From 7881736c68b43b152e12e8efa2fc67f046046179 Mon Sep 17 00:00:00 2001 From: Simeon Andreev Date: Tue, 24 Nov 2020 16:41:37 +0100 Subject: [PATCH] Bug 569123 - Race condition on AbstractMIControl.fRxCommands This change adds synchronization to iterating over the map AbstractMIControl.fRxCommands during AbstractMIControl.cancelRxCommands(). This prevents potential ConcurrentModificationExceptions when elements are added or removed to the map in parallel during e.g. AbstractMIControl.TxThread.run() loop. The change also removes superfluous synchronization for method AbstractMIControl.cancelRxCommands(). Change-Id: Id7c01b3057e522cce324a002dce54f0fabe02623 Signed-off-by: Simeon Andreev --- .../cdt/dsf/mi/service/command/AbstractMIControl.java | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/command/AbstractMIControl.java b/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/command/AbstractMIControl.java index 4908a50a763..8db4f3b9bf3 100644 --- a/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/command/AbstractMIControl.java +++ b/dsf-gdb/org.eclipse.cdt.dsf.gdb/src/org/eclipse/cdt/dsf/mi/service/command/AbstractMIControl.java @@ -30,6 +30,7 @@ import java.util.Arrays; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; +import java.util.LinkedHashMap; import java.util.LinkedList; import java.util.List; import java.util.Map; @@ -327,14 +328,18 @@ public abstract class AbstractMIControl extends AbstractDsfService implements IM fTxCommands.add(fTerminatorHandle); } - private synchronized void cancelRxCommands() { - for (CommandHandle commandHandle : fRxCommands.values()) { + private void cancelRxCommands() { + Map rxCommandsCopy; + synchronized (fRxCommands) { + rxCommandsCopy = new LinkedHashMap<>(fRxCommands); + fRxCommands.clear(); + } + for (CommandHandle commandHandle : rxCommandsCopy.values()) { if (commandHandle.getRequestMonitor() == null) continue; commandHandle.getRequestMonitor().setStatus(genStatus("Connection is shut down")); //$NON-NLS-1$ commandHandle.getRequestMonitor().done(); } - fRxCommands.clear(); } /**