From patchwork Fri Dec 6 12:57:32 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 297980 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 9EA682C00A6 for ; Sat, 7 Dec 2013 00:17:46 +1100 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1VovHp-0000XZ-Qo; Fri, 06 Dec 2013 13:17:41 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1Vov3k-0000mm-Fq for kernel-team@lists.ubuntu.com; Fri, 06 Dec 2013 13:03:08 +0000 Received: from bl20-223-32.dsl.telepac.pt ([2.81.223.32] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1Vov3k-0007nT-8u; Fri, 06 Dec 2013 13:03:08 +0000 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.11 163/272] [media] mxl111sf: Don't use dynamic static allocation Date: Fri, 6 Dec 2013 12:57:32 +0000 Message-Id: <1386334761-25517-164-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1386334761-25517-1-git-send-email-luis.henriques@canonical.com> References: <1386334761-25517-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Cc: Mauro Carvalho Chehab X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.11.10.1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mauro Carvalho Chehab commit c98300a0e8cf160aaea60bc05d2cd156a7666173 upstream. Dynamic static allocation is evil, as Kernel stack is too low, and compilation complains about it on some archs: drivers/media/usb/dvb-usb-v2/mxl111sf.c:74:1: warning: 'mxl111sf_ctrl_msg' uses dynamic stack allocation [enabled by default] Instead, let's enforce a limit for the buffer to be the max size of a control URB payload data (64 bytes). Signed-off-by: Mauro Carvalho Chehab Reviewed-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Luis Henriques --- drivers/media/usb/dvb-usb-v2/mxl111sf.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/media/usb/dvb-usb-v2/mxl111sf.c b/drivers/media/usb/dvb-usb-v2/mxl111sf.c index e97964e..2627553 100644 --- a/drivers/media/usb/dvb-usb-v2/mxl111sf.c +++ b/drivers/media/usb/dvb-usb-v2/mxl111sf.c @@ -23,6 +23,9 @@ #include "lgdt3305.h" #include "lg2160.h" +/* Max transfer size done by I2C transfer functions */ +#define MAX_XFER_SIZE 64 + int dvb_usb_mxl111sf_debug; module_param_named(debug, dvb_usb_mxl111sf_debug, int, 0644); MODULE_PARM_DESC(debug, "set debugging level " @@ -57,7 +60,12 @@ int mxl111sf_ctrl_msg(struct dvb_usb_device *d, { int wo = (rbuf == NULL || rlen == 0); /* write-only */ int ret; - u8 sndbuf[1+wlen]; + u8 sndbuf[MAX_XFER_SIZE]; + + if (1 + wlen > sizeof(sndbuf)) { + pr_warn("%s: len=%d is too big!\n", __func__, wlen); + return -EOPNOTSUPP; + } pr_debug("%s(wlen = %d, rlen = %d)\n", __func__, wlen, rlen);