From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:37683 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752377AbeCZSIf (ORCPT ); Mon, 26 Mar 2018 14:08:35 -0400 Received: by mail-pf0-f194.google.com with SMTP id t16so3610424pfh.4 for ; Mon, 26 Mar 2018 11:08:35 -0700 (PDT) From: tskd08@gmail.com To: linux-media@vger.kernel.org Cc: mchehab@s-opensource.com, Akihiro Tsukada Subject: [PATCH v3 5/5] dvb-usb-v2/gl861: ensure USB message buffers DMA'able Date: Tue, 27 Mar 2018 03:06:52 +0900 Message-Id: <20180326180652.5385-6-tskd08@gmail.com> In-Reply-To: <20180326180652.5385-1-tskd08@gmail.com> References: <20180326180652.5385-1-tskd08@gmail.com> Sender: linux-media-owner@vger.kernel.org List-ID: From: Akihiro Tsukada i2c message buf might be on stack. Signed-off-by: Akihiro Tsukada --- drivers/media/usb/dvb-usb-v2/gl861.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/drivers/media/usb/dvb-usb-v2/gl861.c b/drivers/media/usb/dvb-usb-v2/gl861.c index a57afb12e84..4c29e0b417e 100644 --- a/drivers/media/usb/dvb-usb-v2/gl861.c +++ b/drivers/media/usb/dvb-usb-v2/gl861.c @@ -22,6 +22,8 @@ static int gl861_i2c_msg(struct dvb_usb_device *d, u8 addr, u16 value = addr << (8 + 1); int wo = (rbuf == NULL || rlen == 0); /* write-only */ u8 req, type; + u8 *buf; + int ret; if (wo) { req = GL861_REQ_I2C_WRITE; @@ -44,11 +46,23 @@ static int gl861_i2c_msg(struct dvb_usb_device *d, u8 addr, KBUILD_MODNAME, wlen); return -EINVAL; } - + buf = NULL; + if (rlen > 0) { + buf = kmalloc(rlen, GFP_KERNEL); + if (!buf) + return -ENOMEM; + } usleep_range(1000, 2000); /* avoid I2C errors */ - return usb_control_msg(d->udev, usb_rcvctrlpipe(d->udev, 0), req, type, - value, index, rbuf, rlen, 2000); + ret = usb_control_msg(d->udev, usb_rcvctrlpipe(d->udev, 0), req, type, + value, index, buf, rlen, 2000); + if (rlen > 0) { + if (ret > 0) + memcpy(rbuf, buf, rlen); + kfree(buf); + } + + return ret; } /* Friio specific I2C read/write */ -- 2.16.2