CVE-2026-98459

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: ISO: balance the parent hold in hci bind bis()

hci conn link() takes a lifetime reference to its parent with hci conn get(), but only takes an operational hold on the child. hci conn unlink() later balances both a hold and a reference on the parent.

The SCO and CIS paths pass a parent acquired from a connect helper, so it already has a hold. For an additional BIS, hci bind bis() obtains the parent from hci conn hash lookup big(), which returns a bare pointer. Unlinking the child then drops the parent's existing hold and can schedule it for disconnection while its socket is still using it.

Take a hold on the parent before linking it and drop that hold if linking fails. A successful link transfers the hold to hci conn unlink().