fusefs: fix a kernel panic regarding SCM_RIGHTSHEADmain

If the last copy of an open file resides within the socket buffer of a
unix-domain socket, then VOP_CLOSE will be called with no thread
information.  Fix fusefs to handle that case, and add a regression test.

Also add a test case for writes to a file that lies within a sockbuf.
Along with close, a write from the writeback cache is the only other
operation I can think of that might apply to a file residing in a
sockbuf.

PR:		289686
Reported by:	iron.udjin@gmail.com
MFC after:	1 week
Sponsored by:	ConnectWise
Reviewed by:	glebius, markj
Differential Revision: https://reviews.freebsd.org/D52625

0 files changed, 0 insertions, 0 deletions