From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933430AbeCNGQo (ORCPT ); Wed, 14 Mar 2018 02:16:44 -0400 Received: from mx-rz-2.rrze.uni-erlangen.de ([131.188.11.21]:41416 "EHLO mx-rz-2.rrze.uni-erlangen.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933184AbeCNGQm (ORCPT ); Wed, 14 Mar 2018 02:16:42 -0400 Authentication-Results: mx-rz-2.rrze.uni-erlangen.de; dkim=none reason="no signature"; dkim-adsp=none (unprotected policy); dkim-atps=neutral X-Quarantine-ID: X-Amavis-Alert: BAD HEADER SECTION, Header field occurs more than once: "References" occurs 3 times X-RRZE-Flag: Not-Spam X-RRZE-Submit-IP: 2003:d5:3e7:2500:bfbd:dba3:49d6:7204 From: Jonas Rabenstein To: Jonas Rabenstein , Scott Bauer , Jonathan Derrick , Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 8.4/8.4] block: sed-opal: check size of shadow mbr Date: Wed, 14 Mar 2018 07:15:45 +0100 Message-Id: <33f9dab3352e95588a7e4a4680beb068db285b7f.1521006596.git.jonas.rabenstein@studium.uni-erlangen.de> X-Mailer: git-send-email 2.16.1 In-Reply-To: References: In-Reply-To: References: <20180313154416.sgptuw7jcn7l76vn@sbauer-Z170X-UD5> References:

<20180313154416.sgptuw7jcn7l76vn@sbauer-Z170X-UD5> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Check whether the shadow mbr does fit in the provided space on the target. Also a proper firmware should handle this case and return an error we may prevent problem with crappy firmwares. Signed-off-by: Jonas Rabenstein --- block/sed-opal.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/block/sed-opal.c b/block/sed-opal.c index 4d93a6097ec0..8a08ae91bc25 100644 --- a/block/sed-opal.c +++ b/block/sed-opal.c @@ -1544,6 +1544,20 @@ static int write_shadow_mbr(struct opal_dev *dev, void *data) u64 len; int err = 0; + /* do we fit in the available shadow mbr space? */ + err = generic_get_table_info(dev, OPAL_MBR, OPAL_TABLE_ROWS); + if (err) { + pr_debug("MBR: could not get shadow size\n"); + return err; + } + + len = response_get_u64(&dev->parsed, 4); + if (shadow->offset + shadow->size > len) { + pr_debug("MBR: does not fit in shadow (%llu vs. %llu)\n", + shadow->offset + shadow->size, len); + return -ENOSPC; + } + /* FIXME: this is the maximum we can use for IO_BUFFER_LENGTH=2048. * Instead of having constant, it would be nice to compute the * actual value depending on IO_BUFFER_LENGTH -- 2.16.1