Provided by: linux-doc-2.6.15_2.6.15-23.39_all bug


       sk_chk_filter - verify socket filter code


       int sk_chk_filter  (struct sock_filter * filter, int flen);


       filter filter to verify

       flen   length of filter


       Check  the  user’s  filter  code.  If we let some ugly filter code slip
       through kaboom! The filter must contain no references or jumps that are
       out  of  range,  no illegal instructions and no backward jumps. It must
       end with a RET instruction

       Returns 0 if the rule set is legal or a negative errno code if not.