Avoid recursive use of signal blocking macros in ZendAccelerator.c

Author: alexdowad

Zend/zend.c

@@ -78,8 +78,15 @@ ZEND_API void zend_debug_mask_signals()
 }
 ZEND_API void zend_debug_unmask_signals()
 {
-	if (--_signals_masked)
-	  zend_error_noreturn(E_ERROR, "Cannot nest ZEND_SIGNAL_BLOCK_INTERRUPTIONS; it is not re-entrant");
+	if (--_signals_masked) {
+	  zend_error_noreturn(E_ERROR, "Cannot nest HANDLE_BLOCK_INTERRUPTIONS; it is not re-entrant");
+	}
+}
+ZEND_API void zend_debug_ensure_signals_masked()
+{
+	if (!_signals_masked) {
+		zend_error_noreturn(E_ERROR, "Must block signals using HANDLE_BLOCK_INTERRUPTIONS");
+	}
 }
 # endif
 #endif

Zend/zend_signal.h

@@ -26,9 +26,11 @@ extern sigset_t mask_all_signals;
 # if ZEND_DEBUG
 ZEND_API void zend_debug_mask_signals();
 ZEND_API void zend_debug_unmask_signals();
+ZEND_API void zend_debug_ensure_signals_masked();
 # else
 #  define zend_debug_mask_signals()   do {} while (0)
 #  define zend_debug_unmask_signals() do {} while (0)
+#  define zend_debug_ensure_signals_masked() do {} while (0)
 # endif
 
 # define ZEND_SIGNAL_BLOCK_INTERRUPTIONS() \
@@ -55,6 +57,7 @@ ZEND_API void zend_debug_unmask_signals();
 
 # define ZEND_SIGNAL_BLOCK_INTERRUPTIONS()   do {} while(0)
 # define ZEND_SIGNAL_UNBLOCK_INTERRUPTIONS() do {} while(0)
+# define zend_debug_ensure_signals_masked()  do {} while(0)
 
 #endif /* HAVE_SIGPROCMASK */
 #endif /* ZEND_SIGNAL_H */

ext/opcache/ZendAccelerator.c

@@ -2131,7 +2131,9 @@ zend_op_array *persistent_compile_file(zend_file_handle *file_handle, int type)
 				if (ZSMMG(memory_exhausted)) {
 					zend_accel_restart_reason reason =
 						zend_accel_hash_is_full(&ZCSG(hash)) ? ACCEL_RESTART_HASH : ACCEL_RESTART_OOM;
+					HANDLE_BLOCK_INTERRUPTIONS();
 					zend_accel_schedule_restart_if_necessary(reason);
+					HANDLE_UNBLOCK_INTERRUPTIONS();
 				}
 			}
 			zend_shared_alloc_unlock();
@@ -2156,7 +2158,9 @@ zend_op_array *persistent_compile_file(zend_file_handle *file_handle, int type)
 				if (ZSMMG(memory_exhausted)) {
 					zend_accel_restart_reason reason =
 						zend_accel_hash_is_full(&ZCSG(hash)) ? ACCEL_RESTART_HASH : ACCEL_RESTART_OOM;
+					HANDLE_BLOCK_INTERRUPTIONS();
 					zend_accel_schedule_restart_if_necessary(reason);
+					HANDLE_UNBLOCK_INTERRUPTIONS();
 				}
 			}
 			zend_shared_alloc_unlock();
@@ -3227,7 +3231,9 @@ void zend_accel_schedule_restart(zend_accel_restart_reason reason)
 	zend_accel_error(ACCEL_LOG_DEBUG, "Restart Scheduled! Reason: %s",
 			zend_accel_restart_reason_text[reason]);
 
-	HANDLE_BLOCK_INTERRUPTIONS();
+	/* This function must be called with signals blocked */
+	zend_debug_ensure_signals_masked();
+
 	SHM_UNPROTECT();
 	ZCSG(restart_pending) = 1;
 	ZCSG(restart_reason) = reason;
@@ -3240,7 +3246,6 @@ void zend_accel_schedule_restart(zend_accel_restart_reason reason)
 		ZCSG(force_restart_time) = 0;
 	}
 	SHM_PROTECT();
-	HANDLE_UNBLOCK_INTERRUPTIONS();
 }
 
 /* this is needed because on WIN32 lock is not decreased unless ZCG(counted) is set */