From patchwork Fri May 1 13:21:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 226478 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=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 238FEC4724C for ; Fri, 1 May 2020 14:00:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E70B2206D6 for ; Fri, 1 May 2020 14:00:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588341625; bh=GqiAjsB0umloZVqaiehWJl9SaeTz4QMV4YkOimw4U6U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=It9KnOgKIMiYZZJYH1K7jYn7nhpJQN/CKOlgMN9iRGpHzEagyo56/R5oGtYvNLU/u EKcIQswzmhL8b5UwSNYCmQIqUTY0tw2HKYYVHbFksFrBTLMzKm3HpJNkjUqAVgEclN CjW1+5qwreQp8U+F/Xiv0B7tB9KjMHyVzZeKt9cw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729462AbgEAN1c (ORCPT ); Fri, 1 May 2020 09:27:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:49864 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728947AbgEAN1a (ORCPT ); Fri, 1 May 2020 09:27:30 -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 9ED9424953; Fri, 1 May 2020 13:27:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588339650; bh=GqiAjsB0umloZVqaiehWJl9SaeTz4QMV4YkOimw4U6U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=f5agDgExmrnhM8rqsa2yW2N64bej4DJMXB5TQOu5/0wQMP8hLq3Ony39CGLXkfLJD zJQQE1r7/wrFHmej3hrAQbf1v4SC8ZcJLVison8BAm3artvws2zRzYZVkK1mxjkEWF tqxgIpK53aCgzNqWp+ds+D2cl0ATyxNNT3UDkg0g= 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 4.4 63/70] xen/xenbus: ensure xenbus_map_ring_valloc() returns proper grant status Date: Fri, 1 May 2020 15:21:51 +0200 Message-Id: <20200501131531.787932427@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200501131513.302599262@linuxfoundation.org> References: <20200501131513.302599262@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 056da6ee1a357..df27cefb2fa35 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -469,7 +469,14 @@ 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);