[Boost-bugs] [Boost C++ Libraries] #2910: asio & ssl - leaking io_handler when user-provided handler throws

Subject: [Boost-bugs] [Boost C++ Libraries] #2910: asio & ssl - leaking io_handler when user-provided handler throws
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2009-04-03 21:21:04

#2910: asio & ssl - leaking io_handler when user-provided handler throws
-----------------------------------------------------------------------------------------+
 Reporter:  Paul Groke <pgroke_at_[hidden]>                                                   |       Owner:  chris_kohlhoff
     Type:  Bugs                                                                         |      Status:  new           
Milestone:  Boost 1.39.0                                                                 |   Component:  asio          
  Version:  Boost 1.38.0                                                                 |    Severity:  Problem       
 Keywords:  asio ssl handler io_handler leak throw throws delete openssl_stream_service  |  
-----------------------------------------------------------------------------------------+
 The function
 boost::asio::ssl::detail::openssl_stream_service::io_handler<>::handler_impl
 isn't exception safe, and therefor leaks, if the invoked user-provided
 handler throws. Since many people bind shared_ptr<>s into their handlers,
 this will also keep alive their session objects. I'd consider this a major
 issue.
 (Please feel free to raise the priority to show-stopper if you think
 that's appropriate :-)

 The current implementation (1.38.0 & trunk at the moment of filing this
 ticket) looks like this:
 {{{
     void handler_impl(const boost::system::error_code& error, size_t size)
     {
       handler_(error, size);
       delete this;
     }
 }}}

 Fix should be obvious:
 {{{
 #include <memory> // for std::auto_ptr<>

 // ...

     void handler_impl(const boost::system::error_code& error, size_t size)
     {
       std::auto_ptr<io_handler> guard(this); // or something similar
       handler_(error, size);
     }
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/2910>
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