SELinux labeling with --root/--image needs per-call context to carry an
alternate policy database and root prefix. The current LabelOps interface
has no way to pass this, forcing any solution to rely on global state.
Add a LabelContext *label_context to the label_ops callbacks and all
intermediate layers. Generic filesystem functions that most callers use
(xopenat_full, write_string_file_full, etc.) get a _label variant
carrying the extra parameter, with inline wrappers preserving the
original signatures so the vast majority of call sites remain untouched.
Signed-off-by: Simon de Vlieger <cmdr@supakeen.com>
Drop the -fundamental suffix from src/fundamental/ headers in favor of names
that match their src/basic/ or src/shared/ counterparts (e.g.
macro-fundamental.h -> macro.h, assert-fundamental.h -> assert-util.h,
cleanup-fundamental.h -> cleanup-util.h). Rename src/basic/{btrfs,label}.{c,h}
to use the -util suffix to match the existing shared/btrfs-util and
shared/label-util siblings. Rename src/shared/mkdir-label.{c,h} to mkdir.{c,h}
and src/shared/tmpfile-util-label.{c,h} to tmpfile-util.{c,h} to match the
corresponding src/basic names.
This saves us from having to come up with separate names for files that do
the same thing across tiers, and it makes it easier to move stuff between
src/fundamental, src/basic and src/shared: consumers just #include "foo.h"
and pick up whichever tier their -I path resolves to first, so call sites
don't need to be updated when an API moves between layers.
Where a higher-tier wrapper exists (e.g. src/basic/macro.h wrapping
src/fundamental/macro.h), the wrapper uses an explicit "../fundamental/foo.h"
or "../basic/foo.h" relative include for the lower-tier header. We can't use
GCC's #include_next directive for this — when the wrapper is reachable both
via same-dir-as-source lookup and via -I (e.g. -Isrc/shared) for the
directory it lives in, #include_next advances by exactly one slot in libcpp's
internal directory chain and lands on the same physical directory it was
already in, never reaching the lower-tier sibling (see make_cpp_dir() in
gcc/libcpp/files.cc:1986).
To make sure the right headers are always picked up, the include directories
are reordered so that e.g. src/shared always takes priority over src/basic and
similar for the other directories.
Co-developed-by: Claude Opus 4.7 <noreply@anthropic.com>
Split the single directory fd that chaseat() used to take into two separate
fds: a root_fd that sets the chroot boundary (symlinks may not escape it,
absolute symlinks resolve relative to it), and a dir_fd that path resolution
starts from. This makes the chroot semantics of chaseat() explicit at every
call site instead of encoding them in the CHASE_AT_RESOLVE_IN_ROOT flag,
which is removed. It also decouples the starting directory from the root
boundary, so callers can descend from any inode inside the tree without
having to reopen the root separately.
XAT_FDROOT passed as root_fd means "no containment" (host root); as dir_fd
it means "start at root_fd". For a smoother transition, AT_FDCWD is also
accepted as root_fd and treated as XAT_FDROOT. When root_fd points to a
directory that is actually the host root, it is normalized to XAT_FDROOT
up front so the existing shortcut path can kick in.
Absolute paths returned by chaseat() are now relative to root_fd, and
relative paths are relative to dir_fd. The result is absolute only when
there is no chroot boundary (root_fd is XAT_FDROOT), or when an absolute
symlink made resolution jump out of the dir_fd subtree; otherwise callers
get a relative path they can feed straight back into an openat()-style
call against dir_fd. Specifically, when dir_fd == root_fd and we're not
operating on the host's root directory, we return a relative path even if
we received an absolute path or resolved an absolute symlink to allow
passing the path directly to openat() style functions. We do this to not
have to go modify every caller of chaseat() to make sure they deal properly
with any absolute paths they might receive. Only when root_fd != dir_fd do
we have to return an absolute path to indicate that the path is relative to
root_fd and not dir_fd.
The shortcut that skips the per-component walk is reworked around a new
chase_xopenat() helper that funnels CHASE_NOFOLLOW, CHASE_MUST_BE_* and
CHASE_TRIGGER_AUTOFS through xopenat_full()'s O_NOFOLLOW, O_DIRECTORY,
XO_REGULAR, XO_SOCKET and XO_TRIGGER_AUTOMOUNT flags. As a result these
flags no longer force us off the shortcut and can be dropped from
CHASE_NO_SHORTCUT_MASK, and the old openat_opath_with_automount() helper
goes away. A CHASE_MUST_BE_ANY alias is introduced for shortcut callers
(stat/access paths) that don't go through xopenat_full() and still need
to bail on those flags locally.
All *_and_* helpers built on top of chaseat() (chase_and_openat,
chase_and_opendirat, chase_and_statat, chase_and_accessat,
chase_and_fopenat_unlocked, chase_and_unlinkat, chase_and_open_parent_at)
gain the same root_fd parameter, and every call site in the tree is
ported to the new signature.
chase_and_open() is also fixed to correctly handle CHASE_EXTRACT_FILENAME
without CHASE_PARENT.
In btrfs-progs 6.15 it is planned to add a new parameter in mkfs.btrfs
--inode-flags, that can set attributes for subvolumes, directories, and
files.
The current supported attributes are "nodatacow", to disable CoW, and
"nodatasum", to disable the checksum.
This commit extend the "Subvolunes=" option to understand the
"nodatacow" flag for subvolums only.
If RepartOffline is enabled it will build the image without loopback
devices, using the correct --inode-flags parameters.
If RepartOffline is disabled it will use loopback devices and set the
btrfs attributes accordingly.
Signed-off-by: Alberto Planas <aplanas@suse.com>
Now that the necessary functions from log.h have been moved to macro.h,
we can stop including log.h in macro.h. This requires modifying source
files all over the tree to include log.h instead.
Follow-up for 34c3d57474
O_RDONLY is dropped when O_DIRECTORY is specified, since
it's unnecessary and even arguably confusing here, as
the dir is modified.
This let's systemd-repart respect the `SOURCE_DATE_EPOCH` environment
variable when creating directories in the local tree through `CopyFiles`
or `MakeDirectories`.
To do this, we pass a timestamp `ts` to `mkdir_p_root`, which it will
use to fix up `mtime` and `atime` of the directory it creates as
well as the `mtime` of the directory it creates the other directory *in*,
as the `mtime` of the latter is modified when creating a directory in it.
For the same reason, it also needs to fixup the `mtime` of the upper
directory when copying a file into it through `CopyFiles`.
If `SOURCE_DATE_EPOCH`, times are left as is. (`UTIME_OMIT`)
This pulls this generally useful helper out of sysusers and into the
util lib, and updates the places throughout the codebase where it makes
sense to use it.
If we created the dir successfully, we let chmod_and_chown_at() do its thing
and shouldn't go into the part where we check if the existing directory has the
right permissions and ownership and possibly adjust them. The code was doing
that, by relying on the fact that chmod_and_chown_at() does not return -EEXIST.
That's probably true, but seems unnecessarilly complicated.
Follow-up for c1b1492a94.
Chasing symlinks is a core function that's used in a lot of places
so it deservers a less verbose names so let's rename it to chase()
and chaseat().
We also slightly change the pattern used for the chaseat() helpers
so we get chase_and_openat() and similar.
Before:
====
$ systemctl edit network.target
Failed to create directories for "/etc/systemd/system/network.target.d/override.conf": No such file or directory
====
After:
====
$ systemctl edit network.target
Failed to create directories for "/etc/systemd/system/network.target.d/override.conf": Permission denied
====
Fixes#26652.
-1 was used everywhere, but -EBADF or -EBADFD started being used in various
places. Let's make things consistent in the new style.
Note that there are two candidates:
EBADF 9 Bad file descriptor
EBADFD 77 File descriptor in bad state
Since we're initializating the fd, we're just assigning a value that means
"no fd yet", so it's just a bad file descriptor, and the first errno fits
better. If instead we had a valid file descriptor that became invalid because
of some operation or state change, the other errno would fit better.
In some places, initialization is dropped if unnecessary.
This effectively disables warnings about type/mode/ownership of existing
directories when recursively creating parent directories. (Or files. If there's
a file in a place we expect a directory, the code will later try to create
a file and fail. This follows the general pattern where we do (void)mkdir()
if the mkdir() is immediately followed by opening of a file.)
I was recently debugging an issue with the fstab-generator [1], and it says:
'Directory "/tmp" already exists, but has mode 0777 that is too permissive (0644 was requested), refusing.'
which is very specific but totally wrong in this context.
This output was added in 37c1d5e97d, and I still
think it is worth to do it, because if you actually *do* want the directory, if
there's something wrong, the precise error message will make it much easier to
diagnose. And we can't easily pass the information what failed up the call chain
because there are multiple things we check (ownership, permission mask, type)…
So passing a param whether to warn or not down into the library code seems like
the best solution, despite not being very elegant.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=2051285
Fixes a regression caused by 3008a6f21c.
Before the commit, when `mkdir_parents_internal()` is called from `mkdir_p()`,
it uses `_mkdir()` as `flag` is zero. But after the commit, `mkdir_safe_internal()`
is always used. Hence, if the path contains a symlink, it fails with -ENOTDIR.
To fix the issue, this makes `mkdir_p()` calls `mkdir_parents_internal()` with
MKDIR_FOLLOW_SYMLINK flag.
Fixes#22334.
Let's reduce our code duplication, and let's focus on using xyzat()
style APIs more, hence drop mkdir_errno_wrapper() and stick to
mkdirar_errno_wrapper() wherever we can, it's a true superset of
functionality after all.
Let's define two helpers strdupa_safe() + strndupa_safe() which do the
same as their non-safe counterparts, except that they abort if called
with allocations larger than ALLOCA_MAX.
This should ensure that all our alloca() based allocations are subject
to this limit.
afaics glibc offers three alloca() based APIs: alloca() itself,
strndupa() + strdupa(). With this we have now replacements for all of
them, that take the limit into account.
chase_symlinks() would return negative on error, and either a non-negative status
or a non-negative fd when CHASE_OPEN was given. This made the interface quite
complicated, because dependning on the flags used, we would get two different
"types" of return object. Coverity was always confused by this, and flagged
every use of chase_symlinks() without CHASE_OPEN as a resource leak (because it
would this that an fd is returned). This patch uses a saparate output parameter,
so there is no confusion.
(I think it is OK to have functions which return either an error or an fd. It's
only returning *either* an fd or a non-fd that is confusing.)
These lines are generally out-of-date, incomplete and unnecessary. With
SPDX and git repository much more accurate and fine grained information
about licensing and authorship is available, hence let's drop the
per-file copyright notice. Of course, removing copyright lines of others
is problematic, hence this commit only removes my own lines and leaves
all others untouched. It might be nicer if sooner or later those could
go away too, making git the only and accurate source of authorship
information.