Fix parsing of traceql queries longer than 1024 chars (#3571)

* fix really long static vals

Signed-off-by: Joe Elliott <number101010@gmail.com>

* protect against long attr names as well

Signed-off-by: Joe Elliott <number101010@gmail.com>

---------

Signed-off-by: Joe Elliott <number101010@gmail.com>

pkg/traceql/lexer.go

@@ -270,14 +270,24 @@ func parseQuotedAtrribute(s *scanner.Scanner) (string, error) {
 }
 
 func tryScopeAttribute(l *scanner.Scanner, currentScope int) (int, bool) {
+	const longestScope = 9 // "resource." is the longest scope
+
 	// copy the scanner to avoid advancing if it's not a scope.
 	s := *l
 	str := ""
 	for s.Peek() != scanner.EOF {
-		if s.Peek() == '.' {
+		r := s.Peek()
+		if r == '.' { // we've found a scope attribute
 			str += string(s.Next())
 			break
 		}
+		if !isAttributeRune(r) { // we can't have a scope with invalid characters, so just bail
+			break
+		}
+		if len(str) > longestScope { // we can't have a scope longer than the longest scope, so just bail
+			break
+		}
+
 		str += string(s.Next())
 	}
 	tok := tokens[str]

pkg/traceql/parse_test.go

@@ -1,6 +1,7 @@
 package traceql
 
 import (
+	"fmt"
 	"strings"
 	"testing"
 	"time"
@@ -1166,3 +1167,27 @@ func TestHints(t *testing.T) {
 		})
 	}
 }
+
+func TestReallyLongQuery(t *testing.T) {
+	for i := 1000; i < 1050; i++ {
+		longVal := strings.Repeat("a", i)
+
+		// static value
+		query := fmt.Sprintf("{ .a = `%s` }", longVal)
+		expected := newBinaryOperation(OpEqual, NewAttribute("a"), NewStaticString(longVal))
+
+		actual, err := Parse(query)
+
+		require.NoError(t, err, "i=%d", i)
+		require.Equal(t, newRootExpr(newPipeline(newSpansetFilter(expected))), actual, "i=%d", i)
+
+		// attr name
+		query = fmt.Sprintf("{ .%s = `foo` }", longVal)
+		expected = newBinaryOperation(OpEqual, NewAttribute(longVal), NewStaticString("foo"))
+
+		actual, err = Parse(query)
+
+		require.NoError(t, err, "i=%d", i)
+		require.Equal(t, newRootExpr(newPipeline(newSpansetFilter(expected))), actual, "i=%d", i)
+	}
+}