tree 5a1dbfb35f679335fbec4cbd17dfe64926db7750
parent dc87c3985e9b442c60994308a96f887579addc39
author Marcel Holtmann <marcel@holtmann.org> 1178318159 +0200
committer Marcel Holtmann <marcel@holtmann.org> 1178318159 +0200

[Bluetooth] Fix L2CAP and HCI setsockopt() information leaks

The L2CAP and HCI setsockopt() implementations have a small information
leak that makes it possible to leak kernel stack memory to userspace.

If the optlen parameter is 0, no data will be copied by copy_from_user(),
but the uninitialized stack buffer will be read and stored later. A call
to getsockopt() can now retrieve the leaked information.

To fix this problem the stack buffer given to copy_from_user() must be
initialized with the current settings.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>