[ Upstream commit 1a010e29cfa00fee2888fd2fd4983f848cbafb58 ]
Example of unhandled overflows:
# echo 18446744073709651 > cpu.rt_runtime_us # cat cpu.rt_runtime_us 99
# echo 18446744073709900 > cpu.rt_period_us # cat cpu.rt_period_us 348
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/155125501739.293431.5252197504404771496.stgit@buzz Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/sched/rt.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index cb9a5b8532fa5..cc7dd1aaf08e3 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2533,6 +2533,8 @@ int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us) rt_runtime = (u64)rt_runtime_us * NSEC_PER_USEC; if (rt_runtime_us < 0) rt_runtime = RUNTIME_INF; + else if ((u64)rt_runtime_us > U64_MAX / NSEC_PER_USEC) + return -EINVAL;
return tg_set_rt_bandwidth(tg, rt_period, rt_runtime); } @@ -2553,6 +2555,9 @@ int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us) { u64 rt_runtime, rt_period;
+ if (rt_period_us > U64_MAX / NSEC_PER_USEC) + return -EINVAL; + rt_period = rt_period_us * NSEC_PER_USEC; rt_runtime = tg->rt_bandwidth.rt_runtime;