From f3d95607036b8a502c65aa7b3e8145227274dbbc Mon Sep 17 00:00:00 2001 From: Eyal Soha Date: Wed, 5 Feb 2020 17:56:00 -0800 Subject: recv() on a closed TCP socket returns ENOTCONN From RFC 793 s3.9 p58 Event Processing: If RECEIVE Call arrives in CLOSED state and the user has access to such a connection, the return should be "error: connection does not exist" Fixes #1598 PiperOrigin-RevId: 293494287 --- pkg/sentry/socket/netstack/netstack.go | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'pkg/sentry/socket/netstack/netstack.go') diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go index 049d04bf2..ed2fbcceb 100644 --- a/pkg/sentry/socket/netstack/netstack.go +++ b/pkg/sentry/socket/netstack/netstack.go @@ -2229,11 +2229,16 @@ func (s *SocketOperations) coalescingRead(ctx context.Context, dst usermem.IOSeq var copied int // Copy as many views as possible into the user-provided buffer. - for dst.NumBytes() != 0 { + for { + // Always do at least one fetchReadView, even if the number of bytes to + // read is 0. err = s.fetchReadView() if err != nil { break } + if dst.NumBytes() == 0 { + break + } var n int var e error -- cgit v1.2.3