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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6D464C43219 for ; Mon, 24 Jan 2022 21:08:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1446521AbiAXVIj (ORCPT ); Mon, 24 Jan 2022 16:08:39 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:40348 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1389520AbiAXUlf (ORCPT ); Mon, 24 Jan 2022 15:41:35 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id C0643B810BD; Mon, 24 Jan 2022 20:41:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2AEC6C340E5; Mon, 24 Jan 2022 20:41:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643056892; bh=lllL1+YSQOwmnLAGhKuxtgJRcS5EeLGylTj5nvLlLTA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RyUC8CDcyCO7Q20D/Gkon9hOKwlvIFRhLuqxMsOQv9PNLBS5iPARoo33QUDqjxGsK E+UVfG1XLKgRAWvvikLQEzCNa1UrRgXWA7lK/Qwpdiu8N4JLJdapzLkeKlAfT7w/GZ vLuGDfvxJnQqi4hKoGrk/OuV3j01Un1n01YcxK3c= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexey Kardashevskiy , Michael Ellerman , Sasha Levin Subject: [PATCH 5.15 634/846] KVM: PPC: Book3S: Suppress warnings when allocating too big memory slots Date: Mon, 24 Jan 2022 19:42:31 +0100 Message-Id: <20220124184122.899954773@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184100.867127425@linuxfoundation.org> References: <20220124184100.867127425@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alexey Kardashevskiy [ Upstream commit 511d25d6b789fffcb20a3eb71899cf974a31bd9d ] The userspace can trigger "vmalloc size %lu allocation failure: exceeds total pages" via the KVM_SET_USER_MEMORY_REGION ioctl. This silences the warning by checking the limit before calling vzalloc() and returns ENOMEM if failed. This does not call underlying valloc helpers as __vmalloc_node() is only exported when CONFIG_TEST_VMALLOC_MODULE and __vmalloc_node_range() is not exported at all. Spotted by syzkaller. Signed-off-by: Alexey Kardashevskiy [mpe: Use 'size' for the variable rather than 'cb'] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210901084512.1658628-1-aik@ozlabs.ru Signed-off-by: Sasha Levin --- arch/powerpc/kvm/book3s_hv.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 7b74fc0a986b8..94da0d25eb125 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -4861,8 +4861,12 @@ static int kvmppc_core_prepare_memory_region_hv(struct kvm *kvm, unsigned long npages = mem->memory_size >> PAGE_SHIFT; if (change == KVM_MR_CREATE) { - slot->arch.rmap = vzalloc(array_size(npages, - sizeof(*slot->arch.rmap))); + unsigned long size = array_size(npages, sizeof(*slot->arch.rmap)); + + if ((size >> PAGE_SHIFT) > totalram_pages()) + return -ENOMEM; + + slot->arch.rmap = vzalloc(size); if (!slot->arch.rmap) return -ENOMEM; } -- 2.34.1