From patchwork Fri Feb 3 09:42:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Huth X-Patchwork-Id: 13127299 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8EDDDC636D6 for ; Fri, 3 Feb 2023 09:43:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231672AbjBCJnp (ORCPT ); Fri, 3 Feb 2023 04:43:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35054 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232869AbjBCJnl (ORCPT ); Fri, 3 Feb 2023 04:43:41 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 013A428235 for ; Fri, 3 Feb 2023 01:42:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1675417370; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DqDRH/0lCXChL6lF9FhJdEI9fG4ptLvUYJEw5ZtLX0Q=; b=eieaYC6CuZQYmtSR0OIyqGzJNmQjsWQpX1qdtK8jkouDcCZv1Ujg/CQnyBZWRzefl/6Mzj NuWqMBISA1V8dVdQuipX/a5X+OPCx3oeocLPnEz418pOFutQ/ld4lT7kMmqQTgFJHPt04U mdIgwEEkWBqYebV3kFB/7TqRQkE/WBA= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-286-55hyVc76NsCFjAV8PUgtUw-1; Fri, 03 Feb 2023 04:42:47 -0500 X-MC-Unique: 55hyVc76NsCFjAV8PUgtUw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7D6DB85CBED; Fri, 3 Feb 2023 09:42:46 +0000 (UTC) Received: from thuth.com (unknown [10.39.192.204]) by smtp.corp.redhat.com (Postfix) with ESMTP id B417340C1423; Fri, 3 Feb 2023 09:42:43 +0000 (UTC) From: Thomas Huth To: kvm@vger.kernel.org, Paolo Bonzini , Sean Christopherson Cc: kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, kvm-riscv@lists.infradead.org, Marc Zyngier , James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , David Hildenbrand , linuxppc-dev@lists.ozlabs.org Subject: [PATCH 2/7] KVM: x86: Improve return type handling in kvm_vm_ioctl_get_nr_mmu_pages() Date: Fri, 3 Feb 2023 10:42:25 +0100 Message-Id: <20230203094230.266952-3-thuth@redhat.com> In-Reply-To: <20230203094230.266952-1-thuth@redhat.com> References: <20230203094230.266952-1-thuth@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org kvm_vm_ioctl_get_nr_mmu_pages() tries to return a "unsigned long" value, but its caller only stores ther return value in an "int" - which is also what all the other kvm_vm_ioctl_*() functions are returning. So returning values that do not fit into a 32-bit integer anymore does not work here. It's better to adjust the return type, add a sanity check and return an error instead if the value is too big. Signed-off-by: Thomas Huth --- arch/x86/kvm/x86.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index da4bbd043a7b..caa2541833dd 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6007,8 +6007,11 @@ static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm, return 0; } -static unsigned long kvm_vm_ioctl_get_nr_mmu_pages(struct kvm *kvm) +static int kvm_vm_ioctl_get_nr_mmu_pages(struct kvm *kvm) { + if (kvm->arch.n_max_mmu_pages > INT_MAX) + return -EOVERFLOW; + return kvm->arch.n_max_mmu_pages; }