which(1) is not standardized by POSIX, and has different implementations
and behaviour on different distributions. The behaviour and exit status
of command -v is standardized by POSIX.
Signed-off-by: Simon McVittie <smcv@collabora.com>
Remove a redundant `PROP_0` member and add a type for the property IDs
so that the `switch` cases can be checked by `-Wswitch-enum`.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
This bundles up `{get,set}_no_interaction()` in a way which can be bound
or exposed to bindings.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
This complements `flatpak_transaction_set_no_interaction()` and allows
calling code to see if a given transaction is interactive.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
When generating flattened permissions (i.e. for --show-permissions or
for the /.flatpak-info file) we're currently flattening the permissions
i.e. don't show things that would only affect layering the permissions).
However, the code doesn't currently do this for the filesystem key, so
implement that. This means we only display the permissions that are
in effect, and don't display "negative" permissions like !host which
are not meaningful in this context.
This reintroduces the special case that existed in Flatpak 1.12.3, but
under a different name, so that it will be backwards-compatible. With
this change, flatpak-builder will be able to resolve CVE-2022-21682 by
using --filesystem=host:reset.
We want to implement this as a suffix rather than as a new keyword,
because unknown suffixes are ignored with a warning, rather than causing
a fatal error. This means that the new version of flatpak-builder will
be able to run against older versions of flatpak: it will still be
vulnerable to CVE-2022-21682 in that situation, but at least it will run.
Co-authored-by: Alexander Larsson <alexl@redhat.com>
(cherry picked from commit 5709f1aaed)
There are two reasonable interpretations for --nofilesystem=home:
either it revokes a previous --filesystem=home (as in Flatpak 1.12.2 and
older versions), or it completely forbids access to the home directory
(as in Flatpak 1.12.3). Clarify the man pages to indicate that it only
revokes a previous --filesystem=home. This will hopefully reduce
mismatches between the design and what users expect to happen, as
in flatpak#4654.
A subsequent commit will introduce a way to get the Flatpak 1.12.3
behaviour in a way that is more backwards-compatible with Flatpak 1.12.2
and older versions.
Signed-off-by: Simon McVittie <smcv@collabora.com>
(cherry picked from commit 7bbeed2b87)
This caused regressions for some previously-working use cases. For
example, some Flatpak users previously used a global
`flatpak override --nofilesystem=home` or
`flatpak override --nofilesystem=host`, but expected that individual apps
would still be able to have finer-grained filesystem access granted by the
app manifest, such as Zoom's `--filesystem=~/Documents/Zoom:create`. With
the changes in 1.12.3, this no longer has the desired result, because
`--nofilesystem=home` was special-cased to disallow inheriting the
finer-grained `--filesystem`.
This reverts commit 445bddeee6.
This reverts the initial solution to CVE-2022-21682, which we intend to
resolve differently, by introducing a new feature in Flatpak and making
use of it in a new flatpak-builder version.
Signed-off-by: Simon McVittie <smcv@collabora.com>
(cherry picked from commit 917a7f5870)
The new behaviour caused regressions in some situations that previously
worked, and will be reverted.
This reverts commit 4d11f77aa7.
Signed-off-by: Simon McVittie <smcv@collabora.com>
(cherry picked from commit dfe868d628)
This reintroduces the special case that existed in Flatpak 1.12.3, but
under a different name, so that it will be backwards-compatible. With
this change, flatpak-builder will be able to resolve CVE-2022-21682 by
using --filesystem=host:reset.
We want to implement this as a suffix rather than as a new keyword,
because unknown suffixes are ignored with a warning, rather than causing
a fatal error. This means that the new version of flatpak-builder will
be able to run against older versions of flatpak: it will still be
vulnerable to CVE-2022-21682 in that situation, but at least it will run.
Co-authored-by: Alexander Larsson <alexl@redhat.com>
There are two reasonable interpretations for --nofilesystem=home:
either it revokes a previous --filesystem=home (as in Flatpak 1.12.2 and
older versions), or it completely forbids access to the home directory
(as in Flatpak 1.12.3). Clarify the man pages to indicate that it only
revokes a previous --filesystem=home. This will hopefully reduce
mismatches between the design and what users expect to happen, as
in flatpak#4654.
A subsequent commit will introduce a way to get the Flatpak 1.12.3
behaviour in a way that is more backwards-compatible with Flatpak 1.12.2
and older versions.
Signed-off-by: Simon McVittie <smcv@collabora.com>
This caused regressions for some previously-working use cases. For
example, some Flatpak users previously used a global
`flatpak override --nofilesystem=home` or
`flatpak override --nofilesystem=host`, but expected that individual apps
would still be able to have finer-grained filesystem access granted by the
app manifest, such as Zoom's `--filesystem=~/Documents/Zoom:create`. With
the changes in 1.12.3, this no longer has the desired result, because
`--nofilesystem=home` was special-cased to disallow inheriting the
finer-grained `--filesystem`.
This reverts commit 445bddeee6.
This reverts the initial solution to CVE-2022-21682, which we intend to
resolve differently, by introducing a new feature in Flatpak and making
use of it in a new flatpak-builder version.
Signed-off-by: Simon McVittie <smcv@collabora.com>
The new behaviour caused regressions in some situations that previously
worked, and will be reverted.
This reverts commit 4d11f77aa7.
Signed-off-by: Simon McVittie <smcv@collabora.com>
We weren't distinguishing here between overrides that should have been
negated (xdg-documents) and overrides that should not have been negated
(everything else).
Signed-off-by: Simon McVittie <smcv@collabora.com>
(cherry picked from commit 4e3d1d8b7b)
Normally, we want to save a process and get better signal handling
by replacing the `flatpak run` process with bubblewrap.
However, when we're doing profiling or measuring coverage, we want to
exit cleanly so that profiling data can be recorded, which is done in
an atexit() hook. In this situation, bypass the execve() optimization;
instead, start bubblewrap in the background, immediately wait for it,
and propagate its exit status.
Signed-off-by: Simon McVittie <smcv@collabora.com>
We weren't distinguishing here between overrides that should have been
negated (xdg-documents) and overrides that should not have been negated
(everything else).
Signed-off-by: Simon McVittie <smcv@collabora.com>
Previously --nofilesystem=host only removed specifically access to the
`host` permissions, and not necessarily other filesystems (like `home`
or `/some/path`). This isn't very useful to limit access because you
don't know what other filesystems the app may have access too.
We change this to mean that `--nofilesystem=host` removes *all* filesystem
access from the parent layer, and `--nofilesystem=home` removes all
file access to the homedir and paths inside it.
The available layers are, in order:
* app permissions
* overrides
* commandline args
This allows you to start from scratch with the filesystem permissions
in the overrides or the commandline. This is a small change in
behaviour, but not a lot of things use --nofilesystem, and the ones
that do probably expects this behaviour.
This tests for invalid metadata, missing xa.metadata and mismatched
values in xa.metadata and the real metadata, including the embedded
null leading to the hidden permissions of CVE-2021-43860.
This was disables a long time ago because the fedora remotes didn't
contain metadata, but that has been added since then. Requiring fixes
a security concern where an app claims to require no permissions (by
having no metadata in commit) but then actually requires permissions
in the installed app.
If we fail to parse xa.metadata from the summary cache or the commit
xa.metadata we fail the resolve.
If xa.metadata is missing in the commit we fail the resolve (it is
always set in the summary cache, because summary update converts
missing xa.metadata to "", so we either get that, or cache miss which
leads to resolving from the commit.
This means that op->resolved_metadata is always set during install and
updates, which means we will show the app permissions. The transaction
will also always make sure that this data actually matches what gets
deployed.
Before this change an invalid metadata in the summary cache could lead
to a NULL resolved_metadata, which means we wouldn't print the app
permissions, yet we would still deploy some metadata file that could
have permissions. (NOTE: It would fail to deploy unless the
xa.metadata in the commit matched the metadata file, but in this
corner case we would't compare the summary and commit metadata, so
they may differ.)
In particular, if a null terminator is placed inside the metadata file,
Flatpak will only compare the text *before* it to the value of
xa.metadata, but the full file will be parsed when permissions are set
at runtime. This means that any app can include a null terminator in its
permissions metadata, and Flatpak will only show the user the
permissions *preceding* the terminator during install, but the
permissions *after* the terminator are applied at runtime.
Fixes GHSA-qpjc-vq3c-572j / CVE-2021-43860
Signed-off-by: Ryan Gonzalez <ryan.gonzalez@collabora.com>
