eds: use-after-free in LEDS callback on subsequent EDS updates#43667
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botengyao merged 2 commits intoenvoyproxy:mainfrom Mar 2, 2026
Merged
eds: use-after-free in LEDS callback on subsequent EDS updates#43667botengyao merged 2 commits intoenvoyproxy:mainfrom
botengyao merged 2 commits intoenvoyproxy:mainfrom
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The LEDS subscription callback lambda captured `used_load_assignment` by value as a raw pointer to the object owned by the `cluster_load_assignment_` unique_ptr. When a subsequent EDS update reassigned `cluster_load_assignment_`, the old object was destroyed but existing LEDS subscriptions (not recreated for unchanged configs) still held the dangling pointer. When the LEDS subscription later fired its callback (e.g. onConfigUpdateFailed), dereferencing this pointer caused a segfault. Stack trace: #0: [0x77b9d6de8330] envoyproxy#1: Envoy::Upstream::EdsClusterImpl::BatchUpdateHelper::batchUpdate() envoyproxy#2: Envoy::Upstream::PrioritySetImpl::batchHostUpdate() envoyproxy#3: std::__1::__function::__func<>::operator()() envoyproxy#4: Envoy::Upstream::LedsSubscription::onConfigUpdateFailed() envoyproxy#5: Envoy::Config::GrpcSubscriptionImpl::onConfigUpdateFailed() envoyproxy#6: event_process_active_single_queue envoyproxy#7: event_base_loop envoyproxy#8: Envoy::Server::InstanceBase::run() Fix by capturing `this` and accessing `cluster_load_assignment_` directly, which always reflects the current valid assignment. Signed-off-by: William Dauchy <william.dauchy@datadoghq.com>
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botengyao
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Mar 2, 2026
bmjask
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Mar 14, 2026
…proxy#43667) Commit Message: The LEDS subscription callback lambda captured `used_load_assignment` by value as a raw pointer to the object owned by the `cluster_load_assignment_` unique_ptr. When a subsequent EDS update reassigned `cluster_load_assignment_`, the old object was destroyed but existing LEDS subscriptions (not recreated for unchanged configs) still held the dangling pointer. When the LEDS subscription later fired its callback (e.g. onConfigUpdateFailed), dereferencing this pointer caused a segfault. Stack trace: ``` #0: [0x77b9d6de8330] envoyproxy#1: Envoy::Upstream::EdsClusterImpl::BatchUpdateHelper::batchUpdate() envoyproxy#2: Envoy::Upstream::PrioritySetImpl::batchHostUpdate() envoyproxy#3: std::__1::__function::__func<>::operator()() envoyproxy#4: Envoy::Upstream::LedsSubscription::onConfigUpdateFailed() envoyproxy#5: Envoy::Config::GrpcSubscriptionImpl::onConfigUpdateFailed() envoyproxy#6: event_process_active_single_queue envoyproxy#7: event_base_loop envoyproxy#8: Envoy::Server::InstanceBase::run() ``` Fix by capturing `this` and accessing `cluster_load_assignment_` directly, which always reflects the current valid assignment. Additional Description: Risk Level: Testing: Docs Changes: Release Notes: Platform Specific Features: [Optional Runtime guard:] [Optional Fixes #Issue] [Optional Fixes commit #PR or SHA] [Optional Deprecated:] [Optional [API Considerations](https://github.com/envoyproxy/envoy/blob/main/api/review_checklist.md):] Signed-off-by: William Dauchy <william.dauchy@datadoghq.com> Signed-off-by: bjmask <11672696+bjmask@users.noreply.github.com>
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Mar 17, 2026
…proxy#43667) Commit Message: The LEDS subscription callback lambda captured `used_load_assignment` by value as a raw pointer to the object owned by the `cluster_load_assignment_` unique_ptr. When a subsequent EDS update reassigned `cluster_load_assignment_`, the old object was destroyed but existing LEDS subscriptions (not recreated for unchanged configs) still held the dangling pointer. When the LEDS subscription later fired its callback (e.g. onConfigUpdateFailed), dereferencing this pointer caused a segfault. Stack trace: ``` #0: [0x77b9d6de8330] envoyproxy#1: Envoy::Upstream::EdsClusterImpl::BatchUpdateHelper::batchUpdate() envoyproxy#2: Envoy::Upstream::PrioritySetImpl::batchHostUpdate() envoyproxy#3: std::__1::__function::__func<>::operator()() envoyproxy#4: Envoy::Upstream::LedsSubscription::onConfigUpdateFailed() envoyproxy#5: Envoy::Config::GrpcSubscriptionImpl::onConfigUpdateFailed() envoyproxy#6: event_process_active_single_queue envoyproxy#7: event_base_loop envoyproxy#8: Envoy::Server::InstanceBase::run() ``` Fix by capturing `this` and accessing `cluster_load_assignment_` directly, which always reflects the current valid assignment. Additional Description: Risk Level: Testing: Docs Changes: Release Notes: Platform Specific Features: [Optional Runtime guard:] [Optional Fixes #Issue] [Optional Fixes commit #PR or SHA] [Optional Deprecated:] [Optional [API Considerations](https://github.com/envoyproxy/envoy/blob/main/api/review_checklist.md):] Signed-off-by: William Dauchy <william.dauchy@datadoghq.com>
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Commit Message:
The LEDS subscription callback lambda captured
used_load_assignmentby value as a raw pointer to the object owned by thecluster_load_assignment_unique_ptr. When a subsequent EDS update reassignedcluster_load_assignment_, the old object was destroyed but existing LEDS subscriptions (not recreated for unchanged configs) still held the dangling pointer. When the LEDS subscription later fired its callback (e.g. onConfigUpdateFailed), dereferencing this pointer caused a segfault.Stack trace:
Fix by capturing
thisand accessingcluster_load_assignment_directly, which always reflects the current valid assignment.Additional Description:
Risk Level:
Testing:
Docs Changes:
Release Notes:
Platform Specific Features:
[Optional Runtime guard:]
[Optional Fixes #Issue]
[Optional Fixes commit #PR or SHA]
[Optional Deprecated:]
[Optional API Considerations:]