From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751306AbdAVGni (ORCPT ); Sun, 22 Jan 2017 01:43:38 -0500 Received: from regular1.263xmail.com ([211.150.99.130]:52603 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750886AbdAVGnf (ORCPT ); Sun, 22 Jan 2017 01:43:35 -0500 X-263anti-spam: KSV:0; X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-RL-SENDER: zyw@rock-chips.com X-FST-TO: linux-kernel@vger.kernel.org X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: zyw@rock-chips.com X-UNIQUE-TAG: X-ATTACHMENT-NUM: 0 X-DNS-TYPE: 0 Subject: Re: [PATCH v2 07/26] drm/rockchip: dw-mipi-dsi: avoid out-of-bounds read on tx_buf To: John Keeping , Mark Yao References: <20170121163128.22240-1-john@metanate.com> <20170121163128.22240-8-john@metanate.com> Cc: dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org From: Chris Zhong Message-ID: <58845456.2040501@rock-chips.com> Date: Sun, 22 Jan 2017 14:42:30 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <20170121163128.22240-8-john@metanate.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi John Reviewed-by: Chris Zhong On 01/22/2017 12:31 AM, John Keeping wrote: > As a side-effect of this, encode the endianness explicitly rather than > casting a u16. > > Signed-off-by: John Keeping > --- > Unchanged in v2 > --- > drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c > index 4be1ff3a42bb..2e6ad4591ebf 100644 > --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c > +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c > @@ -572,8 +572,13 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val) > static int dw_mipi_dsi_dcs_short_write(struct dw_mipi_dsi *dsi, > const struct mipi_dsi_msg *msg) > { > - const u16 *tx_buf = msg->tx_buf; > - u32 val = GEN_HDATA(*tx_buf) | GEN_HTYPE(msg->type); > + const u8 *tx_buf = msg->tx_buf; > + u32 val = GEN_HTYPE(msg->type); > + > + if (msg->tx_len > 0) > + val |= GEN_HDATA(tx_buf[0]); > + if (msg->tx_len > 1) > + val |= GEN_HDATA(tx_buf[1] << 8); > > if (msg->tx_len > 2) { > dev_err(dsi->dev, "too long tx buf length %zu for short write\n",