From patchwork Fri Feb 24 12:54:49 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Keeping X-Patchwork-Id: 9590169 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1AA73601AE for ; Fri, 24 Feb 2017 13:04:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D1AA528753 for ; Fri, 24 Feb 2017 13:04:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C61FE2875C; Fri, 24 Feb 2017 13:04:14 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 54D1728753 for ; Fri, 24 Feb 2017 13:04:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=y26BrubLm+oDRQ0o4Zis2EAE+Y0nY2aQ7G2xVwNJNeE=; b=FpcMQVRqYqilehdFP57JwYWmxP mQDUX4hzPPR4yzD3EerOToGCRoXnbg+JfNKcsD3vIkLheq7L5BJdTg9fZbzxxyXiOCnKvqdGaXzjN xkHcMatnkOgOTzOGL7HVP3PB3LQSFq1vm4hl17SKmVNcosT4b1SLp7ISg9Jp3/+bATLQL4aG/yauY HU4HuDhV/KUH0HnT0vfd3ov3mvEfFP/XYqSIBjUPwJAXGGPZBw0j/PAAdhtHgiQTjUFtPc0IYj1OL U+egCH7RlfXojz8jeQzx9hQh0hDQlXcm9+/PrF7qhEgLdwpGQ6u8Z/1XuA2emnk4MxCy3Qww/IQ0b KZ4Nb6xw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1chFXf-0004Hw-Jj; Fri, 24 Feb 2017 13:04:11 +0000 Received: from dougal.metanate.com ([90.155.101.14] helo=metanate.com) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1chFPY-0006Qv-Il; Fri, 24 Feb 2017 12:55:54 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=simple/simple; d=metanate.com; s=stronger; h=References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=tnIfQkhvSgsEcltGPVjwDjRrUCAbUMaBZTFuqlMa31I=; b=RhkgCDhcMSpJrKXxHPmyZHqzWGLTQwsHYUHpUnhntAqdeDM5uIX/R80mLyQVglReVZVumLttMe/h/mxTRNq/S3H/cPzoKO26jOv7Yyk/jmtJ+zZBT9rkg17pyxupVmTmSMjQMlRUmhVg8+Ds1oQRIPm5/gv8rEnWqvwSjP4Gum1TwF5m0mB4u8nHo0nnRdj/nzPS2UcKpdSG9o6E4mzXC0Xo+PJDVE5WgJ7tdnmeKH495rIcvIXqpIqfOo7Y6mToXJmKVNBpmfwLt8qt6raOl1svUShsjSKita1Rs1WNypG/fJ3N1DYXTBpFkVDEH+TFjtai9myZctDasB6SUvn4Bw==; Received: from brian ([192.168.88.1] helo=leela.metanate.com) by shrek.metanate.com with esmtpsa (TLSv1.2:DHE-RSA-AES128-GCM-SHA256:128) (Exim 4.83_RC2) (envelope-from ) id 1chFP0-0006ml-4j; Fri, 24 Feb 2017 12:55:14 +0000 From: John Keeping To: Mark Yao Subject: [PATCH v4 06/23] drm/rockchip: dw-mipi-dsi: avoid out-of-bounds read on tx_buf Date: Fri, 24 Feb 2017 12:54:49 +0000 Message-Id: <20170224125506.21533-7-john@metanate.com> X-Mailer: git-send-email 2.12.0.rc0.230.gf625d4cdb9.dirty In-Reply-To: <20170224125506.21533-1-john@metanate.com> References: <20170224125506.21533-1-john@metanate.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170224_045551_866357_B89399C5 X-CRM114-Status: UNSURE ( 8.29 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, Sean Paul , Chris Zhong , John Keeping , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP As a side-effect of this, encode the endianness explicitly rather than casting a u16. Signed-off-by: John Keeping --- v4: - Introduce "data" variable to avoid confusion around the masking in GEN_HDATA() v3: - Add Chris' Reviewed-by Unchanged in v2 --- drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 11 +++++++++-- 1 file changed, 9 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..f55010312f25 100644 --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c @@ -572,8 +572,14 @@ 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; + u16 data = 0; + u32 val; + + if (msg->tx_len > 0) + data |= tx_buf[0]; + if (msg->tx_len > 1) + data |= tx_buf[1] << 8; if (msg->tx_len > 2) { dev_err(dsi->dev, "too long tx buf length %zu for short write\n", @@ -581,6 +587,7 @@ static int dw_mipi_dsi_dcs_short_write(struct dw_mipi_dsi *dsi, return -EINVAL; } + val = GEN_HDATA(data) | GEN_HTYPE(msg->type); return dw_mipi_dsi_gen_pkt_hdr_write(dsi, val); }