Commit graph

622 commits

Author SHA1 Message Date
Linus Torvalds
dffb641bea selinux/stable-6.17 PR 20250725
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCgAyFiEES0KozwfymdVUl37v6iDy2pc3iXMFAmiD08EUHHBhdWxAcGF1
 bC1tb29yZS5jb20ACgkQ6iDy2pc3iXOFzRAAwTbLKcFggDs0bG6AfqT5KCQHRtRW
 z/0+kvDZeKzJvmJ4XvNMdW3orC2iIYgGCYJgj8umEXh1BOGIOSd4edpGaUKvJB9Z
 S4py0I3udGjlchInmDBZqW2qGaN0EAl/s0AWBbf6QLYmMV1r9+nb5lH71pVBbEQv
 4Vltg61KkQPc6PuDpk7F+BD7yYKSCqxxWyy7zEJsFMntg4jCyoI2PfRhrHM5xuCE
 RRqctblhCc4nNqzhPvse4Vt9PD+cVQx0Pi7arxvSD8M7mVrFTsUV17OoSKlCcLGh
 1LlFk7heoDNC/UQy7xFg5hsy8GeI6gYYY/Fomu7Ue3SYJL2fqqr7xsbJyCCNg8kC
 S17gRPBxqftzl/2SE76V8y5toIRMtT7b+6aXudtukfFbxtBq09XNflq1G3iR9fTo
 o6f9MGpyWW3t/e8wk2yPYfXNXrLe3yJoxV6lIsDaHejOwGi098ArcahKKuxNzRit
 AikIoqn8GEO+j3/X/4YS1xbdS/HkG7N3t+Rbr2GNO4XsmU6iqZRBkmz5UlCcL8u1
 OTQNjzqqSy/DKAfrPAyqN7wiBVXt5siBPwAXIcPbh9JfAI/kRN7LUxAQeGnUps+o
 kJn2zCV3G4kD2qtCVCQ7VifIYGCMxa1PTYsiwu5S4Wgm1Ducvtsx4r3TVKiCuObC
 bwv/1k9kpkvLy/E=
 =M55j
 -----END PGP SIGNATURE-----

Merge tag 'selinux-pr-20250725' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull selinux updates from Paul Moore:

 - Introduce the concept of a SELinux "neveraudit" type which prevents
   all auditing of the given type/domain.

   Taken by itself, the benefit of marking a SELinux domain with the
   "neveraudit" tag is likely not very interesting, especially given the
   significant overlap with the "dontaudit" tag.

   However, given that the "neveraudit" tag applies to *all* auditing of
   the tagged domain, we can do some fairly interesting optimizations
   when a SELinux domain is marked as both "permissive" and "dontaudit"
   (think of the unconfined_t domain).

   While this pull request includes optimized inode permission and
   getattr hooks, these optimizations require SELinux policy changes,
   therefore the improvements may not be visible on standard downstream
   Linux distos for a period of time.

 - Continue the deprecation process of /sys/fs/selinux/user.

   After removing the associated userspace code in 2020, we marked the
   /sys/fs/selinux/user interface as deprecated in Linux v6.13 with
   pr_warn() and the usual documention update.

   This adds a five second sleep after the pr_warn(), following a
   previous deprecation process pattern that has worked well for us in
   the past in helping identify any existing users that we haven't yet
   reached.

 - Add a __GFP_NOWARN flag to our initial hash table allocation.

   Fuzzers such a syzbot often attempt abnormally large SELinux policy
   loads, which the SELinux code gracefully handles by checking for
   allocation failures, but not before the allocator emits a warning
   which causes the automated fuzzing to flag this as an error and
   report it to the list. While we want to continue to support the work
   done by the fuzzing teams, we want to focus on proper issues and not
   an error case that is already handled safely. Add a NOWARN flag to
   quiet the allocator and prevent syzbot from tripping on this again.

 - Remove some unnecessary selinuxfs cleanup code, courtesy of Al.

 - Update the SELinux in-kernel documentation with pointers to
   additional information.

* tag 'selinux-pr-20250725' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: don't bother with selinuxfs_info_free() on failures
  selinux: add __GFP_NOWARN to hashtab_init() allocations
  selinux: optimize selinux_inode_getattr/permission() based on neveraudit|permissive
  selinux: introduce neveraudit types
  documentation: add links to SELinux resources
  selinux: add a 5 second sleep to /sys/fs/selinux/user
2025-07-28 18:25:57 -07:00
Paul Moore
9ab71d9204 selinux: add __GFP_NOWARN to hashtab_init() allocations
As reported by syzbot, hashtab_init() can be affected by abnormally
large policy loads which would cause the kernel's allocator to emit
a warning in some configurations.  Since the SELinux hashtab_init()
code handles the case where the allocation fails, due to a large
request or some other reason, we can safely add the __GFP_NOWARN flag
to squelch these abnormally large allocation warnings.

Reported-by: syzbot+bc2c99c2929c3d219fb3@syzkaller.appspotmail.com
Tested-by: syzbot+bc2c99c2929c3d219fb3@syzkaller.appspotmail.com
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-06-19 17:24:57 -04:00
Stephen Smalley
1106896146 selinux: introduce neveraudit types
Introduce neveraudit types i.e. types that should never trigger
audit messages. This allows the AVC to skip all audit-related
processing for such types. Note that neveraudit differs from
dontaudit not only wrt being applied for all checks with a given
source type but also in that it disables all auditing, not just
permission denials.

When a type is both a permissive type and a neveraudit type,
the security server can short-circuit the security_compute_av()
logic, allowing all permissions and not auditing any permissions.

This change just introduces the basic support but does not yet
further optimize the AVC or hook function logic when a type
is both a permissive type and a dontaudit type.

Suggested-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-06-19 17:23:04 -04:00
Stephen Smalley
fde46f60f6 selinux: change security_compute_sid to return the ssid or tsid on match
If the end result of a security_compute_sid() computation matches the
ssid or tsid, return that SID rather than looking it up again. This
avoids the problem of multiple initial SIDs that map to the same
context.

Cc: stable@vger.kernel.org
Reported-by: Guido Trentalancia <guido@trentalancia.com>
Fixes: ae254858ce ("selinux: introduce an initial SID for early boot processes")
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Tested-by: Guido Trentalancia <guido@trentalancia.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-06-19 16:13:16 -04:00
Paul Moore
1ec31f14a8 selinux: remove a duplicated include
The "linux/parser.h" header was included twice, we only need it once.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202504121945.Q0GDD0sG-lkp@intel.com/
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-04-12 11:31:46 -04:00
Takaya Saeki
8716451a4e selinux: support wildcard match in genfscon
Currently, genfscon only supports string prefix match to label files.
Thus, labeling numerous dynamic sysfs entries requires many specific
path rules. For example, labeling device paths such as
`/sys/devices/pci0000:00/0000:00:03.1/<...>/0000:04:00.1/wakeup`
requires listing all specific PCI paths, which is challenging to
maintain. While user-space restorecon can handle these paths with
regular expression rules, relabeling thousands of paths under sysfs
after it is mounted is inefficient compared to using genfscon.

This commit adds wildcard matching to genfscon to make rules more
efficient and expressive. This new behavior is enabled by
genfs_seclabel_wildcard capability. With this capability, genfscon does
wildcard matching instead of prefix matching. When multiple wildcard
rules match against a path, then the longest rule (determined by the
length of the rule string) will be applied. If multiple rules of the
same length match, the first matching rule encountered in the given
genfscon policy will be applied. Users are encouraged to write longer,
more explicit path rules to avoid relying on this behavior.

This change resulted in nice real-world performance improvements. For
example, boot times on test Android devices were reduced by 15%. This
improvement is due to the elimination of the "restorecon -R /sys" step
during boot, which takes more than two seconds in the worst case.

Signed-off-by: Takaya Saeki <takayas@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-04-11 16:36:34 -04:00
Christian Göttsche
47a1a15645 selinux: constify network address pointer
The network address, either an IPv4 or IPv6 one, is not modified.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-04-11 16:29:50 -04:00
Christian Göttsche
a3d3043ef2 selinux: get netif_wildcard policycap from policy instead of cache
Retrieve the netif_wildcard policy capability in security_netif_sid()
from the locked active policy instead of the cached value in
selinux_state.

Fixes: 8af43b61c1 ("selinux: support wildcard network interface names")
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
[PM: /netlabel/netif/ due to a typo in the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-03-17 16:22:04 -04:00
Christian Göttsche
8af43b61c1 selinux: support wildcard network interface names
Add support for wildcard matching of network interface names.  This is
useful for auto-generated interfaces, for example podman creates network
interfaces for containers with the naming scheme podman0, podman1,
podman2, ...

To maintain backward compatibility guard this feature with a new policy
capability 'netif_wildcard'.

Netifcon definitions are compared against in the order given by the
policy, so userspace tools should sort them in a reasonable order.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-03-07 15:11:10 -05:00
Linus Torvalds
690ffcd817 selinux/stable-6.14 PR 20250121
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCAAyFiEES0KozwfymdVUl37v6iDy2pc3iXMFAmeQE9YUHHBhdWxAcGF1
 bC1tb29yZS5jb20ACgkQ6iDy2pc3iXO66BAAmmhqw3Cm94u6QOjYTQCNrHpmZVpv
 atPfW0EIlvYWuLGvyQZVh/2SKrYm0o7iNlTlOyMcBV9BfFUZd6vepX3L+ylhMacG
 L2lg5jgl11zUZdo8m++38kCABbdMexhTzgtfdAm+w2RmLRoOzXjBOCDx18sWVtCy
 aV3DQAvl6qdU/Y5U6PccmOCwgFVQEmWzQ4A1CMq696Fybr4EzTjI8mCCnotHWarz
 cgfMHHf5RYR4M4VdmxWo3MR6y6Qiq19/Vsy43YP/G/A0Ad+mfLqhHmc27+Mx2bDk
 IfdrvOOjaVxiEeIJe6mOePcW9p1D9q4OrPmBZHxN1+R3ck7k0MgVLIDvSzLDMbbj
 3PSZx2UFk1xz+B0x3hvzhAXJ5YfbAjPj1Z65HlLIQBFBo5jvLWMrLxdpcH4eRdhT
 ovTqFuB4wQwYOeeKlXlnCWFitsAynjo9qGxcqjxG63geJfnBlsnLoYIa0g+cN6Uf
 3Ty0+zeHDfCajj40buvtOWv98CyAMF5vBopnr18Kfo4upp6pgVERVBoGy2Yw020I
 yItiRhi1fpV31J8Gxrd7WA2/OmZZLISnAJtKMSsyd+hBihfOjVZ9LhKKYJk4vH+X
 mWVOdplHpCDe6y2EJE4EmaNwQCOVJfg4/Xvh9fghELdBdc91wFGPDO36AitDBNr8
 /o13aUvFarsEmtA=
 =UJsr
 -----END PGP SIGNATURE-----

Merge tag 'selinux-pr-20250121' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull selinux updates from Paul Moore:

 - Extended permissions supported in conditional policy

   The SELinux extended permissions, aka "xperms", allow security admins
   to target individuals ioctls, and recently netlink messages, with
   their SELinux policy. Adding support for conditional policies allows
   admins to toggle the granular xperms using SELinux booleans, helping
   pave the way for greater use of xperms in general purpose SELinux
   policies. This change bumps the maximum SELinux policy version to 34.

 - Fix a SCTP/SELinux error return code inconsistency

   Depending on the loaded SELinux policy, specifically it's
   EXTSOCKCLASS support, the bind(2) LSM/SELinux hook could return
   different error codes due to the SELinux code checking the socket's
   SELinux object class (which can vary depending on EXTSOCKCLASS) and
   not the socket's sk_protocol field. We fix this by doing the obvious,
   and looking at the sock->sk_protocol field instead of the object
   class.

 - Makefile fixes to properly cleanup av_permissions.h

   Add av_permissions.h to "targets" so that it is properly cleaned up
   using the kbuild infrastructure.

 - A number of smaller improvements by Christian Göttsche

   A variety of straightforward changes to reduce code duplication,
   reduce pointer lookups, migrate void pointers to defined types,
   simplify code, constify function parameters, and correct iterator
   types.

* tag 'selinux-pr-20250121' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: make more use of str_read() when loading the policy
  selinux: avoid unnecessary indirection in struct level_datum
  selinux: use known type instead of void pointer
  selinux: rename comparison functions for clarity
  selinux: rework match_ipv6_addrmask()
  selinux: constify and reconcile function parameter names
  selinux: avoid using types indicating user space interaction
  selinux: supply missing field initializers
  selinux: add netlink nlmsg_type audit message
  selinux: add support for xperms in conditional policies
  selinux: Fix SCTP error inconsistency in selinux_socket_bind()
  selinux: use native iterator types
  selinux: add generated av_permissions.h to targets
2025-01-21 20:09:14 -08:00
Christian Göttsche
01c2253a0f selinux: make more use of str_read() when loading the policy
Simplify the call sites, and enable future string validation in a single
place.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: subject tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-07 23:14:40 -05:00
Christian Göttsche
7491536366 selinux: avoid unnecessary indirection in struct level_datum
Store the owned member of type struct mls_level directly in the parent
struct instead of an extra heap allocation.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-07 23:14:40 -05:00
Christian Göttsche
f07586160f selinux: use known type instead of void pointer
Improve type safety and readability by using the known type.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-07 23:14:39 -05:00
Christian Göttsche
83e7e18eed selinux: rename comparison functions for clarity
The functions context_cmp(), mls_context_cmp() and ebitmap_cmp() are not
traditional C style compare functions returning -1, 0, and 1 for less
than, equal, and greater than; they only return whether their arguments
are equal.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-07 23:14:39 -05:00
Christian Göttsche
5e99b81f48 selinux: rework match_ipv6_addrmask()
Constify parameters, add size hints, and simplify control flow.

According to godbolt the same assembly is generated.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-07 23:14:38 -05:00
Christian Göttsche
9090308510 selinux: constify and reconcile function parameter names
Align the parameter names between declarations and definitions, and
constify read-only parameters.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: tweak the subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-07 23:14:38 -05:00
Christian Göttsche
046b85a993 selinux: avoid using types indicating user space interaction
Integer types starting with a double underscore, like __u32, are
intended for usage of variables interacting with user-space.

Just use the plain variant.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-07 23:14:38 -05:00
Thiébaud Weksteen
5e7f0efd23 selinux: match extended permissions to their base permissions
In commit d1d991efaf ("selinux: Add netlink xperm support") a new
extended permission was added ("nlmsg"). This was the second extended
permission implemented in selinux ("ioctl" being the first one).

Extended permissions are associated with a base permission. It was found
that, in the access vector cache (avc), the extended permission did not
keep track of its base permission. This is an issue for a domain that is
using both extended permissions (i.e., a domain calling ioctl() on a
netlink socket). In this case, the extended permissions were
overlapping.

Keep track of the base permission in the cache. A new field "base_perm"
is added to struct extended_perms_decision to make sure that the
extended permission refers to the correct policy permission. A new field
"base_perms" is added to struct extended_perms to quickly decide if
extended permissions apply.

While it is in theory possible to retrieve the base permission from the
access vector, the same base permission may not be mapped to the same
bit for each class (e.g., "nlmsg" is mapped to a different bit for
"netlink_route_socket" and "netlink_audit_socket"). Instead, use a
constant (AVC_EXT_IOCTL or AVC_EXT_NLMSG) provided by the caller.

Fixes: d1d991efaf ("selinux: Add netlink xperm support")
Signed-off-by: Thiébaud Weksteen <tweek@google.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-01-04 20:58:46 -05:00
Thiébaud Weksteen
900f83cf37 selinux: ignore unknown extended permissions
When evaluating extended permissions, ignore unknown permissions instead
of calling BUG(). This commit ensures that future permissions can be
added without interfering with older kernels.

Cc: stable@vger.kernel.org
Fixes: fa1aa143ac ("selinux: extended permissions for ioctls")
Signed-off-by: Thiébaud Weksteen <tweek@google.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-12-15 21:59:03 -05:00
Christian Göttsche
4aa1761934 selinux: add support for xperms in conditional policies
Add support for extended permission rules in conditional policies.
Currently the kernel accepts such rules already, but evaluating a
security decision will hit a BUG() in
services_compute_xperms_decision().  Thus reject extended permission
rules in conditional policies for current policy versions.

Add a new policy version for this feature.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Tested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-12-13 16:35:38 -05:00
Christian Göttsche
c75c7945cd selinux: use native iterator types
Use types for iterators equal to the type of the to be compared values.

Reported by clang:

    ../ss/sidtab.c:126:2: warning: comparison of integers of different
                          signs: 'int' and 'unsigned long'
      126 |  hash_for_each_rcu(sidtab->context_to_sid, i, entry, list) {
          |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../hashtable.h:139:51: note: expanded from macro 'hash_for_each_rcu'
      139 |  for (... ; obj == NULL && (bkt) < HASH_SIZE(name);\
          |                             ~~~  ^ ~~~~~~~~~~~~~~~

    ../selinuxfs.c:1520:23: warning: comparison of integers of different
                            signs: 'int' and 'unsigned int'
     1520 |  for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
          |                   ~~~ ^ ~~~~~~~~~~

    ../hooks.c:412:16: warning: comparison of integers of different signs:
                       'int' and 'unsigned long'
      412 |  for (i = 0; i < ARRAY_SIZE(tokens); i++) {
          |              ~ ^ ~~~~~~~~~~~~~~~~~~

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: munged the clang output due to line length concerns]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-12-11 13:54:14 -05:00
Linus Torvalds
5591fd5e03 lsm/stable-6.13 PR 20241112
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCAAyFiEES0KozwfymdVUl37v6iDy2pc3iXMFAmcztFcUHHBhdWxAcGF1
 bC1tb29yZS5jb20ACgkQ6iDy2pc3iXPvFQ/+KYwRe3g6gFSu7tRA34okHtUopvpF
 KGAaic06c8oy85gSX4B2Xk4HINCgXVUuRi9Z+0yExRWvvBXRRdQRUj1Vdbj4KOEG
 sRsIA1j1YhPU3wyhkAqwpJ97sQE1v9Xb3xizGwTfQKGQkd+cvtHg0QKM08/jPQYq
 bbbcSxoVsUzh8+idAq1UMfdoTsMh2xeCW7Q1+dbBINJykNzKiqEEc21xgBxeomST
 lSG9XFP3BJr1RBlb4Ux+J8YL+2G/rDBWZh1sR5+t31kgClSgs3CMBRFdTATvplKk
 e9vrcUF8wR7xWWnDmmdobHa462qUt6BWifYarX9RTomGBugZfYDOR/C+jpb+xZwd
 +tZfL6HSOVeBtQ/Zu1bs18eS5i2dj7GxFN7GPY2qXIPvsW5Acwcx1CCK6oNDmX05
 1cOaNuZRYBDye4eAnT3yufnJ34VO80UQIfKTE6dqrX0XtCFYomTxb+Km0qM3utl5
 ubr3Krp6GmVs65lIvtnIhDKSlcNIBbJfH64vdQNnOn/8FvkovGqp2eaX+0wBhROM
 8KgbqntXU4/DgQuDiP01g13mTDeTGdcfyRWKcKMI/CzI/WASPZBpVuqX6xWXh3bs
 NlZmJ/7+Y48Xp2FvaEchQ/A8ppyIrigMLloZ8yAHf2P1z9g6wBNRCrsScdSQVx63
 ArxHLRY44pUOnPs=
 =m/yY
 -----END PGP SIGNATURE-----

Merge tag 'lsm-pr-20241112' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm

Pull lsm updates from Paul Moore:
 "Thirteen patches, all focused on moving away from the current 'secid'
  LSM identifier to a richer 'lsm_prop' structure.

  This move will help reduce the translation that is necessary in many
  LSMs, offering better performance, and make it easier to support
  different LSMs in the future"

* tag 'lsm-pr-20241112' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  lsm: remove lsm_prop scaffolding
  netlabel,smack: use lsm_prop for audit data
  audit: change context data from secid to lsm_prop
  lsm: create new security_cred_getlsmprop LSM hook
  audit: use an lsm_prop in audit_names
  lsm: use lsm_prop in security_inode_getsecid
  lsm: use lsm_prop in security_current_getsecid
  audit: update shutdown LSM data
  lsm: use lsm_prop in security_ipc_getsecid
  audit: maintain an lsm_prop in audit_context
  lsm: add lsmprop_to_secctx hook
  lsm: use lsm_prop in security_audit_rule_match
  lsm: add the lsm_prop data structure
2024-11-18 17:34:05 -08:00
Casey Schaufler
8afd8c8faa lsm: remove lsm_prop scaffolding
Remove the scaffold member from the lsm_prop. Remove the
remaining places it is being set.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: subj line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-10-11 14:34:16 -04:00
Casey Schaufler
870b7fdc66 lsm: use lsm_prop in security_audit_rule_match
Change the secid parameter of security_audit_rule_match
to a lsm_prop structure pointer. Pass the entry from the
lsm_prop structure for the approprite slot to the LSM hook.

Change the users of security_audit_rule_match to use the
lsm_prop instead of a u32. The scaffolding function lsmprop_init()
fills the structure with the value of the old secid, ensuring that
it is available to the appropriate module hook. The sources of
the secid, security_task_getsecid() and security_inode_getsecid(),
will be converted to use the lsm_prop structure later in the series.
At that point the use of lsmprop_init() is dropped.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: subject line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-10-11 14:34:12 -04:00
Thiébaud Weksteen
d1d991efaf selinux: Add netlink xperm support
Reuse the existing extended permissions infrastructure to support
policies based on the netlink message types.

A new policy capability "netlink_xperm" is introduced. When disabled,
the previous behaviour is preserved. That is, netlink_send will rely on
the permission mappings defined in nlmsgtab.c (e.g, nlmsg_read for
RTM_GETADDR on NETLINK_ROUTE). When enabled, the mappings are ignored
and the generic "nlmsg" permission is used instead.

The new "nlmsg" permission is an extended permission. The 16 bits of the
extended permission are mapped to the nlmsg_type field.

Example policy on Android, preventing regular apps from accessing the
device's MAC address and ARP table, but allowing this access to
privileged apps, looks as follows:

allow netdomain self:netlink_route_socket {
	create read getattr write setattr lock append connect getopt
	setopt shutdown nlmsg
};
allowxperm netdomain self:netlink_route_socket nlmsg ~{
	RTM_GETLINK RTM_GETNEIGH RTM_GETNEIGHTBL
};
allowxperm priv_app self:netlink_route_socket nlmsg {
	RTM_GETLINK RTM_GETNEIGH RTM_GETNEIGHTBL
};

The constants in the example above (e.g., RTM_GETLINK) are explicitly
defined in the policy.

It is possible to generate policies to support kernels that may or
may not have the capability enabled by generating a rule for each
scenario. For instance:

allow domain self:netlink_audit_socket nlmsg_read;
allow domain self:netlink_audit_socket nlmsg;
allowxperm domain self:netlink_audit_socket nlmsg { AUDIT_GET };

The approach of defining a new permission ("nlmsg") instead of relying
on the existing permissions (e.g., "nlmsg_read", "nlmsg_readpriv" or
"nlmsg_tty_audit") has been preferred because:
  1. This is similar to the other extended permission ("ioctl");
  2. With the new extended permission, the coarse-grained mapping is not
     necessary anymore. It could eventually be removed, which would be
     impossible if the extended permission was defined below these.
  3. Having a single extra extended permission considerably simplifies
     the implementation here and in libselinux.

Signed-off-by: Thiébaud Weksteen <tweek@google.com>
Signed-off-by: Bram Bonné <brambonne@google.com>
[PM: manual merge fixes for sock_skip_has_perm()]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-10-07 16:28:11 -04:00
Eric Suen
4ad858bd6f selinux: replace kmem_cache_create() with KMEM_CACHE()
Based on guidance in include/linux/slab.h, replace kmem_cache_create()
with KMEM_CACHE() for sources under security/selinux to simplify creation
of SLAB caches.

Signed-off-by: Eric Suen <ericsu@linux.microsoft.com>
[PM: minor grammar nits in the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-08-27 18:42:27 -04:00
Canfeng Guo
da2d41308c selinux: Streamline type determination in security_compute_sid
Simplifies the logic for determining the security context type in
security_compute_sid, enhancing readability and efficiency.

Consolidates default type assignment logic next to type transition
checks, removing redundancy and improving code flow.

Signed-off-by: Canfeng Guo <guocanfeng@uniontech.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-07-29 16:34:00 -04:00
Linus Torvalds
dad8d1a383 selinux/stable-6.11 PR 20240715
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCAAyFiEES0KozwfymdVUl37v6iDy2pc3iXMFAmaVT80UHHBhdWxAcGF1
 bC1tb29yZS5jb20ACgkQ6iDy2pc3iXPyTBAAhRyIqQ33E8XKkUsfcSkOq9jHynVJ
 STXZ5ZKct3KZ4huQRYvUI7t435thaPxz/zPcm9HQesz9gU1BsGzAzQdGcmH1utPh
 /bsR042Q4yxpHLaIPbVNCDrR4DFhjY5i+uLVyegZMYmM94HAlk+yWfrDJ/4w3ZXX
 5iWw1ezxsER4KDuDCX6mrHnfoBh9DbMYhGmMeTy1pAIs14XIIWNmwXtYw1AUTdSe
 Hhyhi0TidUwsLtmWqwBcFW88nka0dpSLiiWWapvTxv7SNp7PMMWLEtGrbpXNpPzl
 t6tjhRe/DFLGEXWbWZSfO0bVvxdMRRbQNWw7iTg2xaom3GNzI0upbehkcLoBrFr5
 +kjwHR7n3f4CBM/kgpPSQqgHcFc0OIJj0WsMUQ131M7RMeadqCzUDxNzwkOfjUy5
 fRexcigzY/PmgLp16/OGEB35DdBSzw3j9FrUkQG0fVTOhSR3tDAWpoYh7GhRVyZV
 eRrQhw/BTeK+ryL3bqVvAUAHmOlGZfYsRS4untqt6wO5GS92C9TT4FOFXRKIvmrI
 3pjyz2atGg/2U42lWUPJPqe8GNj4NbLgfJBJNOz++wvYjQo+e8i/6IQGdigQhDEY
 rJdfwxB7vmH55rEMLVB9swyPi2glAb3F0JDH14UUnGVm5WFKn7UN70T/XkexCno9
 dZotwrPoytUjF6o=
 =+gTM
 -----END PGP SIGNATURE-----

Merge tag 'selinux-pr-20240715' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull selinux update from Paul Moore:
 "A single SELinux patch to change the type of a pre-processor constant
  to better match its use"

* tag 'selinux-pr-20240715' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: Use 1UL for EBITMAP_BIT to match maps type
2024-07-16 14:43:28 -07:00
Canfeng Guo
e123134b39 selinux: Use 1UL for EBITMAP_BIT to match maps type
This patch modifies the definition of EBITMAP_BIT in
security/selinux/ss/ebitmap.h from 1ULL to 1UL to match the type
of elements in the ebitmap_node maps array.

This change does not affect the functionality or correctness of
the code but aims to enhance code quality by adhering to good
programming practices and avoiding unnecessary type conversions.

Signed-off-by: Canfeng Guo <guocanfeng@uniontech.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-07-02 11:41:05 -04:00
GUO Zihua
9a95c5bfbf ima: Avoid blocking in RCU read-side critical section
A panic happens in ima_match_policy:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
PGD 42f873067 P4D 0
Oops: 0000 [#1] SMP NOPTI
CPU: 5 PID: 1286325 Comm: kubeletmonit.sh
Kdump: loaded Tainted: P
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
               BIOS 0.0.0 02/06/2015
RIP: 0010:ima_match_policy+0x84/0x450
Code: 49 89 fc 41 89 cf 31 ed 89 44 24 14 eb 1c 44 39
      7b 18 74 26 41 83 ff 05 74 20 48 8b 1b 48 3b 1d
      f2 b9 f4 00 0f 84 9c 01 00 00 <44> 85 73 10 74 ea
      44 8b 6b 14 41 f6 c5 01 75 d4 41 f6 c5 02 74 0f
RSP: 0018:ff71570009e07a80 EFLAGS: 00010207
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000200
RDX: ffffffffad8dc7c0 RSI: 0000000024924925 RDI: ff3e27850dea2000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffffabfce739
R10: ff3e27810cc42400 R11: 0000000000000000 R12: ff3e2781825ef970
R13: 00000000ff3e2785 R14: 000000000000000c R15: 0000000000000001
FS:  00007f5195b51740(0000)
GS:ff3e278b12d40000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000626d24002 CR4: 0000000000361ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ima_get_action+0x22/0x30
 process_measurement+0xb0/0x830
 ? page_add_file_rmap+0x15/0x170
 ? alloc_set_pte+0x269/0x4c0
 ? prep_new_page+0x81/0x140
 ? simple_xattr_get+0x75/0xa0
 ? selinux_file_open+0x9d/0xf0
 ima_file_check+0x64/0x90
 path_openat+0x571/0x1720
 do_filp_open+0x9b/0x110
 ? page_counter_try_charge+0x57/0xc0
 ? files_cgroup_alloc_fd+0x38/0x60
 ? __alloc_fd+0xd4/0x250
 ? do_sys_open+0x1bd/0x250
 do_sys_open+0x1bd/0x250
 do_syscall_64+0x5d/0x1d0
 entry_SYSCALL_64_after_hwframe+0x65/0xca

Commit c7423dbdbc ("ima: Handle -ESTALE returned by
ima_filter_rule_match()") introduced call to ima_lsm_copy_rule within a
RCU read-side critical section which contains kmalloc with GFP_KERNEL.
This implies a possible sleep and violates limitations of RCU read-side
critical sections on non-PREEMPT systems.

Sleeping within RCU read-side critical section might cause
synchronize_rcu() returning early and break RCU protection, allowing a
UAF to happen.

The root cause of this issue could be described as follows:
|	Thread A	|	Thread B	|
|			|ima_match_policy	|
|			|  rcu_read_lock	|
|ima_lsm_update_rule	|			|
|  synchronize_rcu	|			|
|			|    kmalloc(GFP_KERNEL)|
|			|      sleep		|
==> synchronize_rcu returns early
|  kfree(entry)		|			|
|			|    entry = entry->next|
==> UAF happens and entry now becomes NULL (or could be anything).
|			|    entry->action	|
==> Accessing entry might cause panic.

To fix this issue, we are converting all kmalloc that is called within
RCU read-side critical section to use GFP_ATOMIC.

Fixes: c7423dbdbc ("ima: Handle -ESTALE returned by ima_filter_rule_match()")
Cc: stable@vger.kernel.org
Signed-off-by: GUO Zihua <guozihua@huawei.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: fixed missing comment, long lines, !CONFIG_IMA_LSM_RULES case]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-06-13 14:26:50 -04:00
Christian Göttsche
581646c3fb selinux: constify source policy in cond_policydb_dup()
cond_policydb_dup() duplicates conditional parts of an existing policy.
Declare the source policy const, since it should not be modified.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: various line length fixups]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-04-30 19:01:04 -04:00
Christian Göttsche
851541709a selinux: avoid printk_ratelimit()
The usage of printk_ratelimit() is discouraged, see
include/linux/printk.h, thus use pr_warn_ratelimited().

While editing this line address the following checkpatch warning:

    WARNING: Integer promotion: Using 'h' in '%hu' is unnecessary

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-04-30 19:01:04 -04:00
Ondrej Mosnacek
4e551db042 selinux: clarify return code in filename_trans_read_helper_compat()
For the "conflicting/duplicate rules" branch in
filename_trans_read_helper_compat() the Smatch static checker reports:

    security/selinux/ss/policydb.c:1953 filename_trans_read_helper_compat()
    warn: missing error code 'rc'

While the value of rc will already always be zero here, it is not
obvious that it's the case and that it's the intended return value
(Smatch expects rc to be assigned within 5 lines from the goto).
Therefore, add an explicit assignment just before the goto to make the
intent more clear and the code less error-prone.

Fixes: c3a276111e ("selinux: optimize storage of filename transitions")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/selinux/722b90c4-1f4b-42ff-a6c2-108ea262bd10@moroto.mountain/
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-04-04 16:38:37 -04:00
Christian Göttsche
abb0f43fcd selinux: use u32 as bit position type in ebitmap code
The extensible bitmap supports bit positions up to U32_MAX due to the
type of the member highbit being u32.  Use u32 consistently as the type
for bit positions to announce to callers what range of values is
supported.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: merge fuzz, subject line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-03-27 20:08:55 -04:00
Christian Göttsche
32db469edf selinux: improve symtab string hashing
The number of buckets is calculated by performing a binary AND against
the mask of the hash table, which is one less than its size (which is a
power of two).  This leads to all top bits being discarded, requiring
for short or similar inputs a hash function with a good avalanche
effect.

Use djb2a:

    # current
    common prefixes:  7 entries and 5/8 buckets used, longest chain
                      length 2, sum of chain length^2 11
    classes:  134 entries and 100/256 buckets used, longest chain
              length 5, sum of chain length^2 234
    roles:  15 entries and 6/16 buckets used, longest chain length 5,
            sum of chain length^2 57
    types:  4448 entries and 3016/8192 buckets used, longest chain
            length 41, sum of chain length^2 14922
    users:  7 entries and 3/8 buckets used, longest chain length 3,
            sum of chain length^2 17
    bools:  306 entries and 221/512 buckets used, longest chain
            length 4, sum of chain length^2 524
    levels:  1 entries and 1/1 buckets used, longest chain length 1,
             sum of chain length^2 1
    categories:  1024 entries and 400/1024 buckets used, longest chain
                 length 4, sum of chain length^2 2740

    # patch
    common prefixes:  7 entries and 5/8 buckets used, longest chain
                     length 2, sum of chain length^2 11
    classes:  134 entries and 101/256 buckets used, longest chain
              length 3, sum of chain length^2 210
    roles:  15 entries and 9/16 buckets used, longest chain length 3,
            sum of chain length^2 31
    types:  4448 entries and 3459/8192 buckets used, longest chain
            length 5, sum of chain length^2 6778
    users:  7 entries and 5/8 buckets used, longest chain length 3,
            sum of chain length^2 13
    bools:  306 entries and 236/512 buckets used, longest chain
            length 5, sum of chain length^2 470
    levels:  1 entries and 1/1 buckets used, longest chain length 1,
             sum of chain length^2 1
    categories:  1024 entries and 518/1024 buckets used, longest chain
                 length 7, sum of chain length^2 2992

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: line length fixes in the commit message]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-03-27 19:26:25 -04:00
Christian Göttsche
0fd0b4fefa selinux: dump statistics for more hash tables
Dump in the SELinux debug configuration the statistics for the
conditional rules avtab, the role transition, and class and common
permission hash tables.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: style fixes]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-03-27 19:26:24 -04:00
Christian Göttsche
4b3124de63 selinux: update numeric format specifiers for ebitmaps
Use the correct, according to Documentation/core-api/printk-formats.rst,
format specifiers for numeric arguments in string formatting.
The general bit type is u32 thus use %u, EBITMAP_SIZE is a constant
computed via sizeof() thus use %zu.

Fixes: 0142c56682 ("selinux: reject invalid ebitmaps")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/linux-next/20240327131044.2c629921@canb.auug.org.au/
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-03-27 16:44:35 -04:00
Christian Göttsche
0142c56682 selinux: reject invalid ebitmaps
Reject ebitmaps with a node containing an empty map or with an incorrect
highbit.  Both checks are already performed by userspace, the former
since 2008 (patch 13cd4c896068 ("initial import from svn trunk revision
2950")), the latter since v2.7 in 2017 (patch 75b14a5de10a ("libsepol:
ebitmap: reject loading bitmaps with incorrect high bit")).

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-03-26 16:36:14 -04:00
Paul Moore
a1fc79343a selinux: fix style issues in security/selinux/ss/symtab.c
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>
2024-02-23 17:26:09 -05:00
Paul Moore
5fca473c13 selinux: fix style issues in security/selinux/ss/symtab.h
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>
2024-02-23 17:26:08 -05:00
Paul Moore
dc9a746798 selinux: fix style issues in security/selinux/ss/sidtab.c
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>
2024-02-23 17:26:08 -05:00
Paul Moore
72a1c577d1 selinux: fix style issues in security/selinux/ss/sidtab.h
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>
2024-02-23 17:26:07 -05:00
Paul Moore
317e02905a selinux: fix style issues in security/selinux/ss/services.h
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>
2024-02-23 17:26:07 -05:00
Paul Moore
ec12c6ee2a selinux: fix style issues in security/selinux/ss/policydb.c
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>
2024-02-23 17:26:07 -05:00
Paul Moore
a32582db36 selinux: fix style issues in security/selinux/ss/policydb.h
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>
2024-02-23 17:26:06 -05:00
Paul Moore
793f9add02 selinux: fix style issues in security/selinux/ss/mls_types.h
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>
2024-02-23 17:26:06 -05:00
Paul Moore
4afec3607b selinux: fix style issues in security/selinux/ss/mls.c
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>
2024-02-23 17:26:05 -05:00
Paul Moore
470948bc2d selinux: fix style issues in security/selinux/ss/mls.h
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>
2024-02-23 17:26:05 -05:00
Paul Moore
dfd9bb40a4 selinux: fix style issues in security/selinux/ss/hashtab.c
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>
2024-02-23 17:26:05 -05:00
Paul Moore
a84f5aa628 selinux: fix style issues in security/selinux/ss/hashtab.h
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>
2024-02-23 17:26:04 -05:00