On Wed, Aug 19, 2020 at 6:25 AM Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote: > > The bug in the existing code is that bpf_iter does get_file instead > of get_file_rcu. Does anyone have any sense of how to add debugging > to get_file to notice when it is being called in the wrong context? That bug is already fixed in bpf tree. See commit cf28f3bbfca0 ("bpf: Use get_file_rcu() instead of get_file() for task_file iterator")