Only changing ownership back to root is not enough we also need to
change the access mode, otherwise the user might have set 666 first, and
thus allow everyone access before and after the chown().
Inspired by #12431 let's also rework chmod_and_chown() and make sure we
never add more rights to a file not owned by the right user.
Also, let's make chmod_and_chown() just a wrapper arond
fchmod_and_chown().
let's also change strategy: instead of chown()ing first and stating
after on failure and supressing errors, let's avoid the chown in the
firts place, in the interest on keeping things minimal.
This restores show_pid_array() output in legacy locales on the console.
Only one call to get_process_cmdline() is changed, all others retain
utf8-only mode. This affects systemd-cgls, systemctl status, etc, when
working locally.
Calls to get_process_cmdline() that cross a process boundary always use
utf8. It's the callers responsibility to convert this to some encoding that
they use. This means that we always pass utf8 over the bus.
It turns out that the kernel allows comm names higher than our expected limit
of 16.
$ wc -c /proc/*/comm|sort -g|tail -n3
35 /proc/1292317/comm
35 /proc/1293610/comm
36 /proc/1287112/comm
$ cat /proc/1287112/comm
kworker/u9:3-kcryptd/253:0
The functions to retrieve and print process cmdlines were based on the
assumption that they contain printable ASCII, and everything else
should be filtered out. That assumption doesn't hold in today's world,
where people are free to use unicode everywhere.
This replaces the custom cmdline reading code with a more generic approach
using utf8_escape_non_printable_full().
For kernel threads, truncation is done on the parenthesized name, so we'll
get "[worker]", "[worker…]", …, "[w…]", "[…", "…" as we reduce the number of
available columns.
This implementation is most likely slower for very long cmdlines, but I don't
think this is very important. The common case is to have short commandlines,
and should print those properly. Absurdly long cmdlines are the exception,
which needs to be handled correctly and safely, but speed is not too important.
Fixes#12532.
v2:
- use size_t for the number of columns. This change propagates into various
other functions that call get_process_cmdline(), increasing the size of the
patch, but the changes are rather trivial.
Previously used "highlight yellow" was not visible on urxvt, because it
was too light. This color is shown as bold black by urxvt, but at least
it is readable. On other terminals it is shown as various hues of yellow,
pleasant on the eyes and not too bright. The color shown on linux console
could be called orange rather than yellow, but it is still readable.
(I also tried non-highlight "yellow", but it is not as readable.)
This is a follow-up for bb40c12569.
Fix the following compile error:
src/basic/socket-util.h:187:30: error: implicit declaration of function 'strnlen'; did you mean 'strlen'? [-Werror=implicit-function-declaration]
Switching to K_UNICODE from other than L_XLATE can make the keyboard
unusable and possibly leak keypresses from X.
BugLink: https://launchpad.net/bugs/1803993
An ugly, ugly work-around for #11810. And no, we shouldn't have to do
this. This is something for AMD, the firmware or the kernel to
fix/work-around, not us. But nonetheless, this should do it for now.
Fixes: #11810
We don#t actually use all combinations, but it's kinda nice if we can
output all combinations in a test, and this is preparation so that we
can do so nicely.
three of these colors we never use, so let's drop them. Let's however
add a highlight version of grey, so that at least for all colors we do
define we have all possible styles defined.
Apparently all relevant terminals implement these sequences, including
the Linux kernel, rxvt, xterm, and of course gnome terminal. Hence it
should be OK to use them, and fixate the grey color in a way that maps
to the same color in all terminals.
Ideally we'd stick to the more symbolic colors that allow terminal
emulators to implement color styles, but this apparently doesn#t work,
since rxvt maps grey to something unreadable by default.
Note that this change has negative effects besides the non-themability
of the palette: the midrange grey this uses maps to regular white on the
linux console. However, that's probably not too bad: allowing things to
be unreadable on some terminals is probably worse than showing no color
on some terminals.
Fixes: #12482
Otherwise, the fuzzers will fail to compile with MSan:
```
../../src/systemd/src/basic/random-util.c:64:40: error: use of undeclared identifier 'sucess'; did you mean 'success'?
msan_unpoison(&success, sizeof(sucess));
^~~~~~
success
../../src/systemd/src/basic/alloc-util.h:169:50: note: expanded from macro 'msan_unpoison'
^
../../src/systemd/src/basic/random-util.c:38:17: note: 'success' declared here
uint8_t success;
^
1 error generated.
[80/545] Compiling C object 'src/basic/a6ba3eb@@basic@sta/process-util.c.o'.
ninja: build stopped: subcommand failed.
Fuzzers build failed
```
In program output, highlighting warnings with ANSI_HIGHLIGHT is not enough,
because it doesn't stand out enough. Yellow is more appropriate.
I was worried that yellow wouldn't be visible on white background, but (at
least gnome-terminal) uses a fairly dark yellow that is fully legible on white
and light-colored backgrounds. We also used yellow in many places,
e.g. systemctl, so this should be fine.
Note: yellow is unreadable on urxvt with white background (urxvt +rv). But
grey, which we already used, is also unreadable, so urxvt users would have
to disable colors anyway, so this change does not make the problem
intrinsically worse. See
https://github.com/systemd/systemd/issues/12482#issuecomment-490374210.
