From patchwork Tue Nov 5 10:01:30 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 3142321 Return-Path: X-Original-To: patchwork-linux-media@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 8A7E39F440 for ; Tue, 5 Nov 2013 15:11:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5023520430 for ; Tue, 5 Nov 2013 15:11:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 41C0B203E6 for ; Tue, 5 Nov 2013 15:11:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751263Ab3KEPLw (ORCPT ); Tue, 5 Nov 2013 10:11:52 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:43792 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751009Ab3KEPLw (ORCPT ); Tue, 5 Nov 2013 10:11:52 -0500 Received: from [177.143.133.66] (helo=smtp.w2.samsung.com) by bombadil.infradead.org with esmtpsa (Exim 4.80.1 #2 (Red Hat Linux)) id 1VdiIH-0004Ii-O8; Tue, 05 Nov 2013 15:11:49 +0000 Received: from mchehab by smtp.w2.samsung.com with local (Exim 4.80.1) (envelope-from ) id 1VddSC-00080A-Cu; Tue, 05 Nov 2013 08:01:44 -0200 From: Mauro Carvalho Chehab Cc: Mauro Carvalho Chehab , Linux Media Mailing List , Mauro Carvalho Chehab Subject: [PATCH v3 17/29] [media] av7110_hw: Don't use dynamic static allocation Date: Tue, 5 Nov 2013 08:01:30 -0200 Message-Id: <1383645702-30636-18-git-send-email-m.chehab@samsung.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1383645702-30636-1-git-send-email-m.chehab@samsung.com> References: <1383645702-30636-1-git-send-email-m.chehab@samsung.com> To: unlisted-recipients:; (no To-header on input) Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Dynamic static allocation is evil, as Kernel stack is too low, and compilation complains about it on some archs: drivers/media/pci/ttpci/av7110_hw.c:510:1: warning: 'av7110_fw_cmd' uses dynamic stack allocation [enabled by default] Instead, let's enforce a limit for the buffer. In the specific case of this driver, the maximum fw command size is 6 + 2, as checked using: $ git grep -A1 av7110_fw_cmd drivers/media/pci/ttpci/ So, use 8 for the buffer size. Signed-off-by: Mauro Carvalho Chehab --- drivers/media/pci/ttpci/av7110_hw.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/media/pci/ttpci/av7110_hw.c b/drivers/media/pci/ttpci/av7110_hw.c index f1cbfe526989..6299d5dadb82 100644 --- a/drivers/media/pci/ttpci/av7110_hw.c +++ b/drivers/media/pci/ttpci/av7110_hw.c @@ -22,7 +22,7 @@ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * Or, point your browser to http://www.gnu.org/copyleft/gpl.html * - * the project's page is at http://www.linuxtv.org/ + * the project's page is at http://www.linuxtv.org/ */ /* for debugging ARM communication: */ @@ -40,6 +40,14 @@ #define _NOHANDSHAKE +/* + * Max transfer size done by av7110_fw_cmd() + * + * The maximum size passed to this function is 6 bytes. The buffer also + * uses two additional ones for type and size. So, 8 bytes is enough. + */ +#define MAX_XFER_SIZE 8 + /**************************************************************************** * DEBI functions ****************************************************************************/ @@ -488,11 +496,18 @@ static int av7110_send_fw_cmd(struct av7110 *av7110, u16* buf, int length) int av7110_fw_cmd(struct av7110 *av7110, int type, int com, int num, ...) { va_list args; - u16 buf[num + 2]; + u16 buf[MAX_XFER_SIZE]; int i, ret; // dprintk(4, "%p\n", av7110); + if (2 + num > sizeof(buf)) { + printk(KERN_WARNING + "%s: %s len=%d is too big!\n", + KBUILD_MODNAME, __func__, num); + return -EINVAL; + } + buf[0] = ((type << 8) | com); buf[1] = num;