Free native resources on three rare decoder error paths - #2587
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- Image::loadGIFFromBuffer: delete[] the decode buffer before returning CAIRO_STATUS_READ_ERROR when neither a local nor a global color map exists. The full width*height*4 buffer was previously dropped. - Image::assignDataAsMime: capture the cairo_surface_set_mime_data return status; on non-success, reverse the AdjustExternalMemory(env, len) and free both mime_data (a copy of the JPEG buffer) and mime_closure, which cairo never takes ownership of in the failure case. - create_transparent_pattern: destroy mask_context and mask_surface before returning NULL when cairo_create reports an error status (cairo OOM). All three are real ownership bugs but sit behind error/OOM gates that aren't reachable in normal operation, so there's no measurable RSS slope to attach. Bundled because each is a one- or two-line fix in the same family. Fixes Automattic#2586
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Trim the fork to only the memory leaks reproduced with before/after RSS: - JPEG EXIF rotation (rotate90/rotate270) leak (Automattic#2574, merged upstream) - RsvgHandle / partial cairo surface leak on SVG decode error paths (Automattic#2585) Revert everything else back to v3.2.3 after testing: image.src-on-error (Automattic#2580, no measurable effect), libjpeg longjmp data/src free (Automattic#2581, not reproducible on libjpeg-turbo), cairo_pattern_t refcount (Automattic#2582), CanvasPattern source-retention UAF guard (Automattic#2583), rare decoder error-path frees (Automattic#2587), and the node-addon-api 8 / NAPI_EXPERIMENTAL experiment. Built on node-addon-api 7. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Closing: these are real ownership fixes by inspection, but (as the PR notes) they sit behind error/OOM gates with no measurable RSS slope — not reproducible. Scoping to fixes reproduced with before/after measurements. |
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Fixes #2586.
Three small ownership bugs on rare error paths in image decoders and pattern construction. None are reachable in normal operation, but each is a real leak when its gate fires.
Changes
Image::loadGIFFromBuffer:delete[]the decode buffer before returningCAIRO_STATUS_READ_ERRORwhen neither a local nor a global color map exists. Per-occurrence leak is the fullwidth * height * 4buffer.Image::assignDataAsMime: capture thecairo_surface_set_mime_datareturn status; on non-success, reverse theNapi::MemoryManagement::AdjustExternalMemory(env, len)andfreebothmime_data(a copy of the JPEG buffer) andmime_closure. Cairo doesn't take ownership in the failure case and never callsclearMimeData, so both allocations otherwise live forever.create_transparent_pattern: destroymask_contextandmask_surfacebefore returningNULLwhencairo_createreports an error status. Only reachable on cairo OOM.Verification
These are behind error/OOM gates that aren't reachable from JS without poking at internals, so no RSS reproduction is attached. The fixes are visible by inspection and total +12 / -1 lines.