Tracing JIT: Fixed possible stack-buffer-overflow.

Author: dstogov

ext/opcache/jit/zend_jit_vm_helpers.c

@@ -350,7 +350,7 @@ ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL zend_jit_loop_trace_helper(ZEND_OPCODE_HAN
 	trace_buffer[idx].info = _op | (_info); \
 	trace_buffer[idx].ptr = _ptr; \
 	idx++; \
-	if (idx >= ZEND_JIT_TRACE_MAX_LENGTH - 1) { \
+	if (idx >= ZEND_JIT_TRACE_MAX_LENGTH - 2) { \
 		stop = ZEND_JIT_TRACE_STOP_TOO_LONG; \
 		break; \
 	}
@@ -362,7 +362,7 @@ ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL zend_jit_loop_trace_helper(ZEND_OPCODE_HAN
 	trace_buffer[idx].op3_type = _op3_type; \
 	trace_buffer[idx].ptr = _ptr; \
 	idx++; \
-	if (idx >= ZEND_JIT_TRACE_MAX_LENGTH - 1) { \
+	if (idx >= ZEND_JIT_TRACE_MAX_LENGTH - 2) { \
 		stop = ZEND_JIT_TRACE_STOP_TOO_LONG; \
 		break; \
 	}