CLI may only copy data for null terminated values

[Cliff Gray]

The CLI interface, ExeCliInterface::executeImmediate and executeImmmediateExec take a Boolean, nullTerminate, that is intended to control whether a trailing null is added after returned data. However, for some queries, if the Boolean is not set to true, the data is not copied.

The suspicious code is in ExeCliInterface::executeImmediate.

  if ((outputBuf) &&
      (outputBufLen))
    {
      *outputBufLen = 0;
      if (retcode != 100)
 {
   if (nullTerminate)
     {
       char * ptr;
       Lng32 len;
       getPtrAndLen(1, ptr, len);

       str_cpy_all(outputBuf, ptr, len);

       outputBuf[len] = 0;
       *outputBufLen = len;
     }
   else
     *outputBufLen = outputDatalen_;
 }
    }

Perhaps the get and copy code should be outside the if (nullTerminate) block.

Queries that result in data not being copied unless nullTerminate is set to true include:

SELECT MAX(columnName) FROM table [WHERE condition];

For called to executeImmediate where the value is not a null-terminated string, passing true for the parameter nullTerminate results in a null/zero being placed in the byte of a variable on the stack near the passed outputBuf. A workaround is to declare dummy variables around the passed outputBuf.

[Sandhya Sundaresan (sandhya-sundaresan)]

The CLI code that was doing the memory overwrite was fixed.
Corresponding kludges were removed in the security code that worked around the original problem and were fixed in Change-Id: If7538eee38178c2345fe418172c6196b25a20b33