Re: Stream device problem with redirection in @mismatch

[Michael Johnson <michaelj@jlab.org>]

Hi there,

We are seeing a very similar problem at Jefferson Lab. Buffer overflows as soon as I process a device record.

I am using Stream over Asyn with CR-only terminators, configured ala:

# String terminator settings at ASYN level (? - MJ)
asynOctetSetInputEos("PGUNFDIV",0,"\r")
asynOctetSetOutputEos("PGUNFDIV",0,"\r")

#DEBUGGING
asynSetTraceMask("PGUNFDIV",-1,0x9)
asynSetTraceIOMask("PGUNFDIV",-1,0x2)

In Stream, I do not set any terminators (redundant?). 

I am getting these errors after applying the patch. Any thoughts?

Cexp>2015/04/10 12:25:29.570 104-Com-8sm write -1 , bufflen = 1, buffaddr = 8c4edc
\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\004\000\000\000@\000\000\000\004\000\000\000\004\314\225\000\000\000\000\000\000\000\000\000\000
2015/04/10 12:25:29.910 104-Com-8sm write 0
Program heap: free of bad pointer 8C4EDC -- range 832928 - 1F6C0000
2015/04/10 12:25:30.210 104-Com-8sm write -1 , bufflen = 1, buffaddr = 9894c4
\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\004\000\000\000@\000\000\000\004\000\000\000\004\314\225\000\000\000\000\000\000\000\000\000\000
2015/04/10 12:25:30.570 104-Com-8sm write 0
Program heap: free of bad pointer 98assertion "(uread(BSP_UART_COM1, LSR) & THRE) != 0" failed: file "../../../../../../../../rtems-4.9.2/c/src/lib/libbsp/i386/pc386/../../i386/shared/comm/uart.c", line 585, function: BSP_uart_termios_write_com1

Here is the path I applied (after changing "print" to "printf" to get it to compile):

StreamEpics.cc
916,918c916,918
<         StreamBuffer fullname;
<         fullname.printf("%s.%s", name(), fieldname);
<         if (dbNameToAddr(fullname(), &dbaddr) != OK)
---
>         char fullname[PVNAME_SZ + 1];
>         sprintf(fullname, "%s.%s", name(), fieldname);
>         if (dbNameToAddr(fullname, &dbaddr) != OK)
921,923c921,923
<             fullname.clear().printf("%s.VAL", fieldname);
<             if (dbNameToAddr(fullname(), &dbaddr) != OK) return false;
<         }
---
>             sprintf(fullname, "%s.VAL", fieldname);
>             if (dbNameToAddr(fullname, &dbaddr) != OK) return false;
>         }

With Context:

[205] michaelj@devl01 > diff -c StreamEpics.cc StreamEpics.cc.orig

*** StreamEpics.cc    2015-04-09 14:57:09.264306145 -0400
--- StreamEpics.cc.orig    2015-04-09 14:13:40.706615881 -0400
***************
*** 913,926 ****
      else
      {
          // FIELD in this record or VAL in other record
!         StreamBuffer fullname;
!         fullname.printf("%s.%s", name(), fieldname);
!         if (dbNameToAddr(fullname(), &dbaddr) != OK)
          {
              // VAL in other record
!             fullname.clear().printf("%s.VAL", fieldname);
!             if (dbNameToAddr(fullname(), &dbaddr) != OK) return false;
!         }
      }
      address.append(&dbaddr, sizeof(dbaddr));
      return true;
--- 913,926 ----
      else
      {
          // FIELD in this record or VAL in other record
!         char fullname[PVNAME_SZ + 1];
!         sprintf(fullname, "%s.%s", name(), fieldname);
!         if (dbNameToAddr(fullname, &dbaddr) != OK)
          {
              // VAL in other record
!             sprintf(fullname, "%s.VAL", fieldname);
!             if (dbNameToAddr(fullname, &dbaddr) != OK) return false;
!         }
      }
      address.append(&dbaddr, sizeof(dbaddr));
      return true;

THANKS for reading! - Mike J

On Wed, Apr 8, 2015 at 5:37 AM, Dirk Zimoch <dirk.zimoch@psi.ch> wrote:

On 08.04.2015 11:20, Dirk Zimoch wrote:

 >
/usr/local/epics/support/stream/StreamDevice-2-6/lib/linux-x86_64/libstream.so(_ZN6Stream15getFieldAddressEPKcR12StreamBuffer+0xcd)[0x7f9c3d4bd34d]


I found the bug in getFieldAddress:

         // FIELD in this record or VAL in other record
         char fullname[PVNAME_SZ + 1];
         sprintf(fullname, "%s.%s", name(), fieldname);
         if (dbNameToAddr(fullname, &dbaddr) != OK)
         {
             // VAL in other record
             sprintf(fullname, "%s.VAL", fieldname);
             if (dbNameToAddr(fullname, &dbaddr) != OK) return false;
         }

The first sprintf prints
$(device):StatEnable.$(device):StatEnableInterlock which is way too
long. My fault. I will send a patch soon....

Dirk

Try this:
        // FIELD in this record or VAL in other record
        StreamBuffer fullname;
        fullname.print("%s.%s", name(), fieldname);
        if (dbNameToAddr(fullname(), &dbaddr) != OK)
        {
            // VAL in other record
            fullname.clear().print("%s.VAL", fieldname);
            if (dbNameToAddr(fullname(), &dbaddr) != OK) return false;
        }

(in src/StreamEpics.cc function getFieldAddress)

Dirk