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 D1CB6C38A2B for ; Thu, 10 Mar 2022 14:33:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244444AbiCJOd0 (ORCPT ); Thu, 10 Mar 2022 09:33:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244086AbiCJO22 (ORCPT ); Thu, 10 Mar 2022 09:28:28 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 95F79BD2F9; Thu, 10 Mar 2022 06:23:14 -0800 (PST) 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 C439BB82676; Thu, 10 Mar 2022 14:23:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 05D6EC340E8; Thu, 10 Mar 2022 14:23:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1646922185; bh=uwDr3cv7AGRRm8ArEDBYRUPoxrkysORCSNU0BMP31ug=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nJx9bp65aNKA3h45xi2OrH9yPwVP9YqdTzpe7fdpJJwSZdkaW9R8xzBknnmCuY70a AaMBVafDR8n5SHkLSMSFwF8hLqlnU3RXC2cU9wZk5O6vukW2JgQQioWCBbBp/DfqWR 4+yJvKG620vVeS8H0Z/d8MM08fob67//pFvjibp4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Simon Gaiser , Juergen Gross , Jan Beulich Subject: [PATCH 4.19 31/33] xen/pvcalls: use alloc/free_pages_exact() Date: Thu, 10 Mar 2022 15:18:58 +0100 Message-Id: <20220310140808.662126017@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220310140807.749164737@linuxfoundation.org> References: <20220310140807.749164737@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: Juergen Gross Commit b0576cc9c6b843d99c6982888d59a56209341888 upstream. Instead of __get_free_pages() and free_pages() use alloc_pages_exact() and free_pages_exact(). This is in preparation of a change of gnttab_end_foreign_access() which will prohibit use of high-order pages. This is part of CVE-2022-23041 / XSA-396. Reported-by: Simon Gaiser Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Signed-off-by: Greg Kroah-Hartman --- drivers/xen/pvcalls-front.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -346,8 +346,8 @@ static void free_active_ring(struct sock if (!map->active.ring) return; - free_pages((unsigned long)map->active.data.in, - map->active.ring->ring_order); + free_pages_exact(map->active.data.in, + PAGE_SIZE << map->active.ring->ring_order); free_page((unsigned long)map->active.ring); } @@ -361,8 +361,8 @@ static int alloc_active_ring(struct sock goto out; map->active.ring->ring_order = PVCALLS_RING_ORDER; - bytes = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, - PVCALLS_RING_ORDER); + bytes = alloc_pages_exact(PAGE_SIZE << PVCALLS_RING_ORDER, + GFP_KERNEL | __GFP_ZERO); if (!bytes) goto out;