memfd_create is effectively a SHM_ANON shm_open(2) mapping with optional
CLOEXEC and file sealing support. This is used by some mesa parts, some
linux libs, and qemu can also take advantage of it and uses the sealing to
prevent resizing the region.
This reimplements shm_open in terms of shm_open2(2) at the same time.
shm_open(2) will be moved to COMPAT12 shortly.
Reviewed by: markj, kib
Differential Revision: https://reviews.freebsd.org/D21393
machine/regnum.h ends up being included by sys/procfs.h and sys/ptrace.h via
machine/reg.h. Many of the regnum definitions are too short and too generic
to be exposing to any userland application including one of these two
headers. Moreover, these actively cause build failures in googletest
(template <typename T1 ...> expanding to template <typename 9 ...>).
Hide the definitions behind _KERNEL or _WANT_MIPS_REGNUM, and patch all of
the userland consumers to define as needed.
Discussed with: imp, jhb
Reviewed by: imp, jhb
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21330
Inform D that C executed procctl(PROC_PDEATHSIG_CTL). Otherwise D
might allow B to exit before C is set up to receive a signal on the
parent exit. In this case, C waits forever for the signal and test
hangs.
PR: 237657
Reported and tested by: lwhsu
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
ptrace(PT_DETACH) requires stopped debuggee, otherwise it fails. When
the call fails, the C process is left as debuggee of the process D,
and might be killed too early if process D exits occurs fast enough.
Since pipes are not closed in the forked children, this resulted in
the test hanging, since no write occured from C to wake A.
PR: 237657
Reported and tested by: lwhsu
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
The process is reparented to the debugger while it is attached.
B B
/ ----> |
A A D
Every time when the process is reparented, it is added to the orphan list
of the previous parent:
A->orphan = B
D->orphan = NULL
When the A process will close the process descriptor to the B process,
the B process will be reparented to the init process.
B B - init
| ---->
A D A D
A->orphan = B
D->orphan = B
In this scenario, the B process is in the orphan list of A and D.
When the last process descriptor is closed instead of reparenting
it to the reaper let it stay with the debugger process and set
our previews parent to the reaper.
Add test case for this situation.
Notice that without this patch the kernel will crash with this test case:
panic: orphan 0xfffff8000e990530 of 0xfffff8000e990000 has unexpected oppid 1
Reviewed by: markj, kib
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D20361
This ptrace operation returns a structure containing the error and
return values from the current system call. It is only valid when a
thread is stopped during a system call exit (PL_FLAG_SCX is set).
The sr_error member holds the error value from the system call. Note
that this error value is the native FreeBSD error value that has _not_
been translated to an ABI-specific error value similar to the values
logged to ktrace.
If sr_error is zero, then the return values of the system call will be
set in sr_retval[0] and sr_retval[1].
Reviewed by: kib
MFC after: 1 month
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D20901
rename the source to gsb_crc32.c.
This is a prerequisite of unifying kernel zlib instances.
PR: 229763
Submitted by: Yoshihiro Ota <ota at j.email.ne.jp>
Differential Revision: https://reviews.freebsd.org/D20193
The zero-padding when printing out the Size field is on 32-bit architectures is
5, not 15. Adjust the regular expression to work with both the 32-bit and
64-bit case.
MFC after: 1 week
Reviewed by: lwhsu, markj
Approved by: emaste (mentor, implicit)
Differential Revision: https://reviews.freebsd.org/D20005
Such processes will be reparented to the reaper when the current
parent is done with them (i.e., ptrace detached), so p_oppid must be
updated accordingly.
Add a regression test to exercise this code path. Previously it
would not be possible to reap an orphan with a stale oppid.
Reviewed by: kib, mjg
Tested by: pho
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19825
When building with KCOV enabled the compiler will insert function calls
to probes allowing us to trace the execution of the kernel from userspace.
These probes are on function entry (trace-pc) and on comparison operations
(trace-cmp).
Userspace can enable the use of these probes on a single kernel thread with
an ioctl interface. It can allocate space for the probe with KIOSETBUFSIZE,
then mmap the allocated buffer and enable tracing with KIOENABLE, with the
trace mode being passed in as the int argument. When complete KIODISABLE
is used to disable tracing.
The first item in the buffer is the number of trace event that have
happened. Userspace can write 0 to this to reset the tracing, and is
expected to do so on first use.
The format of the buffer depends on the trace mode. When in PC tracing just
the return address of the probe is stored. Under comparison tracing the
comparison type, the two arguments, and the return address are traced. The
former method uses on entry per trace event, while the later uses 4. As
such they are incompatible so only a single mode may be enabled.
KCOV is expected to help fuzzing the kernel, and while in development has
already found a number of issues. It is required for the syzkaller system
call fuzzer [1]. Other kernel fuzzers could also make use of it, either
with the current interface, or by extending it with new modes.
A man page is currently being worked on and is expected to be committed
soon, however having the code in the kernel now is useful for other
developers to use.
[1] https://github.com/google/syzkaller
Submitted by: Mitchell Horne <mhorne063@gmail.com> (Earlier version)
Reviewed by: kib
Testing by: tuexen
Sponsored by: DARPA, AFRL
Sponsored by: The FreeBSD Foundation (Mitchell Horne)
Differential Revision: https://reviews.freebsd.org/D14599
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
Fix reporting of SS_ONSTACK in nested signal delivery when sigaltstack()
is used on some architectures.
Add a unit test for this. I tested the test by introducing the bug
on amd64. I did not test it on other architectures.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D18347
Unconditionally reparenting to PID 1 breaks the procctl(2) reaper
functionality.
Add a regression test for this case.
Reviewed by: kib
Approved by: re (gjb)
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17589
FreeBSD's mkstemp sets the temporary file's permissions to 600, and has ever
since mkstemp was added in 1987. Coverity's warning is still relevant for
portable programs since OpenGroup does not require that behavior, and POSIX
didn't until 2008. But none of these programs are portable.
umask(2) should always be used prior to mkstemp(3) so the temporary file
won't be created with insecure permissions.
Reported by: Coverity
CID: 1331605 1347173 1375366 1339800 1331604 1296056 1296060
CID: 1296057 1296062
MFC after: 2 weeks
- Add some more cases to the truncation test.
- Remove the "expect fail" annotations.
PR: 131876
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D16562
With r337328, the test hangs becase the sendmsg() call will block until
the receive buffer is at least partially drained. Fix the problem by
using a non-blocking socket and allowing short writes. Also assert
that a SCM_CREDS message was received if one was expected.
PR: 181741
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D16516
Enable the LOCAL_PEERCRED socket option for unix domain stream sockets
created with socketpair(2). Previously, it only worked with unix domain
stream sockets created with socket(2)/listen(2)/connect(2)/accept(2).
PR: 176419
Reported by: Nicholas Wilson <nicholas@nicholaswilson.me.uk>
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D16350
- Remove return statements in functions with a void return type.
- Allocate enough space for the SCM_CREDS and SCM_RIGHTS messages
received in the rights_creds_payload test.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
If an error occurs while copying a SCM_RIGHTS message to userspace,
we free the mbuf containing externalized rights, leaking them.
PR: 131876
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
A pipe was was left over from a development version of pdeathsig.c and
is not needed.
Process C waits for a signal that'll be generated when process B
exists. Process B waits for process D to send it a byte via pipe_db
before it exits. Process D sends the byte after it has started
ptrace()ing process C. The point of the test is to show that process C
receives the signal because process B exited, even though C has been
reparented to process D. The pipe pipe_cd isn't doing anything useful
(though in an earlier version of the patch it did). Clean that up by
removing the useless pipe.
Submitted by: Thomas Munro
MFC after: 6 days
Differential revision: https://reviews.freebsd.org/D15214
- ptrace__breakpoint_siginfo tests that a SIGTRAP for a software breakpoint
in userland triggers a SIGTRAP with a signal code of TRAP_BRKPT.
- ptrace__step_siginfo tests that a SIGTRAP reported for a step after
stepping via PT_STEP or PT_SETSTEP has a signal code of TRAP_TRACE.
- Use a single list of platforms to define HAVE_BREAKPOINT for platforms
that expose a functional breakpoint() inline to userland. Replace
existing lists of platform tests with HAVE_BREAKPOINT instead.
- Add support for advancing PC past a breakpoint inserted via breakpoint()
to support the existing ptrace__PT_CONTINUE_different_thread test on
non-x86 platforms (x86 advances the PC past the breakpoint instruction,
but other platforms do not). This is implemented by defining a new
SKIP_BREAK macro which accepts a pointer to a 'struct reg' as its sole
argument and modifies the contents to advance the PC. The intention is
to use it in between PT_GETREGS and PT_SETREGS.
Tested on: amd64, i386, mips (after adding a breakpoint() to mips)
MFC after: 1 month
-> PROC_PDEATHSIG_STATUS for consistency with other procctl(2)
operations names.
Requested by: emaste
Sponsored by: The FreeBSD Foundation
MFC after: 13 days
Allow processes to request the delivery of a signal upon death of
their parent process. Supposed consumer of the feature is PostgreSQL.
Submitted by: Thomas Munro
Reviewed by: jilles, mjg
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D15106
