RDKEMW-15927 : [Xione DE] rbus self-deadlock in XConf privacy mode fetch causing ~188s T2 init delay

[tabbas651]

Reason for change: When UserSettings sets privacy mode to DO_NOT_SHARE during boot,
the rbus SET handler (t2PropertyDataSetHandler) runs synchronously
on the single rbus callback thread — executing deleteAllProfiles()
with pthread_join, disk I/O, and XConf client restart.

The restarted XConf thread calls appendRequestParams() which uses
getParameterValue(PRIVACYMODES_RFC) to fetch privacy mode. This
issues rbus_get() on T2's own bus handle, requiring the same rbus
callback thread that is already blocked processing the SET handler.
This creates a self-deadlock with a 15s rbus timeout per attempt,
compounded by XCONF_RETRY_TIMEOUT (180s), stalling T2 initialization.

Additionally, privacyModeVal global pointer has no mutex protection,
allowing use-after-free and NULL dereference under concurrent
SET/GET operations during stress scenarios.

Cascading effect: While T2 is stalled, external callers (e.g.
WPEFramework SystemServices plugin) invoking t2_event_s() block
15s each on rbus_getUint(Telemetry.OperationalStatus), delaying
the dispatch thread by ~188s and blocking sendNotify() for
EVT_ONSYSTEMPOWERSTATECHANGED. Under concurrent privacy mode
toggling, PROVIDER_NOT_RESPONDING with 26+ messages queued and
dropped, telemetry events fall back to file caching.

Fix:

• rbusInterface.c: Add privacyModeMutex (PTHREAD_MUTEX_INITIALIZER)
  to serialize all reads/writes of privacyModeVal in SET and GET
  handlers, preventing use-after-free and NULL dereference.

• rbusInterface.c: Add privacyModeCallbackWorker() detached thread.
  The SET handler now validates input, updates privacyModeVal under
  mutex, calls setPrivacyMode() for persistence, then dispatches
  heavy callbacks (mprofilesDeleteCallBack, privacyModesDoNotShareCallBack)
  to the worker thread. RBUS handler returns immediately, preventing
  handler thread starvation and cascading 180s timeout loops.

• xconfclient.c: Replace getParameterValue(PRIVACYMODES_RFC) with
  direct getPrivacyMode() call from privacycontrol library. The
  platform implementation (provided via meta layer bbappend) reads
  from a local in-memory cache (PRIVACY_STATE), with fallback to
  Thunder JSON-RPC (local HTTP) and persistent storage — none of
  which use rbus, eliminating the self-deadlock.

• xconf-client/Makefile.am: Add privacycontrol include path and
  build dependency when IS_PRIVACYCONTROL_ENABLED is set. Add else
  branch for libxconfclient_la_CFLAGS to define the variable in all
  automake conditions, fixing autoreconf failure.

• persistence.c: Change rm -f to rm -rf in clearPersistenceFolder()
  non-LIBSYSWRAPPER path. PRIVACYMODE_PATH is a directory, not a
  file; rm -f fails silently leaving stale persistence data.

Test Procedure: Concurrent stress test with multiple privacy mode toggles
(SHARE/DO_NOT_SHARE via curl JSON-RPC), telemetry marker submissions
(telemetry2_0_client), rbuscli reads, and SIGUSR1 signal — all
running simultaneously in background.
Risks: Medium
Signed-off-by: Thamim Razith ThamimRazith_AbbasAli@comcast.com

[Copilot]

Pull request overview

Addresses a startup self-deadlock and knock-on event dispatch delays by removing an rbus re-entrancy path during XConf privacy-mode fetch and by avoiding blocking rbus readiness queries before T2 is initialized.

Changes:

• xconfclient.c: Switch privacy mode query parameter generation to use getPrivacyMode() (privacycontrol) instead of getParameterValue(PRIVACYMODES_RFC) (rbus).
• xconf-client/Makefile.am: Add conditional include path/build dependency for privacycontrol when enabled.
• telemetry_busmessage_sender.c: Fast-fail to caching if the /tmp/.t2ReadyToReceiveEvents marker is absent, avoiding 15s rbus timeouts during early boot.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
source/xconf-client/xconfclient.c	Replaces rbus-based privacy mode fetch with privacycontrol API for XConf request parameterization.
source/xconf-client/Makefile.am	Adds privacycontrol include/dependency under IS_PRIVACYCONTROL_ENABLED.
source/commonlib/telemetry_busmessage_sender.c	Adds marker-file precheck to avoid blocking rbus calls when T2 isn’t ready.

Comments suppressed due to low confidence (1)

source/xconf-client/Makefile.am:49

• When IS_PRIVACYCONTROL_ENABLED is set, this library now calls getPrivacyMode but only adds the privacycontrol library to libxconfclient_la_DEPENDENCIES. DEPENDENCIES controls build order but doesn’t ensure the symbol is linked/propagated to downstream link steps. Add the privacycontrol .la to libxconfclient_la_LIBADD (or appropriate LDADD/LIBADD) so consumers of libxconfclient.la reliably get the required link dependency.

libxconfclient_la_CFLAGS += $(PRIVACYCONTROL_FLAG)
libxconfclient_la_CPPFLAGS += -I${top_srcdir}/source/privacycontrol
libxconfclient_la_DEPENDENCIES += ${top_builddir}/source/privacycontrol/libt2thunder_privacycontrol.la
endif

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 6 comments.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 6 comments.

[Copilot]

t2PropertyDataSetHandler() uses the result of rbusValue_ToString() without checking for NULL. If rbusValue_ToString() fails, the subsequent strcmp() calls will crash. Add a NULL check for data and return RBUS_ERROR_INVALID_INPUT (or similar) when conversion fails.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.