russell@unturf.com
9934133dcf
Add 88 new defect entries to HIGH and MEDIUM tables:
HIGH: mysql-0001/0002, mariadb-0001, redis-0001/0002, valkey-0001/0002, openvpn-0001,
vlc-0001, prometheus-0001, otel-collector-0001, cockroachdb-0001..0004,
tidb-0001..0008, kubernetes-0001/0002, go-0001, kotlin-0002, scala-0001,
allegro5-0001, sdl2-0001, grafana-0001, clickhouse-0001, duckdb-0001,
mongodb-0001, envoy-0001, istio-0001, cilium-0001, linkerd2-0001,
linux-0001/0002/0003, tor-0002/0003, curl-0001, julia-0001, lua-0001,
perl5-0001, nats-0001, spring-0003/0004, tomcat-0001, onos-0002, odl-0002
MEDIUM: helm-0001, mariadb-0002, openssl-0001/0002, memcached-0001,
cassandra-0001..0004, flink-0001, storm-0001/0002, zookeeper-0001..0003,
pip-0001, gradle-0001, nginx-0001, haproxy-0001, caddy-0001, varnish-0001,
ffmpeg-0001, gstreamer-0001, raylib-0001, love2d-0001, php-0001/0002,
r-source-0001, cpython-0002, ruby-0001, rabbitmq-0003/0004, activemq-0001,
ovs-0001, onos-0003, odl-0002, jetty-0001
PDF: 976K
2.2 KiB
tomcat-0001: ReplicationValve cross-context session dedup — ArrayList.contains() O(n²)
Target: Apache Tomcat
File: java/org/apache/catalina/ha/tcp/ReplicationValve.java
CWE: CWE-407 — Inefficient Algorithmic Complexity
Severity: MEDIUM
Status: PATCHED
Description
ReplicationValve.registerReplicationSession() accumulates cross-context
DeltaSession objects in a ThreadLocal<ArrayList<DeltaSession>>. For each
incoming session it checks membership with sessions.contains(session) before
adding, where sessions is ArrayList<DeltaSession>.
In Portlet-style deployments the comment in the code explicitly notes that
"the Portlet API can include a lot of fragments from same or different
applications with session changes." Each call to registerReplicationSession()
does a full linear scan of the growing list — O(n) per call — producing
O(n²) total work when n sessions are registered for a single request.
// ReplicationValve.java line 80, 265-275
protected final ThreadLocal<ArrayList<DeltaSession>> crossContextSessions = new ThreadLocal<>();
public void registerReplicationSession(DeltaSession session) {
List<DeltaSession> sessions = crossContextSessions.get();
if (sessions != null) {
if (!sessions.contains(session)) { // O(n) scan per call → O(n²) total
sessions.add(session);
}
}
}
Fix
Replace ArrayList<DeltaSession> with LinkedHashSet<DeltaSession> in the
ThreadLocal initialiser. Set.add() is idempotent so the contains() guard
is unnecessary and can be removed entirely.
protected final ThreadLocal<LinkedHashSet<DeltaSession>> crossContextSessions = new ThreadLocal<>();
public void registerReplicationSession(DeltaSession session) {
LinkedHashSet<DeltaSession> sessions = crossContextSessions.get();
if (sessions != null) {
sessions.add(session); // O(1) — Set deduplicates automatically
}
}
Callers that iterate sessions (lines 394, 422) are unaffected — LinkedHashSet
is Iterable and preserves insertion order.
Patch
defects/tomcat/patch/tomcat-0001.patch
Unit Test
defects/tomcat/unit/TomcatReplicationValveTest.java