usbvision-video: fix memory leak of alt_max_pkt_size

commit 090c65b694c362adb19ec9c27de216a808ee443c upstream.

1. usbvision->alt_max_pkt_size is not deallocated anywhere.
2. if allocation of usbvision->alt_max_pkt_size fails,
there is no proper deallocation of already acquired resources.
The patch adds kfree(usbvision->alt_max_pkt_size) to
usbvision_release() as soon as other deallocations happen there.
It calls usbvision_release() if allocation of
usbvision->alt_max_pkt_size fails as soon as usbvision_release()
is safe to work with incompletely initialized usbvision structure.
Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/media/video/usbvision/usbvision-video.c b/drivers/media/video/usbvision/usbvision-video.c
index 5a74f5e..9041dd4 100644 (file)
--- a/drivers/media/video/usbvision/usbvision-video.c
+++ b/drivers/media/video/usbvision/usbvision-video.c
@@ -1425,6 +1425,7 @@ static void usbvision_release(struct usb_usbvision *usbvision)
 
        usbvision_remove_sysfs(usbvision->vdev);
        usbvision_unregister_video(usbvision);
 
        usbvision_remove_sysfs(usbvision->vdev);
        usbvision_unregister_video(usbvision);

+       kfree(usbvision->alt_max_pkt_size);

 
        usb_free_urb(usbvision->ctrl_urb);
 
 
        usb_free_urb(usbvision->ctrl_urb);
 


@@ -1540,6 +1541,7 @@ static int __devinit usbvision_probe(struct usb_interface *intf,
        usbvision->alt_max_pkt_size = kmalloc(32 * usbvision->num_alt, GFP_KERNEL);
        if (usbvision->alt_max_pkt_size == NULL) {
                dev_err(&intf->dev, "usbvision: out of memory!\n");
        usbvision->alt_max_pkt_size = kmalloc(32 * usbvision->num_alt, GFP_KERNEL);
        if (usbvision->alt_max_pkt_size == NULL) {
                dev_err(&intf->dev, "usbvision: out of memory!\n");

+               usbvision_release(usbvision);

                return -ENOMEM;
        }
 
                return -ENOMEM;
        }