K 10
svn:author
V 3
kib
K 8
svn:date
V 27
2020-05-14T17:54:08.638662Z
K 7
svn:log
V 755
Fix spurious ENOTCONN from closed unix domain socket other' side.

Sometimes, when doing read(2) over unix domain socket, for which the
other side socket was closed, read(2) returns -1/ENOTCONN instead of
EOF AKA zero-size read. This is because soreceive_generic() does not
lock socket when testing the so_state SS_ISCONNECTED|SS_ISCONNECTING
flags. It could end up that we do not observe so->so_rcv.sb_state bit
SBS_CANTRCVMORE, and then miss SS_ flags.

Change the test to check that the socket was never connected before
returning ENOTCONN, by adding all state bits for connected.

Reported and tested by:	pho
In collaboration with:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D24819

END