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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 D6AA8C4724C for ; Fri, 1 May 2020 13:50:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A81BB2051A for ; Fri, 1 May 2020 13:50:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588341022; bh=IUCErDYU5+chUFB9+LblbUcLmt79a5CAIndVF79zzyc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QraPq5aDhwxkvEjd52oZmZ59ZsD5/LKcIcZU/WoCUMYsBWvaDeqqYTfcrBuKpo+aQ 2AtGZmUi7qRcKoxnJ4FZ7wrsfrqH+NYytHIlR0rKXMlTolPQb1mg7QS5RcfvVSGQbS uQdX8nDEZssGDxjJ0txhqv1ZEeAMIAs529ggBw0I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731391AbgEANuV (ORCPT ); Fri, 1 May 2020 09:50:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:40108 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731267AbgEANkI (ORCPT ); Fri, 1 May 2020 09:40:08 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B052B205C9; Fri, 1 May 2020 13:40:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588340408; bh=IUCErDYU5+chUFB9+LblbUcLmt79a5CAIndVF79zzyc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jSOZWJdjx1nmR1fwxkHfES4u6qnBHO96LuY3WAHUqi39XVlxWh6ifTba5YW4I/EnD 7QT4PkByCg04gk0wTaHE1ravVfxhFHRJJbDbLL1Zfs3REhidOwRDsVYqMnLU2v+ZjU BhvsOMlKdDYVZLZNll0GNGLYlxNzcbw3r0KhlNIM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Juergen Gross , Wei Liu , Sasha Levin Subject: [PATCH 5.4 66/83] xen/xenbus: ensure xenbus_map_ring_valloc() returns proper grant status Date: Fri, 1 May 2020 15:23:45 +0200 Message-Id: <20200501131540.943357495@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200501131524.004332640@linuxfoundation.org> References: <20200501131524.004332640@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Juergen Gross [ Upstream commit 6b51fd3f65a22e3d1471b18a1d56247e246edd46 ] xenbus_map_ring_valloc() maps a ring page and returns the status of the used grant (0 meaning success). There are Xen hypervisors which might return the value 1 for the status of a failed grant mapping due to a bug. Some callers of xenbus_map_ring_valloc() test for errors by testing the returned status to be less than zero, resulting in no error detected and crashing later due to a not available ring page. Set the return value of xenbus_map_ring_valloc() to GNTST_general_error in case the grant status reported by Xen is greater than zero. This is part of XSA-316. Signed-off-by: Juergen Gross Reviewed-by: Wei Liu Link: https://lore.kernel.org/r/20200326080358.1018-1-jgross@suse.com Signed-off-by: Juergen Gross Signed-off-by: Sasha Levin --- drivers/xen/xenbus/xenbus_client.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c index e17ca81561713..a38292ef79f6d 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -448,7 +448,14 @@ EXPORT_SYMBOL_GPL(xenbus_free_evtchn); int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs, unsigned int nr_grefs, void **vaddr) { - return ring_ops->map(dev, gnt_refs, nr_grefs, vaddr); + int err; + + err = ring_ops->map(dev, gnt_refs, nr_grefs, vaddr); + /* Some hypervisors are buggy and can return 1. */ + if (err > 0) + err = GNTST_general_error; + + return err; } EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc); -- 2.20.1