As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
A trivial correction to convert an 'unsigned' parameter into an
'unsigned int' parameter so the prototype matches the function
definition.
I really thought that someone submitted a patch for this a few years
ago but sadly I can't find it now.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
As part of on ongoing effort to perform more automated testing and
provide more tools for individual developers to validate their
patches before submitting, we are trying to make our code
"clang-format clean". My hope is that once we have fixed all of our
style "quirks", developers will be able to run clang-format on their
patches to help avoid silly formatting problems and ensure their
changes fit in well with the rest of the SELinux kernel code.
Signed-off-by: Paul Moore <paul@paul-moore.com>
If a key has an expiration time, then when that time passes, the key is
left around for a certain amount of time before being collected (5 mins by
default) so that EKEYEXPIRED can be returned instead of ENOKEY. This is a
problem for DNS keys because we want to redo the DNS lookup immediately at
that point.
Fix this by allowing key types to be marked such that keys of that type
don't have this extra period, but are reclaimed as soon as they expire and
turn this on for dns_resolver-type keys. To make this easier to handle,
key->expiry is changed to be permanent if TIME64_MAX rather than 0.
Furthermore, give such new-style negative DNS results a 1s default expiry
if no other expiry time is set rather than allowing it to stick around
indefinitely. This shouldn't be zero as ls will follow a failing stat call
immediately with a second with AT_SYMLINK_NOFOLLOW added.
Fixes: 1a4240f476 ("DNS: Separate out CIFS DNS Resolver code")
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: Wang Lei <wang840925@gmail.com>
cc: Jeff Layton <jlayton@redhat.com>
cc: Steve French <smfrench@gmail.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: linux-cifs@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: keyrings@vger.kernel.org
cc: netdev@vger.kernel.org
Identify EVM unsupported filesystems by defining a new flag
SB_I_EVM_UNSUPPORTED.
Don't verify, write, remove or update 'security.evm' on unsupported
filesystems.
Acked-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
The security.evm HMAC and the original file signatures contain
filesystem specific data. As a result, the HMAC and signature
are not the same on the stacked and backing filesystems.
Don't copy up 'security.evm'.
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
This code is rarely (never?) enabled by distros, and it hasn't caught
anything in decades. Let's kill off this legacy debug code.
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In preparation for pre-content permission events with file access range,
move fsnotify_file_perm() hook out of security_file_permission() and into
the callers.
Callers that have the access range information call the new hook
fsnotify_file_area_perm() with the access range.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20231212094440.250945-6-amir73il@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
We would like to make changes to the fsnotify access permission hook -
add file range arguments and add the pre modify event.
In preparation for these changes, split the fsnotify_perm() hook into
fsnotify_open_perm() and fsnotify_file_perm().
This is needed for fanotify "pre content" events.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20231212094440.250945-4-amir73il@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Since commit d9250dea3f ("SELinux: add boundary support and thread
context assignment"), SELinux has been supporting assigning per-thread
security context under a constraint and the comment was updated
accordingly. However, seems like commit d84f4f992c ("CRED: Inaugurate
COW credentials") accidentally brought the old comment back that doesn't
match what the code does.
Considering the ease of understanding the code, this patch just removes the
wrong comment.
Fixes: d84f4f992c ("CRED: Inaugurate COW credentials")
Signed-off-by: Munehisa Kamata <kamatam@amazon.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Add check for strsep() in order to transfer the error.
Fixes: cd3bc044af ("KEYS: encrypted: Instantiate key with user-provided decrypted data")
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
When the machine keyring is enabled, it may be used as a trust source
for the .ima keyring. Add a reference to this in
IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY.
Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Drop useless partial kernel doc style comments. Finish/update kerneldoc
comment where there is useful information
Signed-off-by: John Johansen <john.johansen@canonical.com>
Currently, SELinux doesn't allow distinguishing between kernel threads
and userspace processes that are started before the policy is first
loaded - both get the label corresponding to the kernel SID. The only
way a process that persists from early boot can get a meaningful label
is by doing a voluntary dyntransition or re-executing itself.
Reusing the kernel label for userspace processes is problematic for
several reasons:
1. The kernel is considered to be a privileged domain and generally
needs to have a wide range of permissions allowed to work correctly,
which prevents the policy writer from effectively hardening against
early boot processes that might remain running unintentionally after
the policy is loaded (they represent a potential extra attack surface
that should be mitigated).
2. Despite the kernel being treated as a privileged domain, the policy
writer may want to impose certain special limitations on kernel
threads that may conflict with the requirements of intentional early
boot processes. For example, it is a good hardening practice to limit
what executables the kernel can execute as usermode helpers and to
confine the resulting usermode helper processes. However, a
(legitimate) process surviving from early boot may need to execute a
different set of executables.
3. As currently implemented, overlayfs remembers the security context of
the process that created an overlayfs mount and uses it to bound
subsequent operations on files using this context. If an overlayfs
mount is created before the SELinux policy is loaded, these "mounter"
checks are made against the kernel context, which may clash with
restrictions on the kernel domain (see 2.).
To resolve this, introduce a new initial SID (reusing the slot of the
former "init" initial SID) that will be assigned to any userspace
process started before the policy is first loaded. This is easy to do,
as we can simply label any process that goes through the
bprm_creds_for_exec LSM hook with the new init-SID instead of
propagating the kernel SID from the parent.
To provide backwards compatibility for existing policies that are
unaware of this new semantic of the "init" initial SID, introduce a new
policy capability "userspace_initial_context" and set the "init" SID to
the same context as the "kernel" SID unless this capability is set by
the policy.
Another small backwards compatibility measure is needed in
security_sid_to_context_core() for before the initial SELinux policy
load - see the code comment for explanation.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com>
[PM: edited comments based on feedback/discussion]
Signed-off-by: Paul Moore <paul@paul-moore.com>
In four separate functions within avtab, the same comparison logic is
used. The only difference is how the result is handled or whether there
is a unique specifier value to be checked for or used.
Extracting this functionality into the avtab_node_cmp() function unifies
the comparison logic between searching and insertion and gets rid of
duplicative code so that the implementation is easier to maintain.
Signed-off-by: Jacob Satterfield <jsatterfield.linux@gmail.com>
Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
sha1 is insecure and has colisions, thus it is not useful for even
lightweight policy hash checks. Switch to sha256, which on modern
hardware is fast enough.
Separately as per NIST Policy on Hash Functions, sha1 usage must be
withdrawn by 2030. This config option currently is one of many that
holds up sha1 usage.
Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Using full_name_hash() instead of partial_name_hash() should result
in cleaner and better performing code.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
On policy reload selinuxfs replaces two subdirectories (/booleans
and /class) with new variants. Unfortunately, that's done with
serious abuses of directory locking.
1) lock_rename() should be done to parents, not to objects being
exchanged
2) there's a bunch of reasons why it should not be done for directories
that do not have a common ancestor; most of those do not apply to
selinuxfs, but even in the best case the proof is subtle and brittle.
3) failure halfway through the creation of /class will leak
names and values arrays.
4) use of d_genocide() is also rather brittle; it's probably not much of
a bug per se, but e.g. an overmount of /sys/fs/selinuxfs/classes/shm/index
with any regular file will end up with leaked mount on policy reload.
Sure, don't do it, but...
Let's stop messing with disconnected directories; just create
a temporary (/.swapover) with no permissions for anyone (on the
level of ->permission() returing -EPERM, no matter who's calling
it) and build the new /booleans and /class in there; then
lock_rename on root and that temporary directory and d_exchange()
old and new both for class and booleans. Then unlock and use
simple_recursive_removal() to take the temporary out; it's much
more robust.
And instead of bothering with separate pathways for freeing
new (on failure halfway through) and old (on success) names/values,
do all freeing in one place. With temporaries swapped with the
old ones when we are past all possible failures.
The only user-visible difference is that /.swapover shows up
(but isn't possible to open, look up into, etc.) for the
duration of policy reload.
Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[PM: applied some fixes from Al post merge]
Signed-off-by: Paul Moore <paul@paul-moore.com>
As the kernel test robot helpfully reminded us, all of the lsm_id
instances defined inside the various LSMs should be marked as static.
The one exception is Landlock which uses its lsm_id variable across
multiple source files with an extern declaration in a header file.
Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Using the size of a void pointer is much cleaner than
BITS_PER_LONG / 8.
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
While we have a lsm_fill_user_ctx() helper function designed to make
life easier for LSMs which return lsm_ctx structs to userspace, we
didn't include all of the buffer length safety checks and buffer
padding adjustments in the helper. This led to code duplication
across the different LSMs and the possibility for mistakes across the
different LSM subsystems. In order to reduce code duplication and
decrease the chances of silly mistakes, we're consolidating all of
this code into the lsm_fill_user_ctx() helper.
The buffer padding is also modified from a fixed 8-byte alignment to
an alignment that matches the word length of the machine
(BITS_PER_LONG / 8).
Signed-off-by: Paul Moore <paul@paul-moore.com>
We should return -EINVAL if the user specifies LSM_FLAG_SINGLE without
supplying a valid lsm_ctx struct buffer.
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Zero out all of the size counters in the -E2BIG case (buffer too
small) to help make the current code a bit more robust in the face of
future code changes.
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Since IMA is not yet an LSM, don't account for it in the LSM_CONFIG_COUNT
calculation, used to limit how many LSMs can invoke security_add_hooks().
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
[PM: subject line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Add hooks for setselfattr and getselfattr. These hooks are not very
different from their setprocattr and getprocattr equivalents, and
much of the code is shared.
Cc: selinux@vger.kernel.org
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Add hooks for setselfattr and getselfattr. These hooks are not very
different from their setprocattr and getprocattr equivalents, and
much of the code is shared.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: John Johansen <john.johansen@canonical.com>
[PM: forward ported beyond v6.6 due merge window changes]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Add lsm_name_to_attr(), which translates a text string to a
LSM_ATTR value if one is available.
Add lsm_fill_user_ctx(), which fills a struct lsm_ctx, including
the trailing attribute value.
Both are used in module specific components of LSM system calls.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Reviewed-by: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Paul Moore <paul@paul-moore.com>
