9c24cc6a9d
commit 6f7c41374b62fd80bbd8aae3536c43688c54d95e upstream. syzbot is reporting that use of SOCKET_I()->sk from open() can result in use after free problem [1], for socket's inode is still reachable via /proc/pid/fd/n despite destruction of SOCKET_I()->sk already completed. At first I thought that this race condition applies to only open/getattr permission checks. But James Morris has pointed out that there are more permission checks where this race condition applies to. Thus, get rid of tomoyo_get_socket_name() instead of conditionally bypassing permission checks on sockets. As a side effect of this patch, "socket:[family=\$:type=\$:protocol=\$]" in the policy files has to be rewritten to "socket:[\$]". [1] https://syzkaller.appspot.com/bug?id=73d590010454403d55164cca23bd0565b1eb3b74 Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: syzbot <syzbot+0341f6a4d729d4e0acf1@syzkaller.appspotmail.com> Reported-by: James Morris <jmorris@namei.org> 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.