upstream: fix net, imp doc

upstream/doh.go

@@ -220,7 +220,7 @@ func (p *dnsOverHTTPS) exchangeHTTPS(client *http.Client, req *dns.Msg) (resp *d
 	}
 
 	logBegin(p.addrRedacted, n, req)
-	defer func() { logFinish(p.addrRedacted, networkTCP, err) }()
+	defer func() { logFinish(p.addrRedacted, n, err) }()
 
 	return p.exchangeHTTPSClient(client, req)
 }

upstream/upstream.go

@@ -11,6 +11,7 @@ import (
 	"net"
 	"net/netip"
 	"net/url"
+	"os"
 	"strconv"
 	"strings"
 	"sync/atomic"
@@ -305,14 +306,21 @@ func logFinish(addr string, n network, err error) {
 }
 
 // isTimeout returns true if err is a timeout error.
+//
+// TODO(e.burkov):  Move to golibs.
 func isTimeout(err error) (ok bool) {
-	if errors.Is(err, context.DeadlineExceeded) {
+	var netErr net.Error
+	switch {
+	case
+		errors.Is(err, context.Canceled),
+		errors.Is(err, context.DeadlineExceeded),
+		errors.Is(err, os.ErrDeadlineExceeded):
 		return true
+	case errors.As(err, &netErr):
+		return netErr.Timeout()
+	default:
+		return false
 	}
-
-	var netErr net.Error
-
-	return errors.As(err, &netErr) && netErr.Timeout()
 }
 
 // DialerInitializer returns the handler that it creates.  All the subsequent