The cross check permission helper macros will help simplify code
that does cross task permission checks like ptrace.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Begin the actual switch to using domain labels by storing them on
the context and converting the label to a singular profile where
possible.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Begin moving apparmor to using broader domain labels, that will allow
run time computation of domain type splitting via "stacking" of
profiles into a domain label vec.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Instead of running file revalidation lazily when read/write are called
copy selinux and revalidate the file table on exec. This avoids
extra mediation overhead in read/write and also prevents file handles
being passed through to a grand child unchecked.
Signed-off-by: John Johansen <john.johansen@canonical.com>
There are still a few places where profile replacement fails to update
and a stale profile is used for mediation. Fix this by moving to
accessing the current label through a critical section that will
always ensure mediation is using the current label regardless of
whether the tasks cred has been updated or not.
Signed-off-by: John Johansen <john.johansen@canonical.com>
There is no reason to have the small stubs that don't use domain
private functions in domain.c, instead move them to lsm.c and make
them static.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Currently lookups are restricted to a single ns component in the
path. However when namespaces are allowed to have separate views, and
scopes this will not be sufficient, as it will be possible to have
a multiple component ns path in scope.
Add some ns lookup fns() to allow this and use them.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Add a policy revision file to find the current revision of a ns's policy.
There is a revision file per ns, as well as a virtualized global revision
file in the base apparmor fs directory. The global revision file when
opened will provide the revision of the opening task namespace.
The revision file can be waited on via select/poll to detect apparmor
policy changes from the last read revision of the opened file. This
means that the revision file must be read after the select/poll other
wise update data will remain ready for reading.
Signed-off-by: John Johansen <john.johansen@canonical.com>
prefixes are used for fns/data that are not static to apparmorfs.c
with the prefixes being
aafs - special magic apparmorfs for policy namespace data
aa_sfs - for fns/data that go into securityfs
aa_fs - for fns/data that may be used in the either of aafs or
securityfs
Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
The loaddata sets cover more than just a single profile and should
be tracked at the ns level. Move the load data files under the namespace
and reference the files from the profiles via a symlink.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Dynamically allocating buffers is problematic and is an extra layer
that is a potntial point of failure and can slow down mediation.
Change path lookup to use the preallocated per cpu buffers.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Patch series "kvmalloc", v5.
There are many open coded kmalloc with vmalloc fallback instances in the
tree. Most of them are not careful enough or simply do not care about
the underlying semantic of the kmalloc/page allocator which means that
a) some vmalloc fallbacks are basically unreachable because the kmalloc
part will keep retrying until it succeeds b) the page allocator can
invoke a really disruptive steps like the OOM killer to move forward
which doesn't sound appropriate when we consider that the vmalloc
fallback is available.
As it can be seen implementing kvmalloc requires quite an intimate
knowledge if the page allocator and the memory reclaim internals which
strongly suggests that a helper should be implemented in the memory
subsystem proper.
Most callers, I could find, have been converted to use the helper
instead. This is patch 6. There are some more relying on __GFP_REPEAT
in the networking stack which I have converted as well and Eric Dumazet
was not opposed [2] to convert them as well.
[1] http://lkml.kernel.org/r/20170130094940.13546-1-mhocko@kernel.org
[2] http://lkml.kernel.org/r/1485273626.16328.301.camel@edumazet-glaptop3.roam.corp.google.com
This patch (of 9):
Using kmalloc with the vmalloc fallback for larger allocations is a
common pattern in the kernel code. Yet we do not have any common helper
for that and so users have invented their own helpers. Some of them are
really creative when doing so. Let's just add kv[mz]alloc and make sure
it is implemented properly. This implementation makes sure to not make
a large memory pressure for > PAGE_SZE requests (__GFP_NORETRY) and also
to not warn about allocation failures. This also rules out the OOM
killer as the vmalloc is a more approapriate fallback than a disruptive
user visible action.
This patch also changes some existing users and removes helpers which
are specific for them. In some cases this is not possible (e.g.
ext4_kvmalloc, libcfs_kvzalloc) because those seems to be broken and
require GFP_NO{FS,IO} context which is not vmalloc compatible in general
(note that the page table allocation is GFP_KERNEL). Those need to be
fixed separately.
While we are at it, document that __vmalloc{_node} about unsupported gfp
mask because there seems to be a lot of confusion out there.
kvmalloc_node will warn about GFP_KERNEL incompatible (which are not
superset) flags to catch new abusers. Existing ones would have to die
slowly.
[sfr@canb.auug.org.au: f2fs fixup]
Link: http://lkml.kernel.org/r/20170320163735.332e64b7@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170306103032.2540-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Andreas Dilger <adilger@dilger.ca> [ext4 part]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Boot parameters are written before apparmor is ready to answer whether
the user is policy_view_capable(). Setting the parameters at boot results
in an oops and failure to boot. Setting the parameters at boot is
obviously allowed so skip the permission check when apparmor is not
initialized.
While we are at it move the more complicated check to last.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Pull security layer updates from James Morris:
"Highlights:
- major AppArmor update: policy namespaces & lots of fixes
- add /sys/kernel/security/lsm node for easy detection of loaded LSMs
- SELinux cgroupfs labeling support
- SELinux context mounts on tmpfs, ramfs, devpts within user
namespaces
- improved TPM 2.0 support"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (117 commits)
tpm: declare tpm2_get_pcr_allocation() as static
tpm: Fix expected number of response bytes of TPM1.2 PCR Extend
tpm xen: drop unneeded chip variable
tpm: fix misspelled "facilitate" in module parameter description
tpm_tis: fix the error handling of init_tis()
KEYS: Use memzero_explicit() for secret data
KEYS: Fix an error code in request_master_key()
sign-file: fix build error in sign-file.c with libressl
selinux: allow changing labels for cgroupfs
selinux: fix off-by-one in setprocattr
tpm: silence an array overflow warning
tpm: fix the type of owned field in cap_t
tpm: add securityfs support for TPM 2.0 firmware event log
tpm: enhance read_log_of() to support Physical TPM event log
tpm: enhance TPM 2.0 PCR extend to support multiple banks
tpm: implement TPM 2.0 capability to get active PCR banks
tpm: fix RC value check in tpm2_seal_trusted
tpm_tis: fix iTPM probe via probe_itpm() function
tpm: Begin the process to deprecate user_read_timer
tpm: remove tpm_read_index and tpm_write_index from tpm.h
...
Allow a profile to carry extra data that can be queried via userspace.
This provides a means to store extra data in a profile that a trusted
helper can extract and use from live policy.
Signed-off-by: William Hua <william.hua@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Moving the use of fqname to later allows learning profiles to be based
on the fqname request instead of just the hname. It also allows cleaning
up some of the name parsing and lookup by allowing the use of
the fqlookupn_profile() lib fn.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The aad macro can replace aad strings when it is not intended to. Switch
to a fn macro so it is only applied when intended.
Also at the same time cleanup audit_data initialization by putting
common boiler plate behind a macro, and dropping the gfp_t parameter
which will become useless.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Having ops be an integer that is an index into an op name table is
awkward and brittle. Every op change requires an edit for both the
op constant and a string in the table. Instead switch to using const
strings directly, eliminating the need for the table that needs to
be kept in sync.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Verify that profiles in a load set specify the same policy ns and
audit the name of the policy ns that policy is being loaded for.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Store loaded policy and allow introspecting it through apparmorfs. This
has several uses from debugging, policy validation, and policy checkpoint
and restore for containers.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Policy management will be expanded beyond traditional unconfined root.
This will require knowning the profile of the task doing the management
and the ns view.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Prepare for a tighter pairing of user namespaces and apparmor policy
namespaces, by making the ns to be viewed available.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Prepare for a tighter pairing of user namespaces and apparmor policy
namespaces, by making the ns to be viewed available and checking
that the user namespace level is the same as the policy ns level.
This strict pairing will be relaxed once true support of user namespaces
lands.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Borrow the special null device file from selinux to "close" fds that
don't have sufficient permissions at exec time.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Instead of testing whether a given dfa exists in every code path, have
a default null dfa that is used when loaded policy doesn't provide a
dfa.
This will let us get rid of special casing and avoid dereference bugs
when special casing is missed.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The dfa is currently setup to be shared (has the basis of refcounting)
but currently can't be because the count can't be increased.
Signed-off-by: John Johansen <john.johansen@canonical.com>
When possible its better to name a learning profile after the missing
profile in question. This allows for both more informative names and
for profile reuse.
Signed-off-by: John Johansen <john.johansen@canonical.com>
prepare_ns() will need to be called from alternate views, and namespaces
will need to be created via different interfaces. So refactor and
allow specifying the view ns.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Rename to indicate the test is only about whether path mediation is used,
not whether other types of mediation might be used.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Policy namespaces will be diverging from profile management and
expanding so put it in its own file.
Signed-off-by: John Johansen <john.johansen@canonical.com>
For some obscure reason apparmor thinks its needs to locally implement
kref primitives that already exist. Stop doing this.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
the policy_lock parameter is a one way switch that prevents policy
from being further modified. Unfortunately some of the module parameters
can effectively modify policy by turning off enforcement.
split policy_admin_capable into a view check and a full admin check,
and update the admin check to test the policy_lock parameter.
Signed-off-by: John Johansen <john.johansen@canonical.com>
mediated_filesystem() should use dentry->d_sb not dentry->d_inode->i_sb and
should avoid file_inode() also since it is really dealing with the path.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull security subsystem updates from James Morris:
"In this patchset, we finally get an SELinux update, with Paul Moore
taking over as maintainer of that code.
Also a significant update for the Keys subsystem, as well as
maintenance updates to Smack, IMA, TPM, and Apparmor"
and since I wanted to know more about the updates to key handling,
here's the explanation from David Howells on that:
"Okay. There are a number of separate bits. I'll go over the big bits
and the odd important other bit, most of the smaller bits are just
fixes and cleanups. If you want the small bits accounting for, I can
do that too.
(1) Keyring capacity expansion.
KEYS: Consolidate the concept of an 'index key' for key access
KEYS: Introduce a search context structure
KEYS: Search for auth-key by name rather than target key ID
Add a generic associative array implementation.
KEYS: Expand the capacity of a keyring
Several of the patches are providing an expansion of the capacity of a
keyring. Currently, the maximum size of a keyring payload is one page.
Subtract a small header and then divide up into pointers, that only gives
you ~500 pointers on an x86_64 box. However, since the NFS idmapper uses
a keyring to store ID mapping data, that has proven to be insufficient to
the cause.
Whatever data structure I use to handle the keyring payload, it can only
store pointers to keys, not the keys themselves because several keyrings
may point to a single key. This precludes inserting, say, and rb_node
struct into the key struct for this purpose.
I could make an rbtree of records such that each record has an rb_node
and a key pointer, but that would use four words of space per key stored
in the keyring. It would, however, be able to use much existing code.
I selected instead a non-rebalancing radix-tree type approach as that
could have a better space-used/key-pointer ratio. I could have used the
radix tree implementation that we already have and insert keys into it by
their serial numbers, but that means any sort of search must iterate over
the whole radix tree. Further, its nodes are a bit on the capacious side
for what I want - especially given that key serial numbers are randomly
allocated, thus leaving a lot of empty space in the tree.
So what I have is an associative array that internally is a radix-tree
with 16 pointers per node where the index key is constructed from the key
type pointer and the key description. This means that an exact lookup by
type+description is very fast as this tells us how to navigate directly to
the target key.
I made the data structure general in lib/assoc_array.c as far as it is
concerned, its index key is just a sequence of bits that leads to a
pointer. It's possible that someone else will be able to make use of it
also. FS-Cache might, for example.
(2) Mark keys as 'trusted' and keyrings as 'trusted only'.
KEYS: verify a certificate is signed by a 'trusted' key
KEYS: Make the system 'trusted' keyring viewable by userspace
KEYS: Add a 'trusted' flag and a 'trusted only' flag
KEYS: Separate the kernel signature checking keyring from module signing
These patches allow keys carrying asymmetric public keys to be marked as
being 'trusted' and allow keyrings to be marked as only permitting the
addition or linkage of trusted keys.
Keys loaded from hardware during kernel boot or compiled into the kernel
during build are marked as being trusted automatically. New keys can be
loaded at runtime with add_key(). They are checked against the system
keyring contents and if their signatures can be validated with keys that
are already marked trusted, then they are marked trusted also and can
thus be added into the master keyring.
Patches from Mimi Zohar make this usable with the IMA keyrings also.
(3) Remove the date checks on the key used to validate a module signature.
X.509: Remove certificate date checks
It's not reasonable to reject a signature just because the key that it was
generated with is no longer valid datewise - especially if the kernel
hasn't yet managed to set the system clock when the first module is
loaded - so just remove those checks.
(4) Make it simpler to deal with additional X.509 being loaded into the kernel.
KEYS: Load *.x509 files into kernel keyring
KEYS: Have make canonicalise the paths of the X.509 certs better to deduplicate
The builder of the kernel now just places files with the extension ".x509"
into the kernel source or build trees and they're concatenated by the
kernel build and stuffed into the appropriate section.
(5) Add support for userspace kerberos to use keyrings.
KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches
KEYS: Implement a big key type that can save to tmpfs
Fedora went to, by default, storing kerberos tickets and tokens in tmpfs.
We looked at storing it in keyrings instead as that confers certain
advantages such as tickets being automatically deleted after a certain
amount of time and the ability for the kernel to get at these tokens more
easily.
To make this work, two things were needed:
(a) A way for the tickets to persist beyond the lifetime of all a user's
sessions so that cron-driven processes can still use them.
The problem is that a user's session keyrings are deleted when the
session that spawned them logs out and the user's user keyring is
deleted when the UID is deleted (typically when the last log out
happens), so neither of these places is suitable.
I've added a system keyring into which a 'persistent' keyring is
created for each UID on request. Each time a user requests their
persistent keyring, the expiry time on it is set anew. If the user
doesn't ask for it for, say, three days, the keyring is automatically
expired and garbage collected using the existing gc. All the kerberos
tokens it held are then also gc'd.
(b) A key type that can hold really big tickets (up to 1MB in size).
The problem is that Active Directory can return huge tickets with lots
of auxiliary data attached. We don't, however, want to eat up huge
tracts of unswappable kernel space for this, so if the ticket is
greater than a certain size, we create a swappable shmem file and dump
the contents in there and just live with the fact we then have an
inode and a dentry overhead. If the ticket is smaller than that, we
slap it in a kmalloc()'d buffer"
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (121 commits)
KEYS: Fix keyring content gc scanner
KEYS: Fix error handling in big_key instantiation
KEYS: Fix UID check in keyctl_get_persistent()
KEYS: The RSA public key algorithm needs to select MPILIB
ima: define '_ima' as a builtin 'trusted' keyring
ima: extend the measurement list to include the file signature
kernel/system_certificate.S: use real contents instead of macro GLOBAL()
KEYS: fix error return code in big_key_instantiate()
KEYS: Fix keyring quota misaccounting on key replacement and unlink
KEYS: Fix a race between negating a key and reading the error set
KEYS: Make BIG_KEYS boolean
apparmor: remove the "task" arg from may_change_ptraced_domain()
apparmor: remove parent task info from audit logging
apparmor: remove tsk field from the apparmor_audit_struct
apparmor: fix capability to not use the current task, during reporting
Smack: Ptrace access check mode
ima: provide hash algo info in the xattr
ima: enable support for larger default filedata hash algorithms
ima: define kernel parameter 'ima_template=' to change configured default
ima: add Kconfig default measurement list template
...
The reporting of the parent task info is a vestage from old versions of
apparmor. The need for this information was removed by unique null-
profiles before apparmor was upstreamed so remove this info from logging.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Mediation is based off of the cred but auditing includes the current
task which may not be related to the actual request.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Provide userspace the ability to introspect a sha1 hash value for each
profile currently loaded.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Add the ability to take in and report a human readable profile attachment
string for profiles so that attachment specifications can be easily
inspected.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Add basic interface files to access namespace and profile information.
The interface files are created when a profile is loaded and removed
when the profile or namespace is removed.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Allow emulating the default profile behavior from boot, by allowing
loading of a profile in the unconfined state into a new NS.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
namespaces now completely use the unconfined profile to track the
refcount and rcu freeing cycle. So rework the code to simplify (track
everything through the profile path right up to the end), and move the
rcu_head from policy base to profile as the namespace no longer needs
it.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
ns->unconfined is being used read side without locking, nor rcu but is
being updated when a namespace is removed. This works for the root ns
which is never removed but has a race window and can cause failures when
children namespaces are removed.
Also ns and ns->unconfined have a circular refcounting dependency that
is problematic and must be broken. Currently this is done incorrectly
when the namespace is destroyed.
Fix this by forward referencing unconfined via the replacedby infrastructure
instead of directly updating the ns->unconfined pointer.
Remove the circular refcount dependency by making the ns and its unconfined
profile share the same refcount.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
remove the use of replaced by chaining and move to profile invalidation
and lookup to handle task replacement.
Replacement chaining can result in large chains of profiles being pinned
in memory when one profile in the chain is use. With implicit labeling
this will be even more of a problem, so move to a direct lookup method.
Signed-off-by: John Johansen <john.johansen@canonical.com>
previously profiles had to be loaded one at a time, which could result
in cases where a replacement of a set would partially succeed, and then fail
resulting in inconsistent policy.
Allow multiple profiles to replaced "atomically" so that the replacement
either succeeds or fails for the entire set of profiles.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The sid is not going to be a direct property of a profile anymore, instead
it will be directly related to the label, and the profile will pickup
a label back reference.
For null-profiles replace the use of sid with a per namespace unique
id.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
The "permipc" command is unused and unfinished, remove it.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
John Johansen