error is not EAGAIN. Several sysctls that inspect another process use
p_candebug() for checking access right for the curproc. p_candebug()
returns EAGAIN for some reasons, in particular, for the process doing
exec() now. If execing process tries to lock Giant, we get a livelock,
because sysctl handlers are covered by Giant, and often do not sleep.
Break the livelock by dropping Giant and allowing other threads to
execute in the EAGAIN loop.
Also, do not return EAGAIN from p_candebug() when process is executing,
use more appropriate EBUSY error [1].
Reported and tested by: pho
Suggested by: rwatson [1]
Reviewed by: rwatson, des
MFC after: 1 week
whitespace) macros from p4/vimage branch.
Do a better job at enclosing all instantiations of globals
scheduled for virtualization in #ifdef VIMAGE_GLOBALS blocks.
De-virtualize and mark as const saorder_state_alive and
saorder_state_any arrays from ipsec code, given that they are never
updated at runtime, so virtualizing them would be pointless.
Reviewed by: bz, julian
Approved by: julian (mentor)
Obtained from: //depot/projects/vimage-commit2/...
X-MFC after: never
Sponsored by: NLnet Foundation, The FreeBSD Foundation
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:
mac_<object>_<method/action>
mac_<object>_check_<method/action>
The previous naming scheme was inconsistent and mostly
reversed from the new scheme. Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier. Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods. Also simplify, slightly,
some entry point names.
All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.
Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer
used, rather than the one passed via 'req', which may not reflect a
rewrite. This call to useracc() is redundant to validation performed by
later copyin()/copyout() calls, so there isn't a security issue here,
but this could technically lead to excessive validation of addresses if
the length in newlen is shorter than req.newlen.
Approved by: re (kensmith)
Reviewed by: jhb
Submitted by: Constantine A. Murenin <cnst+freebsd@bugmail.mojo.ru>
Sponsored by: Google Summer of Code 2007
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
- Remove also "MP SAFE" after prior "MPSAFE" pass. (suggested by bde)
- Remove extra blank lines in some cases.
- Add extra blank lines in some cases.
- Remove no-op comments consisting solely of the function name, the word
"syscall", or the system call name.
- Add punctuation.
- Re-wrap some comments.
system calls now enter without Giant held, and then in some cases, acquire
Giant explicitly.
Remove a number of other MPSAFE annotations in the credential code and
tweak one or two other adjacent comments.
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>
begun with a repo-copy of mac.h to mac_framework.h. sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.
This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.
Obtained from: TrustedBSD Project
Sponsored by: SPARTA
modified bit emulation traps on Alpha while holding locks in the
sysctl handler.
A better solution would be to pass a hint to the Alpha pmap code to
tell mark these pages as modified when they as they are being wired,
but that appears to be more difficult to implement.
Suggested by: jhb
MFC after: 3 days
not holding any non-sleep-able-locks locks when copyin is called.
This gets executed un-conditionally since we have no function
to wire the buffer in this direction.
Pointed out by: truckman
MFC after: 1 week
the buffer has not been wired and we are holding any non-sleep-able locks,
drop a witness warning. If the buffer has not been wired, it is possible
that the writing of the data can sleep, especially if the page is not in
memory. This can result in a number of different locking issues, including
dead locks.
MFC after: 1 week
Discussed with: rwatson
Reviewed by: jhb
an inordinate amount of synchronous console output that is fairly
undesirable on slower serial console. It's easily hit by accident
when frobbing other sysctls late at night.
sysctl routines and state. Add some code to use it for signalling the need
to downconvert a data structure to 32 bits on a 64 bit OS when requested by
a 32 bit app.
I tried to do this in a generic abi wrapper that intercepted the sysctl
oid's, or looked up the format string etc, but it was a real can of worms
that turned into a fragile mess before I even got it partially working.
With this, we can now run 'sysctl -a' on a 32 bit sysctl binary and have
it not abort. Things like netstat, ps, etc have a long way to go.
This also fixes a bug in the kern.ps_strings and kern.usrstack hacks.
These do matter very much because they are used by libc_r and other things.
somewhat clearer, but more importantly allows for a consistent naming
scheme for suser_cred flags.
The old name is still defined, but will be removed in a few days (unless I
hear any complaints...)
Discussed with: rwatson, scottl
Requested by: jhb
set it to avoid the need for a bunch of code that tests whether or
not the lock member is set to REQ_WIRED in order to determine which
length member should be used.
Fix another bug in the oldlen return value code.
Fix a potential wired memory leak if a sysctl handler uses
sysctl_wire_old_buffer() and returns an EAGAIN error to trigger
a retry.
If vslock() returns ENOMEM, sysctl_wire_old_buffer() should set
wiredlen to zero and return zero (success) so that the handler will
operate according to sysctl(3):
The size of the buffer is given by the location specified by
oldlenp before the call, and that location gives the amount
of data copied after a successful call and after a call that
returns with the error code ENOMEM.
The handler will return an ENOMEM error because the zero length
buffer will overflow.
introduction of kern_mlock() and kern_munlock() in
src/sys/kern/kern_sysctl.c 1.150
src/sys/vm/vm_extern.h 1.69
src/sys/vm/vm_glue.c 1.190
src/sys/vm/vm_mmap.c 1.179
because different resource limits are appropriate for transient and
"permanent" page wiring requests.
Retain the kern_mlock() and kern_munlock() API in the revived
vslock() and vsunlock() functions.
Combine the best parts of each of the original sets of implementations
with further code cleanup. Make the mclock() and vslock()
implementations as similar as possible.
Retain the RLIMIT_MEMLOCK check in mlock(). Move the most strigent
test, which can return EAGAIN, last so that requests that have no
hope of ever being satisfied will not be retried unnecessarily.
Disable the test that can return EAGAIN in the vslock() implementation
because it will cause the sysctl code to wedge.
Tested by: Cy Schubert <Cy.Schubert AT komquats.com>
the syscall arguments and does the suser() permission check, and
kern_mlock(), which does the resource limit checking and calls
vm_map_wire(). Split munlock() in a similar way.
Enable the RLIMIT_MEMLOCK checking code in kern_mlock().
Replace calls to vslock() and vsunlock() in the sysctl code with
calls to kern_mlock() and kern_munlock() so that the sysctl code
will obey the wired memory limits.
Nuke the vslock() and vsunlock() implementations, which are no
longer used.
Add a member to struct sysctl_req to track the amount of memory
that is wired to handle the request.
Modify sysctl_wire_old_buffer() to return an error if its call to
kern_mlock() fails. Only wire the minimum of the length specified
in the sysctl request and the length specified in its argument list.
It is recommended that sysctl handlers that use sysctl_wire_old_buffer()
should specify reasonable estimates for the amount of data they
want to return so that only the minimum amount of memory is wired
no matter what length has been specified by the request.
Modify the callers of sysctl_wire_old_buffer() to look for the
error return.
Modify sysctl_old_user to obey the wired buffer length and clean up
its implementation.
Reviewed by: bms
Now I believe it is done in the right way.
Removed some XXMAC cases, we now assume 'high' integrity level for all
sysctls, except those with CTLFLAG_ANYBODY flag set. No more magic.
Reviewed by: rwatson
Approved by: rwatson, scottl (mentor)
Tested with: LINT (compilation), mac_biba(4) (functionality)
Use pre-emption detection to avoid the need for wiring a userland buffer
when copying opaque data structures.
sysctl_wire_old_buffer() is now a no-op. Other consumers of this
API should use pre-emption detection to notice update collisions.
vslock() and vsunlock() should no longer be called by any code
and should be retired in subsequent commits.
Discussed with: pete, phk
MFC after: 1 week
go away in due course. Involuntary pre-emption means that we can't count
on wiring of pages alone for consistency when performing a SYSCTL_OUT()
bigger than PAGE_SIZE.
Discussed with: pete, phk
in the kernel, the sysctl_register() call would fail, as expected.
However, when unloading this module again, the kernel would then panic
in sysctl_unregister(). Print a message error instead.
Submitted by: Nicolai Petri <nicolai@catpipe.net>
Reviewed by: imp
Approved by: re@ (jhb)
in addition to secure level 1. The mask supports up to a secure level of 8
but only add defines through CTLFLAG_SECURE3 for now.
As per the missif in the log entry for 1.11 of ip_fw2.c which added the
secure flag to the IPFW sysctl's in the first place, change the secure
level requirement from 1 to 3 now that we have support for it.
Reviewed by: imp
With Design Suggestions by: imp
permit MAC policies to augment the security protections on sysctl()
operations. This is not really a wonderful entry point, as we
only have access to the MIB of the target sysctl entry, rather than
the more useful entry name, but this is sufficient for policies
like Biba that wish to use their notions of privilege or integrity
to prevent inappropriate sysctl modification. Affects MAC kernels
only. Since SYSCTL_LOCK isn't in sysctl.h, just kern_sysctl.c,
we can't assert the SYSCTL subsystem lockin the MAC Framework.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
sysctl_sysctl_next() to skip this sysctl. The sysctl is
still available, but doesn't appear in a "sysctl -a".
This is especially useful when you want to deprecate a sysctl,
and add a warning into it to warn users that they are using
an old interface. Without this flag, the warning would get
echoed when running "sysctl -a" (which happens at boot).
about calls to SYSCTL_OUT() made with locks held if the buffer has not
been pre-wired. SYSCTL_OUT() should not be called while holding locks,
but if this is not possible, the buffer should be wired by calling
sysctl_wire_old_buffer() before grabbing any locks.
so that the data is less likely to be inconsistent if SYSCTL_OUT() blocks.
If the data is large, wire the output buffer instead.
This is somewhat less than optimal, since the handler could skip the copy
if it knew that the data was static.
If the data is dynamic, we are still not guaranteed to get a consistent
copy since another processor could change the data while the copy is in
progress because the data is not locked. This problem could be solved if
the generic handlers had the ability to grab the proper lock before the
copy and release it afterwards.
This may duplicate work done in other sysctl handlers in the kernel which
also copy the data, possibly while a lock is held, before calling they call
a generic handler to output the data. These handlers should probably call
SYSCTL_OUT() directly.
semicolons from the end of macros:
#define FOO() bar(a,b,c);
becomes
#define FOO() bar(a,b,c)
Thus requiring the semicolon in the invocation of FOO. This is much
cleaner syntax and more consistent with expectations when writing
function-like things in source.
With both peril-sensitive sunglasses and flame-proof undies on, tighten
up some types, and work around some warnings generated by this. There
are some _horrible_ const/non-const issues in this code.
Rename memlock to sysctllock, and MEMLOCK()/MEMUNLOCK() to SYSCTL_LOCK()/
SYSCTL_UNLOCK() and related changes to make the lock names make more
sense.
Submitted by: Jonathan Mini <mini@haikugeek.com>
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@
to test req->td for NULL values and then do somewhat more bizarre things
relating to securelevel special-casing and suser checks. Remove the
testing and conditional security checks based on req->td!=NULL, and insert
a KASSERT that td != NULL. Callers to sysctl must always specify the
thread (be it kernel or otherwise) requesting the operation, or a
number of current sysctls will fail due to assumptions that the thread
exists.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
Discussed with: bde
variables. Use the -d flag in sysctl(8) to see this information.
Possible extensions to sysctl:
+ report variables that do not have a description
+ given a name, report the oid it maps to.
Note to developers: have a look at your code, there are a number of
variables which do not have a description.
Note to developers: do we want this in 4.5 ? It is a very small change
and very useful for documentation purposes.
Suggested by: Orion Hodson
sysctl_req', which describes in-progress sysctl requests. This permits
sysctl handlers to have access to the current thread, permitting work
on implementing td->td_ucred, migration of suser() to using struct
thread to derive the appropriate ucred, and allowing struct thread to be
passed down to other code, such as network code where td is not currently
available (and curproc is used).
o Note: netncp and netsmb are not updated to reflect this change, as they
are not currently KSE-adapted.
Reviewed by: julian
Obtained from: TrustedBSD Project
This stops panics on unloading modules which define their own sysctl sets.
However, this also removes the protection against somebody actually
defining a static sysctl with an oid in the range of the dynamic ones,
which would break badly if there is already a dynamic sysctl with
the requested oid.
Apparently, the algorithm for removing sysctl sets needs a bit more work.
For the present, the panic I introduced only leads to Bad Things (tm).
Submitted by: many users of -current :(
Pointy hat to: roam (myself) for not testing rev. 1.112 enough.
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
KINFO_BSDI_SYSINFO. This supposedly fixes Netscape 3.0.4 (bsdi binary)
on -current. (and is also applicable to RELENG_4)
PR: 25476
Submitted by: Philipp Mergenthaler <un1i@rz.uni-karlsruhe.de>
static entries with oid's over 100, and defining enough dynamic entries
causes an overlap.
Move the "magic" value 0x100 into <sys/sysctl.h> where it belongs.
PR: 29131
Submitted by: "Alexander N. Kabaev" <kabaev@mail.ru>
Reviewed by: -arch, -audit
MFC after: 2 weeks
Replace the a.out emulation of 'struct linker_set' with something
a little more flexible. <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.
The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).
The macros declare a strongly typed set. They return elements with the
type that you declare the set with, rather than a generic void *.
For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>). Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.
For a.out, we use the old linker_set struct.
NOTE: the item lists are no longer null terminated. This is why
the code impact is high in certain areas.
The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.
linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.
Reviewed by: eivind
more robust. They would correctly return ENOMEM for the first time when
the buffer was exhausted, but subsequent calls in this case could cause
writes ouside of the buffer bounds.
Approved by: rwatson
to the SYSCTL_ADD_FOO() macros is a constant that should be turned into
a string via the pre-processor. Instead, require it to be an explicit
string so that names can be generated on the fly.
- Make some of the char * arguments to sysctl_add_oid() const to quiet
warnings.
and remove sysctl oids at will during runtime - they don't rely on
linker sets. Also, the node oids can be referenced by more than
one kernel user, which means that it's possible to create partially
overlapping trees.
Add sysctl contexts to help programmers manage multiple dynamic
oids in convenient way.
Please see the manpages for detailed discussion, and example module
for typical use.
This work is based on ideas and code snippets coming from many
people, among them: Arun Sharma, Jonathan Lemon, Doug Rabson,
Brian Feldman, Kelly Yancey, Poul-Henning Kamp and others. I'd like
to specially thank Brian Feldman for detailed review and style
fixes.
PR: kern/16928
Reviewed by: dfr, green, phk
"rw" argument, rather than hijacking B_{READ|WRITE}.
Fix two bugs (physio & cam) resulting by the confusion caused by this.
Submitted by: Tor.Egge@fast.no
Reviewed by: alc, ken (partly)
This is a seriously beefed up chroot kind of thing. The process
is jailed along the same lines as a chroot does it, but with
additional tough restrictions imposed on what the superuser can do.
For all I know, it is safe to hand over the root bit inside a
prison to the customer living in that prison, this is what
it was developed for in fact: "real virtual servers".
Each prison has an ip number associated with it, which all IP
communications will be coerced to use and each prison has its own
hostname.
Needless to say, you need more RAM this way, but the advantage is
that each customer can run their own particular version of apache
and not stomp on the toes of their neighbors.
It generally does what one would expect, but setting up a jail
still takes a little knowledge.
A few notes:
I have no scripts for setting up a jail, don't ask me for them.
The IP number should be an alias on one of the interfaces.
mount a /proc in each jail, it will make ps more useable.
/proc/<pid>/status tells the hostname of the prison for
jailed processes.
Quotas are only sensible if you have a mountpoint per prison.
There are no privisions for stopping resource-hogging.
Some "#ifdef INET" and similar may be missing (send patches!)
If somebody wants to take it from here and develop it into
more of a "virtual machine" they should be most welcome!
Tools, comments, patches & documentation most welcome.
Have fun...
Sponsored by: http://www.rndassociates.com/
Run for almost a year by: http://www.servetheweb.com/
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.
This makes it possible to change the sysctl tree at runtime.
* Change KLD to find and register any sysctl nodes contained in the loaded
file and to unregister them when the file is unloaded.
Reviewed by: Archie Cobbs <archie@whistle.com>,
Peter Wemm <peter@netplex.com.au> (well they looked at it anyway)
It was nay'ed before committing on the grounds that this is not
the way to do it, and has been decided as such several times in
the past.
There is not point in loading gobs of ascii into the kernel when
the only use of that ascii is presentation to the user.
Next thing we'd be adding all section 4 man pages to the loaded
kernel as well.
The argument about KLD's is bogus, klds can store a file in
/usr/share/doc/sysctl/dev/foo/thisvar.txt with a description and
sysctl or other facilities can pick it up there.
Proper documentation will take several K worth of text for many
sysctl variables, we don't want that in the kernel under any
circumstances.
I will welcome any well thought out attempt at improving the
situation wrt. sysctl documentation, but this wasn't it.
