From: Alexey Khoroshilov <khoroshilov@ispras.ru>
Date: Wed, 27 Mar 2013 13:08:46 +0000 (+0100)
Subject: drbd: add module_put() on error path in drbd_proc_open()
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=193d01532a730a53cbc74462799dbc43968b97fd;p=openwrt%2Fstaging%2Fblogic.git

drbd: add module_put() on error path in drbd_proc_open()

If single_open() fails in drbd_proc_open(), module refcount is left incremented.
The patch adds module_put() on the error path.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/drivers/block/drbd/drbd_proc.c b/drivers/block/drbd/drbd_proc.c
index 56672a61eb94..30fe0a57f5a0 100644
--- a/drivers/block/drbd/drbd_proc.c
+++ b/drivers/block/drbd/drbd_proc.c
@@ -313,8 +313,14 @@ static int drbd_seq_show(struct seq_file *seq, void *v)
 
 static int drbd_proc_open(struct inode *inode, struct file *file)
 {
-	if (try_module_get(THIS_MODULE))
-		return single_open(file, drbd_seq_show, PDE(inode)->data);
+	int err;
+
+	if (try_module_get(THIS_MODULE)) {
+		err = single_open(file, drbd_seq_show, PDE(inode)->data);
+		if (err)
+			module_put(THIS_MODULE);
+		return err;
+	}
 	return -ENODEV;
 }