From 6dedde38214a277101a91e703131a7a846bc4cf5 Mon Sep 17 00:00:00 2001
From: Justin Link <jlink@mozilla.com>
Date: Fri, 23 May 2025 16:00:59 +0000
Subject: [PATCH] Bug 1925191: Don't create profiler markers for
 performance.measure() calls with timestamps that are too far in the future
 r=mstange

Differential Revision: https://phabricator.services.mozilla.com/D233309
---
 dom/performance/Performance.cpp | 46 +++++++++++++++++++++++----------
 dom/performance/Performance.h   |  5 ++--
 2 files changed, 34 insertions(+), 17 deletions(-)

diff --git a/dom/performance/Performance.cpp b/dom/performance/Performance.cpp
index 3bfda1dc6354..93792830a23a 100644
--- a/dom/performance/Performance.cpp
+++ b/dom/performance/Performance.cpp
@@ -590,22 +590,38 @@ static std::string GetMarkerFilename() {
   return s.str();
 }
 
-std::pair<TimeStamp, TimeStamp> Performance::GetTimeStampsForMarker(
+Maybe<std::pair<TimeStamp, TimeStamp>> Performance::GetTimeStampsForMarker(
     const Maybe<const nsAString&>& aStartMark,
     const Optional<nsAString>& aEndMark,
-    const Maybe<const PerformanceMeasureOptions&>& aOptions, ErrorResult& aRv) {
+    const Maybe<const PerformanceMeasureOptions&>& aOptions) {
+  ErrorResult err;
   const DOMHighResTimeStamp unclampedStartTime = ResolveStartTimeForMeasure(
-      aStartMark, aOptions, aRv, /* aReturnUnclamped */ true);
+      aStartMark, aOptions, err, /* aReturnUnclamped */ true);
   const DOMHighResTimeStamp unclampedEndTime =
-      ResolveEndTimeForMeasure(aEndMark, aOptions, aRv, /* aReturnUnclamped */
-                               true);
+      ResolveEndTimeForMeasure(aEndMark, aOptions, /* aReturnUnclamped */
+                               err, true);
+
+  if (err.Failed()) {
+    return Nothing();
+  }
+
+  // Performance.measure() can receive user-supplied timestamps and those
+  // timestamps might not be relative to 'navigation start'. This is
+  // (potentially) valid but, if we treat them as relative, we will end up
+  // placing them far into the future which causes problems for the profiler
+  // later so we report that as an error. (See bug 1925191 for details.)
+  // kMaxFuture_ms represents approximately 10 years worth of milliseconds.
+  static constexpr double kMaxFuture_ms = 31536000000.0;
+  if (unclampedStartTime > kMaxFuture_ms || unclampedEndTime > kMaxFuture_ms) {
+    return Nothing();
+  }
 
   TimeStamp startTimeStamp =
       CreationTimeStamp() + TimeDuration::FromMilliseconds(unclampedStartTime);
   TimeStamp endTimeStamp =
       CreationTimeStamp() + TimeDuration::FromMilliseconds(unclampedEndTime);
 
-  return std::make_pair(startTimeStamp, endTimeStamp);
+  return Some(std::make_pair(startTimeStamp, endTimeStamp));
 }
 
 // Try to open the marker file for writing performance markers.
@@ -679,13 +695,12 @@ void Performance::MaybeEmitExternalProfilerMarker(
   }
 
 #if defined(XP_LINUX) || defined(XP_WIN) || defined(XP_MACOSX)
-  ErrorResult rv;
-  auto [startTimeStamp, endTimeStamp] =
-      GetTimeStampsForMarker(aStartMark, aEndMark, aOptions, rv);
-
-  if (NS_WARN_IF(rv.Failed())) {
+  Maybe<std::pair<TimeStamp, TimeStamp>> tsPair =
+      GetTimeStampsForMarker(aStartMark, aEndMark, aOptions);
+  if (tsPair.isNothing()) {
     return;
   }
+  auto [startTimeStamp, endTimeStamp] = tsPair.value();
 #endif
 
 #ifdef XP_LINUX
@@ -728,9 +743,12 @@ void MOZ_NEVER_INLINE Performance::AddProfileMarker(
     const Maybe<const PerformanceMeasureOptions&>& options,
     const Maybe<const nsAString&>& aStartMark,
     const Optional<nsAString>& aEndMark) {
-  ErrorResult rv;
-  auto [startTimeStamp, endTimeStamp] =
-      GetTimeStampsForMarker(aStartMark, aEndMark, options, rv);
+  Maybe<std::pair<TimeStamp, TimeStamp>> tsPair =
+      GetTimeStampsForMarker(aStartMark, aEndMark, options);
+  if (tsPair.isNothing()) {
+    return;
+  }
+  auto [startTimeStamp, endTimeStamp] = tsPair.value();
 
   Maybe<nsString> endMark;
   if (aEndMark.WasPassed()) {
diff --git a/dom/performance/Performance.h b/dom/performance/Performance.h
index 8213fa8efad6..1e417dc2ae81 100644
--- a/dom/performance/Performance.h
+++ b/dom/performance/Performance.h
@@ -263,11 +263,10 @@ class Performance : public DOMEventTargetHelper {
       const Maybe<const PerformanceMeasureOptions&>& aOptions, ErrorResult& aRv,
       bool aReturnUnclamped);
 
-  std::pair<TimeStamp, TimeStamp> GetTimeStampsForMarker(
+  Maybe<std::pair<TimeStamp, TimeStamp>> GetTimeStampsForMarker(
       const Maybe<const nsAString&>& aStartMark,
       const Optional<nsAString>& aEndMark,
-      const Maybe<const PerformanceMeasureOptions&>& aOptions,
-      ErrorResult& aRv);
+      const Maybe<const PerformanceMeasureOptions&>& aOptions);
 };
 
 }  // namespace dom