[2.6.20.y PATCH 1/7] dvbdev: fix illegal re-usage of fileoperationsstruct

From: Michael Krufky
Date: Sat Mar 03 2007 - 09:37:25 EST


From: Marcel Siegert <mws@xxxxxxxxxxx>
Date: Tue, 27 Feb 2007 13:09:49 -0500
Subject: [PATCH] dvbdev: fix illegal re-usage of fileoperations struct

Arjan van de Ven <arjan@xxxxxxxxxxxxx> reported an illegal re-usage of
the fileoperations struct if more than one dvb device (e.g. frontend) is
present.

This patch fixes this issue.

It allocates a new fileoperations struct each time a device is
registered and copies the default template fileops.

Signed-off-by: Marcel Siegert <mws@xxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxx>
Signed-off-by: Michael Krufky <mkrufky@xxxxxxxxxxx>
(backported from commit b61901024776b25ce7b8edc31bb1757c7382a88e)
---
drivers/media/dvb/dvb-core/dvbdev.c | 13 +++++++++++++
1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/drivers/media/dvb/dvb-core/dvbdev.c b/drivers/media/dvb/dvb-core/dvbdev.c
index 40774fe..af35f30 100644
--- a/drivers/media/dvb/dvb-core/dvbdev.c
+++ b/drivers/media/dvb/dvb-core/dvbdev.c
@@ -200,6 +200,8 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
const struct dvb_device *template, void *priv, int type)
{
struct dvb_device *dvbdev;
+ struct file_operations *dvbdevfops;
+
int id;

if (mutex_lock_interruptible(&dvbdev_register_lock))
@@ -219,12 +221,22 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
return -ENOMEM;
}

+ dvbdevfops = kzalloc(sizeof(struct file_operations), GFP_KERNEL);
+
+ if (!dvbdevfops) {
+ kfree (dvbdev);
+ mutex_unlock(&dvbdev_register_lock);
+ return -ENOMEM;
+ }
+
memcpy(dvbdev, template, sizeof(struct dvb_device));
dvbdev->type = type;
dvbdev->id = id;
dvbdev->adapter = adap;
dvbdev->priv = priv;
+ dvbdev->fops = dvbdevfops;

+ memcpy(dvbdev->fops, template->fops, sizeof(struct file_operations));
dvbdev->fops->owner = adap->module;

list_add_tail (&dvbdev->list_head, &adap->device_list);
@@ -252,6 +264,7 @@ void dvb_unregister_device(struct dvb_device *dvbdev)
dvbdev->type, dvbdev->id)));

list_del (&dvbdev->list_head);
+ kfree (dvbdev->fops);
kfree (dvbdev);
}
EXPORT_SYMBOL(dvb_unregister_device);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/