[PATCH 3.2 84/87] [media] usbvision-video: fix memory leak of alt_max_pkt_size

From: Ben Hutchings
Date: Mon Feb 08 2016 - 19:22:00 EST


3.2.77-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/media/video/usbvision/usbvision-video.c | 2 ++
1 file changed, 2 insertions(+)

--- 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_remove_sysfs(usbvision->vdev);
usbvision_unregister_video(usbvision);
+ kfree(usbvision->alt_max_pkt_size);

usb_free_urb(usbvision->ctrl_urb);

@@ -1540,6 +1541,7 @@ static int __devinit usbvision_probe(str
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;
}