[ Reason ]
CVE-2026-103222: integer/pointer overflow

[ Impact ]
Users are vulnerable to being exploited via CVE-2026-103222 with forged
user input.

[ Tests ]
The patch file also includes a regression test for this. It passes on
pkg build.

[ Risks ]
None, just some boundary enforcement. Valid files should not be
affected.

[ Checklist ]
  [x] *all* changes are documented in the d/changelog
  [x] I reviewed all changes and I approve them
  [x] attach debdiff against the package in stable
  [x] the issue is verified as fixed in unstable

[ Changes ]
The untouched upstream patch is included and applies cleanly on the
trixie version.

[ Other info ]
Team upload.