From d33fdd86a3de75500fe554d6547cf5ad43e006bf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=C3=A3o=20Oliveira?= <hello@jxs.pt>
Date: Thu, 25 Apr 2024 08:02:11 +0100
Subject: [PATCH] time: check for overflow in `Interval::poll_tick` (#6487)

---
 tokio/src/time/interval.rs   | 4 +++-
 tokio/tests/time_interval.rs | 8 +++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/tokio/src/time/interval.rs b/tokio/src/time/interval.rs
index dee28793a32..2b5246acfa4 100644
--- a/tokio/src/time/interval.rs
+++ b/tokio/src/time/interval.rs
@@ -480,7 +480,9 @@ impl Interval {
             self.missed_tick_behavior
                 .next_timeout(timeout, now, self.period)
         } else {
-            timeout + self.period
+            timeout
+                .checked_add(self.period)
+                .unwrap_or_else(Instant::far_future)
         };
 
         // When we arrive here, the internal delay returned `Poll::Ready`.
diff --git a/tokio/tests/time_interval.rs b/tokio/tests/time_interval.rs
index 4f3e95b0d2a..7472a37123c 100644
--- a/tokio/tests/time_interval.rs
+++ b/tokio/tests/time_interval.rs
@@ -6,7 +6,7 @@ use std::task::{Context, Poll};
 
 use futures::{Stream, StreamExt};
 use tokio::time::{self, Duration, Instant, Interval, MissedTickBehavior};
-use tokio_test::{assert_pending, assert_ready_eq, task};
+use tokio_test::{assert_pending, assert_ready, assert_ready_eq, task};
 
 // Takes the `Interval` task, `start` variable, and optional time deltas
 // For each time delta, it polls the `Interval` and asserts that the result is
@@ -469,3 +469,9 @@ async fn stream_with_interval_poll_tick_no_waking() {
     // task when returning `Poll::Ready`.
     assert_eq!(items, vec![]);
 }
+
+#[tokio::test(start_paused = true)]
+async fn interval_doesnt_panic_max_duration_when_polling() {
+    let mut timer = task::spawn(time::interval(Duration::MAX));
+    assert_ready!(timer.enter(|cx, mut timer| timer.poll_tick(cx)));
+}