and current address space is already destroyed, so kern_execve()
terminates the process.
While there, clean up some internals of post_execve() inlined in init_main.
Reported by: Peter <pmc@citylink.dinoex.sub.org>
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D26525
This makes it possible to run an unmodified Linux syzkaller executor
against the Linuxulator, and have it gather code coverage information.
Sponsored by: The FreeBSD Foundation
This is a step towards facilitating jails with only Linux binaries.
Supporting emul_path adds path lookups which are completely spurious
if the binary at hand runs in a Linux-based root directory.
It defaults to on (== current behavior).
make -C /root/linux-5.3-rc8 -s -j 1 bzImage:
use_emul_path=1: 101.65s user 68.68s system 100% cpu 2:49.62 total
use_emul_path=0: 101.41s user 64.32s system 100% cpu 2:45.02 total
After r340674, the "continue" would restart the loop without having
updated clen, resulting in an infinite loop. Restore the old behaviour
of simply ignoring all control messages on such sockets, since we
currently only implement handling for AF_UNIX-specific messages.
Reported by: syzkaller
Reviewed by: tijl
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D26093
vm_object_madvise() is a no-op for unmanaged objects, but we should also
limit the scope of mappings on which pmap_remove() is called. In
particular, with the WIP largepage shm objects patch the kernel must
remove mappings of such objects along superpage boundaries, and without
this check Linux madvise(MADV_DONTNEED) could violate that requirement.
Reviewed by: alc, kib
MFC with: r362631
Sponsored by: Juniper Networks, Klara Inc.
Differential Revision: https://reviews.freebsd.org/D26084
It is documented as a raw hardware-based clock not subject to NTP or
incremental adjustments. With this "not as precise as CLOCK_MONOTONIC"
description in mind, map it to our CLOCK_MONOTNIC_FAST (the same
mapping as for the linux CLOCK_MONOTONIC_COARSE).
This is needed for the webcomponent of steam (chromium) and some
other steam component or game.
The linux-steam-utils port contains a LD_PRELOAD based fix for this.
There this is mapped to CLOCK_MONOTONIC.
As an untrained ear/eye (= the majority of people) is normaly not
noticing a difference of jitter in the 10-20 ms range, specially
if you don't pay attention like for example in a browser session
while watching a video stream, the mapping to CLOCK_MONOTONIC_FAST
seems more appropriate than to CLOCK_MONOTONIC.
The reason for this is to work around an idiosyncrasy of glibc
getttynam(3) implementation: it checks whether st_dev returned for
fd 0 is the same as st_dev returned for the target of /proc/self/fd/0
symlink, and with linux chroots having their own devfs instance,
the check will fail if you chrooted into it.
PR: kern/240767
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25559
memfd_create fds will no longer require an ftruncate(2) to set the size;
they'll grow (to the extent that it's possible) upon write(2)-like syscalls.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D25502
it would fail with EINVAL, breaking some of the Python regression
tests.
While here, cap the user-controlled message length.
Note that the code doesn't seem to be copying out the new length
in either (success or failure) case. This will be addressed separately.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25392
TCGETS et al are frequently issued by Linux binaries while the previous code
avoidably ping-pongs a global sx lock and serializes on Giant.
Note that even with the fix the common case will serialize on a per-tty lock.
and fixes a bug where calling accept(2) could result in closing fd 0.
Note that the code still contains a number of problems: it makes
assumptions about l_sockaddr_in being the same as sockaddr_in,
the EFAULT-related code looks like it doesn't work at all, and the
socket type check is racy. Those will be addressed later on;
I'm trying to work in small steps to avoid breaking one thing while
fixing another.
It fixes Redis, among other things.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25461
rpokala notes that splitting the definitions like this is kind of silly,
since the comment applies to both. Move the comment up (or the definition
down, depending on your perspective on life) accordingly.
Reported by: rpokala
This effectively mirrors our libc implementation, but with minor fudging --
name needs to be copied in from userspace, so we just copy it straight into
stack-allocated memfd_name into the correct position rather than allocating
memory that needs to be cleaned up.
The sealing-related fcntl(2) commands, F_GET_SEALS and F_ADD_SEALS, have
also been implemented now that we support them.
Note that this implementation is still not quite at feature parity w.r.t.
the actual Linux version; some caveats, from my foggy memory:
- Need to implement SHM_GROW_ON_WRITE, default for memfd (in progress)
- LTP wants the memfd name exposed to fdescfs
- Linux allows open() of an fdescfs fd with O_TRUNC to truncate after dup.
(?)
Interested parties can install and run LTP from ports (devel/linux-ltp) to
confirm any fixes.
PR: 240874
Reviewed by: kib, trasz
Differential Revision: https://reviews.freebsd.org/D21845
with python3.8 from Focal triggers those.
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25491
Linux MADV_DONTNEED is not advisory: it has side effects for anonymous
memory, and some system software depends on that. In particular,
MADV_DONTNEED causes anonymous pages to be discarded. If the mapping is
a private mapping of a named object then subsequent faults are to
repopulate the range from that object, otherwise pages will be
zero-filled. For mappings of non-anonymous objects, Linux MADV_DONTNEED
can be implemented in the same way as our MADV_DONTNEED.
This implementation differs from Linux semantics in its handling of
private mappings, inherited through fork(), of non-anonymous objects.
After applying MADV_DONTNEED, subsequent faults will repopulate the
mapping from the parent object rather than the root of the shadow chain.
PR: 230160
Reviewed by: alc, kib
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D25330
FreeBSD madvise(2) directly. While some of the flag values match,
most don't.
PR: kern/230160
Reported by: markj
Reviewed by: markj
Discussed with: brooks, kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25272
If multithreaded non-Linux process execs Linux binary, then non-Linux
threads different from the one that execing are cleared by
single-threading at boundary, and then terminating them in
post_execve(). Since at that time the process is already switched to
linux ABI, linuxolator is involved in the thread clearing on boundary,
but cannot find the emul data.
Handle it by pre-creating emuldata for all threads in the execing process.
Also remove a code in linux_proc_exec() handler that cleared emul data
for other threads when execing from multithreaded Linux process. It is
excessive.
PR: 247020
Reported by: Martin FIlla <freebsd@sysctl.cz>
Reported by: Henrique L. Amorim, Independent Security Researcher
Reported by: Rodrigo Rubira Branco (BSDaemon), Amazon Web Services
Reviewed by: markj
Tested by: trasz
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D25293
PR: kern/240432
Analyzed by by: Alex S <iwtcex@gmail.com>
Reviewed by: emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25248
the debug messages. While here, clean up some variable naming.
Reviewed by: bcr (manpages), emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25230
- Use the same definition of free memory as Linux.
- Rename the totalbig and freebig fields to match the corresponding
names on Linux.
Discussed with: alc
MFC after: 1 week
applications, which often depend on this being the case. There's a new
sysctl, compat.linux.default_openfiles, to control this behaviour.
Reviewed by: kevans, emaste, bcr (manpages)
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25177
standard SO_SNDBUF/SO_RCVBUF. Mostly cosmetics, to get rid
of the warning during 'apt upgrade'.
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25173
The previous code was computing an incorrect value in a very expensive
manner. "sharedram" is supposed to be the amount of memory used by
named swap objects, which on FreeBSD basically corresponds to memory
usage by shared memory objects (including, for example, GEM objects) and
tmpfs. We currently have no cheap way to count such pages. The
previous code tried to determine the number of copy-on-write pages
shared between processes.
Just replace the computed value with 0. illumos reportedly does the
same thing. Linux itself did not populate this field until a 2014
commit, "mm: export NR_SHMEM via sysinfo(2) / si_meminfo() interfaces".
Reported by: mjg
MFC after: 1 week
Copy the CP, PTRIN, etc macros from freebsd32.h into a sys/abi_compat.h
and replace existing definitation with includes where required. This
eliminates duplicate code and allows Linux and FreeBSD compatability
headers to be included in the same files.
Input from: cem, jhb
Obtained from: CheriBSD
MFC after: 2 weeks
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24275
