If dnslisten_readcb gets a read callback it needs to verify that the
outer socket wasn't closed in the meantime, and issue a CANCELED callback
if it was.
(cherry picked from commit 3ab3d90de0)
If dnslisten_readcb gets a read callback it needs to verify that the
outer socket wasn't closed in the meantime, and issue a CANCELED callback
if it was.
(cherry picked from commit 3ab3d90de0)