Even though we use fallocate() it appears that file systems like btrfs
will trigger SIGBUS on certain low-disk-space situation. We should
handle that, hence catch the signal, add it to a list of invalidated
pages, and replace the page with an empty memory area. After each write
check if SIGBUS was triggered, and consider the write invalid if it was.
This should make journald a lot more robust with file systems where
fallocate() is not reliable, for example all CoW file systems
(btrfs...), where changing written data can fail with disk full errors.
https://bugzilla.redhat.com/show_bug.cgi?id=1045810
This macro calculates A / B but rounds up instead of down. We explicitly
do *NOT* use:
(A + B - 1) / A
as it suffers from an integer overflow, even though the passed values are
properly tested against overflow. Our test-cases show this behavior.
Instead, we use:
A / B + !!(A % B)
Note that on "Real CPUs" this does *NOT* result in two divisions. Instead,
instructions like idivl@x86 provide both, the quotient and the remainder.
Therefore, both algorithms should perform equally well (I didn't verify
this, though).
This file was introduced with linux-3.2, use it instead of probing for it
via prctl(PR_CAPBSET_READ).
For now, keep the old code for backwards compat. We can drop it once 3.2
is our lowest requirement.
The test-cap-list code is extended to verify cap_last_cap() is the same as
we'd get via prctl probing and /proc.
In test_raw_clone, make sure the cloned thread calls _exit() and in the parent
thread call waitpid(..., __WCLONE) to wait for the child thread to terminate,
otherwise there is a race condition where the child thread will log to the
console after the test process has already exited and the assertion from the
child thread might not be enforced.
The absence of this patch might also create problems for other tests that would
be added after this one, since potentially both parent and child would run
those tests as the child would continue running.
Tested by confirming that the logs from the child are printed before the test
terminates and that a false assertion in the child aborts the test with a core
dump.
[zj: also add check for the return value.]
The new test-cap-list introduced in commit 2822da4fb7 uses the included
table of capabilities. However, it uses cap_last_cap() which probes the kernel
for the last available capability. On an older kernel (e.g. 3.10 from RHEL 7)
that causes the test to fail with the following message:
Assertion '!capability_to_name(cap_last_cap()+1)' failed at src/test/test-cap-list.c:30, function main(). Aborting.
Fix it by exporting the size of the static table and using it in the test
instead of the dynamic one from the current kernel.
Tested by successfully running ./test-cap-list and the whole `make check` test
suite with this patch on a RHEL 7 host.
We originally only supported escaping ucs2 encoded characters (as \uxxxx). This
only covers the BMP. Support escaping also utf16 surrogate pairs (on the form
\uxxxx\uyyyy) to cover all of unicode.
The handling of the command name and other arguments is unified. This
simplifies things and should make them more predictable for users.
Incidentally, this makes ExecStart handling match the .desktop file
specification, apart for the requirment for an absolute path.
https://bugs.freedesktop.org/show_bug.cgi?id=86171
Commit a2a5291b3f changed the parser to reject unfinished quoted
strings. Unfortunately it introduced an error where a trailing
backslash would case an infinite loop. Of course this must fixed, but
the question is what to to instead. Allowing trailing backslashes and
treating them as normal characters would be one option, but this seems
suboptimal. First, there would be inconsistency between handling of
quoting and of backslashes. Second, a trailing backslash is most
likely an error, at it seems better to point it out to the user than
to try to continue.
Updated rules:
ExecStart=/bin/echo \\ → OK, prints a backslash
ExecStart=/bin/echo \ → error
ExecStart=/bin/echo "x → error
ExecStart=/bin/echo "x"y → error
fork() is not async-signal-safe and calling it from the signal handler
could result in a deadlock when at_fork() handlers are called. Using
the raw clone() syscall sidesteps that problem.
The tricky part is that raise() does not work, since getpid() does not
work. Add raw_getpid() to get the real pid, and use kill() instead of
raise().
https://bugs.freedesktop.org/show_bug.cgi?id=86604
Also, rename filename_is_safe() to filename_is_valid(), since it
actually does a full validation for what the kernel will accept as file
name, it's not just a heuristic.
Lennart Poettering
Dave Reisner
Veres Lajos
David Herrmann
Tom Gundersen
Filipe Brandenburger
Zbigniew Jędrzejewski-Szmek
Thomas Hindoe Paaboel Andersen
Ronny Chevalier
Torstein Husebø
Jan Synacek
WaLyong Cho