From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:43668 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751741AbdLDN7g (ORCPT ); Mon, 4 Dec 2017 08:59:36 -0500 Subject: Patch "drm/i915: Prevent zero length "index" write" has been added to the 3.18-stable tree To: ville.syrjala@linux.intel.com, chris@chris-wilson.co.uk, daniel.vetter@ffwll.ch, djkurtz@chromium.org, gregkh@linuxfoundation.org, joonas.lahtinen@linux.intel.com, seanpaul@chromium.org Cc: , From: Date: Mon, 04 Dec 2017 14:59:35 +0100 Message-ID: <151239597542200@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled drm/i915: Prevent zero length "index" write to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-i915-prevent-zero-length-index-write.patch and it can be found in the queue-3.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 56350fb8978bbf4aafe08f21234e161dd128b417 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Thu, 23 Nov 2017 21:41:57 +0200 Subject: drm/i915: Prevent zero length "index" write MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Ville Syrjälä commit 56350fb8978bbf4aafe08f21234e161dd128b417 upstream. The hardware always writes one or two bytes in the index portion of an indexed transfer. Make sure the message we send as the index doesn't have a zero length. Cc: Daniel Kurtz Cc: Chris Wilson Cc: Daniel Vetter Cc: Sean Paul Fixes: 56f9eac05489 ("drm/i915/intel_i2c: use INDEX cycles for i2c read transactions") Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20171123194157.25367-3-ville.syrjala@linux.intel.com Reviewed-by: Chris Wilson (cherry picked from commit bb9e0d4bca50f429152e74a459160b41f3d60fb2) Signed-off-by: Joonas Lahtinen Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_i2c.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/i915/intel_i2c.c +++ b/drivers/gpu/drm/i915/intel_i2c.c @@ -395,7 +395,8 @@ gmbus_is_index_read(struct i2c_msg *msgs { return (i + 1 < num && msgs[i].addr == msgs[i + 1].addr && - !(msgs[i].flags & I2C_M_RD) && msgs[i].len <= 2 && + !(msgs[i].flags & I2C_M_RD) && + (msgs[i].len == 1 || msgs[i].len == 2) && (msgs[i + 1].flags & I2C_M_RD)); } Patches currently in stable-queue which might be from ville.syrjala@linux.intel.com are queue-3.18/drm-i915-prevent-zero-length-index-write.patch queue-3.18/drm-i915-don-t-try-indexed-reads-to-alternate-slave-addresses.patch