net/sched: cls_fw: fix NULL dereference of "old" filters before change()

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CVE-2026-53080

CVE-2026-53080 affects the Linux kernel net/sched cls_fw. Description in connected advisories shows that a NULL dereference could occur for old-style filters during shared-block publication, leading to a crash/warn during packet classification. The fix skips “old-style” classification on shared b...

DEBIAN-CVE-2006-5778

ftpd in linux-ftpd 0.17, and possibly other versions, performs a chdir before setting the UID, which allows local users to bypass intended access restrictions by redirecting their home directory to a restricted directory...