Merge pull request #131230 from cockroachdb/blathers/backport-release…

…-24.2.3-rc-131209

release-24.2.3-rc: sqlliveness: detect and handle invalid SessionIDs

pkg/sql/catalog/lease/lease_internal_test.go

@@ -1709,8 +1709,8 @@ func TestLeaseCountDetailSessionBased(t *testing.T) {
 		version := 1
 		region := enum.One
 		_, err := executor.Exec(ctx, "add-rows-for-test", nil,
-			fmt.Sprintf("INSERT INTO system.lease VALUES (%d, %d, %s, '%s', '\\x%x')",
-				descID, version, nodeID, session.ID(), region))
+			fmt.Sprintf("INSERT INTO system.lease VALUES (%d, %d, %s, '\\x%x', '\\x%x')",
+				descID, version, nodeID, session.ID().UnsafeBytes(), region))
 		if err != nil {
 			return err
 		}

pkg/sql/logictest/testdata/logic_test/sqlliveness

@@ -0,0 +1,36 @@
+# Validate that invalid sessionID's are always
+# considered dead.
+subtest invalid_sessions
+
+# Legacy non-RBR format
+query B
+select crdb_internal.sql_liveness_is_alive(x'1f915e98f96145a5baa9f3a42c378eb6');
+----
+false
+
+# Wrong length
+query B
+select crdb_internal.sql_liveness_is_alive(x'deadbeef');
+----
+false
+
+subtest end
+
+
+subtest valid_sessions
+
+# Sanity: All sessions are alive in sqlliveness.
+query I
+SELECT count(*) FROM system.sqlliveness WHERE crdb_internal.sql_liveness_is_alive(session_id) = false;
+----
+0
+
+query B
+SELECT count(*) > 0 FROM system.sqlliveness WHERE crdb_internal.sql_liveness_is_alive(session_id) = true;
+----
+true
+
+subtest end
+
+
+

pkg/sql/sqlliveness/slstorage/key_encoder.go

@@ -24,6 +24,7 @@ import (
 type keyCodec interface {
 	encode(sid sqlliveness.SessionID) (roachpb.Key, string, error)
 	decode(key roachpb.Key) (sqlliveness.SessionID, error)
+	validate(session sqlliveness.SessionID) error
 
 	// indexPrefix returns the prefix for an encoded key. encode() will return
 	// something with the prefix and decode will expect a key with this prefix.
@@ -37,6 +38,10 @@ type rbrEncoder struct {
 	rbrIndex roachpb.Key
 }
 
+func (e *rbrEncoder) validate(session sqlliveness.SessionID) error {
+	return ValidateSessionID(session)
+}
+
 func (e *rbrEncoder) encode(session sqlliveness.SessionID) (roachpb.Key, string, error) {
 	region, _, err := SafeDecodeSessionID(session)
 	if err != nil {

pkg/sql/sqlliveness/slstorage/sessionid.go

@@ -67,18 +67,8 @@ func MakeSessionID(region []byte, id uuid.UUID) (sqlliveness.SessionID, error) {
 // not be mutated.
 func UnsafeDecodeSessionID(session sqlliveness.SessionID) (region, id []byte, err error) {
 	b := session.UnsafeBytes()
-	if len(b) == legacyLen {
-		return nil, nil, errors.Newf("unexpected legacy SessionID format")
-	}
-	if len(b) < minimumNonLegacyLen {
-		// The smallest valid v1 session id is a [version, 1, single_byte_region, uuid...],
-		// which is three bytes larger than a uuid.
-		return nil, nil, errors.New("session id is too short")
-	}
-
-	// Decode the version.
-	if b[0] != sessionIDVersion {
-		return nil, nil, errors.Newf("invalid session id version: %d", b[0])
+	if err = ValidateSessionID(sqlliveness.SessionID(b)); err != nil {
+		return nil, nil, err
 	}
 	regionLen := int(b[1])
 	rest := b[2:]
@@ -91,24 +81,30 @@ func UnsafeDecodeSessionID(session sqlliveness.SessionID) (region, id []byte, er
 	return rest[:regionLen], rest[regionLen:], nil
 }
 
-// SafeDecodeSessionID decodes the region and id from the SessionID.
-func SafeDecodeSessionID(session sqlliveness.SessionID) (region, id string, err error) {
+// ValidateSessionID validates that the SessionID has the correct format.
+func ValidateSessionID(session sqlliveness.SessionID) error {
 	if len(session) == legacyLen {
-		return "", "", errors.Newf("unexpected legacy SessionID format")
+		return errors.Newf("unexpected legacy SessionID format")
 	}
 	if len(session) < minimumNonLegacyLen {
 		// The smallest valid v1 session id is a [version, 1, single_byte_region, uuid...],
 		// which is three bytes larger than a uuid.
-		return "", "", errors.New("session id is too short")
+		return errors.New("session id is too short")
 	}
-
 	// Decode the version.
 	if session[0] != sessionIDVersion {
-		return "", "", errors.Newf("invalid session id version: %d", session[0])
+		return errors.Newf("invalid session id version: %d", session[0])
+	}
+	return nil
+}
+
+// SafeDecodeSessionID decodes the region and id from the SessionID.
+func SafeDecodeSessionID(session sqlliveness.SessionID) (region, id string, err error) {
+	if err = ValidateSessionID(session); err != nil {
+		return "", "", err
 	}
 	regionLen := int(session[1])
 	rest := session[2:]
-
 	// Decode and validate the length of the region.
 	if len(rest) != regionLen+uuid.Size {
 		return "", "", errors.Newf("session id with length %d is the wrong size to include a region with length %d", len(session), regionLen)

pkg/sql/sqlliveness/slstorage/slstorage.go

@@ -200,7 +200,15 @@ const (
 func (s *Storage) isAlive(
 	ctx context.Context, sid sqlliveness.SessionID, syncOrAsync readType,
 ) (alive bool, _ error) {
-
+	// Confirm the session ID has the correct format, and if it
+	// doesn't then we can consider it as dead without any extra
+	// work.
+	if err := s.keyCodec.validate(sid); err != nil {
+		// This SessionID may be invalid because of the wrong format
+		// so consider it as dead.
+		//nolint:returnerrcheck
+		return false, nil
+	}
 	// If wait is false, alive is set and future is unset.
 	// If wait is true, alive is unset and future is set.
 	alive, wait, future, err := func() (bool, bool, singleflight.Future, error) {
@@ -318,6 +326,9 @@ func (s *Storage) deleteOrFetchSession(
 	ctx = multitenant.WithTenantCostControlExemption(ctx)
 	livenessProber := regionliveness.NewLivenessProber(s.db, s.codec, nil, s.settings)
 	k, regionPhysicalRep, err := s.keyCodec.encode(sid)
+	if err != nil {
+		return false, hlc.Timestamp{}, err
+	}
 	if err := s.txn(ctx, func(ctx context.Context, txn *kv.Txn) error {
 		// Reset captured variable in case of retry.
 		deleted, expiration, prevExpiration = false, hlc.Timestamp{}, hlc.Timestamp{}