From patchwork Fri Sep 22 06:04:47 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hannes Reinecke X-Patchwork-Id: 9965199 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 49A176020C for ; Fri, 22 Sep 2017 06:05:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3C90F21E5A for ; Fri, 22 Sep 2017 06:05:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3164628935; Fri, 22 Sep 2017 06:05:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3190521E5A for ; Fri, 22 Sep 2017 06:05:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751838AbdIVGFB (ORCPT ); Fri, 22 Sep 2017 02:05:01 -0400 Received: from mx2.suse.de ([195.135.220.15]:42568 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751637AbdIVGFA (ORCPT ); Fri, 22 Sep 2017 02:05:00 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 70524AF50; Fri, 22 Sep 2017 06:04:59 +0000 (UTC) From: Hannes Reinecke To: "Martin K. Petersen" Cc: Christoph Hellwig , James Bottomley , Bart van Assche , linux-scsi@vger.kernel.org, Hannes Reinecke , Hannes Reinecke Subject: [PATCHv5 5/5] scsi_devinfo: fixup string compare Date: Fri, 22 Sep 2017 08:04:47 +0200 Message-Id: <1506060287-87031-6-git-send-email-hare@suse.de> X-Mailer: git-send-email 1.8.5.6 In-Reply-To: <1506060287-87031-1-git-send-email-hare@suse.de> References: <1506060287-87031-1-git-send-email-hare@suse.de> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When checking the model and vendor string we need to use the minimum value of either string, otherwise we'll miss out on wildcard matches. And we should take card when matching with zero size strings; results might be unpredictable. With this patch the rules for matching devinfo strings are as follows: - Vendor strings must match exactly - Empty Model strings will only match if the devinfo model is also empty - Model strings shorter than the devinfo model string will not match Fixes: 5e7ff2c ("SCSI: fix new bug in scsi_dev_info_list string matching") Signed-off-by: Hannes Reinecke Reviewed-by: Alan Stern Reviewed-by: Bart Van Assche --- drivers/scsi/scsi_devinfo.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/scsi/scsi_devinfo.c b/drivers/scsi/scsi_devinfo.c index 6858ad87dac1..d39b27cf8ed9 100644 --- a/drivers/scsi/scsi_devinfo.c +++ b/drivers/scsi/scsi_devinfo.c @@ -399,8 +399,8 @@ EXPORT_SYMBOL(scsi_dev_info_list_add_keyed); /** * scsi_dev_info_list_find - find a matching dev_info list entry. - * @vendor: vendor string - * @model: model (product) string + * @vendor: full vendor string + * @model: full model (product) string * @key: specify list to use * * Description: @@ -415,7 +415,7 @@ static struct scsi_dev_info_list *scsi_dev_info_list_find(const char *vendor, struct scsi_dev_info_list *devinfo; struct scsi_dev_info_list_table *devinfo_table = scsi_devinfo_lookup_by_key(key); - size_t vmax, mmax; + size_t vmax, mmax, mlen; const char *vskip, *mskip; if (IS_ERR(devinfo_table)) @@ -454,15 +454,18 @@ static struct scsi_dev_info_list *scsi_dev_info_list_find(const char *vendor, dev_info_list) { if (devinfo->compatible) { /* - * Behave like the older version of get_device_flags. + * vendor strings must be an exact match */ - if (memcmp(devinfo->vendor, vskip, vmax) || - (vmax < sizeof(devinfo->vendor) && - devinfo->vendor[vmax])) + if (vmax != strlen(devinfo->vendor) || + memcmp(devinfo->vendor, vskip, vmax)) continue; - if (memcmp(devinfo->model, mskip, mmax) || - (mmax < sizeof(devinfo->model) && - devinfo->model[mmax])) + + /* + * @model specifies the full string, and + * must be larger or equal to devinfo->model + */ + mlen = strlen(devinfo->model); + if (mmax < mlen || memcmp(devinfo->model, mskip, mlen)) continue; return devinfo; } else {