On 05-02-20, 15:32, Dan Carpenter wrote:
> When we call kobject_put() and it's the last reference to the kobject
> then it calls gb_audio_module_release() and frees module. We dereference
> "module" on the next line which is a use after free.
>
> Fixes: c77f85bbc91a ("greybus: audio: Fix incorrect counting of 'ida'")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> drivers/staging/greybus/audio_manager.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/staging/greybus/audio_manager.c b/drivers/staging/greybus/audio_manager.c
> index 9b19ea9d3fa1..9a3f7c034ab4 100644
> --- a/drivers/staging/greybus/audio_manager.c
> +++ b/drivers/staging/greybus/audio_manager.c
> @@ -92,8 +92,8 @@ void gb_audio_manager_remove_all(void)
>
> list_for_each_entry_safe(module, next, &modules_list, list) {
> list_del(&module->list);
> - kobject_put(&module->kobj);
> ida_simple_remove(&module_id, module->id);
> + kobject_put(&module->kobj);
> }
>
> is_empty = list_empty(&modules_list);
Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
--
viresh
