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=-8.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 1F6E8C433E0 for ; Fri, 12 Feb 2021 12:33:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DFE8664DEE for ; Fri, 12 Feb 2021 12:33:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231473AbhBLMdH (ORCPT ); Fri, 12 Feb 2021 07:33:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:53726 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231401AbhBLMcw (ORCPT ); Fri, 12 Feb 2021 07:32:52 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id C0CD964DEE; Fri, 12 Feb 2021 12:32:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1613133132; bh=SwpDPlc1sS/6olGE5QWH+xrx1QzaQAKD+39i9frVaUg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hgW4xVuRDSAqphHjttIz0VyMlYQpp71InUo/xIDF7XENwTJe5XVikOFafVd0tzsRG 3JdiZAAMi3MO/j3urLfnpz80QdJJGac9lpm0BwQ221ytGwfh55sgQbjwORXYOYdQEN mdC21wrxrIvYwpadfgPDrOgeHV8/q0WaHX1k5/HhqfGellC6gI37SNX2jAnz/4N6za L/blOOYExMdb1hSoN3vDJC0Q+bvzSOqUfRV3l9D1fDyL2mE/dYZt8nEp5xtvR1vk6/ TmPFiZB6bEqWCVh6E3zeWJXKCmmtq32HJQxmcBS6WLOTyxgciHFu/rMlI+m0OmYEib W8/QGXz+fafZg== Date: Fri, 12 Feb 2021 12:31:18 +0000 From: Mark Brown To: Nicolas Saenz Julienne Cc: Robin Murphy , Phil Elwell , linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] spi: Skip zero-length transfers in spi_transfer_one_message() Message-ID: <20210212123118.GB6057@sirena.org.uk> References: <20210211180820.25757-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="U+BazGySraz5kW0T" Content-Disposition: inline In-Reply-To: <20210211180820.25757-1-nsaenzjulienne@suse.de> X-Cookie: One size fits all. User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --U+BazGySraz5kW0T Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Feb 11, 2021 at 07:08:20PM +0100, Nicolas Saenz Julienne wrote: > - if (xfer->tx_buf || xfer->rx_buf) { > + if ((xfer->tx_buf || xfer->rx_buf) && xfer->len) { I think the issue here is more that some users were passing in buffers with zero length transfers, the above check was already intended to catch this case but was working on the assumption that if there was nothing to transfer then no buffer would be provided. --U+BazGySraz5kW0T Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmAmdRUACgkQJNaLcl1U h9ANBAf/ec1vXL9i3wJ+GOx2sxWeEvlBz0R3/jHeZSPQuSr92n0uuADcHjSOrB/E g+MIX5xTBstY0r4pHyMkeehUo5RcRDhojfKCe488GLJgWtRjhcCnKK9jC//AFCxR oOAdC5HhpK7z0nyXFEiaGqcXdGUQXzYELWLkwJ5XmV1axeWPLVYgILBSMZR8Lg7V rOZaw8TCyx2f79mRQpWOyc6xz8w+NaklJzO788oa2+HMK0oIlKAzr60IwStNllo6 fnt/bttxjAflij1m/jZNwRW2COWAwg1UcMU7nGW1onMBLH8Kix8isv8MqCEoB/5P CxOCgFp8K0cdX4nfmgpqhopJ1JUR4g== =wz+s -----END PGP SIGNATURE----- --U+BazGySraz5kW0T--