From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 07 Jan 2015 11:04:21 +0000
Subject: [patch] [media] gspca: underflow in vidioc_s_parm()
Message-Id: <20150107110421.GB14864@mwanda>
List-Id: <kernel-janitors.vger.kernel.org>
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To: Hans de Goede <hdegoede@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>, linux-media@vger.kernel.org, kernel-janitors@vger.kernel.org

"n" is a user controlled integer.  The code here doesn't handle the case
where "n" is negative and this causes a static checker warning.

	drivers/media/usb/gspca/gspca.c:1571 vidioc_s_parm()
	warn: no lower bound on 'n'

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
I haven't followed through to see if this is a real problem.

diff --git a/drivers/media/usb/gspca/gspca.c b/drivers/media/usb/gspca/gspca.c
index 43d6505..27f7da1 100644
--- a/drivers/media/usb/gspca/gspca.c
+++ b/drivers/media/usb/gspca/gspca.c
@@ -1565,6 +1565,8 @@ static int vidioc_s_parm(struct file *filp, void *priv,
 	int n;
 
 	n = parm->parm.capture.readbuffers;
+	if (n < 0)
+		return -EINVAL;
 	if (n = 0 || n >= GSPCA_MAX_FRAMES)
 		parm->parm.capture.readbuffers = gspca_dev->nbufread;
 	else