[PATCH] programs/services: Add a 3000 ms timeout to StartService. (v2)

[Dmitry Timoshkov]

This patch avoids simultaneous services startup race and fixes bug 44904.

This version of the patch adds a timeout parameter to scmdatabase_lock_startup()
to make the approach more generic.

Please feel free to choose either old or new version of the patch.

Signed-off-by: Dmitry Timoshkov <dmitry at baikal.ru>
---
 programs/services/rpc.c      |  4 ++--
 programs/services/services.c | 15 ++++++++++++---
 programs/services/services.h |  2 +-
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/programs/services/rpc.c b/programs/services/rpc.c
index 5ecd6601a5..efbcd7645b 100644
--- a/programs/services/rpc.c
+++ b/programs/services/rpc.c
@@ -1212,7 +1212,7 @@ DWORD __cdecl svcctl_StartServiceW(
     if (service->service_entry->config.dwStartType == SERVICE_DISABLED)
         return ERROR_SERVICE_DISABLED;
 
-    if (!scmdatabase_lock_startup(service->service_entry->db))
+    if (!scmdatabase_lock_startup(service->service_entry->db, 3000))
         return ERROR_SERVICE_DATABASE_LOCKED;
 
     err = service_start(service->service_entry, dwNumServiceArgs, lpServiceArgVectors);
@@ -1374,7 +1374,7 @@ DWORD __cdecl svcctl_LockServiceDatabase(
     if ((err = validate_scm_handle(hSCManager, SC_MANAGER_LOCK, &manager)) != ERROR_SUCCESS)
         return err;
 
-    if (!scmdatabase_lock_startup(manager->db))
+    if (!scmdatabase_lock_startup(manager->db, 0))
         return ERROR_SERVICE_DATABASE_LOCKED;
 
     lock = HeapAlloc(GetProcessHeap(), 0, sizeof(struct sc_lock));
diff --git a/programs/services/services.c b/programs/services/services.c
index f7c47b5bc2..eba98d6ee8 100644
--- a/programs/services/services.c
+++ b/programs/services/services.c
@@ -361,7 +361,7 @@ static void scmdatabase_autostart_services(struct scmdatabase *db)
 
     scmdatabase_unlock(db);
     qsort(services_list, size, sizeof(services_list[0]), compare_tags);
-    while (!scmdatabase_lock_startup(db)) Sleep(10);
+    scmdatabase_lock_startup(db, INFINITE);
 
     for (i = 0; i < size; i++)
     {
@@ -619,9 +619,18 @@ static DWORD scmdatabase_load_services(struct scmdatabase *db)
     return ERROR_SUCCESS;
 }
 
-BOOL scmdatabase_lock_startup(struct scmdatabase *db)
+BOOL scmdatabase_lock_startup(struct scmdatabase *db, int timeout)
 {
-    return !InterlockedCompareExchange(&db->service_start_lock, TRUE, FALSE);
+    while (InterlockedCompareExchange(&db->service_start_lock, TRUE, FALSE))
+    {
+        if (timeout != INFINITE)
+        {
+            timeout -= 10;
+            if (timeout <= 0) return FALSE;
+        }
+        Sleep(10);
+    }
+    return TRUE;
 }
 
 void scmdatabase_unlock_startup(struct scmdatabase *db)
diff --git a/programs/services/services.h b/programs/services/services.h
index fd19ed32f4..5a79c35778 100644
--- a/programs/services/services.h
+++ b/programs/services/services.h
@@ -77,7 +77,7 @@ struct service_entry *scmdatabase_find_service(struct scmdatabase *db, LPCWSTR n
 struct service_entry *scmdatabase_find_service_by_displayname(struct scmdatabase *db, LPCWSTR name);
 DWORD scmdatabase_add_service(struct scmdatabase *db, struct service_entry *entry);
 
-BOOL scmdatabase_lock_startup(struct scmdatabase *db);
+BOOL scmdatabase_lock_startup(struct scmdatabase *db, int timeout);
 void scmdatabase_unlock_startup(struct scmdatabase *db);
 
 void scmdatabase_lock(struct scmdatabase *db);
-- 
2.16.3