[Boost-bugs] [Boost C++ Libraries] #4772: binary_buffer_iprimitive fails on vector access when reading in zero length item at end of buffer_

Subject: [Boost-bugs] [Boost C++ Libraries] #4772: binary_buffer_iprimitive fails on vector access when reading in zero length item at end of buffer_
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-10-22 19:37:12

#4772: binary_buffer_iprimitive fails on vector access when reading in zero length
item at end of buffer_
---------------------------------------------------------------+------------
 Reporter:  Jeff Jackowski <jeff.jackowski@…>                  |       Owner:  dgregor
     Type:  Bugs                                               |      Status:  new    
Milestone:  To Be Determined                                   |   Component:  mpi    
  Version:  Boost 1.43.0                                       |    Severity:  Problem
 Keywords:                                                     |  
---------------------------------------------------------------+------------
 When binary_buffer_iprimitive's position == buffer_.size() and
 binary_buffer_iprimitive::load_impl is called with l = 0, the bracket
 operator on buffer_ will attempt an out of bounds access. The assertion in
 load_impl suggests the author was aware these conditions are normal since
 the assertion evaluates to true. However, the parameters for the call to
 std::memcpy cannot be evaluated because an assertion within buffer_ fails.
 Changing load_impl to look like this fixes the problem:

 void load_impl(void * p, int l)
 {
   assert(position+l<=static_cast<int>(buffer_.size()));
   if (l)
   {
           std::memcpy(p,&buffer_[position],l);
           position += l;
   }
 }

 It looks like the bug should also exist in Boost's trunk, but I cannot get
 the software I'm working on to build with Boost 1.44 and newer, but that
 is another issue.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4772>
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