From patchwork Mon Feb 22 12:12:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 386232 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=-18.8 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, USER_AGENT_GIT 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 6E69CC433E9 for ; Mon, 22 Feb 2021 12:15:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 41D1764E77 for ; Mon, 22 Feb 2021 12:15:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230232AbhBVMOn (ORCPT ); Mon, 22 Feb 2021 07:14:43 -0500 Received: from mail.kernel.org ([198.145.29.99]:44826 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230135AbhBVMOe (ORCPT ); Mon, 22 Feb 2021 07:14:34 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id D155064E4B; Mon, 22 Feb 2021 12:13:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1613996007; bh=P8dOsg/8lT9BVQdxiQW7fh17THd0WtL4GaIUw8wy3m8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t7svRfeFF6hrTnwvvplgmrXplhnry8hZqlJYVgLx269AKBfK3vDptfN4+mofcUEu5 onAEkaYp8hPHpIFklbC3G5dtO0OqmM+fD/IO4a49aoKaqtx2A0kx6KZWiGLdV9TIMa 21vQrsjhNZzk6bb5Jkr6aAzaoyieKW2xuPygEwWc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jan Beulich , Juergen Gross Subject: [PATCH 5.11 04/12] Xen/gntdev: correct error checking in gntdev_map_grant_pages() Date: Mon, 22 Feb 2021 13:12:56 +0100 Message-Id: <20210222121017.861311432@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210222121013.586597942@linuxfoundation.org> References: <20210222121013.586597942@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jan Beulich commit ebee0eab08594b2bd5db716288a4f1ae5936e9bc upstream. Failure of the kernel part of the mapping operation should also be indicated as an error to the caller, or else it may assume the respective kernel VA is okay to access. Furthermore gnttab_map_refs() failing still requires recording successfully mapped handles, so they can be unmapped subsequently. This in turn requires there to be a way to tell full hypercall failure from partial success - preset map_op status fields such that they won't "happen" to look as if the operation succeeded. Also again use GNTST_okay instead of implying its value (zero). This is part of XSA-361. Signed-off-by: Jan Beulich Cc: stable@vger.kernel.org Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman --- drivers/xen/gntdev.c | 17 +++++++++-------- include/xen/grant_table.h | 1 + 2 files changed, 10 insertions(+), 8 deletions(-) --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -334,21 +334,22 @@ int gntdev_map_grant_pages(struct gntdev pr_debug("map %d+%d\n", map->index, map->count); err = gnttab_map_refs(map->map_ops, use_ptemod ? map->kmap_ops : NULL, map->pages, map->count); - if (err) - return err; for (i = 0; i < map->count; i++) { - if (map->map_ops[i].status) { + if (map->map_ops[i].status == GNTST_okay) + map->unmap_ops[i].handle = map->map_ops[i].handle; + else if (!err) err = -EINVAL; - continue; - } if (map->flags & GNTMAP_device_map) map->unmap_ops[i].dev_bus_addr = map->map_ops[i].dev_bus_addr; - map->unmap_ops[i].handle = map->map_ops[i].handle; - if (use_ptemod) - map->kunmap_ops[i].handle = map->kmap_ops[i].handle; + if (use_ptemod) { + if (map->kmap_ops[i].status == GNTST_okay) + map->kunmap_ops[i].handle = map->kmap_ops[i].handle; + else if (!err) + err = -EINVAL; + } } return err; } --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -157,6 +157,7 @@ gnttab_set_map_op(struct gnttab_map_gran map->flags = flags; map->ref = ref; map->dom = domid; + map->status = 1; /* arbitrary positive value */ } static inline void