core/logger: sanitize escape chars in console logs (#11402)

core/logger/internal/colortest/prettyconsole_test.go

@@ -61,6 +61,12 @@ func TestPrettyConsole_Write(t *testing.T) {
 			"2018-04-12T12:55:28Z \x1b[91m[FATAL] \x1b[0mtop level                                          \x1b[34m\x1b[0m                        \n",
 			false,
 		},
+		{
+			"control",
+			`{"ts":1523537728, "level":"fatal", "msg":"\u0008\t\n\r\u000b\u000c\ufffd\ufffd", "hash":"nuances"}`,
+			"2018-04-12T12:55:28Z \x1b[91m[FATAL] \x1b[0m\\b\t\n\r\\v\\f��                                        \x1b[34m\x1b[0m                        \n",
+			false,
+		},
 		{"broken", `{"broken":}`, `{}`, true},
 	}
 

core/logger/prettyconsole.go

@@ -6,8 +6,10 @@ import (
 	"net/url"
 	"os"
 	"sort"
+	"strconv"
 	"strings"
 	"time"
+	"unicode"
 
 	"github.com/fatih/color"
 	"github.com/tidwall/gjson"
@@ -72,7 +74,7 @@ func generateHeadline(js gjson.Result) string {
 		tsStr,
 		" ",
 		coloredLevel(js.Get("level")),
-		fmt.Sprintf("%-50s", js.Get("msg")),
+		fmt.Sprintf("%-50s", sanitized(js.Get("msg").String())),
 		" ",
 		fmt.Sprintf("%-32s", blue(js.Get("caller"))),
 	}
@@ -105,7 +107,7 @@ func generateDetails(js gjson.Result) string {
 	var details strings.Builder
 
 	for _, v := range keys {
-		details.WriteString(fmt.Sprintf("%s=%v ", green(v), data[v]))
+		details.WriteString(fmt.Sprintf("%s=%v ", green(sanitized(v)), sanitized(data[v].String())))
 	}
 
 	return details.String()
@@ -129,3 +131,26 @@ func prettyConsoleSink(s zap.Sink) func(*url.URL) (zap.Sink, error) {
 		return PrettyConsole{s}, nil
 	}
 }
+
+type sanitized string
+
+// String replaces control characters with Go escape sequences, except for newlines and tabs.
+// See strconv.QuoteRune.
+func (s sanitized) String() string {
+	var out string
+	for _, r := range s {
+		switch r {
+		case '\n', '\r', '\t':
+			// allowed
+		default:
+			// escape others
+			if unicode.IsControl(r) {
+				q := strconv.QuoteRune(r)
+				out += q[1 : len(q)-1] // trim quotes
+				continue
+			}
+		}
+		out += string(r)
+	}
+	return out
+}

docs/CHANGELOG.md

@@ -54,6 +54,7 @@ LatestReportDeadline = "5s" # Default
 ### Changed
 
 - `L2Suggested` mode is now called `SuggestedPrice`
+- Console logs will now escape (non-whitespace) control characters
 
 ### Removed