conf: improve idmapped mounts support

Setting up a detached idmapped mount is a privileged operation, mounting
it doesn't have to be.

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

conf: s/lxc_rootfs_prepare/lxc_rootfs_init/g

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

conf: move all mount options into struct lxc_mount_options

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

conf: stash lxc_storage into lxc_rootfs and bind to its lifetime

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

Merge pull request #3810 from brauner/2021-04-24.fixes

configure: fix function detection

configure: fix function detection

Fixes: #3809
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #3808 from brauner/2021-04-23.fixes

dir: fix rootfs mounting

dir: fix rootfs mounting

We need to be able to lookup symlinks and allow xdev.

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

Merge pull request #3807 from evverx/seccom-leak

seccomp: init and destroy notifier.cookie

Merge pull request #3805 from brauner/2021-04-22.fixes.3

mntopt fixes

conf: don't overrun dest buffer in parse_lxc_mntopts()

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

conf: better naming

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

Merge pull request #3804 from brauner/2021-04-22.fixes.2

getsubopt: use correct include

getsubopt: use correct include

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

Merge pull request #3803 from brauner/2021-04-22.fixes

include fixes for Bionic

Makefile: fix strchrnul() inclusion

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

conf: include strchrnul for platforms that don't support it

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

strchrnul: include header

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

Merge pull request #3709 from brauner/2021-03-17/idmapped_mounts_v2

Initial support for idmapped mounts

conf: don't allow idmapped lxc.mount.{entry,fstab} just yet

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

conf: tweak parse_lxc_mntopts()

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

apparmor:  handle on-exec

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

attach: use correct lxc_namespace_t type

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

attach: visually separate pids from fds during initalization

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

conf: verify that the rootfs can support idmapped mounts

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

start: documented idmapped mounts

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

mount_utils: add two detached mount helpers

They'll come in handy in the future.

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

conf: support idmapping directories

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

mount_utils: add helper to determine whether new mount api supports bind mounts

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

storage: keep a reference to lxc_rootfs in lxc_storage

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

mount_utils: add support for mount_setattr() syscall

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

confile: parse idmap=<path> mount option for rootfs

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

conf: add first, trivial support for idmapped mounts

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

conf: rework lxc specific mount option parsing

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

Merge pull request #3801 from evverx/san-tweaks

ci: make use of --enable-sanitizers instead of CFLAGS

Merge pull request #3800 from evverx/gh3796

Revert "ci: get around https://github.com/lxc/lxc/issues/3796"

Merge pull request #3787 from evverx/san-build

ci: an attempt to run the tests under ASan/UBsan

Merge pull request #3799 from evverx/apparmor-bytes

apparmor: turn bytes into null-terminated strings before calling strcspn

Merge pull request #3790 from brauner/2021-04-15.fixes

lxc_clone & configure fix

commands: don't needlessly allocate

Fixes: #3796
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #3797 from evverx/pass-on-asan

tests: pass on ASAN/UBSAN options to several tests

process_utils: free stack after return

Fixes: #3789
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

configure: fix sanitizer compilation

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

error_utils: add missing macro.h include

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

Merge pull request #3794 from evverx/gh3791

tests: stop cutting off right square brackets in share_ns

Merge pull request #3793 from evverx/busybox-test

tests: switch to the "busybox" template in lxc-test-checkpoint-restore

seccomp: init and destroy notifier.cookie

It's a follow-up to 84cf6d259b24e4ad48e

Closes https://github.com/lxc/lxc/issues/3806

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

Merge pull request #3785 from brauner/2021-04-14.fixes

lxccontainer: fix container creation error paths

Merge pull request #3784 from evverx/attach-memleak

tests: fix a memory leak in attach

lxccontainer: fix container creation error paths

Fixes: #3782
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

autoconf: stop passing -fsanitize=address via AM_LDFLAGS

The snippet is redundant because the build system automatically
passes the sanitizers flags set in AM_CFLAGS to the linker

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: get rid of the -static-libasan stopgap

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

build-system: stop building init.lxc.static with sanitizers

`-static` isn't compatible with `-fsanitize=`:
```
gcc: error: cannot specify -static with -fsanitize=address
```

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

autoconf: add AC_LANG_SOURCE to CC_CHECK_LDFLAGS

Inspired by https://lore.kernel.org/alsa-devel/18135209-abc9-ca1c-84e0-8ac3e75caaf1@perex.cz/t/

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

Merge pull request #3783 from evverx/cgpath-memleak2

tests: fix a memory leak in cgpath

ci: make use of --enable-sanitizers instead of CFLAGS

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

Merge pull request #3781 from evverx/lxcpath-memleak

tests: fix a memory leak in lxcpath

Merge pull request #3780 from evverx/cgpath-mem-leak

tests: fix a memory leak in cgpath

tests: free the buffer filled by lxc_cmd_rsp_recv

Fixes https://github.com/lxc/lxc/issues/3796

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

Revert "ci: get around https://github.com/lxc/lxc/issues/3796"

This reverts commit 44818e893e68e6e76652323ff4f12c9214d2ffa7.

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: build with -Wall -Werror

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: turn on strict_string_checks

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: get around https://github.com/lxc/lxc/issues/3796

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: prevent lxc-exercise from running indefinitely

and show all the commands it runs to make it easier to
debug potential issues.

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: get around https://github.com/lxc/lxc/issues/3788

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: get around https://github.com/lxc/lxc/issues/3798

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: switch to lxc-exercise from the lxc-ci repository

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: link lib[au]san with init.lxc.static statically

init.lxc.static is run in arbitrary containers where the libasan library lxc has been built with
isn't always installed. To make it work let's override GCC's default and link both libasan
and libubsan statically. It should help to fix issues like
```
++ lxc-execute -n c1 -- sudo -u ubuntu /nnptest
lxc-init: error while loading shared libraries: libasan.so.5: cannot open shared object file: No such file or directory
```

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: an attempt to run the tests under ASan/UBsan

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

apparmor: turn bytes into null-terminated strings before calling strcspn

```
==70349==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6020000009fb at pc 0x000000433b70 bp 0x7ffcde087810 sp 0x7ffcde086fd0
READ of size 12 at 0x6020000009fb thread T0
    #0 0x433b6f in strcspn (/usr/bin/lxc-execute+0x433b6f)
    #1 0x7f720413a5cb in apparmor_process_label_get /home/runner/work/lxc/lxc/src/lxc/lsm/apparmor.c:449:8
    #2 0x7f720413bc2a in apparmor_prepare /home/runner/work/lxc/lxc/src/lxc/lsm/apparmor.c:1104:13
    #3 0x7f720409b6e9 in lxc_init /home/runner/work/lxc/lxc/src/lxc/start.c:848:8
    #4 0x7f72040a395a in __lxc_start /home/runner/work/lxc/lxc/src/lxc/start.c:2009:8
    #5 0x7f7203fc7186 in lxc_execute /home/runner/work/lxc/lxc/src/lxc/execute.c:99:9
    #6 0x7f7204000e44 in do_lxcapi_start /home/runner/work/lxc/lxc/src/lxc/lxccontainer.c:1112:9
    #7 0x7f7203ff0c07 in lxcapi_start /home/runner/work/lxc/lxc/src/lxc/lxccontainer.c:1149:8
    #8 0x4c6912 in main /home/runner/work/lxc/lxc/src/lxc/tools/lxc_execute.c:224:9
    #9 0x7f72034ac0b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
    #10 0x41d93d in _start (/usr/bin/lxc-execute+0x41d93d)
+ echo ---

0x6020000009fb is located 0 bytes to the right of 11-byte region [0x6020000009f0,0x6020000009fb)
allocated by thread T0 here:
    #0 0x496399 in realloc (/usr/bin/lxc-execute+0x496399)
    #1 0x7f7203fcf85c in fd_to_buf /home/runner/work/lxc/lxc/src/lxc/file_utils.c:463:10
    #2 0x7f720413a52b in apparmor_process_label_get /home/runner/work/lxc/lxc/src/lxc/lsm/apparmor.c:442:8
    #3 0x7f720413bc2a in apparmor_prepare /home/runner/work/lxc/lxc/src/lxc/lsm/apparmor.c:1104:13
    #4 0x7f720409b6e9 in lxc_init /home/runner/work/lxc/lxc/src/lxc/start.c:848:8
    #5 0x7f72040a395a in __lxc_start /home/runner/work/lxc/lxc/src/lxc/start.c:2009:8
    #6 0x7f7203fc7186 in lxc_execute /home/runner/work/lxc/lxc/src/lxc/execute.c:99:9
    #7 0x7f7204000e44 in do_lxcapi_start /home/runner/work/lxc/lxc/src/lxc/lxccontainer.c:1112:9
    #8 0x7f7203ff0c07 in lxcapi_start /home/runner/work/lxc/lxc/src/lxc/lxccontainer.c:1149:8
    #9 0x4c6912 in main /home/runner/work/lxc/lxc/src/lxc/tools/lxc_execute.c:224:9
```

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

Merge pull request #3779 from brauner/2021-04-12/attach_fixes

attach: fixes

Revert "rexec: mark all fds as close-on-exec if possible"

This reverts commit 531d36ad009325b74a105d9d6956e320f37b2937.

Callers might want to explicilty inhert file descriptors so we can't
close them behind their back when we exec.

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

attach: don't return early when calculating namespaces via pidfd

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

Merge pull request #3778 from brauner/2021-04-12/fixes

conf: idmaptool fixes

conf: don't report success when idmaptools lack all privilege

Fixes: #3777
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

conf: simplify idmaptool_on_path_and_privileged()

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

tests: pass on ASAN/UBSAN options to several tests

to make it easier to run them under ASan/UBSan.

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

tests: stop cutting off right square brackets in share_ns

Closes https://github.com/lxc/lxc/issues/3791

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

tests: switch to the "busybox" template in lxc-test-checkpoint-restore

criu can't seem to dump systemd-logind used in Ubuntu due to what appears to be
https://github.com/checkpoint-restore/criu/issues/1430.
Let's switch to busybox where all the processes hopefully can be dumped.

Closes https://github.com/lxc/lxc/issues/3792

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

tests: fix a memory leak in attach

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

tests: fix a memory leak in cgpath

```
==131188==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 568 byte(s) in 1 object(s) allocated from:
    #0 0x7f8918943bc8 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dbc8)
    #1 0x7f89181ee5a3 in lxc_container_new /home/vagrant/lxc/src/lxc/lxccontainer.c:5264
    #2 0x55ffc5022869 in test_container /home/vagrant/lxc/src/tests/cgpath.c:176
    #3 0x55ffc5023023 in main /home/vagrant/lxc/src/tests/cgpath.c:233
    #4 0x7f891709e0b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
```

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

tests: fix a memory leak in lxcpath

```
$ sudo ./src/tests/lxc-test-lxcpath

=================================================================
==95911==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 39 byte(s) in 1 object(s) allocated from:
    #0 0x7effafc8d3dd in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x963dd)
    #1 0x7effaf5a2de6 in lxcapi_config_file_name /home/vagrant/lxc/src/lxc/lxccontainer.c:3190
    #2 0x562961680c30 in main /home/vagrant/lxc/src/tests/lxcpath.c:49
    #3 0x7effae5150b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)

Direct leak of 21 byte(s) in 1 object(s) allocated from:
    #0 0x7effafc8d3dd in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x963dd)
    #1 0x7effaf5a2de6 in lxcapi_config_file_name /home/vagrant/lxc/src/lxc/lxccontainer.c:3190
    #2 0x56296168115e in main /home/vagrant/lxc/src/tests/lxcpath.c:77
    #3 0x7effae5150b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)

Direct leak of 21 byte(s) in 1 object(s) allocated from:
    #0 0x7effafc8d3dd in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x963dd)
    #1 0x7effaf5a2de6 in lxcapi_config_file_name /home/vagrant/lxc/src/lxc/lxccontainer.c:3190
    #2 0x562961680f0a in main /home/vagrant/lxc/src/tests/lxcpath.c:63
    #3 0x7effae5150b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)

SUMMARY: AddressSanitizer: 81 byte(s) leaked in 3 allocation(s).
```

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

tests: fix a memory leak in cgpath

```
$ sudo ./src/tests/lxc-test-cgpath
Container creation tests...Passed
Container creation with LXCPATH tests...Passed

=================================================================
==57206==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 296 byte(s) in 1 object(s) allocated from:
    #0 0x7fef22c27dc6 in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10ddc6)
    #1 0x557c6e3ce3d9 in cgroup_ops_init cgroups/cgfsng.c:3347
    #2 0x557c6e3d6516 in cgroup_init cgroups/cgroup.c:33
    #3 0x557c6e3788e2 in test_running_container /home/vagrant/lxc/src/tests/cgpath.c:102
    #4 0x557c6e379c69 in test_container /home/vagrant/lxc/src/tests/cgpath.c:197
    #5 0x557c6e379e37 in main /home/vagrant/lxc/src/tests/cgpath.c:233
    #6 0x7fef2136c0b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)

Direct leak of 296 byte(s) in 1 object(s) allocated from:
    #0 0x7fef22c27dc6 in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10ddc6)
    #1 0x557c6e3ce3d9 in cgroup_ops_init cgroups/cgfsng.c:3347
    #2 0x557c6e3d6516 in cgroup_init cgroups/cgroup.c:33
    #3 0x557c6e3788e2 in test_running_container /home/vagrant/lxc/src/tests/cgpath.c:102
    #4 0x557c6e379c69 in test_container /home/vagrant/lxc/src/tests/cgpath.c:197
    #5 0x557c6e379e61 in main /home/vagrant/lxc/src/tests/cgpath.c:237
    #6 0x7fef2136c0b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
```

Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

Merge pull request #3775 from brauner/2021-04-07/fixes

confile: make lxc_get_config() and lxc_get_config_net() always return…

confile: make lxc_get_config() and lxc_get_config_net() always return non-NULL

Introduce the concept of an unsupported config item.

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

Merge pull request #3774 from stgraber/master

github: Try to fix action naming

github: Try to fix action naming

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

Merge pull request #3773 from brauner/2021-04-06/fixes_2

confile & log: fixes

confile: enforce maximum subkey length

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

log: add error_ret()

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

macro: ensure ret_errno() always returns negative

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

Merge pull request #3763 from evverx/fuzz-lxc-define-load

oss-fuzz: fuzz lxc_config_define_add and lxc_config_define_load

Merge pull request #3772 from merlin1991/master

templates/*.in: fixed PATH handling with spaces

templates/*.in: fixed PATH handling with spaces

if $PATH already contains a path with a space the append of the
default directories in all template scripts fails with an error
like the following:

/usr/share/lxc/templates/lxc-download: 69: export: (x86)/NVIDIA: bad
variable name

Signed-off-by: Christian Ratzenhofer <christian.ratzenhofer@cdnm.at>

Merge pull request #3771 from brauner/2021-04-06/fixes

conf: fix setups where /dev is outside of LXC's control

log: ensure we always return negative errno

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

conf: fix setups where /dev is outside of LXC's control

Fixes: #3770
Suggested-by: Ruben Jenster <r.jenster@drachenfels.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #3766 from brauner/2021-04-02/fixes_2

lsm: fixes

confile: complain when LXC is built without AppArmor support

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

confile: complain when LXC is built without selinux support

Link: https://github.com/lxc/lxc/issues/3765
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>