Commit Graph

229 Commits

Author SHA1 Message Date
mjg
c2763443b4 proc: postpone proc unlock until after reporting with kqueue
kqueue would always relock immediately afterwards.

While here drop the NULL check for list itself. The list is
always allocated.

Sponsored by:	The FreeBSD Foundation
2018-12-08 06:34:12 +00:00
markj
c293a729d8 Pass malloc flags directly through kevent(2) subroutines.
Some kevent functions have a boolean "waitok" parameter for use when
calling malloc(9).  Replace them with the corresponding malloc() flags:
the desired behaviour is known at compile-time, so this eliminates a
couple of conditional branches, and makes the code easier to read.

No functional change intended.

Reviewed by:	kib
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18318
2018-11-24 17:06:01 +00:00
markj
f578e3036e Plug some kernel memory disclosures via kevent(2).
The kernel may register for events on behalf of a userspace process,
in which case it must be careful to zero the kevent struct that will be
copied out to userspace.

Reviewed by:	kib
MFC after:	3 days
Security:	kernel stack memory disclosure
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18317
2018-11-24 17:02:31 +00:00
markj
8a86bae908 Ensure that knotes do not get registered when KQ_CLOSING is set.
KQ_CLOSING is set before draining the knotes associated with a kqueue,
so we must ensure that new knotes are not added after that point.  In
particular, some kernel facilities may register for events on behalf
of a userspace process and race with a close of the kqueue.

PR:		228858
Reviewed by:	kib
Tested by:	pho
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18316
2018-11-24 16:58:34 +00:00
markj
01ec130dc7 Lock the knlist before releasing the in-flux state in knote_fork().
Otherwise there is a window, before iteration is resumed, during which
the knote may be freed.  The in-flux state ensures that the knote will
not be removed from the knlist while locks are dropped.

PR:		228858
Reviewed by:	kib
Tested by:	pho
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18316
2018-11-24 16:41:29 +00:00
markj
0c28e8c0a6 Honour the waitok parameter in kevent_expand().
Reviewed by:	kib
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18316
2018-11-23 23:10:03 +00:00
markj
2e57d41f44 Avoid unsynchronized updates to kn_status.
kn_status is protected by the kqueue's lock, but we were updating it
without the kqueue lock held.  For EVFILT_TIMER knotes, there is no
knlist lock, so the knote activation could occur during the kn_status
update and result in KN_QUEUED being lost, in which case we'd enqueue
an already-enqueued knote, corrupting the queue.

Fix the problem by setting or clearing KN_DISABLED before dropping the
kqueue lock to call into the filter.  KN_DISABLED is used only by the
core kevent code, so there is no side effect from setting it earlier.

Reported and tested by:	Sylvain GALLIANO <sg@efficientip.com>
Reviewed by:	kib
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18060
2018-11-21 17:32:09 +00:00
markj
6994e92830 Remove KN_HASKQLOCK.
It is a write-only flag whose last use was removed in r302235.

No functional change intended.

Reviewed by:	kib
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18059
2018-11-21 17:28:10 +00:00
dab
4050420519 Allow a EVFILT_TIMER kevent to be updated.
If a timer is updated (re-added) with a different time period
(specified in the .data field of the kevent), the new time period has
no effect; the timer will not expire until the original time has
elapsed. This violates the documented behavior as the kqueue(2) man
page says (in part) "Re-adding an existing event will modify the
parameters of the original event, and not result in a duplicate
entry."

This modification, adapted from a patch submitted by cem@ to PR214987,
fixes the kqueue system to allow updating a timer entry. The
kevent timer behavior is changed to:

  * When a timer is re-added, update the timer parameters to and
    re-start the timer using the new parameters.
  * Allow updating both active and already expired timers.
  * When the timer has already expired, dequeue any undelivered events
    and clear the count of expirations.

All of these changes address the original PR and also bring the
FreeBSD and macOS kevent timer behaviors into agreement.

A few other changes were made along the way:

  * Update the kqueue(2) man page to reflect the new timer behavior.
  * Fix man page style issues in kqueue(2) diagnosed by igor.
  * Update the timer libkqueue system test to test for the updated
    timer behavior.
  * Fix the (test) libkqueue common.h file so that it includes
    config.h which defines various HAVE_* feature defines, before the
    #if tests for such variables in common.h. This enables the use of
    the actual err(3) family of functions.
  * Fix the usages of the err(3) functions in the tests for incorrect
    type of variables. Those were formerly undiagnosed due to the
    disablement of the err(3) functions (see previous bullet point).

PR:		214987
Reported by:	Brian Wellington <bwelling@xbill.org>
Reviewed by:	kib
MFC after:	1 week
Relnotes:	yes
Sponsored by:	Dell EMC
Differential Revision:	https://reviews.freebsd.org/D15778
2018-07-27 13:49:17 +00:00
mmacy
56410d49b1 kevent: annotate unused stack local 2018-05-19 05:06:18 +00:00
mmacy
e1c41612d0 filt_timerdetach: only assign to old if we're going to check it in
a KASSERT
2018-05-19 04:07:00 +00:00
mmacy
a0bd5d3d7f Eliminate the overhead of gratuitous repeated reinitialization of cap_rights
- Add macros to allow preinitialization of cap_rights_t.

- Convert most commonly used code paths to use preinitialized cap_rights_t.
  A 3.6% speedup in fstat was measured with this change.

Reported by:	mjg
Reviewed by:	oshogbo
Approved by:	sbruno
MFC after:	1 month
2018-05-09 18:47:24 +00:00
brooks
9d79658aab Move most of the contents of opt_compat.h to opt_global.h.
opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.

Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c.  A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.

Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.

Reviewed by:	kib, cem, jhb, jtl
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D14941
2018-04-06 17:35:35 +00:00
pfg
cc22a86800 sys/kern: adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 15:20:12 +00:00
jhb
bac78aa2a4 Decode kevent structures logged via ktrace(2) in kdump.
- Add a new KTR_STRUCT_ARRAY ktrace record type which dumps an array of
  structures.

  The structure name in the record payload is preceded by a size_t
  containing the size of the individual structures.  Use this to
  replace the previous code that dumped the kevent arrays dumped for
  kevent().  kdump is now able to decode the kevent structures rather
  than dumping their contents via a hexdump.

  One change from before is that the 'changes' and 'events' arrays are
  not marked with separate 'read' and 'write' annotations in kdump
  output.  Instead, the first array is the 'changes' array, and the
  second array (only present if kevent doesn't fail with an error) is
  the 'events' array.  For kevent(), empty arrays are denoted by an
  entry with an array containing zero entries rather than no record.

- Move kevent decoding tables from truss to libsysdecode.

  This adds three new functions to decode members of struct kevent:
  sysdecode_kevent_filter, sysdecode_kevent_flags, and
  sysdecode_kevent_fflags.

  kdump uses these helper functions to pretty-print kevent fields.

- Move structure definitions for freebsd11 and freebsd32 kevent
  structures to <sys/event.h> so that they can be shared with userland.
  The 32-bit structures are only exposed if _WANT_KEVENT32 is defined.
  The freebsd11 structures are only exposed if _WANT_FREEBSD11_KEVENT is
  defined.  The 32-bit freebsd11 structure requires both.

- Decode freebsd11 kevent structures in truss for the compat11.kevent()
  system call.

- Log 32-bit kevent structures via ktrace for 32-bit compat kevent()
  system calls.

- While here, constify the 'void *data' argument to ktrstruct().

Reviewed by:	kib (earlier version)
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D12470
2017-11-25 04:49:12 +00:00
mjg
2127391bd8 Add pfind_any
It looks for both regular and zombie processes. This avoids allproc relocking
previously seen with pfind -> zpfind calls.
2017-11-11 18:04:39 +00:00
kib
f855d50bc8 Do not cast struct kevent_args or struct freebsd11_kevent_args to
struct g_kevent_args.

On some architectures, e.g. PowerPC, there is additional padding in uap.

Reported and tested by:	andreast
Sponsored by:	The FreeBSD Foundation
2017-06-29 14:40:33 +00:00
kib
d7f022a3ab Add abstime kqueue(2) timers and expand struct kevent members.
This change implements NOTE_ABSTIME flag for EVFILT_TIMER, which
specifies that the data field contains absolute time to fire the
event.

To make this useful, data member of the struct kevent must be extended
to 64bit.  Using the opportunity, I also added ext members.  This
changes struct kevent almost to Apple struct kevent64, except I did
not changed type of ident and udata, the later would cause serious API
incompatibilities.

The type of ident was kept uintptr_t since EVFILT_AIO returns a
pointer in this field, and e.g. CHERI is sensitive to the type
(discussed with brooks, jhb).

Unlike Apple kevent64, symbol versioning allows us to claim ABI
compatibility and still name the new syscall kevent(2).  Compat shims
are provided for both host native and compat32.

Requested by:	bapt
Reviewed by:	bapt, brooks, ngie (previous version)
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D11025
2017-06-17 00:57:26 +00:00
kib
e36c6375d5 Style.
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
X-Differential revision:	https://reviews.freebsd.org/D11025
2017-06-16 23:41:13 +00:00
kib
5ba1b0f996 Use designated initializers for kevent_copyops.
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-03-14 09:25:01 +00:00
kib
bd6532333d Hide kev_iovlen() definition under #ifdef KTRACE, fixing build of
kernel configs without KTRACE.

Reported by:	rpokala
Sponsored by:	The FreeBSD Foundation
MFC after:	4 days
2017-03-14 08:45:52 +00:00
kib
0336a66286 Ktracing kevent(2) calls with unusual arguments might leads to an
overly large allocation requests.

When ktrace-ing io, sys_kevent() allocates memory to copy the
requested changes and reported events.  Allocations are sized by the
incoming syscall lengths arguments, which are user-controlled, and
might cause overflow in calculations or too large allocations.

Since io trace chunks are limited by ktr_geniosize, there is no sense
it even trying to satisfy unbounded allocations.  Export ktr_geniosize
and clamp the buffers sizes in advance.

PR:	217435
Reported by:	Tim Newsham <tim.newsham@nccgroup.trust>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-03-12 13:48:24 +00:00
hiren
275c6b6b14 Add kevent EVFILT_EMPTY for notification when a client has received all data
i.e. everything outstanding has been acked.

Reviewed by:	bz, gnn (previous version)
MFC after:	3 days
Sponsored by:	Limelight Networks
Differential Revision:	https://reviews.freebsd.org/D9150
2017-01-16 08:25:33 +00:00
markj
21bee8f0b6 Factor out instances of a knote detach followed by a knote_drop() call.
Reviewed by:	kib (previous version)
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D9015
2017-01-02 01:23:21 +00:00
kib
fcf2de304b Make knote KN_INFLUX state counted. This is final fix for the issue
closed by r310302 for knote().

If KN_INFLUX | KN_SCAN flags are set for the note passed to knote() or
knote_fork(), i.e. the knote is scanned, we might erronously clear
INFLUX when finishing notification.  For normal knote() it was fixed
in r310302 simply by remembering the fact that we do not own
KN_INFLUX, since there we own knlist lock and scan thread cannot clear
KN_INFLUX until we drop the lock.  For knote_fork(), the situation is
more complicated, e must drop knlist lock AKA the process lock, since
we need to register new knotes.

Change KN_INFLUX into counter and allow shared ownership of the
in-flux state between scan and knote_fork() or knote().  Both in-flux
setters need to ensure that knote is not dropped in parallel.  Added
assert about kn_influx == 1 in knote_drop() verifies that in-flux state
is not shared when knote is destroyed.

Since KBI of the struct knote is changed by addition of the int
kn_influx field, reorder kn_hook and kn_hookid to fill pad on LP64
arches [1].  This keeps sizeof(struct knote) to same 128 bytes as it
was before addition of kn_influx, on amd64.

Reviewed by:	markj
Suggested by:	markj [1]
Tested by:	pho (previous version)
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D8898
2016-12-26 19:33:40 +00:00
kib
483cf17093 Change knlist_destroy() to assert that knlist is empty instead of
accepting the wrong state and printing warning.  Do not obliterate
kl_lock and kl_unlock pointers, they are often useful for post-mortem
analysis.

Reviewed by:	markj
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
X-Differential revision:	https://reviews.freebsd.org/D8898
2016-12-26 19:28:10 +00:00
kib
dbf2cb1ad9 Style.
Reviewed by:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
X-Differential revision:	https://reviews.freebsd.org/D8898
2016-12-26 19:26:40 +00:00
kib
5da38b3b08 Some optimizations for kqueue timers.
There is no need to do two allocations per kqueue timer. Gather all
data needed by the timer callout into the structure and allocate it at
once.

Use the structure to preserve the result of timer2sbintime(), to not
perform repeated 64bit calculations in callout.

Remove tautological casts.
Remove now unused p_nexttime [1].

Noted by:	markj [1]
Reviewed by:	markj (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
X-MFC note:	do not remove p_nexttime
Differential revision:	https://reviews.freebsd.org/D8901
2016-12-25 19:49:35 +00:00
kib
8f3c939828 Some style.
Reviewed by:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
X-Differential revision:	https://reviews.freebsd.org/D8901
2016-12-25 19:38:07 +00:00
kib
fa7aa12d7b Do not clear KN_INFLUX when not owning influx state.
For notes in KN_INFLUX|KN_SCAN state, the influx bit is set by a
parallel scan.  When knote() reports event for the vnode filters,
which require kqueue unlocked, it unconditionally sets and then clears
influx to keep note around kqueue unlock.  There, do not clear influx
flag if a scan set it, since we do not own it, instead we prevent scan
from executing by holding knlist lock.

The knote_fork() function has somewhat similar problem, it might set
KN_INFLUX for scanned note, drop kqueue and list locks, and then clear
the flag after relock.  A solution there would be different enough, as
well as the test program, so close the reported issue first.

Reported and test case provided by:	yjh0502@gmail.com
PR:	214923
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2016-12-19 22:18:36 +00:00
kib
fa7f8ddf1b Switch from stdatomic.h to atomic.h for kernel.
Apparently stdatomic.h implementation for gcc 4.2 on sparc64 does not
work properly.  This effectively reverts r251803.

Reported and tested by:	lidl
Discussed with:	ed
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2016-12-16 17:41:20 +00:00
kib
b5abcbd40f Another issue reported on http://seclists.org/oss-sec/2016/q3/68 is
that struct kevent member ident has uintptr_t type, which is silently
truncated to int in the call to fget().  Explicitely check for the
valid range.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2016-07-16 13:24:58 +00:00
kib
38d067a317 When a process knote was attached to the process which is already exiting,
the knote is activated immediately.  If the exit1() later activates
knotes, such knote is attempted to be activated second time.  Detect
the condition by zeroed kn_ptr.p_proc pointer, and avoid excessive
activation.

Before r302235, such knotes were removed from the knlist immediately
upon activation.

Reported by:	truckman
Sponsored by:	The FreeBSD Foundation
Approved by:	re (gjb)
2016-07-01 20:11:28 +00:00
kib
8dad8cb1ad Fix userspace build after r302235: do not expose bool field of the
structure, change it to int.

The real fix is to sanitize user-visible definitions in sys/event.h,
e.g. the affected struct knlist is of no use for userspace programs.

Reported and tested by:	jkim
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Approved by:	re (gjb)
2016-06-27 23:34:53 +00:00
kib
15841a7afe When filt_proc() removes event from the knlist due to the process
exiting (NOTE_EXIT->knlist_remove_inevent()), two things happen:
- knote kn_knlist pointer is reset
- INFLUX knote is removed from the process knlist.
And, there are two consequences:
- KN_LIST_UNLOCK() on such knote is nop
- there is nothing which would block exit1() from processing past the
  knlist_destroy() (and knlist_destroy() resets knlist lock pointers).
Both consequences result either in leaked process lock, or
dereferencing NULL function pointers for locking.

Handle this by stopping embedding the process knlist into struct proc.
Instead, the knlist is allocated together with struct proc, but marked
as autodestroy on the zombie reap, by knlist_detach() function.  The
knlist is freed when last kevent is removed from the list, in
particular, at the zombie reap time if the list is empty.  As result,
the knlist_remove_inevent() is no longer needed and removed.

Other changes:

In filt_procattach(), clear NOTE_EXEC and NOTE_FORK desired events
from kn_sfflags for knote registered by kernel to only get NOTE_CHILD
notifications.  The flags leak resulted in excessive
NOTE_EXEC/NOTE_FORK reports.

Fix immediate note activation in filt_procattach().  Condition should
be either the immediate CHILD_NOTE activation, or immediate NOTE_EXIT
report for the exiting process.

In knote_fork(), do not perform racy check for KN_INFLUX before kq
lock is taken.  Besides being racy, it did not accounted for notes
just added by scan (KN_SCAN).

Some minor and incomplete style fixes.

Analyzed and tested by:	Eric Badger <eric@badgerio.us>
Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Approved by:	re (gjb)
Differential revision:	https://reviews.freebsd.org/D6859
2016-06-27 21:52:17 +00:00
kib
e2164fa4cf Silence false LOR report due to the taskqueue mutex and kqueue lock
named the same.

Reported by:	Doug Luce <doug@freebsd.con.com>
Sponsored by:	The FreeBSD Foundation
2016-05-24 21:13:33 +00:00
gibbs
453fdfd69a Provide high precision conversion from ns,us,ms -> sbintime in kevent
In timer2sbintime(), calculate the second and fractional second portions of
the sbintime separately. When calculating the the fractional second portion,
use a 64bit multiply to prevent excess truncation. This avoids the ~7% error
in the original conversion for ns, and smaller errors of the same type for us
and ms.

PR: 198139
Reviewed by: jhb
MFC after: 1 week
Differential Revision:    https://reviews.freebsd.org/D5397
2016-03-12 23:02:53 +00:00
markj
32d1c3375a Ensure that we test the event condition when a disabled kevent is enabled.
r274560 modified kqueue_register() to only test the event condition if the
corresponding knote is not disabled. However, this check takes place before
the EV_ENABLE flag is used to clear the KN_DISABLED flag on the knote, so
enabling a previously-disabled kevent would not result in a notification for
a triggered event. This change fixes the problem by testing for EV_ENABLED
before possibly checking the event condition.

This change also updates a kqueue regression test to exercise this case.

PR:		206368
Reviewed by:	kib
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D5307
2016-02-19 01:49:33 +00:00
markj
1945f66461 Return an error if both EV_ENABLE and EV_DISABLE are specified for a kevent.
Currently, this combination results in EV_DISABLE being ignored.

Reviewed by:	kib
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D5307
2016-02-19 01:35:01 +00:00
vangyzen
f8f3d27673 kqueue EVFILT_PROC: avoid collision between NOTE_CHILD and NOTE_EXIT
NOTE_CHILD and NOTE_EXIT return something in kevent.data: the parent
pid (ppid) for NOTE_CHILD and the exit status for NOTE_EXIT.
Do not let the two events be combined, since one would overwrite
the other's data.

PR:		180385
Submitted by:	David A. Bright <david_a_bright@dell.com>
Reviewed by:	jhb
MFC after:	1 month
Sponsored by:	Dell Inc.
Differential Revision:	https://reviews.freebsd.org/D4900
2016-01-28 20:24:15 +00:00
mjg
93991d4618 kqueue: simplify kern_kqueue by not refing/unrefing creds too early
No functional changes.
2015-09-23 12:45:08 +00:00
kib
7f517dc1f3 Exit notification for EVFILT_PROC removes knote from the knlist. In
particular, this invalidates the knote kn_link linkage, making the
SLIST_FOREACH() loop accessing undefined values (e.g. trashed by
QUEUE_MACRO_DEBUG).  If the knote is freed by other thread when kq
lock is released or when influx is cleared, e.g. by knote_scan() for
kqueue owning the knote, the iteration step would access freed memory.

Use SLIST_FOREACH_SAFE() to fix iteration.

Diagnosed by:	avg
Tested by:	avg, lstewart, pawel
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2015-09-01 14:05:29 +00:00
kib
cb97f9b456 Clean up the kqueue use of the uma KPI.
Explain why it is fine to not check for M_NOWAIT failures in
kqueue_register().  Remove unneeded check for NULL result from
waitable allocation in kqueue_scan().  uma_free(9) handles NULL
argument correctly, remove checks for NULL.  Remove useless cast and
adjust style in knote_alloc().

Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2015-09-01 13:21:32 +00:00
ed
1bf9368636 Perform cleanups in response to D3307.
- Document the kern_kevent_anonymous() function.
- Add assertions to ensure that we don't silently leave the kqueue
  linked from a file descriptor table.

Reviewed by:	jmg
Differential Revision:	https://reviews.freebsd.org/D3364
2015-08-12 17:46:26 +00:00
ed
598c6e70ce Add support for anonymous kqueues.
CloudABI's polling system calls merge the concept of one-shot polling
(poll, select) and stateful polling (kqueue). They share the same data
structures.

Extend FreeBSD's kqueue to provide support for waiting for events on an
anonymous kqueue. Unlike stateful polling, there is no need to support
timeouts, as an additional timer event could be used instead.
Furthermore, it makes no sense to use a different number of input and
output kevents. Merge this into a single argument.

Obtained from:	https://github.com/NuxiNL/freebsd
Differential Revision:	https://reviews.freebsd.org/D3307
2015-08-11 13:47:23 +00:00
ed
0698a33dea Allow the creation of kqueues with a restricted set of Capsicum rights.
On CloudABI we want to create file descriptors with just the minimal set
of Capsicum rights in place. The reason for this is that it makes it
easier to obtain uniform behaviour across different operating systems.

By explicitly whitelisting the operations, we can return consistent
error codes, but also prevent applications from depending OS-specific
behaviour.

Extend kern_kqueue() to take an additional struct filecaps that is
passed on to falloc_caps(). Update the existing consumers to pass in
NULL.

Differential Revision:	https://reviews.freebsd.org/D3259
2015-08-05 07:36:50 +00:00
kib
48ccbdea81 The si_status field of the siginfo_t, provided by the waitid(2) and
SIGCHLD signal, should keep full 32 bits of the status passed to the
_exit(2).

Split the combined p_xstat of the struct proc into the separate exit
status p_xexit for normal process exit, and signalled termination
information p_xsig.  Kernel-visible macro KW_EXITCODE() reconstructs
old p_xstat from p_xexit and p_xsig.  p_xexit contains complete status
and copied out into si_status.

Requested by:	Joerg Schilling
Reviewed by:	jilles (previous version), pho
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
2015-07-18 09:02:50 +00:00
mjg
d7bc9285a6 Implement lockless resource limits.
Use the same scheme implemented to manage credentials.

Code needing to look at process's credentials (as opposed to thred's) is
provided with *_proc variants of relevant functions.

Places which possibly had to take the proc lock anyway still use the proc
pointer to access limits.
2015-06-10 10:48:12 +00:00
dchagin
e7fb40a8a0 For future use in the Linuxulator:
1. Add a kern_kqueue() counterpart for kqueue() with flags parameter.

2. Be a bit secure. To avoid a double fp lookup add a kern_kevent_fp()
counterpart for kern_kevent() with file pointer parameter instead
of file descriptor an pass the buck to it.

Suggested by: mjg [2]

Differential Revision:	https://reviews.freebsd.org/D1091
Reviewed by:	trasz
2015-05-24 16:36:29 +00:00
jkim
318c4f97e6 CALLOUT_MPSAFE has lost its meaning since r141428, i.e., for more than ten
years for head.  However, it is continuously misused as the mpsafe argument
for callout_init(9).  Deprecate the flag and clean up callout_init() calls
to make them more consistent.

Differential Revision:	https://reviews.freebsd.org/D2613
Reviewed by:	jhb
MFC after:	2 weeks
2015-05-22 17:05:21 +00:00