glibc appears to propagate different errors in different ways, let's fix
this up, so that our own code doesn't get confused by this.
See #6752 + #6737 for details.
Fixes: #6755
If a path passes though an autofs filesystem, then accessing
the path might trigger and automount. As systemd-tmpfiles is run before
the network is up, and as automounts are often used for networked
filesystems, this can cause a deadlock.
So chase_symlinks is enhance to accept a new flag which tells it
to check for autofs, and return -EREMOTE if autofs is found.
tmpfiles is changed to check just before acting on a path so that it
can avoid autofs even if a symlink was created earlier by tmpfiles
that would send this path through an autofs.
This fixes a deadlock that happens when /home is listed in /etc/fstab as
x-systemd.automount for an NFS directory.
Let's lock the personality to the currently set one, if nothing is
specifically specified. But do so with a grain of salt, and never
default to any exotic personality here, but only PER_LINUX or
PER_LINUX32.
> glibc exports a function called sync(), we should probably avoid
> overloading that as a variable here locally (gcc even used to warn about
> that, not sure why it doesn't anymore), to avoid confusion around what
> "if (sync)" actually means
For files which are vital to boot
1. Avoid opening any window where power loss will zero them out or worse.
I know app developers all coded to the ext3 implementation, but
the only formal documentation we have says we're broken if we actually
rely on it. E.g.
* `man mount`, search for `auto_da_alloc`.
* http://www.linux-mtd.infradead.org/faq/ubifs.html#L_atomic_change
* https://thunk.org/tytso/blog/2009/03/15/dont-fear-the-fsync/
2. If we tell the kernel we're interested in writing them to disk, it will
tell us if that fails. So at minimum, this means we play our part in
notifying the user about errors.
I refactored error-handling in `udevadm-hwdb` a little. It turns out I did
exactly the same as had already been done in the `systemd-hwdb` version,
i.e. commit d702dcd.
This new helper removes a leading /dev if there is one. We have code
doing this all over the place, let's unify this, and correct it while
we are at it, by using path_startswith() rather than startswith() to
drop the prefix.
An infiniband hardware address is 20 bytes, but sockaddr_ll.sll_addr is only 8
bytes. Explicitly ensure that sockaddr_union has enough space for infiniband
addresses, even if they run over sockaddr_ll and add a macro to compute the
proper size to pass to kernel.
This changes the symbolic name for the default gateway from "gateway" to
"_gateway". A new configuration option -Dcompat-gateway-hostname=true|false
is added. If it is set, the old name is also supported, but the new name
is used as the canonical name in either case. This is intended as a temporary
measure to make the transition easier, and the option should be removed
after a few releases, at which point only the new name will be used.
The old "gateway" name mostly works OK, but hasn't gained widespread acceptance
because of the following (potential) conflicts:
- it is completely legal to have a host called "gateway"
- there is no guarantee that "gateway" will not be registered as a TLD, even
though this currently seems unlikely. (Even then, there would be no
conflict except for the case when the top-level domain itself was being resolved.
The "gateway" or "_gateway" labels have only special meaning when the
whole name consists of a single label, so resolution of any subdomain
of the hypothetical gateway. TLD would still work OK. )
Moving to "_gateway" avoids those issues because underscores are not allowed
in host names (RFC 1123, §2.1) and avoids potential conflicts with local or
global names.
v2:
- simplify the logic to hardcode "_gateway" and allow
-Dcompat-gateway-hostname=true as a temporary measure.
These are similar to memdup() and newdup(), but reserve one extra NUL
byte at the end of the new allocation and initialize it. It's useful
when copying out data from fixed size character arrays where NUL
termination can't be assumed.
Checking for validity of a PID is relatively easy, but let's add a
helper cal for this too, in order to make things more readable and more
similar to uid_is_valid(), gid_is_valid() and friends.
Let's add a proper validation function, since validation isn't entirely
trivial. Make use of it where applicable. Also make use of
AUDIT_SESSION_INVALID where we need a marker for an invalid audit
session.
Some kdbus_flag and memfd related parts are left behind, because they
are entangled with the "legacy" dbus support.
test-bus-benchmark is switched to "manual". It was already broken before
(in the non-kdbus mode) but apparently nobody noticed. Hopefully it can
be fixed later.
Since busname units are only useful with kdbus, they weren't actively
used. This was dead code, only compile-tested. If busname units are
ever added back, it'll be cleaner to start from scratch (possibly reverting
parts of this patch).
As a follow-up for db3f45e2d2 let's do the
same for all other cases where we create a FILE* with local scope and
know that no other threads hence can have access to it.
For most cases this shouldn't change much really, but this should speed
dbus introspection and calender time formatting up a bit.
This moves pretty much all uses of getpid() over to getpid_raw(). I
didn't specifically check whether the optimization is worth it for each
replacement, but in order to keep things simple and systematic I
switched over everything at once.
Zbigniew Jędrzejewski-Szmek
Franck Bui
Lennart Poettering
NeilBrown
Yu Watanabe
Topi Miettinen
g0tar
Alan Jenkins
Jason Gunthorpe
bengal
Torstein Husebø
Jouke Witteveen
Martin Pitt
Daniel Berrange