[runtime] Fix a hazard pointer leakage in mono_thread_info_resume.

mono_thread_info_lookup leaves the current value on hazard pointer 1,
so all callers must clean it afterwards. This was not done in all cases
by mono_thread_info_resume.

diff --git a/mono/utils/mono-threads.c b/mono/utils/mono-threads.c
index 60615489783ef972cccd5c6c6782e7c05ec29149..0b8bb13375bd838b8f0683713e22e60f5c1e4d16 100644 (file)
--- a/mono/utils/mono-threads.c
+++ b/mono/utils/mono-threads.c
@@ -444,18 +444,21 @@ mono_thread_info_resume_internal (MonoThreadInfo *info)
 gboolean
 mono_thread_info_resume (MonoNativeThreadId tid)
 {
-       gboolean result = TRUE;
+       gboolean result; /* don't initialize it so the compiler can catch unitilized paths. */
        MonoThreadHazardPointers *hp = mono_hazard_pointer_get ();      
        MonoThreadInfo *info = mono_thread_info_lookup (tid); /*info on HP1*/
 
-       if (!info)
-               return FALSE;
+       if (!info) {
+               result = FALSE;
+               goto cleanup;
+       }
 
        if (info->create_suspended) {
                /* Have to special case this, as the normal suspend/resume pair are racy, they don't work if he resume is received before the suspend */
                info->create_suspended = FALSE;
                mono_threads_core_resume_created (info, tid);
-               return TRUE;
+               result = TRUE;
+               goto cleanup;
        }
 
        MONO_SEM_WAIT_UNITERRUPTIBLE (&info->suspend_semaphore);
@@ -464,8 +467,8 @@ mono_thread_info_resume (MonoNativeThreadId tid)
 
        if (info->suspend_count <= 0) {
                MONO_SEM_POST (&info->suspend_semaphore);
-               mono_hazard_pointer_clear (hp, 1);
-               return FALSE;
+               result = FALSE;
+               goto cleanup;
        }
 
        /*
@@ -476,11 +479,14 @@ mono_thread_info_resume (MonoNativeThreadId tid)
 
        if (--info->suspend_count == 0)
                result = mono_thread_info_resume_internal (info);
+       else
+               result = TRUE;
 
        MONO_SEM_POST (&info->suspend_semaphore);
-       mono_hazard_pointer_clear (hp, 1);
        mono_atomic_store_release (&mono_thread_info_current ()->inside_critical_region, FALSE);
 
+cleanup:
+       mono_hazard_pointer_clear (hp, 1);
        return result;
 }