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>

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

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>

Merge pull request #3783 from evverx/cgpath-memleak2

tests: fix a memory leak in cgpath

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

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>

Merge pull request #3764 from brauner/2021-04-02/fixes

confile: fix lxc.namespace.share.[identifier]

confile: fix lxc.namespace.share.[identifier]

Link: https://github.com/lxc/lxc/pull/3763/files#r606089660
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #3762 from brauner/2021-03-31/fixes

fixes: Makefile, lxc-user-nic, simplify get_network_config_ops()

confile: simplify get_network_config_ops()

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

string_utils: use restrict for lxc_safe_int64_residual()

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

string_utils: ensure that errno is set on return

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

string_utils: move to lxc-copy() sources

It's the only place where it is still used.

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

lxc_user_nic: cleanup get_alloted()

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

lxc_user_nic: cleanup append_alloted()

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

Merge pull request #3760 from evverx/reject-giant-configs

oss-fuzz: reject giant configs early

cifuzz: fuzz longer

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

confile: fix a memory leak lxc_config_define_add

```
2021-04-02T05:45:54.9410345Z ==13==ERROR: LeakSanitizer: detected memory leaks
2021-04-02T05:45:54.9410737Z
2021-04-02T05:45:54.9411488Z Direct leak of 16 byte(s) in 1 object(s) allocated from:
2021-04-02T05:45:54.9412556Z     #0 0x54d752 in calloc /src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
2021-04-02T05:45:54.9413360Z     #1 0x583795 in parse_new_conf_line /src/lxc/src/lxc/confile.c:3048:8
2021-04-02T05:45:54.9414057Z     #2 0x582f1a in lxc_config_define_add /src/lxc/src/lxc/confile.c:3090:15
2021-04-02T05:45:54.9415352Z     #3 0x5810fa in LLVMFuzzerTestOneInput /src/lxc/src/tests/fuzz-lxc-define-load.c:30:6
2021-04-02T05:45:54.9419212Z     #4 0x483b93 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:599:15
2021-04-02T05:45:54.9421819Z     #5 0x48309a in fuzzer::Fuzzer::RunOne(unsigned char const*, unsigned long, bool, fuzzer::InputInfo*, bool, bool*) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:505:3
2021-04-02T05:45:54.9424205Z     #6 0x485474 in fuzzer::Fuzzer::ReadAndExecuteSeedCorpora(std::__Fuzzer::vector<fuzzer::SizedFile, fuzzer::fuzzer_allocator<fuzzer::SizedFile> >&) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:814:7
2021-04-02T05:45:54.9426658Z     #7 0x485689 in fuzzer::Fuzzer::Loop(std::__Fuzzer::vector<fuzzer::SizedFile, fuzzer::fuzzer_allocator<fuzzer::SizedFile> >&) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:845:3
2021-04-02T05:45:54.9428616Z     #8 0x473717 in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:906:6
2021-04-02T05:45:54.9429989Z     #9 0x49f572 in main /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20:10
2021-04-02T05:45:54.9433312Z     #10 0x7fa96041b83f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2083f)
2021-04-02T05:45:54.9433795Z
2021-04-02T05:45:54.9434661Z DEDUP_TOKEN: calloc--parse_new_conf_line--lxc_config_define_add
2021-04-02T05:45:54.9435483Z SUMMARY: AddressSanitizer: 16 byte(s) leaked in 1 allocation(s).
2021-04-02T05:45:54.9435958Z
2021-04-02T05:45:54.9436404Z INFO: a leak has been found in the initial corpus.
```

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

oss-fuzz: fuzz lxc_config_define_add and lxc_config_define_load

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

Merge pull request #3759 from evverx/san-compatible

build-system: make it compatible with ASan/UBsan/Msan

Merge pull request #3758 from brauner/2021-03-31/fixes

confile: cap to last bit in set_config_net_ipv4_address()

confile: cap to last bit in set_config_net_ipv4_address()

Link: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32708
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #3755 from evverx/lxc-net

oss-fuzz.sh: put the "lxc.net" keys to the seed corpus as well

Merge pull request #3756 from brauner/2021-03-30/fixes_3

string_utils: switch to path_simplify()

string_utils: switch to path_simplify()

Link: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32689
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

Merge pull request #3754 from brauner/2021-03-30/fixes_2

confile: don't jump into the global table twice

confile: don't jump into the global table twice

instead move networking keys into a subtable. This avoids even just the
remote danger of recursion and also speeds up config parsing.

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

oss-fuzz: reject giant configs early

It should help the fuzzer to avoid running into timeouts
like https://oss-fuzz.com/testcase-detail/5132999948632064.
Hopefully, once this is merged OSS-Fuzz will report only
infinite loops as timeouts.

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

build-system: make it compatible with ASan/UBsan/MSan

Closes: https://github.com/lxc/lxc/issues/3727
Signed-off-by: Evgeny Vereshchagin <evvers@ya.ru>

ci: enable PAM

to make sure pam_cgfs is buildable with ASan/UBsan too

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

ci: also build with ASan/UBsan

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

oss-fuzz.sh: get rid of the sed "no-undefined" kludge

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

ci: stop passing --enable-ubsan

It's just a follow-up to 5f404236273bb211 (where --enable-ubsan
was removed).

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

Merge pull request #3750 from brauner/2021-03-29/fixes_2

autotools: remove --enable-{asan,ubsan} in favor of --enable-sanitizers

Merge pull request #3751 from tomponline/tp-nic-ordering

doc: Documented that net type field must come before other options on the net device

doc: Documented that net type field must come before other options on the net device

Signed-off-by: Thomas Parrott <thomas.parrott@canonical.com>

README: remove Travis and add Github actions badge

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

autotools: remove --enable-{asan,ubsan} in favor of --enable-sanitizers

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

Merge pull request #3749 from brauner/2021-03-29/fixes

compiler: fix thread_local detection

Merge pull request #3746 from evverx/CIFuzz-unblock-msan

CIFuzz: turn on MSan

compiler: fix thread_local detection

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

Merge pull request #3748 from brauner/2021-03-29/fixes

fixes & config key validation

oss-fuzz.sh: put the "lxc.net" keys in the seed corpus as well

It's just a follow-up to 0abcc213e2291d71 (where the "lxc.net" keys
were moved from config_jump_table to config_jump_table_net)

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

lxccontainer: ensure second parameter to bsearch is never NULL

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

conf: fix thread_local support detection

Our detection for TLS wasn't working. Fix it.

Fixes: https://github.com/lxc/lxd/issues/8327
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

tests: add another test for garbage config key

where a valid key has trailing garbage at the end before the "=".

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

tests: fix two false negatives in parse_config_file()

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

confile: cleanup set_config_net_script_down()

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