id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
13111	Out-of-bounds access for asio consuming buffers	ben@…	chris_kohlhoff	"
I have not seen a fix for this in Github for the latest version

https://github.com/boostorg/asio/blob/develop/include/boost/asio/detail/consuming_buffers.hpp

The issue was found by a coverity scan. All calls to buffers_.end() are being flagged as out-of-bounds access, there is potential for memory corruption here. Coverity is flagging these as High Impacting.

Coverity output is below:


{{{

207  // Get a forward-only iterator to the first element.
208  const_iterator begin() const
209  {
   
1. address_of: Taking address with this->buffers_ yields a singleton pointer.
   
CID 336466: Out-of-bounds access (ARRAY_VS_SINGLETON)2. callee_ptr_arith: Passing this->buffers_ to function end which uses it as an array. This might corrupt or misinterpret adjacent memory locations.
210    return const_iterator(at_end_, first_,
211        begin_remainder_, buffers_.end(), max_size_);
212  }
213

…

226  // Consume the specified number of bytes from the buffers.
227  void consume(std::size_t size)
228  {
229    // Remove buffers from the start until the specified size is reached.
   
1. Condition size > 0, taking true branch.
   
2. Condition !this->at_end_, taking true branch.
230    while (size > 0 && !at_end_)
231    {
   
3. Condition boost::asio::buffer_size(this->first_) <= size, taking true branch.
232      if (buffer_size(first_) <= size)
233      {
234        size -= buffer_size(first_);
   
4. address_of: Taking address with this->buffers_ yields a singleton pointer.
   
CID 336464: Out-of-bounds access (ARRAY_VS_SINGLETON)5. callee_ptr_arith: Passing this->buffers_ to function end which uses it as an array. This might corrupt or misinterpret adjacent memory locations.
235        if (begin_remainder_ == buffers_.end())
236          at_end_ = true;
237        else
238          first_ = *begin_remainder_++;
239      }
240      else
241      {
242        first_ = first_ + size;
243        size = 0;
244      }
245    }

…

247    // Remove any more empty buffers at the start.
   
12. Condition !this->at_end_, taking true branch.
   
13. Condition boost::asio::buffer_size(this->first_) == 0, taking true branch.
248    while (!at_end_ && buffer_size(first_) == 0)
249    {
   
14. address_of: Taking address with this->buffers_ yields a singleton pointer.
   
CID 336464: Out-of-bounds access (ARRAY_VS_SINGLETON)15. callee_ptr_arith: Passing this->buffers_ to function end which uses it as an array. This might corrupt or misinterpret adjacent memory locations.
250      if (begin_remainder_ == buffers_.end())
251        at_end_ = true;
252      else
253        first_ = *begin_remainder_++;
254    }
255  }

…

}}}
"	Bugs	new	To Be Determined	asio	Boost 1.66.0	Problem