From patchwork Thu Apr 17 12:28:20 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ezequiel Garcia X-Patchwork-Id: 23660 X-Patchwork-Delegate: hverkuil@xs4all.nl Received: from mail.tu-berlin.de ([130.149.7.33]) by www.linuxtv.org with esmtp (Exim 4.72) (envelope-from ) id 1WalS4-0001LW-UP; Thu, 17 Apr 2014 14:30:00 +0200 X-tubIT-Incoming-IP: 209.132.180.67 Received: from vger.kernel.org ([209.132.180.67]) by mail.tu-berlin.de (exim-4.72/mailfrontend-8) with esmtp id 1WalS1-0005UX-le; Thu, 17 Apr 2014 14:30:00 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753639AbaDQM3X (ORCPT + 1 other); Thu, 17 Apr 2014 08:29:23 -0400 Received: from top.free-electrons.com ([176.31.233.9]:55479 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751335AbaDQM3W (ORCPT ); Thu, 17 Apr 2014 08:29:22 -0400 Received: by mail.free-electrons.com (Postfix, from userid 106) id 1BFEE7D9; Thu, 17 Apr 2014 14:29:23 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on mail.free-electrons.com X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,SHORTCIRCUIT shortcircuit=ham autolearn=disabled version=3.3.2 Received: from localhost.localdomain (unknown [190.2.108.30]) by mail.free-electrons.com (Postfix) with ESMTPSA id 6932E669; Thu, 17 Apr 2014 14:29:21 +0200 (CEST) From: Ezequiel Garcia To: Cc: Hans Verkuil , Ezequiel Garcia , Alan Stern Subject: [PATCH v2] media: stk1160: Avoid stack-allocated buffer for control URBs Date: Thu, 17 Apr 2014 09:28:20 -0300 Message-Id: <1397737700-1081-1-git-send-email-ezequiel.garcia@free-electrons.com> X-Mailer: git-send-email 1.9.1 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-PMX-Version: 6.0.0.2142326, Antispam-Engine: 2.7.2.2107409, Antispam-Data: 2014.4.17.122119 X-PMX-Spam: Gauge=IIIIIIII, Probability=8%, Report=' MULTIPLE_RCPTS 0.1, HTML_00_01 0.05, HTML_00_10 0.05, BODYTEXTP_SIZE_3000_LESS 0, BODY_SIZE_2000_2999 0, BODY_SIZE_5000_LESS 0, BODY_SIZE_7000_LESS 0, URI_ENDS_IN_HTML 0, __ANY_URI 0, __CP_URI_IN_BODY 0, __HAS_FROM 0, __HAS_MSGID 0, __HAS_X_MAILER 0, __HAS_X_MAILING_LIST 0, __MIME_TEXT_ONLY 0, __MULTIPLE_RCPTS_CC_X2 0, __SANE_MSGID 0, __SUBJ_ALPHA_END 0, __TO_MALFORMED_2 0, __TO_NO_NAME 0, __URI_NO_WWW 0, __URI_NS ' Currently stk1160_read_reg() uses a stack-allocated char to get the read control value. This is wrong because usb_control_msg() requires a kmalloc-ed buffer. This commit fixes such issue by kmalloc'ating a 1-byte buffer to receive the read value. While here, let's remove the urb_buf array which was meant for a similar purpose, but never really used. Cc: Alan Stern Reported-by: Sander Eikelenboom Signed-off-by: Ezequiel Garcia --- drivers/media/usb/stk1160/stk1160-core.c | 10 +++++++++- drivers/media/usb/stk1160/stk1160.h | 1 - 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/media/usb/stk1160/stk1160-core.c b/drivers/media/usb/stk1160/stk1160-core.c index 34a26e0..03504dc 100644 --- a/drivers/media/usb/stk1160/stk1160-core.c +++ b/drivers/media/usb/stk1160/stk1160-core.c @@ -67,17 +67,25 @@ int stk1160_read_reg(struct stk1160 *dev, u16 reg, u8 *value) { int ret; int pipe = usb_rcvctrlpipe(dev->udev, 0); + u8 *buf; *value = 0; + + buf = kmalloc(sizeof(u8), GFP_KERNEL); + if (!buf) + return -ENOMEM; ret = usb_control_msg(dev->udev, pipe, 0x00, USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE, - 0x00, reg, value, sizeof(u8), HZ); + 0x00, reg, buf, sizeof(u8), HZ); if (ret < 0) { stk1160_err("read failed on reg 0x%x (%d)\n", reg, ret); + kfree(buf); return ret; } + *value = *buf; + kfree(buf); return 0; } diff --git a/drivers/media/usb/stk1160/stk1160.h b/drivers/media/usb/stk1160/stk1160.h index 05b05b1..abdea48 100644 --- a/drivers/media/usb/stk1160/stk1160.h +++ b/drivers/media/usb/stk1160/stk1160.h @@ -143,7 +143,6 @@ struct stk1160 { int num_alt; struct stk1160_isoc_ctl isoc_ctl; - char urb_buf[255]; /* urb control msg buffer */ /* frame properties */ int width; /* current frame width */