[PATCH] quartz: Increment reference count for the advise thread to avoid crashes caused by DLL unloading.

Hiroki Awata castaneai at by.black
Tue Aug 10 17:38:25 CDT 2021

Some games crash when the DLL is unloaded during SleepConditionVariableCS on SystemClockAdviseThread.
This is due to the fact that DllCanUnloadNow returns S_OK even though the advise thread is running.
Incrementing the reference count when creating the advise thread resolves it.

Signed-off-by: Hiroki Awata <castaneai at by.black>
 dlls/quartz/systemclock.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/dlls/quartz/systemclock.c b/dlls/quartz/systemclock.c
index 73a923a7b99..7302de0e58f 100644
--- a/dlls/quartz/systemclock.c
+++ b/dlls/quartz/systemclock.c
@@ -104,6 +104,7 @@ static ULONG WINAPI system_clock_inner_Release(IUnknown *iface)
             WaitForSingleObject(clock->thread, INFINITE);
+            InterlockedDecrement(&object_locks);
         LIST_FOR_EACH_ENTRY_SAFE(sink, cursor, &clock->sinks, struct advise_sink, entry)
@@ -207,6 +208,8 @@ static HRESULT add_sink(struct system_clock *clock, DWORD_PTR handle,
     if (!InterlockedCompareExchange(&clock->thread_created, TRUE, FALSE))
         clock->thread = CreateThread(NULL, 0, SystemClockAdviseThread, clock, 0, NULL);
+        if (clock->thread)
+            InterlockedIncrement(&object_locks);

More information about the wine-devel mailing list