From: Frank Mori Hess <fmhess@users.sourceforge.net>
Date: Mon, 15 Dec 2008 13:48:47 +0000 (+0000)
Subject: Staging: comedi: fix bug with invalid minor number usage.
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=53b670a75bef4bf6484bbf6ca6a896c365676fd4;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

Staging: comedi: fix bug with invalid minor number usage.

Return error instead of segfaulting if user trys to run comedi_config on
a device file with and invalid minor number.

From: Frank Mori Hess <fmhess@users.sourceforge.net>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: David Schleef <ds@schleef.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index 1464f550a5af..fbd3d1c6c647 100644
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -104,9 +104,13 @@ static int comedi_ioctl(struct inode *inode, struct file *file,
 	const unsigned minor = iminor(file->f_dentry->d_inode);
 	struct comedi_device_file_info *dev_file_info =
 	    comedi_get_device_file_info(minor);
-	comedi_device *dev = dev_file_info->device;
+	comedi_device *dev;
 	int rc;
 
+	if (dev_file_info == NULL || dev_file_info->device == NULL)
+		return -ENODEV;
+	dev = dev_file_info->device;
+
 	mutex_lock(&dev->mutex);
 
 	/* Device config is special, because it must work on