[ Upstream commit 329101244f ]
The problem is in gb_lights_request_handler(). If we get a request to
change the config then we release the light with gb_lights_light_release()
and re-allocated it. However, if the allocation fails part way through
then we call gb_lights_light_release() again. This can lead to a couple
different double frees where we haven't cleared out the original values:
gb_lights_light_v4l2_unregister(light);
...
kfree(light->channels);
kfree(light->name);
I also made a small change to how we set "light->channels_count = 0;".
The original code handled this part fine and did not cause a use after
free but it was sort of complicated to read.
Fixes: 2870b52bae ("greybus: lights: add lights implementation")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Link: https://lore.kernel.org/r/20190829122839.GA20116@mwanda
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
8e456b4b1a