From 50186044242b193811191fae34c1dae0c35c83b5 Mon Sep 17 00:00:00 2001
From: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Date: Wed, 27 Feb 2019 11:10:20 +0300
Subject: [PATCH] sched/core: Check quota and period overflow at usec to nsec
conversion
References: git fixes
Patch-mainline: v5.2-rc1
Git-commit: 1a8b4540db732ca16c9e43ac7c08b1b8f0b252d8
Large values could overflow u64 and pass following sanity checks.
# echo 18446744073750000 > cpu.cfs_period_us
# cat cpu.cfs_period_us
40448
# echo 18446744073750000 > cpu.cfs_quota_us
# cat cpu.cfs_quota_us
40448
After this patch they will fail with -EINVAL.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/155125502079.293431.3947497929372138600.stgit@buzz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
kernel/sched/core.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index e7382e8d094d..dec420fefa87 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7141,8 +7141,10 @@ int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us)
period = ktime_to_ns(tg->cfs_bandwidth.period);
if (cfs_quota_us < 0)
quota = RUNTIME_INF;
- else
+ else if ((u64)cfs_quota_us <= U64_MAX / NSEC_PER_USEC)
quota = (u64)cfs_quota_us * NSEC_PER_USEC;
+ else
+ return -EINVAL;
return tg_set_cfs_bandwidth(tg, period, quota);
}
@@ -7164,6 +7166,9 @@ int tg_set_cfs_period(struct task_group *tg, long cfs_period_us)
{
u64 quota, period;
+ if ((u64)cfs_period_us > U64_MAX / NSEC_PER_USEC)
+ return -EINVAL;
+
period = (u64)cfs_period_us * NSEC_PER_USEC;
quota = tg->cfs_bandwidth.quota;