From patchwork Sat Oct 14 21:03:51 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Disseldorp X-Patchwork-Id: 10006641 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 E09D360230 for ; Sat, 14 Oct 2017 21:04:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D32FA28FFE for ; Sat, 14 Oct 2017 21:04:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C7AC22903B; Sat, 14 Oct 2017 21:04:18 +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 3DD8028FFE for ; Sat, 14 Oct 2017 21:04:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751258AbdJNVER (ORCPT ); Sat, 14 Oct 2017 17:04:17 -0400 Received: from mx2.suse.de ([195.135.220.15]:60079 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751004AbdJNVER (ORCPT ); Sat, 14 Oct 2017 17:04:17 -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 mx2.suse.de (Postfix) with ESMTP id E9CCFADEC for ; Sat, 14 Oct 2017 21:04:15 +0000 (UTC) From: David Disseldorp To: target-devel@vger.kernel.org Cc: David Disseldorp Subject: [PATCH 1/2] target: fix PR state file path truncation detection Date: Sat, 14 Oct 2017 23:03:51 +0200 Message-Id: <20171014210352.8713-1-ddiss@suse.de> X-Mailer: git-send-email 2.13.6 Sender: target-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If an LIO backstore is configured with a sufficiently long Unit Serial string, alongside a similarly long dbroot path, then a truncated Persistent Reservation APTPL state file path will be used. This truncation can unintentionally lead to two LUs with differing serial numbers sharing PR state file. Fixes: fdddf932269a ("target: use new "dbroot" target attribute") Signed-off-by: David Disseldorp --- drivers/target/target_core_pr.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c index dd2cd8048582..61e6eed9cb86 100644 --- a/drivers/target/target_core_pr.c +++ b/drivers/target/target_core_pr.c @@ -1976,15 +1976,16 @@ static int __core_scsi3_write_aptpl_to_file( int ret; loff_t pos = 0; - memset(path, 0, 512); + memset(path, 0, sizeof(path)); - if (strlen(&wwn->unit_serial[0]) >= 512) { + ret = snprintf(path, sizeof(path), "%s/pr/aptpl_%s", + db_root, &wwn->unit_serial[0]); + if (ret >= sizeof(path)) { pr_err("WWN value for struct se_device does not fit" " into path buffer\n"); return -EMSGSIZE; } - snprintf(path, 512, "%s/pr/aptpl_%s", db_root, &wwn->unit_serial[0]); file = filp_open(path, flags, 0600); if (IS_ERR(file)) { pr_err("filp_open(%s) for APTPL metadata"