From da8b001e96dca65fecf7769c6c0a276ca3448e2b Mon Sep 17 00:00:00 2001
From: Quentin Perret <qperret@google.com>
Date: Tue, 27 Jul 2021 11:11:02 +0100
Subject: [PATCH] sched: Don't report SCHED_FLAG_SUGOV in sched_getattr()

Patch-mainline: v5.15-rc1
References: bsc#1189999 (Scheduler functional and performance backports)
Git-commit: 7ad721bf10718a4e480a27ded8bb16b8f6feb2d1

SCHED_FLAG_SUGOV is supposed to be a kernel-only flag that userspace
cannot interact with. However, sched_getattr() currently reports it
in sched_flags if called on a sugov worker even though it is not
actually defined in a UAPI header. To avoid this, make sure to
clean-up the sched_flags field in sched_getattr() before returning to
userspace.

Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210727101103.2729607-3-qperret@google.com
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
 kernel/sched/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 61bad0835148..d1ed1fc2cca4 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7693,6 +7693,7 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
 		kattr.sched_priority = p->rt_priority;
 	else
 		kattr.sched_nice = task_nice(p);
+	kattr.sched_flags &= SCHED_FLAG_ALL;
 
 #ifdef CONFIG_UCLAMP_TASK
 	/*