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| author | Konstantin Khlebnikov <khlebnikov@yandex-team.ru> | 2019-02-27 09:10:20 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2019-04-19 13:42:10 +0200 |
| commit | 1a8b4540db732ca16c9e43ac7c08b1b8f0b252d8 (patch) | |
| tree | 872de05aa4f62392f99ff31a4ac5c28bbdd0a9d6 | |
| parent | sched/core: Handle overflow in cpu_shares_write_u64 (diff) | |
| download | linux-1a8b4540db732ca16c9e43ac7c08b1b8f0b252d8.tar.xz linux-1a8b4540db732ca16c9e43ac7c08b1b8f0b252d8.zip | |
sched/core: Check quota and period overflow at usec to nsec conversion
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>
| -rw-r--r-- | kernel/sched/core.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 685b1541ce51..de8ab411826c 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6611,8 +6611,10 @@ static 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); } @@ -6634,6 +6636,9 @@ static 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; |