In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: hold conn in hci_connect_big_sync() callback There is theoretical UAF if the conn is freed while the hci_sync task is running. Hold refcount to avoid that. Handle NULL hcon, return 0 + do nothing to match the previous behavior.
https://git.kernel.org/stable/c/ff5625d27415ace5667bf87ebc16c3a0a98db22f
https://git.kernel.org/stable/c/56e78b670356caab0b607e8aad4cf819a1909d07
https://git.kernel.org/stable/c/2d91e6244b69d752503b2d44020d8b0e323dbd38
https://git.kernel.org/stable/c/117d8bcaf1abc348185e8ab6a4ba9f8f516849a0