The host inspects a package to read manifest.yaml and requirements.txt before the
SDK extracts it. Inspection normalized entry names with only
replace('\\','/').strip('/'), so it accepted names its own extractor rejects
(absolute paths, '..' components, drive letters) and it silently kept the first
member when two normalized to the same path.
There was no traversal write, because the SDK's _extract_verified_zip validates
every member before writing and the host only reads members by ZipInfo. The bug
is the divergence: a package could pass inspection and then fail to install, and
the two rule sets could drift further as either side changes.
Inspection now applies the same rule set as the SDK, via
_normalize_archive_entry_name: reject empty/NUL names, absolute paths, any '..'
component and drive letters; reject a duplicate after normalization. '.' and
empty segments are still collapsed, so './manifest.yaml' and 'components//x.py'
keep working.
Tests: 13 cases covering each rejection, the duplicate, traversal taking
precedence over the duplicate check, and two positive cases (nested/unicode
layout, cosmetic separators).
Co-authored-by: multica-agent <[email protected]>
