Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Move SysV IPC freebsd32 compat shims helpers from freebsd32_misc.c to
sysv_ipc.c.

Reviewed by: jhb
MFC after: 2 weeks

Change the ABI of some of the structures used by the SYSV IPC API:
- The uid/cuid members of struct ipc_perm are now uid_t instead of unsigned
short.
- The gid/cgid members of struct ipc_perm are now gid_t instead of unsigned
short.
- The mode member of struct ipc_perm is now mode_t instead of unsigned short
(this is merely a style bug).
- The rather dubious padding fields for ABI compat with SV/I386 have been
removed from struct msqid_ds and struct semid_ds.
- The shm_segsz member of struct shmid_ds is now a size_t instead of an
int. This removes the need for the shm_bsegsz member in struct
shmid_kernel and should allow for complete support of SYSV SHM regions
>= 2GB.
- The shm_nattch member of struct shmid_ds is now an int instead of a
short.
- The shm_internal member of struct shmid_ds is now gone. The internal
VM object pointer for SHM regions has been moved into struct
shmid_kernel.
- The existing __semctl(), msgctl(), and shmctl() system call entries are
now marked COMPAT7 and new versions of those system calls which support
the new ABI are now present.
- The new system calls are assigned to the FBSD-1.1 version in libc. The
FBSD-1.0 symbols in libc now refer to the old COMPAT7 system calls.
- A simplistic framework for tagging system calls with compatibility
symbol versions has been added to libc. Version tags are added to
system calls by adding an appropriate __sym_compat() entry to
src/lib/libc/incldue/compat.h. [1]

PR: kern/16195 kern/113218 bin/129855
Reviewed by: arch@, rwatson
Discussed with: kan, kib [1]

Eliminate now-unused SUSER_ALLOWJAIL arguments to priv_check_cred(); in
some cases, move to priv_check() if it was an operation on a thread and
no other flags were present.

Eliminate caller-side jail exception checking (also now-unused); jail
privilege exception code now goes solely in kern_jail.c.

We can't yet eliminate suser() due to some cases in the KAME code where
a privilege check is performed and then used in many different deferred
paths. Do, however, move those prototypes to priv.h.

Reviewed by: csjp
Obtained from: TrustedBSD Project

Sync up PRIV_IPC_{ADMIN,READ,WRITE} priv checks in ipcperm() with
kern_jail.c: allow jailed root these privileges. This only has an
effect if System V IPC is administratively enabled for the jail.

Restore sysv_ipc.c:1.30, which was backed out due to interactions with
System V shared memory, now believed fixed in sysv_shm.c:1.109:

date: 2006/11/06 13:42:01; author: rwatson; state: Exp; lines: +65 -37
Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges. These may
require some future tweaking.

Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>

This restores fine-grained privilege support to System V IPC.

PR: 106078

For now, back out sysv_ipc.c:1.30, which caused shmget() with odd mode
arguments to fail. The mode field for shmget() appears to have undefined
meaning in the context of an already-present IPC object, but applications
appear to assume any arbitrary passed value will be ignored. I had hoped
to revisit this more quickly, but am removing the change for now to
prevent toe-stubbing.

Reported by: JAroslav Suchanek <jarda at grisoft dot cz>
PR: kern/106078

Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges. These may
require some future tweaking.

Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>

/* -> /*- for copyright notices, minor format tweaks as necessary

Add an annotation to the comment for sysv_ipc.c to indicate that the
MAC Framework doesn't require checks in ipcperm() because checks
relating to System V IPC will be performed in individual IPC
implementations.

Use __FBSDID().

Attempt to further comment and clarify System V IPC logic: document
why certain exceptions are made, note an inconsistency between
FreeBSD and some other implementations regarding IPC_M, and let
suser() generate our EPERM rather than forcing it ourselves.
Remove a carriage return that crept in in the last commit.

Reviewed by: gordon
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories

Attempt to marginally de-obfuscate sections of the System V IPC access
control logic.

Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories

It is possible for an active aio to prevent shared memory from being
dereferenced when a process exits due to the vmspace ref-count being
bumped. Change shmexit() and shmexit_myhook() to take a vmspace instead
of a process and call it in vmspace_dofree(). This way if it is missed
in exit1()'s early-resource-free it will still be caught when the zombie is
reaped.

Also fix a potential race in shmexit_myhook() by NULLing out
vmspace->vm_shm prior to calling shm_delete_mapping() and free().

MFC after: 7 days

Change the suser() API to take advantage of td_ucred as well as do a
general cleanup of the API. The entire API now consists of two functions
similar to the pre-KSE API. The suser() function takes a thread pointer
as its only argument. The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0. The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.

Discussed on: smp@

Simple p_ucred -> td_ucred changes to start using the per-thread ucred
reference.

Eliminate semexit_hook using at_exit(9) and rm_at_exit(9).

Reviewed by: alfred

o Remove (struct proc *p = td->td_proc) indirection in ipcperm(),
as suser_td(td) works as well as suser_xxx(NULL, p->p_ucred, 0);
This simplifies upcoming changes to suser(), and causes this code
to use the right credential (well, largely) once the td->td_ucred
changes are complete. There remains some redundancy and oddness
in this code, which should be rethought after the next batch of
suser and credential changes.

o Move suser() calls in kern/ to using suser_xxx() with an explicit
credential selection, rather than reference via a thread or process
pointer. This is part of a gradual migration to suser() accepting
a struct ucred instead of a struct proc, simplifying the reference
and locking semantics of suser().

Obtained from: TrustedBSD Project

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha

sysvipc loadable.

new syscall entry lkmressys - "reserved loadable syscall"

Make syscall_register allow overwriting of such entries (lkmressys).

Move suser() and suser_xxx() prototypes and a related #define from
<sys/proc.h> to <sys/systm.h>.

Correctly document the #includes needed in the manpage.

Add one now needed #include of <sys/systm.h>.
Remove the consequent 48 unused #includes of <sys/proc.h>.

Remove the undocumented, flawed, broken-as-designed semconfig() syscall.

In 'ipcperm()', only call 'suser()' if it is actually required.
Previously, it was being called whether it was needed or not and the
ASU flag was being set (as a side affect of calling 'suser()') in
cases where superuser privileges were not actually needed. This was
all pointed out to me by Bruce Evans.

Reviewed by: bde

Fix a superuser credential check.

Reviewed by: phk
Approved by: jkh

$Id$ -> $FreeBSD$

Change suser_xxx() to suser() where it applies.

Suser() simplification:

1:
s/suser/suser_xxx/

2:
Add new function: suser(struct proc *), prototyped in <sys/proc.h>.

3:
s/suser_xxx(\([a-zA-Z0-9_]*\)->p_ucred, \&\1->p_acflag)/suser(\1)/

The remaining suser_xxx() calls will be scrutinized and dealt with
later.

There may be some unneeded #include <sys/cred.h>, but they are left
as an exercise for Bruce.

More changes to the suser() API will come along with the "jail" code.

Use suser() to determine super-user-ness, don't examine cr_uid directly.

Removed an unused #include. Added an unsed #include of <sys/ucred.h>
to prepare for not including it in <sys/param.h>. Moved conditionally
used #includes inside an ifdef.

Move the "retval" (3rd) parameter from all syscall functions and put
it in struct proc instead.

This fixes a boatload of compiler warning, and removes a lot of cruft
from the sources.

I have not removed the /*ARGSUSED*/, they will require some looking at.

libkvm, ps and other userland struct proc frobbing programs will need
recompiled.

Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

kern_descrip.c: add fdshare()/fdcopy()
kern_fork.c: add the tiny bit of code for rfork operation.
kern/sysv_*: shmfork() takes one less arg, it was never used.
sys/shm.h: drop "isvfork" arg from shmfork() prototype
sys/param.h: declare rfork args.. (this is where OpenBSD put it..)
sys/filedesc.h: protos for fdshare/fdcopy.
vm/vm_mmap.c: add minherit code, add rounding to mmap() type args where
it makes sense.
vm/*: drop unused isvfork arg.

Note: this rfork() implementation copies the address space mappings,
it does not connect the mappings together. ie: once the two processes
have split, the pages may be shared, but the address space is not. If one
does a mmap() etc, it does not appear in the other. This makes it not
useful for pthreads, but it is useful in it's own right for having
light-weight threads in a static shared address space.

Obtained from: Original by Ron Minnich, extended by OpenBSD

(gulp!) reran makesyscalls..

sysv_ipc.c: add stub functions that either simply return (for the hooks
in kern_fork/kern_exit) or log() a messgae and call enosys() (for the
syscalls). sysv_ipc.c will become "standard" in conf/files and has
#ifs for all the permutations.

Somehow managed to miss these four files when converting the SYSV IPC
options over to the new style.

Added SYSV ipcs.

Obtained from: NetBSD and FreeBSD-1.1.5