From e18f110107399803dd070088c601f9a5540a2a3f Mon Sep 17 00:00:00 2001
From: Hidehiko Abe <hidehiko@chromium.org>
Date: Thu, 3 Oct 2019 02:04:53 +0900
Subject: [PATCH] components/timers: fix fd leak in AlarmTimer

This is fixed upstream but will take a while to roll back
into Chrome OS.

BUG=chromium:984593
TEST=enable/disable wifi repeatedly and see that there is no
     growth of open timerfds

Change-Id: If2af8f8ddf6b9dc31cda36fe5f5454ca0c5819de
---
 components/timers/alarm_timer_chromeos.cc |  8 ++++----
 components/timers/alarm_timer_chromeos.h  | 15 ++++++++-------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/components/timers/alarm_timer_chromeos.cc b/components/timers/alarm_timer_chromeos.cc
index 0b43134..f14d889 100644
--- a/components/timers/alarm_timer_chromeos.cc
+++ b/components/timers/alarm_timer_chromeos.cc
@@ -80,7 +80,7 @@ void SimpleAlarmTimer::Reset() {
   alarm_time.it_value.tv_nsec =
       (delay.InMicroseconds() % base::Time::kMicrosecondsPerSecond) *
       base::Time::kNanosecondsPerMicrosecond;
-  if (timerfd_settime(alarm_fd_, 0, &alarm_time, NULL) < 0)
+  if (timerfd_settime(alarm_fd_.get(), 0, &alarm_time, NULL) < 0)
     PLOG(ERROR) << "Error while setting alarm time.  Timer will not fire";
 
   // The timer is running.
@@ -97,7 +97,7 @@ void SimpleAlarmTimer::Reset() {
     base::debug::TaskAnnotator().WillQueueTask("SimpleAlarmTimer::Reset",
                                                pending_task_.get());
     alarm_fd_watcher_ = base::FileDescriptorWatcher::WatchReadable(
-        alarm_fd_,
+        alarm_fd_.get(),
         base::BindRepeating(&SimpleAlarmTimer::OnAlarmFdReadableWithoutBlocking,
                             weak_factory_.GetWeakPtr()));
   }
@@ -109,7 +109,7 @@ void SimpleAlarmTimer::OnAlarmFdReadableWithoutBlocking() {
 
   // Read from |alarm_fd_| to ack the event.
   char val[sizeof(uint64_t)];
-  if (!base::ReadFromFD(alarm_fd_, val, sizeof(uint64_t)))
+  if (!base::ReadFromFD(alarm_fd_.get(), val, sizeof(uint64_t)))
     PLOG(DFATAL) << "Unable to read from timer file descriptor.";
 
   OnTimerFired();
@@ -137,7 +137,7 @@ void SimpleAlarmTimer::OnTimerFired() {
 }
 
 bool SimpleAlarmTimer::CanWakeFromSuspend() const {
-  return alarm_fd_ != -1;
+  return alarm_fd_.is_valid();
 }
 
 }  // namespace timers
diff --git a/components/timers/alarm_timer_chromeos.h b/components/timers/alarm_timer_chromeos.h
index 1ff689e..100ba81 100644
--- a/components/timers/alarm_timer_chromeos.h
+++ b/components/timers/alarm_timer_chromeos.h
@@ -8,6 +8,7 @@
 #include <memory>
 
 #include "base/files/file_descriptor_watcher_posix.h"
+#include "base/files/scoped_file.h"
 #include "base/macros.h"
 #include "base/memory/scoped_refptr.h"
 #include "base/memory/weak_ptr.h"
@@ -43,6 +44,12 @@ class SimpleAlarmTimer : public base::RetainingOneShotTimer {
   void Stop() override;
   void Reset() override;
 
+  // Tracks whether the timer has the ability to wake the system up from
+  // suspend. This is a runtime check because we won't know if the system
+  // supports being woken up from suspend until the constructor actually tries
+  // to set it up.
+  bool CanWakeFromSuspend() const;
+
  private:
   // Called when |alarm_fd_| is readable without blocking. Reads data from
   // |alarm_fd_| and calls OnTimerFired().
@@ -51,14 +58,8 @@ class SimpleAlarmTimer : public base::RetainingOneShotTimer {
   // Called when the timer fires. Runs the callback.
   void OnTimerFired();
 
-  // Tracks whether the timer has the ability to wake the system up from
-  // suspend. This is a runtime check because we won't know if the system
-  // supports being woken up from suspend until the constructor actually tries
-  // to set it up.
-  bool CanWakeFromSuspend() const;
-
   // Timer file descriptor.
-  const int alarm_fd_;
+  base::ScopedFD alarm_fd_;
 
   // Watches |alarm_fd_|.
   std::unique_ptr<base::FileDescriptorWatcher::Controller> alarm_fd_watcher_;
-- 
2.23.0.581.g78d2f28ef7-goog