cm-async: Cap read/write sizes on streams#13086
Merged
alexcrichton merged 3 commits intobytecodealliance:mainfrom Apr 14, 2026
Merged
cm-async: Cap read/write sizes on streams#13086alexcrichton merged 3 commits intobytecodealliance:mainfrom
alexcrichton merged 3 commits intobytecodealliance:mainfrom
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The spec mandates that stream operations cannot exceed `2**28` elements, but Wasmtime previously did not check for this limit. This meant that the guest could get silently corrupt answers when trying to operate on this many elements. This commit adds a new `ItemCount` newtype wrapper which is intended to be proof of an in-bounds count and then that's plumbed everywhere internally. Closes bytecodealliance#13023
alexcrichton
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wasmtime:api
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Apr 14, 2026
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The spec mandates that stream operations cannot exceed
2**28elements, but Wasmtime previously did not check for this limit. This meant that the guest could get silently corrupt answers when trying to operate on this many elements. This commit adds a newItemCountnewtype wrapper which is intended to be proof of an in-bounds count and then that's plumbed everywhere internally.Closes #13023