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MID_RHS_MATCH_FROM(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; TAGGED_RCPT(0.00)[3d5461510f8dc4adfe30]; SUBJECT_HAS_QUESTION(0.00)[] X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Queue-Id: 0A379758E3 X-Spam-Score: -3.01 #syz test: upstream master diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 4438ecac9a89..d0e250d33ff0 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -626,6 +626,17 @@ static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer) return HRTIMER_NORESTART; } +/* + * Translate a stimer expiry given in 100ns reference ticks into an absolute + * deadline. Saturates on overflow. + */ +static ktime_t stimer_add_delta(ktime_t now, u64 delta_100ns) +{ + if (delta_100ns > KTIME_MAX / 100) + return KTIME_MAX; + return ktime_add_safe(now, 100 * delta_100ns); +} + /* * stimer_start() assumptions: * a) stimer->count is not equal to 0 @@ -635,6 +646,7 @@ static int stimer_start(struct kvm_vcpu_hv_stimer *stimer) { u64 time_now; ktime_t ktime_now; + ktime_t deadline; time_now = get_time_ref_counter(hv_stimer_to_vcpu(stimer)->kvm); ktime_now = ktime_get(); @@ -657,10 +669,8 @@ static int stimer_start(struct kvm_vcpu_hv_stimer *stimer) stimer->index, time_now, stimer->exp_time); - hrtimer_start(&stimer->timer, - ktime_add_ns(ktime_now, - 100 * (stimer->exp_time - time_now)), - HRTIMER_MODE_ABS); + deadline = stimer_add_delta(ktime_now, stimer->exp_time - time_now); + hrtimer_start(&stimer->timer, deadline, HRTIMER_MODE_ABS); return 0; } stimer->exp_time = stimer->count; @@ -679,9 +689,9 @@ static int stimer_start(struct kvm_vcpu_hv_stimer *stimer) stimer->index, time_now, stimer->count); - hrtimer_start(&stimer->timer, - ktime_add_ns(ktime_now, 100 * (stimer->count - time_now)), - HRTIMER_MODE_ABS); + deadline = stimer_add_delta(ktime_now, stimer->count - time_now); + hrtimer_start(&stimer->timer, deadline, HRTIMER_MODE_ABS); + return 0; }