x/net/netutil: LimitListener Accept() does not unblock when Close() is called with connection limit reached.

[akmistry]

What version of Go are you using (go version)?

go version go1.9.2 linux/amd64

Does this issue reproduce with the latest release?

Untested, but issue is not with the runtime.

What operating system and processor architecture are you using (go env)?

GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/amistry/go-src"
GORACE=""
GOROOT="/home/amistry/go"
GOTOOLDIR="/home/amistry/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build151791535=/tmp/go-build -gno-record-gcc-switches"
CXX="g++"
CGO_ENABLED="1"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"

What did you do?

Use netutil.LimitListener and accept the maximum number of connections. Without closing any connections, close the listener. According to the net.Listener interface, any active Accept() calls should unblock and error. LimitListener does not do this.

https://play.golang.org/p/6PL6suf4CUP

What did you expect to see?

Accept() unblocks with an error.

What did you see instead?

Accept() stays blocked.

Bug and solution are trivial. I'll send a CL soon.

[gopherbot]

Change https://golang.org/cl/101535 mentions this issue: netutil: Unblock LimitListener.Accept on Close.