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struct hci_dev members conn_info_max_age, conn_info_min_age,
le_conn_max_interval, le_conn_min_interval, le_adv_max_interval,
and le_adv_min_interval can be modified from the HCI core code, as well
through debugfs.

The debugfs implementation, that's only available to privileged users,
will check for boundaries, making sure that the minimum value being set
is strictly above the maximum value that already exists, and vice-versa.

However, as both minimum and maximum values can be changed concurrently
to us modifying them, we need to make sure that the value we check is
the value we end up using.

For example, with ->conn_info_max_age set to 10, conn_info_min_age_set()
gets called from vfs handlers to set conn_info_min_age to 8.

In conn_info_min_age_set(), this goes through:
	if (val == 0 || val > hdev->conn_info_max_age)
		return -EINVAL;

Concurrently, conn_info_max_age_set() gets called to set to set the
conn_info_max_age to 7:
	if (val == 0 || val > h...