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 <[email protected]> --- kernel/sched/rt.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index e4f398ad9e73..aa7ee3a0bf90 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2555,6 +2555,8 @@ 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); } @@ -2575,6 +2577,9 @@ 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;
