[BugFix] Capture query context when use its mem_tracker out of its li…

…fetime (backport #49123) (#49202)

Signed-off-by: satanson <[email protected]>

be/src/runtime/runtime_filter_worker.cpp

@@ -3,6 +3,7 @@
 #include "runtime/runtime_filter_worker.h"
 
 #include <random>
+#include <utility>
 
 #include "exec/pipeline/query_context.h"
 #include "exprs/vectorized/runtime_filter_bank.h"
@@ -23,15 +24,23 @@
 
 namespace starrocks {
 
-static inline std::shared_ptr<MemTracker> get_mem_tracker(const PUniqueId& query_id, bool is_pipeline) {
+// Using a query-level mem_tracker beyond QueryContext's lifetime may access already destructed parent mem_tracker.
+// mem_trackers has a hierarchy: process->query_pool->resource_group->query, so when resource_group is dropped or
+// altered, resource_group-level mem_tracker would be destructed, such a dangling query-level mem_tracker would cause
+// BE's crash when it accesses its parent mem_tracker(i.e. resource_group-level mem_tracker). so we need capture
+// query context to prevent it from being destructed, and when a dropping resource_group is used by outstanding query
+// contexts, it would be delayed to be dropped until all its outstanding query contexts are destructed.
+static inline std::pair<pipeline::QueryContextPtr, std::shared_ptr<MemTracker>> get_mem_tracker(
+        const PUniqueId& query_id, bool is_pipeline) {
     if (is_pipeline) {
         TUniqueId tquery_id;
         tquery_id.lo = query_id.lo();
         tquery_id.hi = query_id.hi();
         auto query_ctx = ExecEnv::GetInstance()->query_context_mgr()->get(tquery_id);
-        return query_ctx == nullptr ? nullptr : query_ctx->mem_tracker();
+        auto mem_tracker = query_ctx == nullptr ? nullptr : query_ctx->mem_tracker();
+        return std::make_pair(query_ctx, mem_tracker);
     } else {
-        return nullptr;
+        return std::make_pair(nullptr, nullptr);
     }
 }
 
@@ -199,7 +208,7 @@ Status RuntimeFilterMerger::init(const TRuntimeFilterParams& params) {
 }
 
 void RuntimeFilterMerger::merge_runtime_filter(PTransmitRuntimeFilterParams& params) {
-    auto mem_tracker = get_mem_tracker(params.query_id(), params.is_pipeline());
+    auto [query_ctx, mem_tracker] = get_mem_tracker(params.query_id(), params.is_pipeline());
     SCOPED_THREAD_LOCAL_MEM_TRACKER_SETTER(mem_tracker.get());
 
     DCHECK(params.is_partial());
@@ -628,7 +637,7 @@ static inline Status receive_total_runtime_filter_pipeline(
 }
 
 void RuntimeFilterWorker::_receive_total_runtime_filter(PTransmitRuntimeFilterParams& request) {
-    auto mem_tracker = get_mem_tracker(request.query_id(), request.is_pipeline());
+    auto [query_ctx, mem_tracker] = get_mem_tracker(request.query_id(), request.is_pipeline());
     SCOPED_THREAD_LOCAL_MEM_TRACKER_SETTER(mem_tracker.get());
     // deserialize once, and all fragment instance shared that runtime filter.
     vectorized::JoinRuntimeFilter* rf = nullptr;
@@ -701,7 +710,7 @@ void RuntimeFilterWorker::_receive_total_runtime_filter(PTransmitRuntimeFilterPa
 
 void RuntimeFilterWorker::_process_send_broadcast_runtime_filter_event(
         PTransmitRuntimeFilterParams&& params, std::vector<TRuntimeFilterDestination>&& destinations, int timeout_ms) {
-    auto mem_tracker = get_mem_tracker(params.query_id(), params.is_pipeline());
+    auto [query_ctx, mem_tracker] = get_mem_tracker(params.query_id(), params.is_pipeline());
     SCOPED_THREAD_LOCAL_MEM_TRACKER_SETTER(mem_tracker.get());
 
     std::random_device rd;