3.16.74-rc1 review patch. If anyone has any objections, please let me know.
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From: Oliver Neukum <oneukum@xxxxxxxx>
commit eff73de2b1600ad8230692f00bc0ab49b166512a upstream.
Kasan reported a use after free in cpia2_usb_disconnect()
It first freed everything and then woke up those waiting.
The reverse order is correct.
Fixes: 6c493f8b28c67 ("[media] cpia2: major overhaul to get it in a working state again")
Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx>
Reported-by: syzbot+0c90fc937c84f97d0aa6@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/media/usb/cpia2/cpia2_usb.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/media/usb/cpia2/cpia2_usb.c
+++ b/drivers/media/usb/cpia2/cpia2_usb.c
@@ -884,7 +884,6 @@ static void cpia2_usb_disconnect(struct
cpia2_unregister_camera(cam);
v4l2_device_disconnect(&cam->v4l2_dev);
mutex_unlock(&cam->v4l2_lock);
- v4l2_device_put(&cam->v4l2_dev);
if(cam->buffers) {
DBG("Wakeup waiting processes\n");
@@ -897,6 +896,8 @@ static void cpia2_usb_disconnect(struct
DBG("Releasing interface\n");
usb_driver_release_interface(&cpia2_driver, intf);
+ v4l2_device_put(&cam->v4l2_dev);
+
LOG("CPiA2 camera disconnected.\n");
}
