From: Aaron Thompson dev@aaront.org

If bt_init() fails, the debugfs directory currently is not removed. If the module is loaded again after that, the debugfs directory is not set up properly due to the existing directory.

# modprobe bluetooth # ls -laF /sys/kernel/debug/bluetooth total 0 drwxr-xr-x 2 root root 0 Sep 27 14:26 ./ drwx------ 31 root root 0 Sep 27 14:25 ../ -r--r--r-- 1 root root 0 Sep 27 14:26 l2cap -r--r--r-- 1 root root 0 Sep 27 14:26 sco # modprobe -r bluetooth # ls -laF /sys/kernel/debug/bluetooth ls: cannot access '/sys/kernel/debug/bluetooth': No such file or directory #

# modprobe bluetooth modprobe: ERROR: could not insert 'bluetooth': Invalid argument # dmesg | tail -n 6 Bluetooth: Core ver 2.22 NET: Registered PF_BLUETOOTH protocol family Bluetooth: HCI device and connection manager initialized Bluetooth: HCI socket layer initialized Bluetooth: Faking l2cap_init() failure for testing NET: Unregistered PF_BLUETOOTH protocol family # ls -laF /sys/kernel/debug/bluetooth total 0 drwxr-xr-x 2 root root 0 Sep 27 14:31 ./ drwx------ 31 root root 0 Sep 27 14:26 ../ #

# modprobe bluetooth # dmesg | tail -n 7 Bluetooth: Core ver 2.22 debugfs: Directory 'bluetooth' with parent '/' already present! NET: Registered PF_BLUETOOTH protocol family Bluetooth: HCI device and connection manager initialized Bluetooth: HCI socket layer initialized Bluetooth: L2CAP socket layer initialized Bluetooth: SCO socket layer initialized # ls -laF /sys/kernel/debug/bluetooth total 0 drwxr-xr-x 2 root root 0 Sep 27 14:31 ./ drwx------ 31 root root 0 Sep 27 14:26 ../ #

Cc: stable@vger.kernel.org Fixes: ffcecac6a738 ("Bluetooth: Create root debugfs directory during module init") Signed-off-by: Aaron Thompson dev@aaront.org --- net/bluetooth/af_bluetooth.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c index 67604ccec2f4..0d4b171b939a 100644 --- a/net/bluetooth/af_bluetooth.c +++ b/net/bluetooth/af_bluetooth.c @@ -825,6 +825,7 @@ static int __init bt_init(void) bt_sysfs_cleanup(); cleanup_led: bt_leds_cleanup(); + debugfs_remove_recursive(bt_debugfs); return err; }