Let's bump up the warning level, and not add by -Wextra by hand. This is the
approach recommended by meson. The idea is that all projects should be as
similar as possible to make it easier for users to switch between projects.
With meson-0.52.0-1.module_f31+6771+f5d842eb.noarch I get:
src/test/meson.build:19: WARNING: Overriding previous value of environment variable 'PATH' with a new one
When we're using *prepend*, the whole point is to modify an existing variable,
so meson shouldn't warn. But let's set avoid the warning and shorten things by
setting the final value immediately.
The code in cgroup.c has support for all hierarchies, but the test,
as written, will only work on unified. Since the test is really about
bpf code, and not the legacy devices controller, let's just skip
the test.
We already handle it specially in get_timezones(), hence we should OK it
here too, even if the timezone file doesn't actually exist.
Prompted by:
https://serverfault.com/questions/991172/invalid-time-zone-utc
(Yes, Ubuntu should install the UTC timezone data unconditionally: it
should not be an option, even if all other timezone data is excluded,
but since it's our business to validate user input but not out business
to validate distros, let's just accept "UTC" unconditionally, it's magic
after all)
It turns out that the kernel verifier would reject a program we would build
if there was a whitelist, but no entries in the whitelist matched.
The program would approximately like this:
0: (61) r2 = *(u32 *)(r1 +0)
1: (54) w2 &= 65535
2: (61) r3 = *(u32 *)(r1 +0)
3: (74) w3 >>= 16
4: (61) r4 = *(u32 *)(r1 +4)
5: (61) r5 = *(u32 *)(r1 +8)
48: (b7) r0 = 0
49: (05) goto pc+1
50: (b7) r0 = 1
51: (95) exit
and insn 50 is unreachable, which is illegal. We would then either keep a
previous version of the program or allow everything. Make sure we build a
valid program that simply rejects everything.
Most of the time, we specify the allowed access mode as "rwm", so the check
always trivially passes. In that case, skip the check.
The repeating part changes from:
5: (55) if r2 != 0x2 goto pc+6
6: (bc) w1 = w3
7: (54) w1 &= 7
8: (5d) if r1 != r3 goto pc+3
9: (55) if r4 != 0x1 goto pc+2
10: (55) if r5 != 0x3 goto pc+1
11: (05) goto pc+8
to
6: (55) if r2 != 0x2 goto pc+3
7: (55) if r4 != 0x1 goto pc+2
8: (55) if r5 != 0x3 goto pc+1
9: (05) goto pc+40
This makes the code a bit longer, but easier to read I think, because
the cgroup v1 and v2 code paths are more similar. And whent he type is
a char, any backtrace is easier to interpret.
The naming of the functions was a complete mess: the most specific functions
which don't know anything about cgroups had "cgroup_" prefix, while more
general functions which took a node path and a cgroup for reporting had no
prefix. Let's use "bpf_devices_" for the latter group, and "bpf_prog_*" for the
rest.
The main goal of this move is to split the implementation from the calling code
and add unit tests in a later patch.
64MB is not that much, but let's not be greedy, esp. because we may run
many things in parallel.
Also, rlim_cur should never be higher than rlim_max, so let's simplify our
code.
We were looking at the wrong variable, and would always crash if this
comparison was reached. Fixes#13965.
Also, fix crash (_cleanup_ called on uninitialized variable) if we failed in
error path.
While at it, let's shorten some messages.
When autoclose is set (kernel default but many distributions reverse the
setting) opening a CD-rom device causes the tray to close.
The function of blkid is to report the current state of the device and
not to change it. Hence it should use O_NONBLOCK when opening the
device to avoid closing a CD-rom tray.
blkid is used liberally in scripts so it can potentially interfere with
the user operating the CD-rom hardware.
[kzak@redhat.com: add O_NONBLOCK also to:
- wipefs
- blkid_new_probe_from_filename()
- blkid_evaluate_tag()]
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>
(cherry picked from commit 39f5af25982d8b0244000e92a9d0e0e6557d0e17)
