Wt

It is possible that SessionProcess::readHandler() is called when the socket has been deleted. Likely this occurs when read() and stop() are called near simultaneously.
stop() will have closed the socket and set it to a nullptr, but read() had already been scheduled.

At the moment that the socket closes, readHandler() is called, with a nullptr object, causing a segfault.
Ensuring that all operations on the socket are cancelled when the socket closes, ought to resolve this issue.