fix(telephony): prevent SIM subscriptions sync when altering SIM state

To reproduce this: 1. Ensure the device is using the legacy radio interface layer (RIL) to control SIM cards 2. Toggle the same SIM card multiple times in a row 3. Observe the SIM card forcefully returning to its original state due to the synchronization with its schedules Deep-dive explanation: When performing the SIM subscription state mutation for the same SIM card multiple times in a row (#1-12 & #13-24), this will sooner trigger in parallel the global carrier config changed event listener (#25), which in turn will run the SIM subscriptions sync process. In this case, the SIM subscriptions sync process may short-circuit and terminate fast, or it may force override user's preference applied a moment ago through the scheduler (#41). This is because the last{Activated/Deactivated}Time fields used to determine whether to keep the user's preference within the allowed period or not was reset during the SIM subscriptions sync process, since the SIM subscription can be temporarily unavailable (#38) during state transition. The fix: This patch fix introduces an atomic flag to block the synchronization of the internal state of all SIM subscriptions during SIM subscription state mutations. Currently, this issue affects heavily only devices using legacy RIL, but we'll use the flag on the newer RIL too, since there's a call to the database that may take longer to complete in some circumstances. #1 D 7SIM.SimListViewModel handleOnSimEnabledStateChanged(simEntryId=1,enabled=false). #2 D 7SIM.TelephonyController setSimState(slotIndex=1,enabled=false,keepDisabledAcrossBoots=true) : In sync block. #3 V 7SIM.SubscriptionsImplLegacy persistSubscription(sub=Subscription { id=1 slotIndex=1 simState=DISABLED iconTint=-4056997 name=Vodafone lastActivatedTime=-999999999-01-01T00:00 lastDeactivatedTime=2024-08-23T14:51 keepDisabledAcrossBoots=true }). #4 D 7SIM.SubscriptionsImplLegacy persistSubscriptionState(subId=1,state=DISABLED). #5 V 7SIM.SubscriptionsImplLegacy addOnSimStatusChangedListener(). #6 V 7SIM.SubscriptionsImplLegacy registerCarrierConfigChangedReceiver(). #7 V 7SIM.SubscriptionsImplLegacy onReceive() : intent=Intent { act=android.telephony.action.SIM_CARD_STATE_CHANGED flg=0x5000010 (has extras) } #8 V 7SIM.SubscriptionsImplLegacy dispatchOnSimStatusChanged(slotIndex=1,state=1). #9 V 7SIM.TelephonyController onSimStatusChanged(slotIndex=1,state=1). #10 V 7SIM.SubscriptionsImplLegacy removeOnSimStatusChangedListener(). #11 V 7SIM.SubscriptionsImplLegacy unregisterCarrierConfigChangedReceiver(). #12 D 7SIM.TelephonyController handleOnSetSimPowerStateForSlotFinished(resCode=1) : requestMetadata=Bundle[{last_activated_time=-999999999-01-01T00:00, last_deactivated_time=2024-08-23T14:51, subscription=Subscription { id=1 slotIndex=1 simState=DISABLED iconTint=-4056997 name=Vodafone lastActivatedTime=-999999999-01-01T00:00 lastDeactivatedTime=2024-08-23T14:51 keepDisabledAcrossBoots=true }, keep_disabled_across_boots=true}], requestFailed=false,shouldNotifyAllListeners=false #13 D 7SIM.SimListViewModel handleOnSimEnabledStateChanged(simEntryId=1,enabled=true). #14 D 7SIM.TelephonyController setSimState(slotIndex=1,enabled=true,keepDisabledAcrossBoots=false) : In sync block. #15 V 7SIM.SubscriptionsImplLegacy persistSubscription(sub=Subscription { id=1 slotIndex=1 simState=ENABLED iconTint=-4056997 name=Vodafone lastActivatedTime=2024-08-23T14:51 lastDeactivatedTime=-999999999-01-01T00:00 keepDisabledAcrossBoots=false }). #16 D 7SIM.SubscriptionsImplLegacy persistSubscriptionState(subId=1,state=ENABLED). #17 V 7SIM.SubscriptionsImplLegacy addOnSimStatusChangedListener(). #18 V 7SIM.SubscriptionsImplLegacy registerCarrierConfigChangedReceiver(). #19 V 7SIM.SubscriptionsImplLegacy onReceive() : intent=Intent { act=android.telephony.action.SIM_CARD_STATE_CHANGED flg=0x5000010 (has extras) } #20 V 7SIM.SubscriptionsImplLegacy dispatchOnSimStatusChanged(slotIndex=1,state=11). #21 V 7SIM.TelephonyController onSimStatusChanged(slotIndex=1,state=11). #22 V 7SIM.SubscriptionsImplLegacy removeOnSimStatusChangedListener(). #23 V 7SIM.SubscriptionsImplLegacy unregisterCarrierConfigChangedReceiver(). #24 D 7SIM.TelephonyController handleOnSetSimPowerStateForSlotFinished(resCode=11) : requestMetadata=Bundle[{last_activated_time=2024-08-23T14:51, last_deactivated_time=-999999999-01-01T00:00, subscription=Subscription { id=1 slotIndex=1 simState=ENABLED iconTint=-4056997 name=Vodafone lastActivatedTime=2024-08-23T14:51 lastDeactivatedTime=-999999999-01-01T00:00 keepDisabledAcrossBoots=false }, keep_disabled_across_boots=false}], requestFailed=false,shouldNotifyAllListeners=true #25 D 7SIM.DirectBootAwareBroadcastReceiver onReceive() : intent=Intent { act=android.telephony.action.CARRIER_CONFIG_CHANGED flg=0x15000010 cmp=com.github.iusmac.sevensim/.DirectBootAwareBroadcastReceiver (has extras) } #26 D 7SIM.ForegroundService onCreate(). #27 D 7SIM.ForegroundService onStartCommand(intent=Intent { act=ACTION_SUBSCRIPTIONS_CHANGED cmp=com.github.iusmac.sevensim/.ForegroundService (has extras) },flags=0,startId=1). #28 D 7SIM.ForegroundService Worker.execute(taskId=1) Add : mQueueSize=0. #29 D 7SIM.ForegroundService onStartCommand(intent=Intent { act=ACTION_SYNC_SUBSCRIPTION_ENABLED_STATE cmp=com.github.iusmac.sevensim/.ForegroundService (has extras) },flags=0,startId=2). #30 D 7SIM.ForegroundService Worker.execute(taskId=1) Start : mQueueSize=1. #31 D 7SIM.ForegroundService Worker.execute(taskId=2) Add : mQueueSize=1. #32 D 7SIM.ForegroundService onStartCommand(intent=Intent { act=ACTION_UPDATE_NEXT_WEEKLY_REPEAT_SCHEDULE_PROCESSING_ITER cmp=com.github.iusmac.sevensim/.ForegroundService (has extras) },flags=0,startId=3). #33 D 7SIM.ForegroundService Worker.execute(taskId=3) Add : mQueueSize=2. #34 D 7SIM.SubscriptionsImplLegacy syncSubscriptions(dateTime=2024-08-23T14:51:08.280) : Subscription { id=2 slotIndex=0 simState=ENABLED iconTint=-13408298 name=Vodafone (work) lastActivatedTime=-999999999-01-01T00:00 lastDeactivatedTime=-999999999-01-01T00:00 keepDisabledAcrossBoots=false },currentSubState=ENABLED,expectedSubState=UNKNOWN,existsInUsableList=false. #35 D 7SIM.SubscriptionsImplLegacy persistSubscriptionState(subId=2,state=ENABLED). #36 D 7SIM.SubscriptionsImplLegacy syncSubscriptions(dateTime=2024-08-23T14:51:08.280) : Subscription { id=1 slotIndex=-1 simState=UNKNOWN iconTint=-16777216 name= lastActivatedTime=2024-08-23T14:51 lastDeactivatedTime=-999999999-01-01T00:00 keepDisabledAcrossBoots=false }. #37 V 7SIM.SubscriptionsImplLegacy persistSubscription(sub=Subscription { id=1 slotIndex=-1 simState=UNKNOWN iconTint=-16777216 name= lastActivatedTime=-999999999-01-01T00:00 lastDeactivatedTime=-999999999-01-01T00:00 keepDisabledAcrossBoots=false }). #38 D 7SIM.SubscriptionsImplLegacy persistSubscriptionState(subId=1,state=UNKNOWN). #39 D 7SIM.ForegroundService Worker.execute(taskId=1) Finish : mQueueSize=2. #40 D 7SIM.ForegroundService Worker.execute(taskId=2) Start : mQueueSize=2. #41 D 7SIM.SubscriptionScheduler syncSubscriptionEnabledState(subId=2,compareTime=2024-08-23T14:51:08.280,overrideUserPreference=false) : Subscription { id=2 slotIndex=0 simState=ENABLED iconTint=-13408298 name=Vodafone (work) lastActivatedTime=-999999999-01-01T00:00 lastDeactivatedTime=-999999999-01-01T00:00 keepDisabledAcrossBoots=false },nearestEnableTime=Optional.empty,nearestDisableTime=Optional[2024-08-19T08:00],expectedEnabled=false,isInCall=false. #42 D 7SIM.TelephonyController setSimState(slotIndex=0,enabled=false,keepDisabledAcrossBoots=false) : In sync block. Signed-off-by: iusmac <[email protected]> # Please enter the commit message for your changes. Lines starting # with '#' will be kept; you may remove them yourself if you want to. # An empty message aborts the commit. # # Date: Fri Aug 23 16:04:50 2024 +0200 # # interactive rebase in progress; onto 7db7f56 # Last command done (1 command done): # edit 42ea1228 fix(telephony): prevent SIM subscriptions sync when altering SIM state # Next command to do (1 remaining command): # exec GIT_AUTHOR_NAME='iusmac' GIT_AUTHOR_EMAIL='[email protected]' GIT_AUTHOR_DATE='Fri Aug 23 16:04:50 2024 +0200' GIT_COMMITTER_NAME='iusmac' GIT_COMMITTER_EMAIL='[email protected]' GIT_COMMITTER_DATE='Fri Aug 23 16:04:50 2024 +0200' git commit --quiet --amend --reset-author --no-edit # You are currently editing a commit while rebasing branch '14.0-dev' on '7db7f568'. # # Changes to be committed: # modified: src/com/github/iusmac/sevensim/telephony/SubscriptionController.java # modified: src/com/github/iusmac/sevensim/telephony/Subscriptions.java # modified: src/com/github/iusmac/sevensim/telephony/TelephonyController.java #
iusmac · Aug 23, 2024 · 2eba7cd · 2eba7cd
1 parent 7db7f56
commit 2eba7cd
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diff --git a/src/com/github/iusmac/sevensim/telephony/SubscriptionController.java b/src/com/github/iusmac/sevensim/telephony/SubscriptionController.java
@@ -71,6 +71,9 @@ public void setUiccApplicationsEnabled(final int subId, final boolean enabled) {
             return;
         }
 
+        // Ensure SIM subscription syncing cannot start in parallel during this operation
+        mSubscriptions.mBlockSubscriptionsSyncFlag.set(true);
+
         sub.setSimState(TelephonyUtils.simStateInt(enabled));
         sub.setLastActivatedTime(enabled ? LocalDateTime.now(ZoneId.systemDefault()) :
                 LocalDateTime.MIN);
@@ -79,5 +82,7 @@ public void setUiccApplicationsEnabled(final int subId, final boolean enabled) {
         mSubscriptions.persistSubscription(sub);
 
         mSubManager.setUiccApplicationsEnabled(subId, enabled);
+
+        mSubscriptions.mBlockSubscriptionsSyncFlag.set(false);
     }
 }
diff --git a/src/com/github/iusmac/sevensim/telephony/Subscriptions.java b/src/com/github/iusmac/sevensim/telephony/Subscriptions.java
@@ -99,6 +99,12 @@ public void onReceive(final Context context, final Intent intent) {
      */
     private final AtomicBoolean mCarrierConfigChangedReceiverRegistered = new AtomicBoolean();
 
+    /**
+     * Atomic flag indicating whether the synchronization of the internal state of all SIM
+     * subscriptions is blocked or not. Use this to ensure atomic SIM subscription state mutations.
+     */
+    final AtomicBoolean mBlockSubscriptionsSyncFlag = new AtomicBoolean();
+
     private final Context mContext;
     protected final Logger mLogger;
     protected final SubscriptionManager mSubscriptionManager;
@@ -295,6 +301,11 @@ public void removeOnSubscriptionsChangedListener(
      */
     @WorkerThread
     public void syncSubscriptions(final LocalDateTime dateTime) {
+        if (mBlockSubscriptionsSyncFlag.get()) {
+            mLogger.w("syncSubscriptions(dateTime=%s) : Operation has been disallowed.", dateTime);
+            return;
+        }
+
         final List<String> removedSubIds = new ArrayList<>(getPersistedUsableSubIds());
         final List<String> usableSubIds = new ArrayList<>();
 

diff --git a/src/com/github/iusmac/sevensim/telephony/TelephonyController.java b/src/com/github/iusmac/sevensim/telephony/TelephonyController.java
@@ -135,6 +135,9 @@ public void setSimState(final int slotIndex, final boolean enabled,
                 return;
             }
 
+            // Ensure SIM subscription syncing cannot start in parallel during this operation
+            mSubscriptions.mBlockSubscriptionsSyncFlag.set(true);
+
             // Keep track of SIM state whenever it's mutated. This will be persisted in a volatile
             // memory, so that we can further restore all relevant data. This because when powering
             // down the SIM is the same as removing it, which means the SIM will completely
@@ -226,6 +229,8 @@ public void setSimState(final int slotIndex, final boolean enabled,
                 }
                 handleOnSetSimPowerStateForSlotFinished(resCode);
             }
+
+            mSubscriptions.mBlockSubscriptionsSyncFlag.set(false);
         }
     }