> We found a refcount UAF bug as follows: > > BUG: KASAN: use-after-free in cgroup_path_ns+0x112/0x150 … How do you think about to use a summary phrase like “Avoid use-after-free in proc_cpuset_show()”? > This is also reported by: https://syzkaller.appspot.com/bug?extid=9b1ff7be974a403aa4cd Would you like to add any tags (like “Fixes”) accordingly? … > +++ b/kernel/cgroup/cpuset.c … > @@ -5052,9 +5053,28 @@ int proc_cpuset_show(struct seq_file *m, struct pid_namespace *ns, > goto out; > > css = task_get_css(tsk, cpuset_cgrp_id); > + rcu_read_lock(); … > + rcu_read_unlock(); > retval = cgroup_path_ns(css->cgroup, buf, PATH_MAX, > current->nsproxy->cgroup_ns); … Would you become interested to apply a statement like “guard(rcu_read_lock)();”? https://elixir.bootlin.com/linux/v6.10-rc4/source/include/linux/cleanup.h#L133 Regards, Markus
