It was possible to cause a kernel panic in the send code by
initializing an already-initialized mutex, if a record was created
with type DATA, destroyed with a different type (bypassing the
mutex_destroy call) and then re-allocated as a DATA record again.
We tweak the logic to not change the type of a record once it has
been created, avoiding the issue.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes#10374
99b281f1ae