From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753812AbdK1MWu (ORCPT ); Tue, 28 Nov 2017 07:22:50 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:58144 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752069AbdK1K3b (ORCPT ); Tue, 28 Nov 2017 05:29:31 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Juston Li , Dan Williams Subject: [PATCH 4.4 47/96] libnvdimm, namespace: fix label initialization to use valid seq numbers Date: Tue, 28 Nov 2017 11:22:56 +0100 Message-Id: <20171128100505.984501861@linuxfoundation.org> X-Mailer: git-send-email 2.15.0 In-Reply-To: <20171128100503.067621614@linuxfoundation.org> References: <20171128100503.067621614@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Williams commit b18d4b8a25af6fe83d7692191d6ff962ea611c4f upstream. The set of valid sequence numbers is {1,2,3}. The specification indicates that an implementation should consider 0 a sign of a critical error: UEFI 2.7: 13.19 NVDIMM Label Protocol Software never writes the sequence number 00, so a correctly check-summed Index Block with this sequence number probably indicates a critical error. When software discovers this case it treats it as an invalid Index Block indication. While the expectation is that the invalid block is just thrown away, the Robustness Principle says we should fix this to make both sequence numbers valid. Fixes: f524bf271a5c ("libnvdimm: write pmem label set") Reported-by: Juston Li Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- drivers/nvdimm/label.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/nvdimm/label.c +++ b/drivers/nvdimm/label.c @@ -823,7 +823,7 @@ static int init_labels(struct nd_mapping nsindex = to_namespace_index(ndd, 0); memset(nsindex, 0, ndd->nsarea.config_size); for (i = 0; i < 2; i++) { - int rc = nd_label_write_index(ndd, i, i*2, ND_NSINDEX_INIT); + int rc = nd_label_write_index(ndd, i, 3 - i, ND_NSINDEX_INIT); if (rc) return rc;