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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 41E44C54FCB for ; Fri, 24 Apr 2020 12:29:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1582E20776 for ; Fri, 24 Apr 2020 12:29:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587731341; bh=IN3dBcosvKC2QUoeyRI6B2svCXNsLO997YBPPyyQJAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=C2pHFugbTYythOfq4ofX1OD4LaHVoVqHZXZmWg2cd6UABhYaE78I47IcsLpIihr2n L8qVTEMGesuof7MqLrdswXiLYLJBk7wKNSjCgtNwTVsakKoGhYMZaNTFA7JfCv9x8C x3c+XdsLQg5E64xEZfbbn8OBi7rg4MPA+iCd76lw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728806AbgDXM3A (ORCPT ); Fri, 24 Apr 2020 08:29:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:54502 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728286AbgDXMYK (ORCPT ); Fri, 24 Apr 2020 08:24:10 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 992F0218AC; Fri, 24 Apr 2020 12:24:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587731049; bh=IN3dBcosvKC2QUoeyRI6B2svCXNsLO997YBPPyyQJAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QcKJCAVJWk0V069e672XlB1HrHenrPmgC1TWWpl4v1F6a1LI+NcVyhenBsShQrSQk 5SjoFSyrhvjVzNKQ0DHVvt8Bk8tVQk9F2RKhY3Af9SGjUkwIZRHkQPN0HB2XIR8RHQ RQVEK3FPXmH6sy82LuHLSqf4wASPlsi/RKVal53w= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Juergen Gross , Wei Liu , Sasha Levin , xen-devel@lists.xenproject.org Subject: [PATCH AUTOSEL 4.19 11/18] xen/xenbus: ensure xenbus_map_ring_valloc() returns proper grant status Date: Fri, 24 Apr 2020 08:23:48 -0400 Message-Id: <20200424122355.10453-11-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200424122355.10453-1-sashal@kernel.org> References: <20200424122355.10453-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 a1c17000129ba..e94a61eaeceb0 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -450,7 +450,14 @@ 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