PR/48810 use cgi handler for index files

OK mrg@ martin@
KMEM_REDZONE+KMEM_POISON is supposed to detect buffer overflows. But it only
poisons memory after kmem_roundup_size(), which means that if an overflow
occurs in the page padding, it won't be detected.

Fix this by making KMEM_REDZONE independent from KMEM_POISON and making it
put a 2-byte pattern at the end of each requested buffer, and check it when
freeing memory to ensure the caller hasn't written outside the requested area.

Not enabled on DIAGNOSTIC for the moment.
PR/48944: cron ignores '?' (question mark) time field

Fix the obvious merge botch.
'miliseconds' -> 'milliseconds'.
Implement copfuncs and external memory in bpfjit.
Fix signatures of copfuncs.
Zap trailing spaces.
Remove dead code. The kernel already checks for PT_INTERP sections, and puts
their content into "itp". There's no need for re-reading the whole binary and
trying to find this section again. Just use "itp".

DEBUG_FREEBSD_ELF is now unused, so remove its references in amd64/conf/ALL
and i386/conf/ALL.
Bump SYMTAB_SPACE to allow clang to build this kernel.
Remove unused headers.
Revert previous commit.  Requested by matt@.
Allocate directly KQ_NEVENTS bytes. Otherwise a user can panic the system.

ok christos@
Do not hardcode the value. Use KQ_NEVENTS.
add a public domain notice
- Improve the comments in bpf.h and KNF a little.
- Rename bpf_ctx_t member noinit to preinited (reflects the meaning better).
Fix our iconv version for the issues that apply to us from CVE-2014-3951
(which are the:
- Consistently pass around context information using a simple pointer.
  This fixes some dereferencing bugs in Chinese character set conversions.
- Fix Simplified Chinese character set conversions by switching around the
  fields of an internal struct so it corresponds with the way variables of
  this type are initialised.
part)
Patch taken from FreeBSD and mutilated to fit.
FreeBSD credits: Manuel Mausz (reporter), Tijl Coosemans (report handler)
- bpf_validate_ext: fix memword validation in BPF_ST/BPF_STX case.
- bpf_set_extmem: check the number of words against BPF_MAX_MEMWORDS.
No functional change:
- Tabify.
- Remove trailing white spaces.
- Fix typo in comment.
Adjust NPF to the recent BPF / BPF JIT changes and make it work again.
All regression tests are happy now (hi alnsn!).
npftest: add an example in the README, fix the total in npf_test_conc().