[PATCH 00/14] Make the user mode driver code a better citizen

[Eric W. Biederman]

Asking for people to fix their bugs in this user mode driver code has
been remarkably unproductive.  So here are my bug fixes.

I have tested them by booting with the code compiled in and
by killing "bpfilter_umh" and running iptables -vnL to restart
the userspace driver.

I have split the changes into small enough pieces so they should be
easily readable and testable.  

The changes lean into the preexisting interfaces in the kernel and
remove special cases for user mode driver code in favor of solutions
that don't need special cases.  This results in smaller code with
fewer bugs.

At a practical level this removes the maintenance burden of the
user mode drivers from the user mode helper code and from exec as
the special cases are removed.

Similarly the LSM interaction bugs are fixed by not having unnecessary
special cases for user mode drivers.

Please let me know if you see any bugs.  Once the code review is
finished I plan to take this through my tree.

Eric W. Biederman (14):
      umh: Capture the pid in umh_pipe_setup
      umh: Move setting PF_UMH into umh_pipe_setup
      umh: Rename the user mode driver helpers for clarity
      umh: Remove call_usermodehelper_setup_file.
      umh: Separate the user mode driver and the user mode helper support
      umd: For clarity rename umh_info umd_info
      umd: Rename umd_info.cmdline umd_info.driver_name
      umd: Transform fork_usermode_blob into fork_usermode_driver
      umh: Stop calling do_execve_file
      exec: Remove do_execve_file
      bpfilter: Move bpfilter_umh back into init data
      umd: Track user space drivers with struct pid
      bpfilter: Take advantage of the facilities of struct pid
      umd: Remove exit_umh

 fs/exec.c                        |  38 ++------
 include/linux/binfmts.h          |   1 -
 include/linux/bpfilter.h         |   7 +-
 include/linux/sched.h            |   9 --
 include/linux/umd.h              |  18 ++++
 include/linux/umh.h              |  15 ----
 kernel/Makefile                  |   1 +
 kernel/exit.c                    |   1 -
 kernel/umd.c                     | 183 +++++++++++++++++++++++++++++++++++++++
 kernel/umh.c                     | 171 +-----------------------------------
 net/bpfilter/bpfilter_kern.c     |  38 ++++----
 net/bpfilter/bpfilter_umh_blob.S |   2 +-
 net/ipv4/bpfilter/sockopt.c      |  20 +++--
 13 files changed, 249 insertions(+), 255 deletions(-)

Eric