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We currently do not allow using hci_conn from outside of HCI-core. However, several other users could make great use of it. This includes HIDP, rfcomm and all other sub-protocols that rely on an active connection. Hence, we now introduce hci_conn ref-counting. We currently never call get_device(). put_device() is exclusively used in hci_conn_del_sysfs(). Hence, we currently never have a greater device-refcnt than 1. Therefore, it is safe to move the put_device() call from hci_conn_del_sysfs() to hci_conn_del() (it's the only caller). In fact, this even fixes a "use-after-free" bug as we access hci_conn after calling hci_conn_del_sysfs() in hci_conn_del(). From now on we can add references to hci_conn objects in other layers (like l2cap_sock, HIDP, rfcomm, ...) and grab a reference via hci_conn_get(). This does _not_ guarantee, that the connection is still alive. But, this isn't what we want. We can simply lock the hci_conn device and use "device_is_registered(hci_conn->dev)" to test that. However, this is hardly necessary as outside users should never rely on the HCI connection to be alive, anyway. Instead, they should solely rely on the device-object to be available. But if sub-devices want the hci_conn object as sysfs parent, they need to be notified when the connection drops. This will be introduced in later patches with l2cap_users. Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Acked-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> |
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| .. | ||
| bnep | ||
| cmtp | ||
| hidp | ||
| rfcomm | ||
| a2mp.c | ||
| af_bluetooth.c | ||
| amp.c | ||
| hci_conn.c | ||
| hci_core.c | ||
| hci_event.c | ||
| hci_sock.c | ||
| hci_sysfs.c | ||
| Kconfig | ||
| l2cap_core.c | ||
| l2cap_sock.c | ||
| lib.c | ||
| Makefile | ||
| mgmt.c | ||
| sco.c | ||
| smp.c | ||