In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: mgmt: fix race in read_unconf_index_list()
read_unconf_index_list() counts unconfigured controllers before allocating
its response, then checks the device flags again while filling it.
hci_dev_list_lock stabilizes list membership, but it does not serialize the
per-device flags. During asynchronous controller setup, the worker can set
HCI_UNCONFIGURED and clear HCI_SETUP between the two passes. A controller
omitted from the allocation count can then become eligible for the fill
pass, causing an out-of-bounds write to rp->index[].
Allocate space for every device on hci_dev_list. Since list membership
cannot change while hci_dev_list_lock is held, the response remains large
enough regardless of flag transitions. The reported count and response
length still include only eligible unconfigured controllers.
