| Age | Commit message (Collapse) | Author |
|---|
|
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull selinux updates from Paul Moore:
- Add support for measuring the SELinux state and policy capabilities
using IMA.
- A handful of SELinux/NFS patches to compare the SELinux state of one
mount with a set of mount options. Olga goes into more detail in the
patch descriptions, but this is important as it allows more
flexibility when using NFS and SELinux context mounts.
- Properly differentiate between the subjective and objective LSM
credentials; including support for the SELinux and Smack. My clumsy
attempt at a proper fix for AppArmor didn't quite pass muster so John
is working on a proper AppArmor patch, in the meantime this set of
patches shouldn't change the behavior of AppArmor in any way. This
change explains the bulk of the diffstat beyond security/.
- Fix a problem where we were not properly terminating the permission
list for two SELinux object classes.
* tag 'selinux-pr-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: add proper NULL termination to the secclass_map permissions
smack: differentiate between subjective and objective task credentials
selinux: clarify task subjective and objective credentials
lsm: separate security_task_getsecid() into subjective and objective variants
nfs: account for selinux security context when deciding to share superblock
nfs: remove unneeded null check in nfs_fill_super()
lsm,selinux: add new hook to compare new mount to an existing mount
selinux: fix misspellings using codespell tool
selinux: fix misspellings using codespell tool
selinux: measure state and policy capabilities
selinux: Allow context mounts for unpriviliged overlayfs
|
|
Let's drop the pr_err()s from sel_make_policy_nodes() and just add one
pr_warn_ratelimited() call to the sel_make_policy_nodes() error path in
sel_write_load().
Changing from error to warning makes sense, since after 02a52c5c8c3b
("selinux: move policy commit after updating selinuxfs"), this error
path no longer leads to a broken selinuxfs tree (it's just kept in the
original state and policy load is aborted).
I also added _ratelimited to be consistent with the other prtin in the
same function (it's probably not necessary, but can't really hurt...
there are likely more important error messages to be printed when
filesystem entry creation starts erroring out).
Suggested-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Commit 02a52c5c8c3b ("selinux: move policy commit after updating
selinuxfs") moved the selinux_policy_commit() call out of
security_load_policy() into sel_write_load(), which caused a subtle yet
rather serious bug.
The problem is that security_load_policy() passes a reference to the
convert_params local variable to sidtab_convert(), which stores it in
the sidtab, where it may be accessed until the policy is swapped over
and RCU synchronized. Before 02a52c5c8c3b, selinux_policy_commit() was
called directly from security_load_policy(), so the convert_params
pointer remained valid all the way until the old sidtab was destroyed,
but now that's no longer the case and calls to sidtab_context_to_sid()
on the old sidtab after security_load_policy() returns may cause invalid
memory accesses.
This can be easily triggered using the stress test from commit
ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve
performance"):
```
function rand_cat() {
echo $(( $RANDOM % 1024 ))
}
function do_work() {
while true; do
echo -n "system_u:system_r:kernel_t:s0:c$(rand_cat),c$(rand_cat)" \
>/sys/fs/selinux/context 2>/dev/null || true
done
}
do_work >/dev/null &
do_work >/dev/null &
do_work >/dev/null &
while load_policy; do echo -n .; sleep 0.1; done
kill %1
kill %2
kill %3
```
Fix this by allocating the temporary sidtab convert structures
dynamically and passing them among the
selinux_policy_{load,cancel,commit} functions.
Fixes: 02a52c5c8c3b ("selinux: move policy commit after updating selinuxfs")
Cc: stable@vger.kernel.org
Tested-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: merge fuzz in security.h and services.c]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
If sel_make_policy_nodes() fails, we should jump to 'out', not 'out1',
as the latter would incorrectly log an MAC_POLICY_LOAD audit record,
even though the policy hasn't actually been reloaded. The 'out1' jump
label now becomes unused and can be removed.
Fixes: 02a52c5c8c3b ("selinux: move policy commit after updating selinuxfs")
Cc: stable@vger.kernel.org
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
SELinux stores the configuration state and the policy capabilities
in kernel memory. Changes to this data at runtime would have an impact
on the security guarantees provided by SELinux. Measuring this data
through IMA subsystem provides a tamper-resistant way for
an attestation service to remotely validate it at runtime.
Measure the configuration state and policy capabilities by calling
the IMA hook ima_measure_critical_data().
To enable SELinux data measurement, the following steps are required:
1, Add "ima_policy=critical_data" to the kernel command line arguments
to enable measuring SELinux data at boot time.
For example,
BOOT_IMAGE=/boot/vmlinuz-5.11.0-rc3+ root=UUID=fd643309-a5d2-4ed3-b10d-3c579a5fab2f ro nomodeset security=selinux ima_policy=critical_data
2, Add the following rule to /etc/ima/ima-policy
measure func=CRITICAL_DATA label=selinux
Sample measurement of SELinux state and policy capabilities:
10 2122...65d8 ima-buf sha256:13c2...1292 selinux-state 696e...303b
Execute the following command to extract the measured data
from the IMA's runtime measurements list:
grep "selinux-state" /sys/kernel/security/integrity/ima/ascii_runtime_measurements | tail -1 | cut -d' ' -f 6 | xxd -r -p
The output should be a list of key-value pairs. For example,
initialized=1;enforcing=0;checkreqprot=1;network_peer_controls=1;open_perms=1;extended_socket_class=1;always_check_network=0;cgroup_seclabel=1;nnp_nosuid_transition=1;genfs_seclabel_symlinks=0;
To verify the measurement is consistent with the current SELinux state
reported on the system, compare the integer values in the following
files with those set in the IMA measurement (using the following commands):
- cat /sys/fs/selinux/enforce
- cat /sys/fs/selinux/checkreqprot
- cat /sys/fs/selinux/policy_capabilities/[capability_file]
Note that the actual verification would be against an expected state
and done on a separate system (likely an attestation server) requiring
"initialized=1;enforcing=1;checkreqprot=0;"
for a secure state and then whatever policy capabilities are actually
set in the expected policy (which can be extracted from the policy
itself via seinfo, for example).
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Suggested-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
All of these are never modified outside initcalls, so they can be
__ro_after_init.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
It is not referenced outside selinuxfs.c, so remove its extern header
declaration and make it static.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
checkreqprot data member in selinux_state struct is accessed directly by
SELinux functions to get and set. This could cause unexpected read or
write access to this data member due to compiler optimizations and/or
compiler's reordering of access to this field.
Add helper functions to get and set checkreqprot data member in
selinux_state struct. These helper functions use READ_ONCE and
WRITE_ONCE macros to ensure atomic read or write of memory for
this data member.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Suggested-by: Paul Moore <paul@paul-moore.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Remove the security_policydb_len() calls from sel_open_policy() and
instead update the inode size from the size returned from
security_read_policy().
Since after this change security_policydb_len() is only called from
security_load_policy(), remove it entirely and just open-code it there.
Also, since security_load_policy() is always called with policy_mutex
held, make it dereference the policy pointer directly and drop the
unnecessary RCU locking.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Move the mutex used to synchronize policy changes (reloads and setting
of booleans) from selinux_fs_info to selinux_state and use it in
lockdep checks for rcu_dereference_protected() calls in the security
server functions. This makes the dependency on the mutex explicit
in the code rather than relying on comments.
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
In order to avoid concurrency issues around selinuxfs resource availability
during policy load, we first create new directories out of tree for
reloaded resources, then swap them in, and finally delete the old versions.
This fix focuses on concurrency in each of the two subtrees swapped, and
not concurrency between the trees. This means that it is still possible
that subsequent reads to eg the booleans directory and the class directory
during a policy load could see the old state for one and the new for the other.
The problem of ensuring that policy loads are fully atomic from the perspective
of userspace is larger than what is dealt with here. This commit focuses on
ensuring that the directories contents always match either the new or the old
policy state from the perspective of userspace.
In the previous implementation, on policy load /sys/fs/selinux is updated
by deleting the previous contents of
/sys/fs/selinux/{class,booleans} and then recreating them. This means
that there is a period of time when the contents of these directories do not
exist which can cause race conditions as userspace relies on them for
information about the policy. In addition, it means that error recovery in
the event of failure is challenging.
In order to demonstrate the race condition that this series fixes, you
can use the following commands:
while true; do cat /sys/fs/selinux/class/service/perms/status
>/dev/null; done &
while true; do load_policy; done;
In the existing code, this will display errors fairly often as the class
lookup fails. (In normal operation from systemd, this would result in a
permission check which would be allowed or denied based on policy settings
around unknown object classes.) After applying this patch series you
should expect to no longer see such error messages.
Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Switch class and policy_capabilities directory names to be referred to with
global constants, consistent with booleans directory name. This will allow
for easy consistency of naming in future development.
Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Make sel_make_bools and sel_make_classes take the specific elements of
selinux_fs_info that they need rather than the entire struct.
This will allow a future patch to pass temporary elements that are not in
the selinux_fs_info struct to these functions so that the original elements
can be preserved until we are ready to perform the switch over.
Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Separating the cleanup from the creation will simplify two things in
future patches in this series. First, the creation can be made generic,
to create directories not tied to the selinux_fs_info structure. Second,
we will ultimately want to reorder creation and deletion so that the
deletions aren't performed until the new directory structures have already
been moved into place.
Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
With the refactoring of the policy load logic in the security
server from the previous change, it is now possible to split out
the committing of the new policy from security_load_policy() and
perform it only after successful updating of selinuxfs. Change
security_load_policy() to return the newly populated policy
data structures to the caller, export selinux_policy_commit()
for external callers, and introduce selinux_policy_cancel() to
provide a way to cancel the policy load in the event of an error
during updating of the selinuxfs directory tree. Further, rework
the interfaces used by selinuxfs to get information from the policy
when creating the new directory tree to take and act upon the
new policy data structure rather than the current/active policy.
Update selinuxfs to use these updated and new interfaces. While
we are here, stop re-creating the policy_capabilities directory
on each policy load since it does not depend on the policy, and
stop trying to create the booleans and classes directories during
the initial creation of selinuxfs since no information is available
until first policy load.
After this change, a failure while updating the booleans and class
directories will cause the entire policy load to be canceled, leaving
the original policy intact, and policy load notifications to userspace
will only happen after a successful completion of updating those
directories. This does not (yet) provide full atomicity with respect
to the updating of the directory trees themselves.
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Remove initial SIDs that have never been used or are no longer used by
the kernel from its string table, which is also used to generate the
SECINITSID_* symbols referenced in code. Update the code to
gracefully handle the fact that these can now be NULL. Stop treating
it as an error if a policy defines additional initial SIDs unknown to
the kernel. Do not load unused initial SID contexts into the sidtab.
Fix the incorrect usage of the name from the ocontext in error
messages when loading initial SIDs since these are not presently
written to the kernel policy and are therefore always NULL.
After this change, it is possible to safely reclaim and reuse some of
the unused initial SIDs without compatibility issues. Specifically,
unused initial SIDs that were being assigned the same context as the
unlabeled initial SID in policies can be reclaimed and reused for
another purpose, with existing policies still treating them as having
the unlabeled context and future policies having the option of mapping
them to a more specific context. For example, this could have been
used when the infiniband labeling support was introduced to define
initial SIDs for the default pkey and endport SIDs similar to the
handling of port/netif/node SIDs rather than always using
SECINITSID_UNLABELED as the default.
The set of safely reclaimable unused initial SIDs across all known
policies is igmp_packet (13), icmp_socket (14), tcp_socket (15), kmod
(24), policy (25), and scmp_packet (26); these initial SIDs were
assigned the same context as unlabeled in all known policies including
mls. If only considering non-mls policies (i.e. assuming that mls
users always upgrade policy with their kernels), the set of safely
reclaimable unused initial SIDs further includes file_labels (6), init
(7), sysctl_modprobe (16), and sysctl_fs (18) through sysctl_dev (23).
Adding new initial SIDs beyond SECINITSID_NUM to policy unfortunately
became a fatal error in commit 24ed7fdae669 ("selinux: use separate
table for initial SID lookup") and even before that it could cause
problems on a policy reload (collision between the new initial SID and
one allocated at runtime) ever since commit 42596eafdd75 ("selinux:
load the initial SIDs upon every policy load") so we cannot safely
start adding new initial SIDs to policies beyond SECINITSID_NUM (27)
until such a time as all such kernels do not need to be supported and
only those that include this commit are relevant. That is not a big
deal since we haven't added a new initial SID since 2004 (v2.6.7) and
we have plenty of unused ones we can reclaim if we truly need one.
If we want to avoid the wasted storage in initial_sid_to_string[]
and/or sidtab->isids[] for the unused initial SIDs, we could introduce
an indirection between the kernel initial SID values and the policy
initial SID values and just map the policy SID values in the ocontexts
to the kernel values during policy_load_isids(). Originally I thought
we'd do this by preserving the initial SID names in the kernel policy
and creating a mapping at load time like we do for the security
classes and permissions but that would require a new kernel policy
format version and associated changes to libsepol/checkpolicy and I'm
not sure it is justified. Simpler approach is just to create a fixed
mapping table in the kernel from the existing fixed policy values to
the kernel values. Less flexible but probably sufficient.
A separate selinux userspace change was applied in
https://github.com/SELinuxProject/selinux/commit/8677ce5e8f592950ae6f14cea1b68a20ddc1ac25
to enable removal of most of the unused initial SID contexts from
policies, but there is no dependency between that change and this one.
That change permits removing all of the unused initial SID contexts
from policy except for the fs and sysctl SID contexts. The initial
SID declarations themselves would remain in policy to preserve the
values of subsequent ones but the contexts can be dropped. If/when
the kernel decides to reuse one of them, future policies can change
the name and start assigning a context again without breaking
compatibility.
Here is how I would envision staging changes to the initial SIDs in a
compatible manner after this commit is applied:
1. At any time after this commit is applied, the kernel could choose
to reclaim one of the safely reclaimable unused initial SIDs listed
above for a new purpose (i.e. replace its NULL entry in the
initial_sid_to_string[] table with a new name and start using the
newly generated SECINITSID_name symbol in code), and refpolicy could
at that time rename its declaration of that initial SID to reflect its
new purpose and start assigning it a context going
forward. Existing/old policies would map the reclaimed initial SID to
the unlabeled context, so that would be the initial default behavior
until policies are updated. This doesn't depend on the selinux
userspace change; it will work with existing policies and userspace.
2. In 6 months or so we'll have another SELinux userspace release that
will include the libsepol/checkpolicy support for omitting unused
initial SID contexts.
3. At any time after that release, refpolicy can make that release its
minimum build requirement and drop the sid context statements (but not
the sid declarations) for all of the unused initial SIDs except for
fs and sysctl, which must remain for compatibility on policy
reload with old kernels and for compatibility with kernels that were
still using SECINITSID_SYSCTL (< 2.6.39). This doesn't depend on this
kernel commit; it will work with previous kernels as well.
4. After N years for some value of N, refpolicy decides that it no
longer cares about policy reload compatibility for kernels that
predate this kernel commit, and refpolicy drops the fs and sysctl
SID contexts from policy too (but retains the declarations).
5. After M years for some value of M, the kernel decides that it no
longer cares about compatibility with refpolicies that predate step 4
(dropping the fs and sysctl SIDs), and those two SIDs also become
safely reclaimable. This step is optional and need not ever occur unless
we decide that the need to reclaim those two SIDs outweighs the
compatibility cost.
6. After O years for some value of O, refpolicy decides that it no
longer cares about policy load (not just reload) compatibility for
kernels that predate this kernel commit, and both kernel and refpolicy
can then start adding and using new initial SIDs beyond 27. This does
not depend on the previous change (step 5) and can occur independent
of it.
Fixes: https://github.com/SELinuxProject/selinux-kernel/issues/12
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Since it is fixed-size after allocation and we know the size beforehand,
using a plain old array is simpler and more efficient.
While there, also fix signedness of some related variables/parameters.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
If seq_file .next function does not change position index,
read after some lseek can generate unexpected output.
$ dd if=/sys/fs/selinux/avc/cache_stats # usual output
lookups hits misses allocations reclaims frees
817223 810034 7189 7189 6992 7037
1934894 1926896 7998 7998 7632 7683
1322812 1317176 5636 5636 5456 5507
1560571 1551548 9023 9023 9056 9115
0+1 records in
0+1 records out
189 bytes copied, 5,1564e-05 s, 3,7 MB/s
$# read after lseek to midle of last line
$ dd if=/sys/fs/selinux/avc/cache_stats bs=180 skip=1
dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset
056 9115 <<<< end of last line
1560571 1551548 9023 9023 9056 9115 <<< whole last line once again
0+1 records in
0+1 records out
45 bytes copied, 8,7221e-05 s, 516 kB/s
$# read after lseek beyond end of of file
$ dd if=/sys/fs/selinux/avc/cache_stats bs=1000 skip=1
dd: /sys/fs/selinux/avc/cache_stats: cannot skip to specified offset
1560571 1551548 9023 9023 9056 9115 <<<< generates whole last line
0+1 records in
0+1 records out
36 bytes copied, 9,0934e-05 s, 396 kB/s
https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Deprecate setting the SELinux checkreqprot tunable to 1 via kernel
parameter or /sys/fs/selinux/checkreqprot. Setting it to 0 is left
intact for compatibility since Android and some Linux distributions
do so for security and treat an inability to set it as a fatal error.
Eventually setting it to 0 will become a no-op and the kernel will
stop using checkreqprot's value internally altogether.
checkreqprot was originally introduced as a compatibility mechanism
for legacy userspace and the READ_IMPLIES_EXEC personality flag.
However, if set to 1, it weakens security by allowing mappings to be
made executable without authorization by policy. The default value
for the SECURITY_SELINUX_CHECKREQPROT_VALUE config option was changed
from 1 to 0 in commit 2a35d196c160e3 ("selinux: change
CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE default") and both Android
and Linux distributions began explicitly setting
/sys/fs/selinux/checkreqprot to 0 some time ago.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Deprecate the CONFIG_SECURITY_SELINUX_DISABLE functionality. The
code was originally developed to make it easier for Linux
distributions to support architectures where adding parameters to the
kernel command line was difficult. Unfortunately, supporting runtime
disable meant we had to make some security trade-offs when it came to
the LSM hooks, as documented in the Kconfig help text:
NOTE: selecting this option will disable the '__ro_after_init'
kernel hardening feature for security hooks. Please consider
using the selinux=0 boot parameter instead of enabling this
option.
Fortunately it looks as if that the original motivation for the
runtime disable functionality is gone, and Fedora/RHEL appears to be
the only major distribution enabling this capability at build time
so we are now taking steps to remove it entirely from the kernel.
The first step is to mark the functionality as deprecated and print
an error when it is used (what this patch is doing). As Fedora/RHEL
makes progress in transitioning the distribution away from runtime
disable, we will introduce follow-up patches over several kernel
releases which will block for increasing periods of time when the
runtime disable is used. Finally we will remove the option entirely
once we believe all users have moved to the kernel cmdline approach.
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
The return value of snprintf maybe over the size of TMPBUFLEN, use
scnprintf instead in sel_read_class and sel_read_perm.
Signed-off-by: liuyang34 <liuyang34@xiaomi.com>
[PM: cleaned up the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Rename selinux_enabled to selinux_enabled_boot to make it clear that
it only reflects whether SELinux was enabled at boot. Replace the
references to it in the MAC_STATUS audit log in sel_write_enforce()
with hardcoded "1" values because this code is only reachable if SELinux
is enabled and does not change its value, and update the corresponding
MAC_STATUS audit log in sel_write_disable(). Stop clearing
selinux_enabled in selinux_disable() since it is not used outside of
initialization code that runs before selinux_disable() can be reached.
Mark both selinux_enabled_boot and selinux_enforcing_boot as __initdata
since they are only used in initialization code.
Wrap the disabled field in the struct selinux_state with
CONFIG_SECURITY_SELINUX_DISABLE since it is only used for
runtime disable.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
This replaces the reverse table lookup and reverse cache with a
hashtable which improves cache-miss reverse-lookup times from
O(n) to O(1)* and maintains the same performance as a reverse
cache hit.
This reduces the time needed to add a new sidtab entry from ~500us
to 5us on a Pixel 3 when there are ~10,000 sidtab entries.
The implementation uses the kernel's generic hashtable API,
It uses the context's string represtation as the hash source,
and the kernels generic string hashing algorithm full_name_hash()
to reduce the string to a 32 bit value.
This change also maintains the improvement introduced in
commit ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve
performance") which removed the need to keep the current sidtab
locked during policy reload. It does however introduce periodic
locking of the target sidtab while converting the hashtable. Sidtab
entries are never modified or removed, so the context struct stored
in the sid_to_context tree can also be used for the context_to_sid
hashtable to reduce memory usage.
This bug was reported by:
- On the selinux bug tracker.
BUG: kernel softlockup due to too many SIDs/contexts #37
https://github.com/SELinuxProject/selinux-kernel/issues/37
- Jovana Knezevic on Android's bugtracker.
Bug: 140252993
"During multi-user performance testing, we create and remove users
many times. selinux_android_restorecon_pkgdir goes from 1ms to over
20ms after about 200 user creations and removals. Accumulated over
~280 packages, that adds a significant time to user creation,
making perf benchmarks unreliable."
* Hashtable lookup is only O(1) when n < the number of buckets.
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Reported-by: Stephen Smalley <sds@tycho.nsa.gov>
Reported-by: Jovana Knezevic <jovanak@google.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Tested-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: subj tweak, removed changelog from patch description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Load size was limited to 64MB, this was legacy limitation due to vmalloc()
which was removed a while ago.
Signed-off-by: zhanglin <zhang.lin16@zte.com.cn>
[PM: removed comments in the description about 'real world use cases']
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount updates from Al Viro:
"The first part of mount updates.
Convert filesystems to use the new mount API"
* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
mnt_init(): call shmem_init() unconditionally
constify ksys_mount() string arguments
don't bother with registering rootfs
init_rootfs(): don't bother with init_ramfs_fs()
vfs: Convert smackfs to use the new mount API
vfs: Convert selinuxfs to use the new mount API
vfs: Convert securityfs to use the new mount API
vfs: Convert apparmorfs to use the new mount API
vfs: Convert openpromfs to use the new mount API
vfs: Convert xenfs to use the new mount API
vfs: Convert gadgetfs to use the new mount API
vfs: Convert oprofilefs to use the new mount API
vfs: Convert ibmasmfs to use the new mount API
vfs: Convert qib_fs/ipathfs to use the new mount API
vfs: Convert efivarfs to use the new mount API
vfs: Convert configfs to use the new mount API
vfs: Convert binfmt_misc to use the new mount API
convenience helper: get_tree_single()
convenience helper get_tree_nodev()
vfs: Kill sget_userns()
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
"Bug fixes, code clean up, and new features:
- IMA policy rules can be defined in terms of LSM labels, making the
IMA policy dependent on LSM policy label changes, in particular LSM
label deletions. The new environment, in which IMA-appraisal is
being used, frequently updates the LSM policy and permits LSM label
deletions.
- Prevent an mmap'ed shared file opened for write from also being
mmap'ed execute. In the long term, making this and other similar
changes at the VFS layer would be preferable.
- The IMA per policy rule template format support is needed for a
couple of new/proposed features (eg. kexec boot command line
measurement, appended signatures, and VFS provided file hashes).
- Other than the "boot-aggregate" record in the IMA measuremeent
list, all other measurements are of file data. Measuring and
storing the kexec boot command line in the IMA measurement list is
the first buffer based measurement included in the measurement
list"
* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
integrity: Introduce struct evm_xattr
ima: Update MAX_TEMPLATE_NAME_LEN to fit largest reasonable definition
KEXEC: Call ima_kexec_cmdline to measure the boot command line args
IMA: Define a new template field buf
IMA: Define a new hook to measure the kexec boot command line arguments
IMA: support for per policy rule template formats
integrity: Fix __integrity_init_keyring() section mismatch
ima: Use designated initializers for struct ima_event_data
ima: use the lsm policy update notifier
LSM: switch to blocking policy update notifiers
x86/ima: fix the Kconfig dependency for IMA_ARCH_POLICY
ima: Make arch_policy_entry static
ima: prevent a file already mmap'ed write to be mmap'ed execute
x86/ima: check EFI SetupMode too
|
|
Convert the selinuxfs filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.
See Documentation/filesystems/mount_api.txt for more information.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Paul Moore <paul@paul-moore.com>
cc: Stephen Smalley <sds@tycho.nsa.gov>
cc: Eric Paris <eparis@parisplace.org>
cc: selinux@vger.kernel.org
cc: linux-security-module@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
Atomic policy updaters are not very useful as they cannot
usually perform the policy updates on their own. Since it
seems that there is no strict need for the atomicity,
switch to the blocking variant. While doing so, rename
the functions accordingly.
Signed-off-by: Janne Karhunen <janne.karhunen@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 135 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081036.435762997@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Don't use the inode->i_security pointer directly.
Provide a helper function that provides the security blob pointer.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull SELinux updates from Paul Moore:
"There are 16 patches in here but really only one that is of any
significance. That one patch is by nixiaoming and fixes a few places
where we were not properly cleaning up dentry and inode objects in the
selinuxfs error handling code. The rest are either printk->pr_*
conversions, constification tweaks, and a minor tweak to MAINTAINERS.
Everything passes the selinux-testsuite and looks to merge cleanly
against your master branch"
* tag 'selinux-pr-20180814' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: cleanup dentry and inodes on error in selinuxfs
selinux: constify write_op[]
selinux: Cleanup printk logging in netnode
selinux: Cleanup printk logging in avc
selinux: Cleanup printk logging in netif
selinux: Cleanup printk logging in netport
selinux: Cleanup printk logging in sidtab
selinux: Cleanup printk logging in netlink
selinux: Cleanup printk logging in selinuxfs
selinux: Cleanup printk logging in services
selinux: Cleanup printk logging in avtab
selinux: Cleanup printk logging in hooks
selinux: Cleanup printk logging in policydb
selinux: Cleanup printk logging in ebitmap
selinux: Cleanup printk logging in conditional
MAINTAINERS: update the LSM and SELinux subsystems
|
|
If the resource requested by d_alloc_name is not added to the linked
list through d_add, then dput needs to be called to release the
subsequent abnormal branch to avoid resource leakage.
Add missing dput to selinuxfs.c
Signed-off-by: nixiaoming <nixiaoming@huawei.com>
[PM: tweak the subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
write_op[] is never modified, so make it 'const'.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull selinux fix from Paul Moore:
"One fairly straightforward patch to fix a longstanding issue where a
process could stall while accessing files in selinuxfs and block
everyone else due to a held mutex.
The patch passes all our tests and looks to apply cleanly to your
current tree"
* tag 'selinux-pr-20180629' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: move user accesses in selinuxfs out of locked regions
|
|
If a user is accessing a file in selinuxfs with a pointer to a userspace
buffer that is backed by e.g. a userfaultfd, the userspace access can
stall indefinitely, which can block fsi->mutex if it is held.
For sel_read_policy(), remove the locking, since this method doesn't seem
to access anything that requires locking.
For sel_read_bool(), move the user access below the locked region.
For sel_write_bool() and sel_commit_bools_write(), move the user access
up above the locked region.
Cc: stable@vger.kernel.org
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: removed an unused variable in sel_read_policy()]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Replace printk with pr_* to avoid checkpatch warnings.
Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"Another reasonable chunk of audit changes for v4.18, thirteen patches
in total.
The thirteen patches can mostly be broken down into one of four
categories: general bug fixes, accessor functions for audit state
stored in the task_struct, negative filter matches on executable
names, and extending the (relatively) new seccomp logging knobs to the
audit subsystem.
The main driver for the accessor functions from Richard are the
changes we're working on to associate audit events with containers,
but I think they have some standalone value too so I figured it would
be good to get them in now.
The seccomp/audit patches from Tyler apply the seccomp logging
improvements from a few releases ago to audit's seccomp logging;
starting with this patchset the changes in
/proc/sys/kernel/seccomp/actions_logged should apply to both the
standard kernel logging and audit.
As usual, everything passes the audit-testsuite and it happens to
merge cleanly with your tree"
[ Heh, except it had trivial merge conflicts with the SELinux tree that
also came in from Paul - Linus ]
* tag 'audit-pr-20180605' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: Fix wrong task in comparison of session ID
audit: use existing session info function
audit: normalize loginuid read access
audit: use new audit_context access funciton for seccomp_actions_logged
audit: use inline function to set audit context
audit: use inline function to get audit context
audit: convert sessionid unset to a macro
seccomp: Don't special case audited processes when logging
seccomp: Audit attempts to modify the actions_logged sysctl
seccomp: Configurable separator for the actions_logged string
seccomp: Separate read and write code for actions_logged sysctl
audit: allow not equal op for audit by executable
audit: add syscall information to FEATURE_CHANGE records
|
|
Recognizing that the audit context is an internal audit value, use an
access function to retrieve the audit context pointer for the task
rather than reaching directly into the task struct to get it.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: merge fuzz in auditsc.c and selinuxfs.c, checkpatch.pl fixes]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
The audit MAC_POLICY_LOAD record had redundant dangling keywords and was
missing information about which LSM was responsible and its completion
status. While this record is only issued on success, the parser expects
the res= field to be present.
Old record:
type=MAC_POLICY_LOAD msg=audit(1479299795.404:43): policy loaded auid=0 ses=1
Delete the redundant dangling keywords, add the lsm= field and the res=
field.
New record:
type=MAC_POLICY_LOAD msg=audit(1523293846.204:894): auid=0 ses=1 lsm=selinux res=1
See: https://github.com/linux-audit/audit-kernel/issues/47
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
There were two formats of the audit MAC_STATUS record, one of which was more
standard than the other. One listed enforcing status changes and the
other listed enabled status changes with a non-standard label. In
addition, the record was missing information about which LSM was
responsible and the operation's completion status. While this record is
only issued on success, the parser expects the res= field to be present.
old enforcing/permissive:
type=MAC_STATUS msg=audit(1523312831.378:24514): enforcing=0 old_enforcing=1 auid=0 ses=1
old enable/disable:
type=MAC_STATUS msg=audit(1523312831.378:24514): selinux=0 auid=0 ses=1
List both sets of status and old values and add the lsm= field and the
res= field.
Here is the new format:
type=MAC_STATUS msg=audit(1523293828.657:891): enforcing=0 old_enforcing=1 auid=0 ses=1 enabled=1 old-enabled=1 lsm=selinux res=1
This record already accompanied a SYSCALL record.
See: https://github.com/linux-audit/audit-kernel/issues/46
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: 80-char fixes, merge fuzz, use new SELinux state functions]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Use new return type vm_fault_t for fault handler
in struct vm_operations_struct.
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Commit 0619f0f5e36f ("selinux: wrap selinuxfs state") triggers a BUG
when SELinux is runtime-disabled (i.e. systemd or equivalent disables
SELinux before initial policy load via /sys/fs/selinux/disable based on
/etc/selinux/config SELINUX=disabled).
This does not manifest if SELinux is disabled via kernel command line
argument or if SELinux is enabled (permissive or enforcing).
Before:
SELinux: Disabled at runtime.
BUG: Dentry 000000006d77e5c7{i=17,n=null} still in use (1) [unmount of selinuxfs selinuxfs]
After:
SELinux: Disabled at runtime.
Fixes: 0619f0f5e36f ("selinux: wrap selinuxfs state")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Wrap the AVC state within the selinux_state structure and
pass it explicitly to all AVC functions. The AVC private state
is encapsulated in a selinux_avc structure that is referenced
from the selinux_state.
This change should have no effect on SELinux behavior or
APIs (userspace or LSM).
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Move global selinuxfs state to a per-instance structure (selinux_fs_info),
and include a pointer to the selinux_state in this structure.
Pass this selinux_state to all security server operations, thereby
ensuring that each selinuxfs instance presents a view of and acts
as an interface to a particular selinux_state instance.
This change should have no effect on SELinux behavior or APIs
(userspace or LSM). It merely wraps the selinuxfs global state,
links it to a particular selinux_state (currently always the single
global selinux_state) and uses that state for all operations.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Rename is_enforcing() to enforcing_enabled() and
enforcing_set() to set_enforcing().
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Define a selinux state structure (struct selinux_state) for
global SELinux state and pass it explicitly to all security server
functions. The public portion of the structure contains state
that is used throughout the SELinux code, such as the enforcing mode.
The structure also contains a pointer to a selinux_ss structure whose
definition is private to the security server and contains security
server specific state such as the policy database and SID table.
This change should have no effect on SELinux behavior or APIs
(userspace or LSM). It merely wraps SELinux state and passes it
explicitly as needed.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: minor fixups needed due to collisions with the SCTP patches]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull memdup_user() conversions from Al Viro:
"A fairly self-contained series - hunting down open-coded memdup_user()
and memdup_user_nul() instances"
* 'work.memdup_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
bpf: don't open-code memdup_user()
kimage_file_prepare_segments(): don't open-code memdup_user()
ethtool: don't open-code memdup_user()
do_ip_setsockopt(): don't open-code memdup_user()
do_ipv6_setsockopt(): don't open-code memdup_user()
irda: don't open-code memdup_user()
xfrm_user_policy(): don't open-code memdup_user()
ima_write_policy(): don't open-code memdup_user_nul()
sel_write_validatetrans(): don't open-code memdup_user_nul()
|
|
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
Add a generic notificaiton mechanism in the LSM. Interested consumers
can register a callback with the LSM and security modules can produce
events.
Because access to Infiniband QPs are enforced in the setup phase of a
connection security should be enforced again if the policy changes.
Register infiniband devices for policy change notification and check all
QPs on that device when the notification is received.
Add a call to the notification mechanism from SELinux when the AVC
cache changes or setenforce is cleared.
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Log the state of SELinux policy capabilities when a policy is loaded.
For each policy capability known to the kernel, log the policy capability
name and the value set in the policy. For policy capabilities that are
set in the loaded policy but unknown to the kernel, log the policy
capability index, since this is the only information presently available
in the policy.
Sample output with a policy created with a new capability defined
that is not known to the kernel:
SELinux: policy capability network_peer_controls=1
SELinux: policy capability open_perms=1
SELinux: policy capability extended_socket_class=1
SELinux: policy capability always_check_network=0
SELinux: policy capability cgroup_seclabel=0
SELinux: unknown policy capability 5
Resolves: https://github.com/SELinuxProject/selinux-kernel/issues/32
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
