The recent changes that added SMB3 encryption support introduced
a possible use after free in the demultiplex thread. When we
process an encrypted packed we obtain a pointer to SMB session
but do not obtain a reference. This can possibly lead to a situation
when this session was freed before we copy a decryption key from
there. Fix this by obtaining a copy of the key rather than a pointer
to the session under a spinlock.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <smfrench@gmail.com>