Stream: git-wasmtime

Topic: wasmtime / PR #12870 Fix logic and double-drop UB in `Wri...

Wasmtime GitHub notifications bot (Mar 30 2026 at 08:07):

alexcrichton requested wasmtime-core-reviewers for a review on PR #12870.

Wasmtime GitHub notifications bot (Mar 30 2026 at 08:07):

alexcrichton requested dicej for a review on PR #12870.

Wasmtime GitHub notifications bot (Mar 30 2026 at 08:07):

alexcrichton opened PR #12870 from alexcrichton:fix-write-buffer to bytecodealliance:main:

For component-model-async this fixes logic and undefined behavior issues in the implementation of the WriteBuffer trait for various types. Notably all types didn't respect the unsafe contract of the WriteBuffer::take method by limiting the number of results to what was requested. This flawed detail, when coupled with other implementation details, led to both incorrect results and UB in the case that VecBuffer<T> was used where T had a Drop implementation. This is not a security issue because component-model-async is not yet Tier 1 and thus is exempt from the security issue process, but this is nonetheless something needed to be fixed.

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Wasmtime GitHub notifications bot (Mar 30 2026 at 08:07):

alexcrichton requested wasmtime-default-reviewers for a review on PR #12870.

Wasmtime GitHub notifications bot (Mar 30 2026 at 10:05):

github-actions[bot] added the label wasmtime:api on PR #12870.

Wasmtime GitHub notifications bot (Mar 30 2026 at 14:03):

dicej submitted PR review.

Wasmtime GitHub notifications bot (Mar 30 2026 at 14:08):

alexcrichton added PR #12870 Fix logic and double-drop UB in WriteBuffer impls to the merge queue.

Wasmtime GitHub notifications bot (Mar 30 2026 at 16:41):

alexcrichton merged PR #12870.

Wasmtime GitHub notifications bot (Mar 30 2026 at 16:41):

alexcrichton removed PR #12870 Fix logic and double-drop UB in WriteBuffer impls from the merge queue.

Last updated: Apr 12 2026 at 23:10 UTC