From: Andy Shevchenko <andy.shevchenko@gmail.com>
Date: Thu, 22 Jul 2010 08:58:47 +0000 (+0300)
Subject: usb: gadget: storage: strict coversion of 'ro' parameter
X-Git-Tag: firefly_0821_release~9833^2~1028^2~43
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=8156d158efa6370a8183f47327f122edbb4f2cb6;p=firefly-linux-kernel-4.4.55.git

usb: gadget: storage: strict coversion of 'ro' parameter

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 <ext-andriy.shevchenko@nokia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c
index a10faecfabcd..3bbddab72e57 100644
--- a/drivers/usb/gadget/storage_common.c
+++ b/drivers/usb/gadget/storage_common.c
@@ -748,9 +748,9 @@ 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;
 
 	/*
@@ -762,8 +762,8 @@ 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);