5464c3a0e9
There are 2 call chains: a) xsk_bind --> xdp_umem_assign_dev b) unregister_netdevice_queue --> xsk_notifier with the following locking order: a) xs->mutex --> rtnl_lock b) rtnl_lock --> xdp.lock --> xs->mutex Different order of taking 'xs->mutex' and 'rtnl_lock' could produce a deadlock here. Fix that by moving the 'rtnl_lock' before 'xs->lock' in the bind call chain (a). Reported-by: syzbot+bf64ec93de836d7f4c2c@syzkaller.appspotmail.com Fixes: 455302d1c9ae ("xdp: fix hang while unregistering device bound to xdp socket") Signed-off-by: Ilya Maximets <i.maximets@samsung.com> Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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.