Merge pull request #568 from mihalicyn/cg_proc_stat_use_after_free

[RFC] cpuview: fix possible use-after-free in find_proc_stat_node

cpuview: fix possible use-after-free in find_proc_stat_node

Our current lock design uses 2 sync primitives.
First (pthread_rwlock) protects hash table buckets.
Second (pthread_mutex) protects each struct cg_proc_stat
from concurrent modification. But the problem is that function
find_proc_stat_node() can return a pointer to the node
(struct cg_proc_stat) which can be freed by prune_proc_stat_history()
call *before* we take pthread_mutex. Moreover, we perform
memory release of (struct cg_proc_stat) in prune_proc_stat_list()
without any protection like refcounter or mutex on (struct cg_proc_stat).

An attempt to guess what happens in:
https://github.com/lxc/lxcfs/issues/565
https://discuss.linuxcontainers.org/t/number-of-cpus-reported-by-proc-stat-fluctuates-causing-issues/15780/14

Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>

Merge pull request #567 from mihalicyn/cpuinfo_with_personality

cpuinfo with personality

cpuview: paththrough personality when reading cpuinfo

Let's change processing thread personality if caller personality
is different. It allows to read /proc/cpuinfo properly in
some cases (arm64 rely on current->personality inside Linux kernel).

https://github.com/lxc/lxcfs/issues/553

Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>

utils: add get_task_personality helper

Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>

macro.h: add strnprintf macro

Stolen from LXC

Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>

utils: add safe_uint32() helper

Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>

Merge pull request #564 from blue-troy/master

doc: guide for mount /sys/devices/system/cpu in docker demo

doc: guide for mount /sys/devices/system/cpu in docker demo

Signed-off-by: blue-troy <12729455+blue-troy@users.noreply.github.com>

Merge pull request #563 from gibmat/fix-ia64-build

Fix build on ia64

Fix build on ia64

The relevant code was added in commit 35acc24, but the function/macro
prctl_arg() didn't seem to be defined anywhere in the repo. lxc
currently has a corresponding macro defined in src/lxc/macro.h that
casts the value to an unsigned long. But 0 doesn't require any special
handling, so remove the call to prctl_arg().

Verified that the code compiles properly on Debian's ia64 porterbox
(yttrium).

Signed-off-by: Mathias Gibbens <gibmat@debian.org>

Merge pull request #552 from bytedance/set-oom-score-adj

set oom_score_adj of lxcfs process to -1000

set oom_score_adj of lxcfs process to -1000

Disable oom killing entirely to minimize the hassle comes from
lxcfs exiting unexpectedly, e.g. the mountpoint got lost.

Signed-off-by: Teng Hu <huteng.ht@bytedance.com>

Merge pull request #550 from Blub/bindings-reinit-fuse3-fixup

fix reinitialization with fuse3

fix reinitialization with fuse3

With fuse3 `fuse_get_context` returns NULL before fuse was
fully initialized, so we must not access it.

Futher, we call 'do_reload' for normal initialization as
well, so let's prevent that from re-initializing the
bindings initially and only do this on actual reloads,
otherwise we do it twice on startup.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Fixes #549

Merge pull request #545 from Blub/init-lib-at-reload-drop-fuse-init-return

re-initialize library after reload

Merge pull request #547 from stgraber/master

Complete Github Actions migration

github: Validate target branch

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

github: Restrict permissions

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #546 from Blub/sys-cpu-cpu-readdir

replace opathdir with opendir_flags

replace opathdir with opendir_flags

`opathdir` was used to replace `opendir` in order to ensure
`O_NOFOLLOW` and `O_CLOEXEC` were set, however it also added
`O_PATH` which prevents `readdir`/`getdents` to be used on
it, causing the `/sys/devices/system/cpu/<subdir>`
directories to be empty.

Instead, let's have an `opendir_flags` utility which simply
passed additional flags to the `open(..., O_DIRECTORY)` call
preceding `fdopendir()`.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

re-initialize library after reload

When introducing versioned options, we started using fuse's
"init" callback in order to tell the library to set
`can_use_sys_cpu` and `has_versioned_opts` accordingly.

However, we forgot to also do this on a reload. Fix this by
simply calling `lxcfs_fuse_init()` in `do_reload()` as well.

Additionaly: ignore lxcfs_fuse_init()'s return value.
We just "passed through" the private_data from fuse which is
set via the `fuse_main()` call.

It's better to not leave this up to the library anyway in
order to make it easier to be fuse version agnostic in the
future.

Without this, issuing a reload to lxcfs would cause
files in `/sys/devices/system/cpu/` to be visible via
`readdir`, but accessing them would fail:

    ~ # ls /sys/devices/system/cpu/
    ls: /sys/devices/system/cpu/cpuidle: No such file or directory
    ls: /sys/devices/system/cpu/uevent: No such file or directory
    (...)

    ~ # echo /sys/devices/system/cpu/*
    /sys/devices/system/cpu/cpu0 /sys/devices/system/cpu/cpu1 (...)

    ~ # strace stat /sys/devices/system/cpu/cpu0
    lstat("/sys/devices/system/cpu/cpu0", 0x7ffdb2c57a00) = -1 ENOENT (No such file or directory)

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

Merge pull request #544 from mchtech/cgoup-v2-cpu-count

cgroup v2: /sys/devices/system/cpu/online returns zero

cgroup v2: return cpuset cpu count when no quota is set

Signed-off-by: michuan <michu_an@126.com>

Merge pull request #541 from bytedance/cleanup-getsize

sysfs: cleanup sys_devices_system_cpu_online_getsize

sysfs: cleanup sys_devices_system_cpu_online_getsize

cleanup useless parameters and local variables, meanwhile,
a compiler warning resolved.

Signed-off-by: huteng.ht <huteng.ht@bytedance.com>

Merge pull request #539 from bytedance/calc-online-file-size

sysfs: correct file size of /sys/devices/system/cpu/online.

sysfs: correct file size of /sys/devices/system/cpu/online.

Calculate accurate size of 'online' file in sys_getattr routine.

Signed-off-by: huteng.ht <huteng.ht@bytedance.com>

Merge pull request #537 from dasteihn/sta/commentfix

util: remove doubled comment

util: remove doubled comment

Signed-off-by: Philipp Stanner <stanner@posteo.de>

Merge pull request #536 from yrhki/extra-space

proc_fuse: extra space in /proc/stat

proc_fuse: extra space in /proc/stat

Signed-off-by: Tuomas Yrjölä <mail@yrhki.fi>

Merge pull request #535 from stgraber/master

meson: Syntax nit

meson: Syntax nit

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #533 from stgraber/master

Meson tweaks for init systems

meson: Support multiple init systems

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

init: Fix install paths for sysvinit and openrc

Closes #532

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #531 from stgraber/master

Fix tests

tests: Skip sysfs test on older FUSE versions

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

github: Re-organize Github Actions

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #530 from Blub/2022-01-17/optional-fuse-2

support explicit fuse version choice

support explicit fuse version choice

We'd like to provide an easy upgrade path which doesn't
cause an lxcfs-reload to crash because the new library was
built against the wrong version.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

Merge pull request #526 from brauner/2022-03-13.fixes

sysfs_fuse: fixes

Merge pull request #528 from thmo/unitdir

Query systemd system unit dir.

Query systemd system unit dir.

Signed-off-by: Thomas Moschny <thomas.moschny@gmx.de>

Merge pull request #527 from Foxboron/morten/fix-libdir

init/meson: Use libdir instead of hardcoded /lib path

init/meson: Use libdir instead of hardcoded /lib path

Hardcoding `/lib` makes meson create a directory which would conflict on
distros with usrmerge as `/lib` is a symlink. We define `libdir` in the
top-level so we should be using that instead.

Signed-off-by: Morten Linderud <morten@linderud.pw>

meson: handle fuse versions with buggy dt_type handling

Link: https://github.com/libfuse/libfuse/pull/591
Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

github: add fuse3 tests

Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

meson: bump fuse version

Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

sysfs_fuse: generate file info for cpu<nr> entries as well

Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

sysfs_fuse: fix indendation

Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

utils: add and use opathdir()

Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

Merge pull request #525 from stgraber/master

More sysfs fixes

tests: Fix sysfs test

For the sysfs test to be useful, we need /sys/devices/system/cpu/ to
actually be mounted.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

sysfs: Don't incorrectly filter entries

The filtering logic was completely skipping any entry which was 3
characters or shorter. Instead change the logic to only attempt to parse
those entries longer than 3 characters.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #524 from Foxboron/morten/docs

meson: Include documentation

Merge pull request #523 from brauner/2022-03-12.fixes

fuse: set file info for fuse2

workflows: disable documentation generation

Signed-off-by: Morten Linderud <morten@linderud.pw>

meson: Include documentation

Documentation was removed from the build system with the migration to
meson. This implements the help2man generation which existed in the
autoconf setup.

Signed-off-by: Morten Linderud <morten@linderud.pw>

tests: add test for issue #522

Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

tree-wide: ensure that file information is set even with legacy fuse

Fixes: #522
Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

tree-wide: remove struct stat argument from DIR_FILLER and make it static inline

Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

lxcfs_fuse: ensure lxcfs_fuse_compat.h is included after including fuse header

Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

Release LXCFS 5.0.0

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #521 from stgraber/master

Makefile: Fix ordering and add PHONY

Makefile: Fix ordering and add PHONY

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #520 from stgraber/master

More meson tweaks

Makefile: Tweak for meson (add dist target)

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

meson: Set check argument on run_command

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #519 from stgraber/master

meson: Cleanup build files

meson: Cleanup build files

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

Merge pull request #518 from brauner/2022-03-07.fixes

proc_fuse: improve error message

proc_fuse: improve error message

Fixes: #516
Signed-off-by: Christian Brauner (Microsoft) <christian.brauner@ubuntu.com>

Merge pull request #515 from phanhuy1502/preserve-cpu-sum-when-cpu-set-changes

Preseve cpu sum in /proc/stat when cpuset changes

Preseve cpu sum in /proc/stat when cpuset changes

Signed-off-by: Nguyen Phan Huy <phanhuy1502@gmail.com>

Merge pull request #514 from Blub/2022-01-17/fix-and-reformat-format-strings

fix and reformat format strings

fix and reformat format strings

Some of these missed the spaces in between and in order to
make this more readable and apparent, put one field per line
and add comments matching the field names.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

Merge pull request #509 from brauner/2021-12-13.fixes

tree-wide: use PRIu64 to print uint64_t

proc_loadavg: use PRIu64 to print uint64_t

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

proc_fuse: use PRIu64 to print uint64_t

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

proc_cpuview: use PRIu64 to print uint64_t

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

proc_fuse: use correct type for swap variables

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

build: move global options further up

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #508 from Blub/2021-12-09/cgv2-swap-meminfo

make meminfo and swaps cgroupv2 aware

make meminfo and swaps cgroupv2 aware

and deduplicate the corresponding code

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

Merge pull request #506 from Sn0rt/empty-cgroup-if-set-unified_cgroup_hierarchy=1

empty cgroup dir if set unified_cgroup_hierarchy=1

empty cgroup dir if set unified_cgroup_hierarchy=1

Signed-off-by: Guohao Wang <wangguohao.2009@gmail.com>

Merge pull request #501 from phanhuy1502/detect-disable-cfs-quota

Skip cpu revise when cfs quota is disable

Skip cpu revise when cfs quota is disable

Signed-off-by: Nguyen Phan Huy <phanhuy1502@gmail.com>

Merge pull request #499 from brauner/2021-11-05.fixes

build: fixes

build: use jinja2 templating

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

build: add LXCFSTARGETDIR to configuration data

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #496 from Foxboron/morten/fix-src

meson: Include lxcfs_fuse.h into source files

meson: Include lxcfs_fuse.h into source files

Signed-off-by: Morten Linderud <morten@linderud.pw>

Merge pull request #495 from brauner/2021-10-20.fixes

build: fixes

github/workflows: meson compile -C build everywhere

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

build: add share/ directory

This was somehow missing until now.

Fixes: #494
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

build: remove newline

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #493 from brauner/2021-10-19.fixes.2

sysfs: fix cpumasks