From: Dan Carpenter <dan.carpenter@oracle.com> commit b7db58105b80fa9232719c8329b995b3addfab55 upstream. 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@oracle.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Vaibhav Agarwal <vaibhav.sr@gmail.com> Link: https://lore.kernel.org/r/20200205123217.jreendkyxulqsool@kili.mountain Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- 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 d44b070..0f5c68e 100644 --- a/drivers/staging/greybus/audio_manager.c +++ b/drivers/staging/greybus/audio_manager.c @@ -89,8 +89,8 @@ 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); -- 1.8.3