48cdcb40d5
commit 25c150ac103a4ebeed0319994c742a90634ddf18 upstream. Previously, capability was checked using capable(), which verified that the caller of the ioctl system call had the required capability. In addition, the result of the check would be stored in the HCI_SOCK_TRUSTED flag, making it persistent for the socket. However, malicious programs can abuse this approach by deliberately sharing an HCI socket with a privileged task. The HCI socket will be marked as trusted when the privileged task occasionally makes an ioctl call. This problem can be solved by using sk_capable() to check capability, which ensures that not only the current task but also the socket opener has the specified capability, thus reducing the risk of privilege escalation through the previously identified vulnerability. Cc: stable@vger.kernel.org Fixes: f81f5b2db869 ("Bluetooth: Send control open and close messages for HCI raw sockets") Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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.