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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id D2046D111A8 for ; Mon, 1 Dec 2025 06:21:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/GP7XH0mMHlF93hqq8tafQl9hJEBAmK7d9HOHfbwCK4=; b=pASGVoltbEUMG6qxJ+momWbwRP 1tvA0XdZpJ+SxJhU3kPDBR1KgL07OacutTTkYNRnecOqLATIdyF12AK5RXJ5JGvo5DDxWSf+uBmkt hqLfh1cRMgtV8g1JsXjGBgH+zPWIQ0wrchoaA4Xh7DSBzj+lpggRZ5lxgDoNAYlDX3wW+TwGqwO0t HVz/ExRA7WJfvi8ZGeKhevMphohWFuyipYHStUamC9IiuzCyd3rJy/anRb3qKHHhtzWZzLtYg/YJ7 G0rmRXYdLoZJd1XEJ+JzTH1W7UntyhmLSywBuisFm3AbGKdIaFSW/iT22WdGU738C+TjFDoRv3e+z oUHqjGjQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vPxHr-00000002xsI-3uRq; Mon, 01 Dec 2025 06:21:27 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vPxHp-00000002xrW-2WsB for linux-nvme@lists.infradead.org; Mon, 01 Dec 2025 06:21:27 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id B43566732A; Mon, 1 Dec 2025 07:21:06 +0100 (CET) Date: Mon, 1 Dec 2025 07:21:06 +0100 From: Christoph Hellwig To: Eugene Korenevsky Cc: Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] nvme: nvme_identify_ns_descs: prevent oob Message-ID: <20251201062106.GA19164@lst.de> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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-20251130_222125_785353_F192EC56 X-CRM114-Status: GOOD ( 15.62 ) 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: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Sat, Nov 29, 2025 at 11:03:05PM +0300, Eugene Korenevsky wrote: > - int status, pos, len; > + int status, len, remain; Pre-existing issue, but all but len here should be unsigned. > + remain = NVME_IDENTIFY_DATA_SIZE; > + cur = data; > + while (remain >= sizeof(*cur)) { > if (cur->nidl == 0) > break; > + if (sizeof(*cur) + cur->nidl > remain) > + break; > > len = nvme_process_ns_desc(ctrl, &info->ids, cur, &csi_seen); > if (len < 0) > break; > > len += sizeof(*cur); > + remain -= len; > + cur += len; > } I don't think this works, cur is a nvme_ns_id_desc pointer, so it will be increased by len multiplied by the size of it. I think this would work muc heasier if you'd do away with remain, use and just use cur locally, and instead maintain an offet; Something like: offset = 0; do { cur = data + offset; ... offset += len; } while (offset < NVME_IDENTIFY_DATA_SIZE - sizeof(*cur));