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
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
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
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
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
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
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
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
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
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
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
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
- 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
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
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
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
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
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.
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
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
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
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
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
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
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
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
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
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
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
Use C99 designators to set the value of each slot and the nitems macro to
check for valid entries. In the process, switch to indexing by signal
number rather than signal-1 for improved clarity.
Obtained from: CheriBSD (a6053c5abf03a5f53bbfcdd3a26429383f67e09f)
Sponsored by: DARPA, AFRL
Reviewed by: kib
target. Due to a way issignal() selects the next signal to deliver
and report, if the simultaneous or already pending another signal
exists, that signal might be reported by the next waitpid(2) call.
This causes minor annoyance for debuggers, which must be prepared to
take any signal as the first event, then filter SIGSTOP later.
More importantly, for tools like gcore(1), which attach and then
detach without processing events, SIGSTOP might leak to be delivered
after PT_DETACH. This results in the process being unintentionally
stopped after detach, which is fatal for automatic tools.
The solution is to force SIGSTOP to be the first signal reported after
the attach. Attach code is modified to set P2_PTRACE_FSTP to indicate
that the attaching ritual was not yet finished, and issignal() prefers
SIGSTOP in that condition. Also, the thread which handles
P2_PTRACE_FSTP is made to guarantee to own p_xthread during the first
waitpid(2). All that ensures that SIGSTOP is consumed first.
Additionally, if P2_PTRACE_FSTP is still set on detach, which means
that waitpid(2) was not called at all, SIGSTOP is removed from the
queue, ensuring that the process is resumed on detach.
In issignal(), when acting on STOPing signals, remove the signal from
queue before suspending. Otherwise parallel attach could result in
ptracestop() acting on that STOP as if it was the STOP signal from the
attach. Then SIGSTOP from attach leaks again.
As a minor refactoring, some bits of the common attach code is moved
to new helper proc_set_traced().
Reported by: markj
Reviewed by: jhb, markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D7256
number of core files allowed by a particular process when using the %I core
file name pattern.
Sanity check at compile time to ensure the value is within the valid range of
0-10.
Reviewed by: jtl, sjg
Approved by: sjg (mentor)
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D6812
