--- embedaddon/smartmontools/dev_areca.cpp	2013/07/22 01:17:35	1.1.1.1
+++ embedaddon/smartmontools/dev_areca.cpp	2013/10/14 07:54:03	1.1.1.2
@@ -21,7 +21,7 @@
 #include "dev_interface.h"
 #include "dev_areca.h"
 
-const char * dev_areca_cpp_cvsid = "$Id: dev_areca.cpp,v 1.1.1.1 2013/07/22 01:17:35 misho Exp $"
+const char * dev_areca_cpp_cvsid = "$Id: dev_areca.cpp,v 1.1.1.2 2013/10/14 07:54:03 misho Exp $"
   DEV_ARECA_H_CVSID;
 
 #include "atacmds.h"
@@ -356,7 +356,8 @@ int generic_areca_device::arcmsr_get_dev_type()
   int ctlr_type = -1;
   int encnum = get_encnum();
   int disknum = get_disknum();
-  unsigned char areca_packet[] = {0x5E, 0x01, 0x61, 0x03, 0x00, 0x22, disknum - 1, encnum - 1, 0x00};
+  unsigned char areca_packet[] = {0x5E, 0x01, 0x61, 0x03, 0x00, 0x22,
+    (unsigned char)(disknum - 1), (unsigned char)(encnum - 1), 0x00};
 
   memset(return_buff, 0, sizeof(return_buff));
   expected = arcmsr_ui_handler(areca_packet, sizeof(areca_packet), return_buff);
@@ -612,10 +613,11 @@ bool generic_areca_device::arcmsr_scsi_pass_through(st
 
   // ----- BEGIN TO SEND TO ARECA DRIVER ------
   expected = arcmsr_ui_handler(areca_packet, areca_packet_len, return_buff);
-  if ( expected < 0 )
-  {
-    return set_err(EIO);
-  }
+
+  if (expected < 0)
+    return set_err(EIO, "arcmsr_scsi_pass_through: I/O error");
+  if (expected < 15) // 7 bytes if port is empty
+    return set_err(EIO, "arcmsr_scsi_pass_through: missing data (%d bytes, expected %d)", expected, 15);
 
   int scsi_status = return_buff[5];
   int in_data_len = return_buff[11] | return_buff[12] << 8 | return_buff[13] << 16 | return_buff[14] << 24;