From mboxrd@z Thu Jan 1 00:00:00 1970 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 AF90DC432BE for ; Fri, 27 Aug 2021 16:27:15 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2F9E360EFF for ; Fri, 27 Aug 2021 16:27:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 2F9E360EFF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=BLLN4+38cxpOS+JeU9kllGGSrKhVLYNej1sM/MnqI2A=; b=P3/x1lyMYAilgx DeQFbrhC6h5xD7G1yZkWe/4xSa5qtf0bfA44HqMjjEQxkoMX/+XdxkvVU+/DcON1KMevhlacscN5u 14OMA88YN9AqyPLkZfBjx1rnhnTJOPyXS9Zbp3ArrWusOvN2EALmWKiYjokaYUQqSM2Cq/Si3PXVA voZKOA6sec4ME+FVjh97NrVizrwkQWKUWeszCcxDgfAYKKoMcjZ2/+39Oa8bPDlsr5RhjW8PPR+ws 15seAekf7WlmaLY7plKLX/AGSygtS2qgkkoa0UHvMqcVwJBUH0JjzcTE7DYGDq+rsE7I6S6Qf6cw0 jfeeYyqBkvCfi31O3lFg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mJegn-00CkHw-LD; Fri, 27 Aug 2021 16:26:45 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mJegk-00CkH6-2E for linux-nvme@lists.infradead.org; Fri, 27 Aug 2021 16:26:43 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 5216C67373; Fri, 27 Aug 2021 18:26:36 +0200 (CEST) Date: Fri, 27 Aug 2021 18:26:36 +0200 From: Christoph Hellwig To: Hannes Reinecke Cc: Christoph Hellwig , "Martin K. Petersen" , Sagi Grimberg , linux-nvme@lists.infradead.org Subject: Re: [PATCH] nvmet: fixup buffer overrun in nvmet_subsys_attr_serial() Message-ID: <20210827162636.GA24829@lst.de> References: <20210827092926.9525-1-hare@suse.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210827092926.9525-1-hare@suse.de> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210827_092642_298936_B7ECC769 X-CRM114-Status: GOOD ( 13.70 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Fri, Aug 27, 2021 at 11:29:26AM +0200, Hannes Reinecke wrote: > The serial number is copied into the buffer via memcpy_and_pad() > with the length NVMET_SN_MAX_SIZE. So when printing out we also > need to take just that length as anything beyond that will be > uninitialized. > > Signed-off-by: Hannes Reinecke The normal way to print a potentially unterminated fixed length string would be something like: diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c index f74485c705ff2..d784f3c200b4c 100644 --- a/drivers/nvme/target/configfs.c +++ b/drivers/nvme/target/configfs.c @@ -1067,7 +1067,8 @@ static ssize_t nvmet_subsys_attr_serial_show(struct config_item *item, { struct nvmet_subsys *subsys = to_subsys(item); - return snprintf(page, PAGE_SIZE, "%s\n", subsys->serial); + return snprintf(page, PAGE_SIZE, "%*s\n", + NVMET_SN_MAX_SIZE, subsys->serial); } static ssize_t _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme