From 39c753733bafec210dc9d298662dd9be736a9ac1 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Mon, 29 Jul 2019 18:33:10 -0700 Subject: [PATCH 0084/2944] sched/psi: Do not require setsched permission from the trigger creator commit 04e048cf09d7b5fc995817cdc5ae1acd4482429c upstream. When a process creates a new trigger by writing into /proc/pressure/* files, permissions to write such a file should be used to determine whether the process is allowed to do so or not. Current implementation would also require such a process to have setsched capability. Setting of psi trigger thread's scheduling policy is an implementation detail and should not be exposed to the user level. Remove the permission check by using _nocheck version of the function. Suggested-by: Nick Kralevich Signed-off-by: Suren Baghdasaryan Signed-off-by: Peter Zijlstra (Intel) Cc: lizefan@huawei.com Cc: mingo@redhat.com Cc: akpm@linux-foundation.org Cc: kernel-team@android.com Cc: dennisszhou@gmail.com Cc: dennis@kernel.org Cc: hannes@cmpxchg.org Cc: axboe@kernel.dk Link: https://lkml.kernel.org/r/20190730013310.162367-1-surenb@google.com Signed-off-by: Joseph Qi Acked-by: Caspar Zhang --- kernel/sched/psi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index 1f2fbbe..6e52b67 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -1061,7 +1061,7 @@ struct psi_trigger *psi_trigger_create(struct psi_group *group, mutex_unlock(&group->trigger_lock); return ERR_CAST(kworker); } - sched_setscheduler(kworker->task, SCHED_FIFO, ¶m); + sched_setscheduler_nocheck(kworker->task, SCHED_FIFO, ¶m); kthread_init_delayed_work(&group->poll_work, psi_poll_work); rcu_assign_pointer(group->poll_kworker, kworker); -- 1.8.3.1