov 2021 09:56:37 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.12]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 015D25DF21; Fri, 12 Nov 2021 09:56:19 +0000 (UTC) Date: Fri, 12 Nov 2021 09:56:17 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Roman Kagan , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , qemu-devel@nongnu.org, Kevin Wolf , qemu-block@nongnu.org, "Michael S. Tsirkin" , Raphael Norwitz , Hanna Reitz , yc-core@yandex-team.ru, =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Paolo Bonzini Subject: Re: [PATCH 05/10] vhost-backend: avoid overflow on memslots_limit Message-ID: References: <20211111153354.18807-1-rvkagan@yandex-team.ru> <20211111153354.18807-6-rvkagan@yandex-team.ru> <681e58cf-af57-3c5d-423d-49f32c86dfcf@redhat.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.0.7 (2021-05-04) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.699, 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_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Fri, Nov 12, 2021 at 10:46:46AM +0300, Roman Kagan wrote: > On Thu, Nov 11, 2021 at 06:59:43PM +0100, Philippe Mathieu-Daudé wrote: > > On 11/11/21 16:33, Roman Kagan wrote: > > > Fix the (hypothetical) potential problem when the value parsed out of > > > the vhost module parameter in sysfs overflows the return value from > > > vhost_kernel_memslots_limit. > > > > > > Signed-off-by: Roman Kagan > > > --- > > > hw/virtio/vhost-backend.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c > > > index b65f8f7e97..44f7dbb243 100644 > > > --- a/hw/virtio/vhost-backend.c > > > +++ b/hw/virtio/vhost-backend.c > > > @@ -58,7 +58,7 @@ static int vhost_kernel_memslots_limit(struct vhost_dev *dev) > > > if (g_file_get_contents("/sys/module/vhost/parameters/max_mem_regions", > > > &s, NULL, NULL)) { > > > uint64_t val = g_ascii_strtoull(s, NULL, 10); > > > > Would using qemu_strtou64() simplify this? > > I'm afraid not. None of the existing strtoXX converting functions has > the desired output range (0 < retval < INT_MAX), so the following > condition will remain necessary anyway; then it doesn't seem to matter > which particular parser is used to extract the value which is in the > range, so I left the one that was already there to reduce churn. If qemu_strtou64() can't handle all values in (0 < retval < INT_MAX) isn't that a bug in qemu_strtou64 ? Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|