Fix race condition in SessionRegistryImpl

Adding/removing sessions from principals wasn't atomic. If one thread
removed the last session from a principal while another thread added a
new one, the addition could be lost.

Fixes gh-3189
This commit is contained in:
Jeffrey Morlan 2019-08-02 16:40:27 -07:00 committed by Rob Winch
parent da62c31fdc
commit a17d66463d
1 changed files with 31 additions and 29 deletions

View File

@ -132,13 +132,18 @@ public class SessionRegistryImpl implements SessionRegistry,
sessionIds.put(sessionId,
new SessionInformation(principal, sessionId, new Date()));
Set<String> sessionsUsedByPrincipal = principals.computeIfAbsent(principal, key -> new CopyOnWriteArraySet<>());
sessionsUsedByPrincipal.add(sessionId);
principals.compute(principal, (key, sessionsUsedByPrincipal) -> {
if (sessionsUsedByPrincipal == null) {
sessionsUsedByPrincipal = new CopyOnWriteArraySet<>();
}
sessionsUsedByPrincipal.add(sessionId);
if (logger.isTraceEnabled()) {
logger.trace("Sessions used by '" + principal + "' : "
+ sessionsUsedByPrincipal);
}
if (logger.isTraceEnabled()) {
logger.trace("Sessions used by '" + principal + "' : "
+ sessionsUsedByPrincipal);
}
return sessionsUsedByPrincipal;
});
}
public void removeSessionInformation(String sessionId) {
@ -157,32 +162,29 @@ public class SessionRegistryImpl implements SessionRegistry,
sessionIds.remove(sessionId);
Set<String> sessionsUsedByPrincipal = principals.get(info.getPrincipal());
if (sessionsUsedByPrincipal == null) {
return;
}
if (logger.isDebugEnabled()) {
logger.debug("Removing session " + sessionId
+ " from principal's set of registered sessions");
}
sessionsUsedByPrincipal.remove(sessionId);
if (sessionsUsedByPrincipal.isEmpty()) {
// No need to keep object in principals Map anymore
principals.computeIfPresent(info.getPrincipal(), (key, sessionsUsedByPrincipal) -> {
if (logger.isDebugEnabled()) {
logger.debug("Removing principal " + info.getPrincipal()
+ " from registry");
logger.debug("Removing session " + sessionId
+ " from principal's set of registered sessions");
}
principals.remove(info.getPrincipal());
}
if (logger.isTraceEnabled()) {
logger.trace("Sessions used by '" + info.getPrincipal() + "' : "
+ sessionsUsedByPrincipal);
}
sessionsUsedByPrincipal.remove(sessionId);
if (sessionsUsedByPrincipal.isEmpty()) {
// No need to keep object in principals Map anymore
if (logger.isDebugEnabled()) {
logger.debug("Removing principal " + info.getPrincipal()
+ " from registry");
}
sessionsUsedByPrincipal = null;
}
if (logger.isTraceEnabled()) {
logger.trace("Sessions used by '" + info.getPrincipal() + "' : "
+ sessionsUsedByPrincipal);
}
return sessionsUsedByPrincipal;
});
}
}