lxd/instance/drivers: Handle websocket closing

When the VM disconnects due to a stop/reboot, the error is a `connection reset by peer` instead of a EOF, so this helps handle this error.

Signed-off-by: hamistao <[email protected]>

lxd/instance/drivers/driver_qemu_cmd.go

@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"io"
 	"strconv"
+	"strings"
+	"syscall"
 
 	"golang.org/x/sys/unix"
 
@@ -80,7 +82,9 @@ func (c *qemuCmd) Wait() (int, error) {
 		// Error of type EOF indicates the session ended unexpectedly,
 		// so we inform the client of the disconnection with a more
 		// descriptive message.
-		if errors.Is(err, io.EOF) {
+		// VMs can also disconnect due to a reboot/stop, so we handle
+		// these disconnections errors similarly.
+		if errors.Is(err, io.EOF) || strings.Contains(err.Error(), syscall.ECONNRESET.Error()) {
 			return exitStatus, ErrExecDisconnected
 		}