Add a comment to clarify how to handle best-effort backwards
compatibility for LANDLOCK_ACCESS_FS_REFER.
The "refer" access is special because these operations are always
forbidden in ABI 1, unlike most other operations, which are permitted
when using Landlock ABI levels where they are not supported yet.
Signed-off-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20221107181651.4555-1-gnoack3000@gmail.com
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Update the sandboxer sample to restrict truncate actions. This is
automatically enabled by default if the running kernel supports
LANDLOCK_ACCESS_FS_TRUNCATE, except for the paths listed in the
LL_FS_RW environment variable.
Signed-off-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20221018182216.301684-11-gnoack3000@gmail.com
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Extend the help with the latest Landlock ABI version supported by the
sandboxer.
Inform users about the sandboxer or the kernel not being up-to-date.
Make the version check code easier to update and harder to misuse.
Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20220923154207.3311629-2-mic@digikod.net
Add LANDLOCK_ACCESS_FS_REFER to the "roughly write" access rights and
leverage the Landlock ABI version to only try to enforce it if it is
supported by the running kernel.
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Link: https://lore.kernel.org/r/20220506161102.525323-10-mic@digikod.net
Let's follow a consistent and documented coding style. Everything may
not be to our liking but it is better than tacit knowledge. Moreover,
this will help maintain style consistency between different developers.
This contains only whitespace changes.
Automatically formatted with:
clang-format-14 -i samples/landlock/*.[ch]
Link: https://lore.kernel.org/r/20220506160513.523257-8-mic@digikod.net
Cc: stable@vger.kernel.org
Signed-off-by: Mickaël Salaün <mic@digikod.net>
In preparation to a following commit, add clang-format on and
clang-format off stanzas around constant definitions. This enables to
keep aligned values, which is much more readable than packed
definitions.
Link: https://lore.kernel.org/r/20220506160513.523257-7-mic@digikod.net
Cc: stable@vger.kernel.org
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Clang static analysis reports this error
sandboxer.c:134:8: warning: Potential leak of memory
pointed to by 'path_list'
ret = 0;
^
path_list is allocated in parse_path() but never freed.
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20210428213852.2874324-1-trix@redhat.com
Cc: stable@vger.kernel.org
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Add a basic sandbox tool to launch a command which can only access a
list of file hierarchies in a read-only or read-write way.
Cc: James Morris <jmorris@namei.org>
Cc: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Reviewed-by: Jann Horn <jannh@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210422154123.13086-12-mic@digikod.net
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
Günther Noack