fix: bound debian ParseControlFile to a single control stanza#38044
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Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
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#38055) Backport #38044 by @metsw24-max **Packages-index stanza injection via Debian control file** A `.deb` whose `control` file appends extra paragraphs after a blank line was still accepted, and `ParseControlFile` stored the whole multi-stanza blob in `p.Control`. That blob is re-emitted verbatim into the generated `Packages` index, so the embedded blank line splits it into separate stanzas and an uploader can smuggle a package entry with an attacker-chosen `Filename` into the shared index. A binary control file only holds one stanza, so parsing now stops at the blank line that terminates it; well-formed packages are unaffected and the new subtest covers the trailing-stanza case. Signed-off-by: wxiaoguang <wxiaoguang@gmail.com> Co-authored-by: metsw24-max <metsw24@gmail.com> Co-authored-by: wxiaoguang <wxiaoguang@gmail.com> Co-authored-by: bircni <bircni@icloud.com>
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Packages-index stanza injection via Debian control file
A
.debwhosecontrolfile appends extra paragraphs after a blank line was still accepted, andParseControlFilestored the whole multi-stanza blob inp.Control. That blob is re-emitted verbatim into the generatedPackagesindex, so the embedded blank line splits it into separate stanzas and an uploader can smuggle a package entry with an attacker-chosenFilenameinto the shared index. A binary control file only holds one stanza, so parsing now stops at the blank line that terminates it; well-formed packages are unaffected and the new subtest covers the trailing-stanza case.