[0/1] Add a sysctl to disable io_uring system-wide

Message

Matteo Rizzo June 27, 2023, noon UTC

Over the last few years we've seen many critical vulnerabilities in
io_uring (https://goo.gle/limit-iouring) which could be exploited by
an unprivileged process. There is currently no way to disable io_uring
system-wide except by compiling it out of the kernel entirely. The only
way to prevent a process from accessing io_uring is to use a seccomp
filter, but seccomp cannot be applied system-wide. This patch introduces a
new sysctl which disables the creation of new io_uring instances
system-wide. This gives system admins a way to reduce the kernel's attack
surface on systems where io_uring is not used.


Matteo Rizzo (1):
  Add a new sysctl to disable io_uring system-wide

 Documentation/admin-guide/sysctl/kernel.rst | 14 ++++++++++++
 io_uring/io_uring.c                         | 24 +++++++++++++++++++++
 2 files changed, 38 insertions(+)