SECURITY UPDATE: out-of-bounds stack write when a bz2 decompressor or
BZ2File handle is reused after a decompression error
debian/patches/CVE-2026-9669.patch: record the bzlib error code on
BZ2DecompObject and refuse further decompress() calls with
ValueError in Modules/bz2module.c, so that crafted input can no
longer make BZ2_bzDecompress() resume from an invalid internal
state; also make the error sticky for the C BZ2File read paths,
which re-entered the errored stream in the same way, and add
regression tests for both