3dcaa192ac
Operations that check/update sk_state and access conn should hold lock_sock, otherwise they can race. The order of taking locks is hci_dev_lock > lock_sock > sco_conn_lock, which is how it is in connect/disconnect_cfm -> sco_conn_del -> sco_chan_del. Fix locking in sco_connect to take lock_sock around updating sk_state and conn. sco_conn_del must not occur during sco_connect, as it frees the sco_conn. Hold hdev->lock longer to prevent that. sco_conn_add shall return sco_conn with valid hcon. Make it so also when reusing an old SCO connection waiting for disconnect timeout (see __sco_sock_close where conn->hcon is set to NULL). This should not reintroduce the issue fixed in the earlier commit9a8ec9e8eb("Bluetooth: SCO: Fix possible circular locking dependency on sco_connect_cfm"), the relevant fix of releasing lock_sock in sco_sock_connect before acquiring hdev->lock is retained. These changes mirror similar fixes earlier in ISO sockets. Fixes:9a8ec9e8eb("Bluetooth: SCO: Fix possible circular locking dependency on sco_connect_cfm") Signed-off-by: Pauli Virtanen <pav@iki.fi> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.