CVE-2026-98459Bluetooth: ISO: balance the parent hold in hci_bind_bis()

Official description

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().

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/ff28e6c67143c76ef50c3eac01f2fad411705f71
• https://git.kernel.org/stable/c/03a91cdf6862fb351a74f035ad21e70112438552
• https://git.kernel.org/stable/c/4e49206d9574a4c109480198e73aea34ad0ed7f6
• https://git.kernel.org/stable/c/bbcd723ee7a84bc868142fd57717af88e54e555a
• https://git.kernel.org/stable/c/4c94557dd02569efa6c1072a0439addaef9a5224