Merge release-20200127.0-84-gf3d9560 (automated)

1 files changed, 6 insertions, 1 deletions

diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go
index 049d04bf2..ed2fbcceb 100755
--- 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