Fix dangling Instance references in interpreter store#8296
Merged
tlively merged 1 commit intoWebAssembly:mainfrom Feb 11, 2026
Merged
Fix dangling Instance references in interpreter store#8296tlively merged 1 commit intoWebAssembly:mainfrom
tlively merged 1 commit intoWebAssembly:mainfrom
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…rage WasmStore::instances was a std::vector<Instance>, but Frame holds Instance& references. Vector reallocation when adding new instances would silently invalidate all frame references, leading to use-after-free. Switch to std::deque which guarantees that references to existing elements are not invalidated by push_back/emplace_back.
tlively
approved these changes
Feb 11, 2026
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Summary
WasmStore::instanceswas astd::vector<Instance>, butFrameholdsInstance&references. Vector reallocation when adding new instances invalidates all frame references, leading to use-after-free.instancestostd::deque<Instance>, which guarantees that references to existing elements are not invalidated bypush_back/emplace_back.Test plan
InterpreterTest.InstanceReferenceStability— verifies that adding 100 instances does not relocate existing instances or invalidate frame references