Fix crash in UTF8ToString with resizable ArrayBuffers#27242
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@guybedford this is the kind of thing you warned me about in our last meeting I think.
The fix does seems reasonable. I do wonder if its worth reverting the GROWABLE_ARRAYBUFFERS defaulting to 1 change (#27212) though (in addition to landing this change).
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…rayBuffers getUnsharedTextDecoderView now copies data when the heap buffer is resizable (GROWABLE_ARRAYBUFFERS), and the GROWABLE_ARRAYBUFFERS default is reverted to 0 (as in the upstream 6.0.3 fix), so TextDecoder.decode() no longer rejects the view.
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This makes sense. In the mean time I'd encourage anyone interested in this space to tackle the spec changes to add resizable support to APIs. There's no technical reason not to support resizable buffers short of doing the spec and implementer reach out with regards to ensuring the right security review.
sbc100
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| // This settings does nothing unless ALLOW_MEMORY_GROWTH is set. | ||
| // [link] | ||
| var GROWABLE_ARRAYBUFFERS = 1; | ||
| var GROWABLE_ARRAYBUFFERS = 0; |
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Lets make this a separate PR
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This fixes a crash in
UTF8ToString(and related functions) that occurs when the heap is backed by a resizableArrayBuffer. TheTextDecoder.decode()API throws aTypeErrorwhen passed a view of a resizableArrayBuffer, which previously caused a crash in builds withALLOW_MEMORY_GROWTHandGROWABLE_ARRAYBUFFERSenabled.The
getUnsharedTextDecoderViewfunction insrc/parseTools.mjsis updated to detect when the heap might be resizable and generate code that copies the data using.slice()if the buffer is resizable, ensuringTextDecoderonly receives non-resizable views. A test is added to verify this behavior by emulating the browser's strictTextDecoderimplementation.Closes #27241