From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ppsw-50.csi.cam.ac.uk ([131.111.8.150]:59268 "EHLO ppsw-50.csi.cam.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753674Ab1HZJMT (ORCPT ); Fri, 26 Aug 2011 05:12:19 -0400 Message-ID: <4E57655D.4060303@cam.ac.uk> Date: Fri, 26 Aug 2011 10:20:29 +0100 From: Jonathan Cameron MIME-Version: 1.0 To: michael.hennerich@analog.com CC: linux-iio@vger.kernel.org, device-drivers-devel@blackfin.uclinux.org, drivers@analog.com Subject: Re: [PATCH] iio: imu: adis16400: Avoid null pointer dereference References: <1314348200-11112-1-git-send-email-michael.hennerich@analog.com> In-Reply-To: <1314348200-11112-1-git-send-email-michael.hennerich@analog.com> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 08/26/11 09:43, michael.hennerich@analog.com wrote: > From: Michael Hennerich > > Not sure if this is a proper fix. However it should do the trick. > ring->scan_maks is allocated in iio_ring_buffer_register() which called > after adis16400_configure_ring. So the time this pointer dereference takes > place scan_mask is uninitialized. Dratt missed that one. This definitely isn't the right fix as it will get wiped out when that element is initialized. Mostly I fixed equivalents elsewhere by not setting a default. After all user space shouldn't be relying on any particular set of channels being enable anyway. Do we have a good reason to not just remove it here? > > Signed-off-by: Michael Hennerich > --- > drivers/staging/iio/imu/adis16400_ring.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/staging/iio/imu/adis16400_ring.c b/drivers/staging/iio/imu/adis16400_ring.c > index 1a47d07..f6d50be 100644 > --- a/drivers/staging/iio/imu/adis16400_ring.c > +++ b/drivers/staging/iio/imu/adis16400_ring.c > @@ -191,7 +191,7 @@ int adis16400_configure_ring(struct iio_dev *indio_dev) > ring->setup_ops = &adis16400_ring_setup_ops; > ring->owner = THIS_MODULE; > /* Set default scan mode - assumes single long is big enough */ > - *ring->scan_mask = st->variant->default_scan_mask; > + ring->scan_mask = &st->variant->default_scan_mask; > ring->scan_count = hweight_long(st->variant->default_scan_mask); > > indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,