net: bpfilter: fix two bugs in bpfilter

This patches fix two bugs in bpfilter which are related in iptables command.

First patch adds error handling code for bpfilter_umh. When error occurred in bpfilter_umh, bpfilter is stopped. then it never be restarted. it makes failing iptables command. This patch adds restart bpfilter_umh routine.

Second patch ensures that bpfilter.ko module will not removed while it's being used.
bpfilter.ko is not protected by lock or module reference counter. Therefore that can be removed while module is being used. In order to protect that, mutex is used.

Taehee Yoo (2):
net: bpfilter: restart bpfilter_umh when error occurred
net: bpfilter: disallow to remove bpfilter module while being used

 include/linux/bpfilter.h         | 16 +++++++++++---
 net/bpfilter/bpfilter_kern.c     | 35 +++++++++++++++--------------
 net/bpfilter/bpfilter_umh_blob.S |  2 +-
 net/ipv4/bpfilter/sockopt.c      | 38 +++++++++++++++++++++++---------
 4 files changed, 60 insertions(+), 31 deletions(-)

2.17.1