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 90FEFC0218A for ; Tue, 28 Jan 2025 08:58:41 +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=8lhcJcU9VifPT37uEkW5319Vlk1wbJ3luglscDxRzIY=; b=rqu82kW/UF6bE9AsjrkYS/iLa9 PFKKzUSZIiIzpQ53zqY0mCW7t00jyq9Af/FUID+B1wgbN8Ugsa2TXtU/vD8bEUT4Nh9AZ7P5ZIVRX BkKlHY2fMabCiqKSWfY8Iw0Z9acrp/i6hafAZ403jiOXrAaOsBI0uDm7jII8I9GgnIDTyvMH+wFJl dHIsduTB50XFYe/efL6gQhE+zga23EKc9wpRNpPfyzhihaBlElJ/r+xyQUsxP5c8r1Tv/gVqf2dQ+ qEIdaoj8i9KDkbjI5Kv81Fgz9y9NsaLXZ6AsrJ1P29erd82eS9VnbJs4jH7TMlXoimriW7yK01m4K Uq64hoYA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tchQd-00000004ROL-3BxK; Tue, 28 Jan 2025 08:58:39 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tchQc-00000004RNy-0RX1 for linux-nvme@lists.infradead.org; Tue, 28 Jan 2025 08:58:39 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 0872E68C4E; Tue, 28 Jan 2025 09:58:34 +0100 (CET) Date: Tue, 28 Jan 2025 09:58:33 +0100 From: Christoph Hellwig To: Hannes Reinecke Cc: Christoph Hellwig , Keith Busch , Sagi Grimberg , linux-nvme@lists.infradead.org Subject: Re: [PATCH 04/10] nvme: add nvme_auth_derive_tls_psk() Message-ID: <20250128085833.GC25760@lst.de> References: <20250122165829.11603-1-hare@kernel.org> <20250122165829.11603-5-hare@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250122165829.11603-5-hare@kernel.org> 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-20250128_005838_288723_8D9DC5B3 X-CRM114-Status: GOOD ( 12.88 ) 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 > + info_len = strlen(psk_digest) + strlen(psk_prefix) + 5; Where does the magic 5 come from? > > + info = kzalloc(info_len, GFP_KERNEL); > + if (!info) { > + ret = -ENOMEM; > + goto out_free_prk; > + } > + > + put_unaligned_be16(psk_len, info); > + memcpy(info + 2, psk_prefix, strlen(psk_prefix)); > + sprintf(info + 2 + strlen(psk_prefix), "%02d %s", hmac_id, psk_digest); And this feels like we'd want a basic struct for this, even if it just is the len field and a flexible array. Which will also help the compiler to to do bounds checking using __counted_by.