Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759489Ab0GVOHV (ORCPT ); Thu, 22 Jul 2010 10:07:21 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:33478 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1759370Ab0GVOHR (ORCPT ); Thu, 22 Jul 2010 10:07:17 -0400 Date: Thu, 22 Jul 2010 10:07:14 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Andy Shevchenko cc: linux-kernel@vger.kernel.org, Andy Shevchenko , David Brownell , Greg Kroah-Hartman , Subject: Re: [PATCHv4 1/2] usb: gadget: storage: strict coversion of 'ro' parameter In-Reply-To: <1279789128-11399-1-git-send-email-ext-andriy.shevchenko@nokia.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2541 Lines: 64 On Thu, 22 Jul 2010, Andy Shevchenko wrote: > Bring a strict way to get the 'ro' parameter from the user. > > The patch followed by this one adds another boolean parameter. To be consistent > Michał Nazarewicz proposed to use simple_strtol() in both cases (correspondend > discussion in LKML [1]). Due to simple_strtol() doesn't return error in a good > way and we have a boolean parameter the strict_strtoul() is used. > > [1] http://lkml.org/lkml/2010/7/14/169 > > Signed-off-by: Andy Shevchenko > Cc: Alan Stern > Cc: David Brownell > Cc: Greg Kroah-Hartman > Cc: linux-usb@vger.kernel.org > --- > drivers/usb/gadget/storage_common.c | 8 ++++---- > 1 files changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c > index 04c462f..7123929 100644 > --- a/drivers/usb/gadget/storage_common.c > +++ b/drivers/usb/gadget/storage_common.c > @@ -723,9 +723,9 @@ static ssize_t fsg_store_ro(struct device *dev, struct device_attribute *attr, > ssize_t rc = count; > struct fsg_lun *curlun = fsg_lun_from_dev(dev); > struct rw_semaphore *filesem = dev_get_drvdata(dev); > - int i; > + unsigned long ro; > > - if (sscanf(buf, "%d", &i) != 1) > + if (strict_strtoul(buf, 2, &ro)) > return -EINVAL; > > /* Allow the write-enable status to change only while the backing file > @@ -735,8 +735,8 @@ static ssize_t fsg_store_ro(struct device *dev, struct device_attribute *attr, > LDBG(curlun, "read-only status change prevented\n"); > rc = -EBUSY; > } else { > - curlun->ro = !!i; > - curlun->initially_ro = !!i; > + curlun->ro = ro; > + curlun->initially_ro = ro; > LDBG(curlun, "read-only status set to %d\n", curlun->ro); > } > up_read(filesem); Acked-by: Alan Stern Strictly speaking, this changes the behavior when a non-binary value is specified. For example, if somebody were to write "10" then the old code would set the value to True and the new code would set the value to False -- and neither would reject it as they probably should. That's okay; people who write ambiguous or invalid values deserve what they get. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/