Commit Graph

548 Commits

Author SHA1 Message Date
Mateusz Guzik
b249ce48ea vfs: drop the mostly unused flags argument from VOP_UNLOCK
Filesystems which want to use it in limited capacity can employ the
VOP_UNLOCK_FLAGS macro.

Reviewed by:	kib (previous version)
Differential Revision:	https://reviews.freebsd.org/D21427
2020-01-03 22:29:58 +00:00
Jeff Roberson
61a74c5ccd schedlock 1/4
Eliminate recursion from most thread_lock consumers.  Return from
sched_add() without the thread_lock held.  This eliminates unnecessary
atomics and lock word loads as well as reducing the hold time for
scheduler locks.  This will eventually allow for lockless remote adds.

Discussed with:	kib
Reviewed by:	jhb
Tested by:	pho
Differential Revision:	https://reviews.freebsd.org/D22626
2019-12-15 21:11:15 +00:00
Edward Tomasz Napierala
34ad5ac242 Add kern_kill() and use it in Linuxulator. It's just a cleanup,
no functional changes.

Reviewed by:	kib
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D22645
2019-12-13 18:44:02 +00:00
Konstantin Belousov
0cc9fb7551 Only return EPERM from kill(-pid) when no process was signalled.
As mandated by POSIX.  Also clarify the kill(2) manpage.

While there, restructure the code in killpg1() to use helper which
keeps overall state of the process list iteration in the killpg1_ctx
structued, later used to infer the error returned.

Reported by:	amdmi3
Reviewed by:	jilles
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D22621
2019-12-07 18:07:49 +00:00
Konstantin Belousov
ef401a8558 Requested and tested by: kevans
Reviewed by:	kevans (previous version), markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D22546
2019-11-27 20:33:53 +00:00
Kyle Evans
079c5b9ed8 rfork(2): add RFSPAWN flag
When RFSPAWN is passed, rfork exhibits vfork(2) semantics but also resets
signal handlers in the child during creation to avoid a point of corruption
of parent state from the child.

This flag will be used by posix_spawn(3) to handle potential signal issues.

Reviewed by:	jilles, kib
Differential Revision:	https://reviews.freebsd.org/D19058
2019-09-25 19:20:41 +00:00
Konstantin Belousov
7e097daa93 Only enable COMPAT_43 changes for syscalls ABI for a.out processes.
Reviewed by:	imp, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D21200
2019-08-11 19:16:07 +00:00
Mark Johnston
918988576c Avoid relying on header pollution from sys/refcount.h.
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
2019-07-29 20:26:01 +00:00
Eric van Gyzen
9d3ecb7e62 Adds signal number format to kern.corefile
Add format capability to core file names to include signal
that generated the core. This can help various validation workflows
where all cores should not be considered equally (SIGQUIT is often
intentional and not an error unlike SIGSEGV or SIGBUS)

Submitted by:	David Leimbach (leimy2k@gmail.com)
Reviewed by:	markj
MFC after:	1 week
Relnotes:	sysctl kern.corefile can now include the signal number
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D20970
2019-07-16 15:51:09 +00:00
Konstantin Belousov
89f2ab0608 Switch to check for effective user id in r349320, and disable dumping
into existing files for sugid processes.

Despite using real user id pronounces the intent, it actually breaks
suid coredumps, while not making any difference for non-sugid
processes.  The reason for the breakage is that non-existent core file
is created with the effective uid (unless weird hacks like SUIDDIR are
configured).

Then, if user enabled kern.sugid_coredump, core dumping should not
overwrite core files owned by effective uid, but we cannot pretend to
use real uid for dumping.

PR:	68905
admbugs:	358
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-06-23 21:15:31 +00:00
Konstantin Belousov
7a29e0bf96 coredump: avoid writing to core files not owned by the real user.
Reported by: blake frantz <trew@hick.org>
PR:	68905
admbugs:	358
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-06-23 18:35:11 +00:00
Konstantin Belousov
ab74c84333 Do not go into sleep in sleepq_catch_signals() when SIGSTOP from
PT_ATTACH was consumed.

In particular, do not clear TDP_FSTP in ptracestop() if td_wchan is
non-NULL. Leave it to sleepq_catch_signal() to clear and convert zero
return code to EINTR.

Otherwise, per submitter report, if the PT_ATTACH SIGSTOP was
delivered right after the thread was added to the sleepqueue but not
yet really sleep, and cursig() caused debugger attach, the thread
sleeps instead of returning to the userspace boundary with EINTR.

PR: 231445
Reported by:	Efi Weiss <valmarelox@gmail.com>
Reviewed by:	markj
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D20381
2019-05-29 14:05:27 +00:00
John Baldwin
83bf5ec367 Remove p_code from struct proc.
Contrary to the comments, it was never used by core dumps or
debuggers.  Instead, it used to hold the signal code of a pending
signal, but that was replaced by the 'ksi_code' member of ksiginfo_t
when signal information was reworked in 7.0.

Reviewed by:	kib
Differential Revision:	https://reviews.freebsd.org/D20047
2019-04-25 18:42:07 +00:00
Kristof Provost
de2d0d297a Remove unneeded NULL check for td_ucred
td_ucred is always set, so we don't need the ternary expression to check for
it.
2019-01-04 21:12:17 +00:00
Kristof Provost
4ae4822d6a Simplify jail ID printing on process exit
As suggested by kib@, we don't need to check p_ucred, because that's only NULL
during process creation, and cr_prison is never NULL.
2018-12-29 21:36:02 +00:00
Kristof Provost
af8becca15 Make kernel print jail ID when logging a process exit
Kernel now includes jail ID when logging a process exit. jid is 0 for unjailed
processes.

Submitted by:	Marie Helene Kvello-Aune <freebsd@mhka.no>
Relnotes:	yes
Sponsored by:	Modirum MDPay
Differential Revision:	https://reviews.freebsd.org/D18618
2018-12-29 14:48:51 +00:00
John Baldwin
c5786670ac Don't report stale signal information for non-signal events in ptrace_lwpinfo.
Once a signal's siginfo was copied to 'td_si' as part of the signal
exchange in issignal(), it was never cleared.  This caused future
thread events that are reported as SIGTRAP events without signal
information to report the stale siginfo in 'td_si'.  For example, if a
debugger created a new process and used SIGSTOP to stop it after
PT_ATTACH, future system call entry / exit events would set PL_FLAG_SI
with the SIGSTOP siginfo in pl_siginfo.  This broke 'catch syscall' in
current versions of gdb as it assumed PL_FLAG_SI with SIGTRAP
indicates a breakpoint or single step trap.

Reviewed by:	kib
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D18487
2018-12-10 19:39:24 +00:00
Konstantin Belousov
affd918514 Improve sigonstack().
Avoid relying on unsigned overflow for the test.
Simplify expressions to avoid duplicate check for the range.
Style.
Add herald comment.

Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D18361
2018-11-27 19:50:58 +00:00
Konstantin Belousov
a70e9a1388 Swap in WKILLED processes.
Swapped-out process that is WKILLED must be swapped in as soon as
possible.  The reason is that such process can be killed by OOM and
its pages can be only freed if the process exits.  To exit, the kernel
stack of the process must be mapped.

When allocating pages for the stack of the WKILLED process on swap in,
use VM_ALLOC_SYSTEM requests to increase the chance of the allocation
to succeed.

Add counter of the swapped out processes to avoid unneeded iteration
over the allprocs list when there is no work to do, reducing the
allproc_lock ownership.

Reviewed by:	alc, markj (previous version)
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D16489
2018-08-04 20:45:43 +00:00
Alan Somers
6040822c4e Make timespecadd(3) and friends public
The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have grown at least 28 syscalls that use timespecs in some
way, leading many programs both inside and outside of the base system to
redefine those macros. It's better just to make the definitions public.

Our kernel currently defines two-argument versions of timespecadd and
timespecsub.  NetBSD, OpenBSD, and FreeDesktop.org's libbsd, however, define
three-argument versions.  Solaris also defines a three-argument version, but
only in its kernel.  This revision changes our definition to match the
common three-argument version.

Bump _FreeBSD_version due to the breaking KPI change.

Discussed with:	cem, jilles, ian, bde
Differential Revision:	https://reviews.freebsd.org/D14725
2018-07-30 15:46:40 +00:00
Mariusz Zaborski
f1fe1e020f Extend amount of possible coredumps from 10 to 100000 when using index format.
The amount of digits in the name of corefile is assigned dynamically.

Reviewed by:	kib
Differential Revision:	https://reviews.freebsd.org/D16118
2018-07-15 17:10:12 +00:00
Mariusz Zaborski
6cad1a5d14 Add description to debug.ncores sysctl.
Reviewed by:	bcr
Differential Revision:	https://reviews.freebsd.org/D16123
2018-07-04 17:06:51 +00:00
Mariusz Zaborski
0dea6e3c98 core(5): overwrite the oldest core dump
The '%I' format in the kern.corefile sysctl limits the number of
core files that a process can generate to the number stored in the
debug.ncores sysctl. The '%I' format is replaced by the single digit
index. Previously, if all indexes were taken the kernel would overwrite
only a core file with the highest index in a filename.
Currently the system will create a new core file if there is a free
index or if all slots are taken it will overwrite the oldest one.

Reviewed by:	kib(code), bcr (updating)
Differential Revision:	https://reviews.freebsd.org/D15991
Differential Revision:	https://reviews.freebsd.org/D16084
2018-07-01 17:28:46 +00:00
Warner Losh
349fcda430 Fix devctl generation for core files.
We have a problem with vn_fullpath_global when the file exists. Work
around it by printing the full path if the core file name starts with /,
or current working directory followed by the filename if not.

Sponsored by: Netflix
Differential Review: https://reviews.freebsd.org/D16026
2018-06-27 04:11:09 +00:00
Konstantin Belousov
6e22bbf66e fork: avoid endless wait with PTRACE_FORK and RFSTOPPED.
An RFSTOPPED thread can't clean TDB_STOPATFORK, which is done in the
fork_return() in its context, so parent is stuck forever.  Triggered
when trying to ptrace linux process.  Instead of waiting for the new
thread to clear TDB_STOPATFORK, tag it as traced and reparent to the
debugger in do_fork(), and let it only notify the debugger when run.

Submitted by:	Yanko Yankulov <yanko.yankulov@gmail.com>
Reviewed by:	jhb
MFC after:	1 week
X-MFC-Note:	keep p_dbgwait placeholder intact
Differential revision:	https://reviews.freebsd.org/D15857
2018-06-21 21:12:49 +00:00
Matt Macy
ddd4d15ecd signotify: don't create a stack local that isn't used on non-debug builds 2018-05-19 03:57:41 +00:00
Matt Macy
cbd92ce62e 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 Davis
6469bdcdb6 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
Konstantin Belousov
fb441a8829 Fix several leaks of kernel stack data through paddings.
It is random collection of fixes for issues not yet corrected,
reported at https://tsyrklevi.ch/clang_analyzer/freebsd_013017/. Many
issues from that list were already corrected. Most of them are for
compat32, old compat32 or affect both primary host ABI and compat32.

The freebsd32_kldstat(), for instance, was already fixed by using
malloc(M_ZERO).  Patch includes correction to report the supplied
version back, which is just pedantic.

Reviewed by:	brooks, emaste (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D14868
2018-03-27 18:05:51 +00:00
Mateusz Guzik
681a1b752c Make killpg1 perform process validity checks without proc lock held. 2018-02-20 10:52:07 +00:00
Mark Johnston
6026dcd7ca Add support for zstd-compressed user and kernel core dumps.
This works similarly to the existing gzip compression support, but
zstd is typically faster and gives better compression ratios.

Support for this functionality must be configured by adding ZSTDIO to
one's kernel configuration file. dumpon(8)'s new -Z option is used to
configure zstd compression for kernel dumps. savecore(8) now recognizes
and saves zstd-compressed kernel dumps with a .zst extension.

Submitted by:	cem (original version)
Relnotes:	yes
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D13101,
			https://reviews.freebsd.org/D13633
2018-02-13 19:28:02 +00:00
Mark Johnston
78f57a9cde Generalize the gzio API.
We currently use a set of subroutines in kern_gzio.c to perform
compression of user and kernel core dumps. In the interest of adding
support for other compression algorithms (zstd) in this role without
complicating the API consumers, add a simple compressor API which can be
used to select an algorithm.

Also change the (non-default) GZIO kernel option to not enable
compressed user cores by default. It's not clear that such a default
would be desirable with support for multiple algorithms implemented,
and it's inconsistent in that it isn't applied to kernel dumps.

Reviewed by:	cem
Differential Revision:	https://reviews.freebsd.org/D13632
2018-01-08 21:27:41 +00:00
Pedro F. Giffuni
51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

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.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00
Mateusz Guzik
537d0fb138 Use pfind_any in linux_rt_sigqueueinfo and kern_sigqueue 2017-11-11 18:10:09 +00:00
Mateusz Guzik
6e1619dae3 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
Konstantin Belousov
e9445808a8 Re-evaluate thread' signal mask after ptracestop().
The stop drops process lock, which allows the signal mask to be
changed and our selected signal might become blocked, i.e. should be
returned to the process queue instead of delivery.

Also, for the existing check of the process no longer having an
attached debugger, we should not loose the signal, but requeue it.

Reported and tested by:	bdrewery
Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-10-16 20:21:51 +00:00
Konstantin Belousov
cd735d8f5a Improve assertion that an ignored or blocked signal is not delivered.
Split two conditions into separate asserts.  Print additional details,
like the signal number and action value.

Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-10-16 20:15:19 +00:00
Konstantin Belousov
0167b33b81 Style.
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-10-16 20:11:29 +00:00
Konstantin Belousov
7ceeb35bd8 Make it possible to request nosys logging to console.
New kern.lognosys values are
1 - log to ctty
2 - log to console
3 - log to both.

Inspired by:	eugen
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-07-27 20:45:41 +00:00
Konstantin Belousov
f5a077c390 Print unimplemented syscall number to the ctty on SIGSYS, if enabled
by the knob kern.lognosys.

Discussed with:	imp
Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	3 weeks
X-Differential revision:	https://reviews.freebsd.org/D11080
2017-06-12 21:11:11 +00:00
Ed Maste
3e85b721d6 Remove register keyword from sys/ and ANSIfy prototypes
A long long time ago the register keyword told the compiler to store
the corresponding variable in a CPU register, but it is not relevant
for any compiler used in the FreeBSD world today.

ANSIfy related prototypes while here.

Reviewed by:	cem, jhb
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D10193
2017-05-17 00:34:34 +00:00
Konstantin Belousov
396a0d4455 Do not wake up sleeping thread in reschedule_signals() if the signal
is blocked.  The spurious wakeup might result in spurious EINTR.

The reschedule_signals() function is called when the calling thread
has the signal mask changed.  For each newly blocked signal, we try to
find a thread which might have the signal not blocked.  If no such
thread exists, sigtd() returns random thread, which must not be waken
up.  I decided that re-checking, as suggested by PR submitter, is more
reasonable change than to change sigtd() interface, due to other uses
of sigtd().  signotify() already performs this check.

Submitted by:	Duane <parakleta@darkreality.org>
PR:	219228
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-05-12 15:34:59 +00:00
Mark Johnston
0c46712ca1 Let ptracestop() suspend threads sleeping in an SBDRY section.
When a thread enters ptracestop(), for example because it had received
SIGSTOP from ptrace(PT_ATTACH), it attempts to suspend other threads in
the same process. In the case of a thread sleeping interruptibly in an
SBDRY section, sig_suspend_threads() must wake the thread and allow it to
reach the user-mode boundary. However, sig_suspend_threads() would
erroneously avoid waking up such threads, resulting in an apparent hang.

Reviewed by:	kib
Tested by:	pho
MFC after:	2 weeks
Sponsored by:	Dell EMC Isilon
2017-05-11 17:03:45 +00:00
Brooks Davis
f19351aad8 Provide a freebsd32 implementation of sigqueue()
The previous misuse of sys_sigqueue() was sending random register or
stack garbage to 64-bit targets.  The freebsd32 implementation preserves
the sival_int member of value when signaling a 64-bit process.

Document the mixed ABI implementation of union sigval and the
incompability of sival_ptr with pointer integrity schemes.

Reviewed by:	kib, wblock
MFC after:	1 week
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D10605
2017-05-05 18:49:39 +00:00
Tycho Nightingale
86be94fca3 Add support for capturing 'struct ptrace_lwpinfo' for signals
resulting in a process dumping core in the corefile.

Also extend procstat to view select members of 'struct ptrace_lwpinfo'
from the contents of the note.

Sponsored by:	Dell EMC Isilon
2017-03-30 18:21:36 +00:00
Konstantin Belousov
469ec1eb6a When clearing altsigstack settings on exec, do it to the right thread.
Diagnosed by:	smh
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-03-17 13:37:37 +00:00
Eric Badger
b4d3325975 Don't clear p_ptevents on normal SIGKILL delivery
The ptrace() user has the option of discarding the signal. In such a
case, p_ptevents should not be modified. If the ptrace() user decides to
send a SIGKILL, ptevents will be cleared in ptracestop(). procfs events
do not have the capability to discard the signal, so continue to clear
the mask in that case.

Reviewed by:	jhb (initial revision)
MFC after:	1 week
Sponsored by:	Dell EMC
Differential Revision:	https://reviews.freebsd.org/D9939
2017-03-16 13:03:31 +00:00
Eric Badger
b38bd91f4f don't stop in issignal() if P_SINGLE_EXIT is set
Suppose a traced process is stopped in ptracestop() due to receipt of a
SIGSTOP signal, and is awaiting orders from the tracing process on how
to handle the signal. Before sending any such orders, the tracing
process exits. This should kill the traced process. But suppose a second
thread handles the SIGKILL and proceeds to exit1(), calling
thread_single(). The first thread will now awaken and will have a chance
to check once more if it should go to sleep due to the SIGSTOP.  It must
not sleep after P_SINGLE_EXIT has been set; this would prevent the
SIGKILL from taking effect, leaving a stopped orphan behind after the
tracing process dies.

Also add new tests for this condition.

Reviewed by:	kib
MFC after:	2 weeks
Sponsored by:	Dell EMC
Differential Revision:	https://reviews.freebsd.org/D9890
2017-03-07 13:41:01 +00:00
Ed Maste
e052a8b932 kern_sig.c: ANSIfy and remove archaic register keyword
Sponsored by:	The FreeBSD Foundation
2017-03-02 22:17:53 +00:00
Eric Badger
82a4538f31 Defer ptracestop() signals that cannot be delivered immediately
When a thread is stopped in ptracestop(), the ptrace(2) user may request
a signal be delivered upon resumption of the thread. Heretofore, those signals
were discarded unless ptracestop()'s caller was issignal(). Fix this by
modifying ptracestop() to queue up signals requested by the ptrace user that
will be delivered when possible. Take special care when the signal is SIGKILL
(usually generated from a PT_KILL request); no new stop events should be
triggered after a PT_KILL.

Add a number of tests for the new functionality. Several tests were authored
by jhb.

PR:		212607
Reviewed by:	kib
Approved by:	kib (mentor)
MFC after:	2 weeks
Sponsored by:	Dell EMC
In collaboration with:	jhb
Differential Revision:	https://reviews.freebsd.org/D9260
2017-02-20 15:53:16 +00:00