Commit graph

7,124 commits

Author SHA1 Message Date
John Johansen
e16eee7895 apparmor: guard against free routines being called with a NULL
aa_free_data() and free_attachment() don't guard against having
a NULL parameter passed to them. Fix this.

Reviewed-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-29 01:27:54 -08:00
Ryan Lee
74b7105e53 apparmor: return -ENOMEM in unpack_perms_table upon alloc failure
In policy_unpack.c:unpack_perms_table, the perms struct is allocated via
kcalloc, with the position being reset if the allocation fails. However,
the error path results in -EPROTO being retured instead of -ENOMEM. Fix
this to return the correct error code.

Reported-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Fixes: fd1b2b95a2 ("apparmor: add the ability for policy to specify a permission table")
Reviewed-by: Tyler Hicks <code@tyhicks.com>
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-29 01:27:54 -08:00
Ryan Lee
9b829c0aa9 apparmor: account for in_atomic removal in common_file_perm
If we are not in an atomic context in common_file_perm, then we don't have
to use the atomic versions, resulting in improved performance outside of
atomic contexts.

Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-29 01:27:54 -08:00
John Johansen
c3f27ccdb2 apparmor: drop in_atomic flag in common_mmap, and common_file_perm
with the previous changes to mmap the in_atomic flag is now always
false, so drop it.

Suggested-by: Tyler Hicks <code@tyhicks.com>
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-29 01:27:53 -08:00
Ryan Lee
48d5268e91 apparmor: fix boolean argument in apparmor_mmap_file
The previous value of GFP_ATOMIC is an int and not a bool, potentially
resulting in UB when being assigned to a bool. In addition, the mmap hook
is called outside of locks (i.e. in a non-atomic context), so we can pass
a fixed constant value of false instead to common_mmap.

Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-29 01:27:53 -08:00
Maxime Bélair
8d34e16f7f apparmor: userns: Add support for execpath in userns
This new field allows reliable identification of the binary that
triggered a denial since the existing field (comm) only gives the name of
the binary, not its path. Thus comm doesn't work for binaries outside of
$PATH or works unreliably when two binaries have the same name.
Additionally comm can be modified by a program, for example, comm="(tor)"
or comm=4143504920506F6C6C6572 (= ACPI Poller).

Signed-off-by: Maxime Bélair <maxime.belair@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-29 01:27:53 -08:00
John Johansen
3d28e2397a apparmor: add support loading per permission tagging
Add support for the per permission tag index for a given permission
set. This will be used by both meta-data tagging, to allow annotating
accept states with context and debug information. As well as by rule
tainting and triggers to specify the taint or trigger to be applied.

Since these are low frequency ancillary data items they are stored
in a tighter packed format to that allows for sharing and reuse of the
strings between permissions and accept states. Reducing the amount of
kernel memory use at the cost of having to go through a couple if
index based indirections.

The tags are just strings that has no meaning with out context. When
used as meta-data for auditing and debugging its entirely information
for userspace, but triggers, and tainting can be used to affect the
domain. However they all exist in the same packed data set and can
be shared between different uses.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-29 01:27:47 -08:00
Marco Elver
41539433b3 tomoyo: Use scoped init guard
Convert lock initialization to scoped guarded initialization where
lock-guarded members are initialized in the same scope.

This ensures the context analysis treats the context as active during member
initialization. This is required to avoid errors once implicit context
assertion is removed.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260119094029.1344361-6-elver@google.com
2026-01-28 20:45:25 +01:00
Harshit Mogalapalli
10d1c75ed4 ima: verify the previous kernel's IMA buffer lies in addressable RAM
Patch series "Address page fault in ima_restore_measurement_list()", v3.

When the second-stage kernel is booted via kexec with a limiting command
line such as "mem=<size>" we observe a pafe fault that happens.

    BUG: unable to handle page fault for address: ffff97793ff47000
    RIP: ima_restore_measurement_list+0xdc/0x45a
    #PF: error_code(0x0000)  not-present page

This happens on x86_64 only, as this is already fixed in aarch64 in
commit: cbf9c4b961 ("of: check previous kernel's ima-kexec-buffer
against memory bounds")


This patch (of 3):

When the second-stage kernel is booted with a limiting command line (e.g. 
"mem=<size>"), the IMA measurement buffer handed over from the previous
kernel may fall outside the addressable RAM of the new kernel.  Accessing
such a buffer can fault during early restore.

Introduce a small generic helper, ima_validate_range(), which verifies
that a physical [start, end] range for the previous-kernel IMA buffer lies
within addressable memory:
	- On x86, use pfn_range_is_mapped().
	- On OF based architectures, use page_is_ram().

Link: https://lkml.kernel.org/r/20251231061609.907170-1-harshit.m.mogalapalli@oracle.com
Link: https://lkml.kernel.org/r/20251231061609.907170-2-harshit.m.mogalapalli@oracle.com
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: guoweikang <guoweikang.kernel@gmail.com>
Cc: Henry Willard <henry.willard@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Bohac <jbohac@suse.cz>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: Jonathan McDowell <noodles@fb.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Paul Webb <paul.x.webb@oracle.com>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Yifei Liu <yifei.l.liu@oracle.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26 19:07:10 -08:00
Srish Srinivasan
6342969daf keys/trusted_keys: fix handle passed to tpm_buf_append_name during unseal
TPM2_Unseal[1] expects the handle of a loaded data object, and not the
handle of the parent key. But the tpm2_unseal_cmd provides the parent
keyhandle instead of blob_handle for the session HMAC calculation. This
causes unseal to fail.

Fix this by passing blob_handle to tpm_buf_append_name().

References:

[1] trustedcomputinggroup.org/wp-content/uploads/
    Trusted-Platform-Module-2.0-Library-Part-3-Version-184_pub.pdf

Fixes: 6e9722e9a7 ("tpm2-sessions: Fix out of range indexing in name_size")
Signed-off-by: Srish Srinivasan <ssrish@linux.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2026-01-25 19:03:45 +02:00
Roberto Sassu
0496fc9cdc evm: Use ordered xattrs list to calculate HMAC in evm_init_hmac()
Commit 8e5d9f916a ("smack: deduplicate xattr setting in
smack_inode_init_security()") introduced xattr_dupval() to simplify setting
the xattrs to be provided by the SMACK LSM on inode creation, in the
smack_inode_init_security().

Unfortunately, moving lsm_get_xattr_slot() caused the SMACK64TRANSMUTE
xattr be added in the array of new xattrs before SMACK64. This causes the
HMAC of xattrs calculated by evm_init_hmac() for new files to diverge from
the one calculated by both evm_calc_hmac_or_hash() and evmctl.

evm_init_hmac() calculates the HMAC of the xattrs of new files based on the
order LSMs provide them, while evm_calc_hmac_or_hash() and evmctl calculate
the HMAC based on an ordered xattrs list.

Fix the issue by making evm_init_hmac() calculate the HMAC of new files
based on the ordered xattrs list too.

Fixes: 8e5d9f916a ("smack: deduplicate xattr setting in smack_inode_init_security()")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2026-01-23 14:31:41 -05:00
John Johansen
c140dcd124 apparmor: make str table more generic and be able to have multiple entries
The strtable is currently limited to a single entry string on unpack
even though domain has the concept of multiple entries within it. Make
this a reality as it will be used for tags and more advanced domain
transitions.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-22 04:56:39 -08:00
Helge Deller
6fc367bfd4 apparmor: Fix & Optimize table creation from possibly unaligned memory
Source blob may come from userspace and might be unaligned.
Try to optize the copying process by avoiding unaligned memory accesses.

- Added Fixes tag
- Added "Fix &" to description as this doesn't just optimize but fixes
        a potential unaligned memory access
Fixes: e6e8bf4188 ("apparmor: fix restricted endian type warnings for dfa unpack")
Signed-off-by: Helge Deller <deller@gmx.de>
[jj: remove duplicate word "convert" in comment trigger checkpatch warning]
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-22 04:52:25 -08:00
Helge Deller
64802f7312 AppArmor: Allow apparmor to handle unaligned dfa tables
The dfa tables can originate from kernel or userspace and 8-byte alignment
isn't always guaranteed and as such may trigger unaligned memory accesses
on various architectures. Resulting in the following

[   73.901376] WARNING: CPU: 0 PID: 341 at security/apparmor/match.c:316 aa_dfa_unpack+0x6cc/0x720
[   74.015867] Modules linked in: binfmt_misc evdev flash sg drm drm_panel_orientation_quirks backlight i2c_core configfs nfnetlink autofs4 ext4 crc16 mbcache jbd2 hid_generic usbhid sr_mod hid cdrom
sd_mod ata_generic ohci_pci ehci_pci ehci_hcd ohci_hcd pata_ali libata sym53c8xx scsi_transport_spi tg3 scsi_mod usbcore libphy scsi_common mdio_bus usb_common
[   74.428977] CPU: 0 UID: 0 PID: 341 Comm: apparmor_parser Not tainted 6.18.0-rc6+ #9 NONE
[   74.536543] Call Trace:
[   74.568561] [<0000000000434c24>] dump_stack+0x8/0x18
[   74.633757] [<0000000000476438>] __warn+0xd8/0x100
[   74.696664] [<00000000004296d4>] warn_slowpath_fmt+0x34/0x74
[   74.771006] [<00000000008db28c>] aa_dfa_unpack+0x6cc/0x720
[   74.843062] [<00000000008e643c>] unpack_pdb+0xbc/0x7e0
[   74.910545] [<00000000008e7740>] unpack_profile+0xbe0/0x1300
[   74.984888] [<00000000008e82e0>] aa_unpack+0xe0/0x6a0
[   75.051226] [<00000000008e3ec4>] aa_replace_profiles+0x64/0x1160
[   75.130144] [<00000000008d4d90>] policy_update+0xf0/0x280
[   75.201057] [<00000000008d4fc8>] profile_replace+0xa8/0x100
[   75.274258] [<0000000000766bd0>] vfs_write+0x90/0x420
[   75.340594] [<00000000007670cc>] ksys_write+0x4c/0xe0
[   75.406932] [<0000000000767174>] sys_write+0x14/0x40
[   75.472126] [<0000000000406174>] linux_sparc_syscall+0x34/0x44
[   75.548802] ---[ end trace 0000000000000000 ]---
[   75.609503] dfa blob stream 0xfff0000008926b96 not aligned.
[   75.682695] Kernel unaligned access at TPC[8db2a8] aa_dfa_unpack+0x6e8/0x720

Work around it by using the get_unaligned_xx() helpers.

Fixes: e6e8bf4188 ("apparmor: fix restricted endian type warnings for dfa unpack")
Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Closes: https://github.com/sparclinux/issues/issues/30
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-22 04:52:25 -08:00
Thorsten Blum
1c90ed1f14 apparmor: Replace deprecated strcpy with memcpy in gen_symlink_name
strcpy() is deprecated; use memcpy() instead. Unlike strcpy(), memcpy()
does not copy the NUL terminator from the source string, which would be
overwritten anyway on every iteration when using strcpy(). snprintf()
then ensures that 'char *s' is NUL-terminated.

Replace the hard-coded path length to remove the magic number 6, and add
a comment explaining the extra 11 bytes.

Closes: https://github.com/KSPP/linux/issues/88
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-22 04:52:25 -08:00
John Johansen
00b6765753 apparmor: fix NULL sock in aa_sock_file_perm
Deal with the potential that sock and sock-sk can be NULL during
socket setup or teardown. This could lead to an oops. The fix for NULL
pointer dereference in __unix_needs_revalidation shows this is at
least possible for af_unix sockets. While the fix for af_unix sockets
applies for newer mediation this is still the fall back path for older
af_unix mediation and other sockets, so ensure it is covered.

Fixes: 56974a6fcf ("apparmor: add base infastructure for socket mediation")
Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-22 04:51:55 -08:00
Randy Dunlap
24c776355f kernel.h: drop hex.h and update all hex.h users
Remove <linux/hex.h> from <linux/kernel.h> and update all users/callers of
hex.h interfaces to directly #include <linux/hex.h> as part of the process
of putting kernel.h on a diet.

Removing hex.h from kernel.h means that 36K C source files don't have to
pay the price of parsing hex.h for the roughly 120 C source files that
need it.

This change has been build-tested with allmodconfig on most ARCHes.  Also,
all users/callers of <linux/hex.h> in the entire source tree have been
updated if needed (if not already #included).

Link: https://lkml.kernel.org/r/20251215005206.2362276-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20 19:44:19 -08:00
Linus Torvalds
90a855e75a Landlock fix for v6.19-rc6
-----BEGIN PGP SIGNATURE-----
 
 iIYEABYKAC4WIQSVyBthFV4iTW/VU1/l49DojIL20gUCaWledRAcbWljQGRpZ2lr
 b2QubmV0AAoJEOXj0OiMgvbSBowBAID4pRQB8EKRNaoqadUWnoSE/wl929Y6KY7i
 FBf8aODOAP9lOtU/CjL5jHKjt00zKW5gX3o0LIuFzSeuzCFTVx2MBA==
 =Aef0
 -----END PGP SIGNATURE-----

Merge tag 'landlock-6.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux

Pull landlock fixes from Mickaël Salaün:
 "This fixes TCP handling, tests, documentation, non-audit elided code,
  and minor cosmetic changes"

* tag 'landlock-6.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux:
  landlock: Clarify documentation for the IOCTL access right
  selftests/landlock: Properly close a file descriptor
  landlock: Improve the comment for domain_is_scoped
  selftests/landlock: Use scoped_base_variants.h for ptrace_test
  selftests/landlock: Fix missing semicolon
  selftests/landlock: Fix typo in fs_test
  landlock: Optimize stack usage when !CONFIG_AUDIT
  landlock: Fix spelling
  landlock: Clean up hook_ptrace_access_check()
  landlock: Improve erratum documentation
  landlock: Remove useless include
  landlock: Fix wrong type usage
  selftests/landlock: NULL-terminate unix pathname addresses
  selftests/landlock: Remove invalid unix socket bind()
  selftests/landlock: Add missing connect(minimal AF_UNSPEC) test
  selftests/landlock: Fix TCP bind(AF_UNSPEC) test case
  landlock: Fix TCP handling of short AF_UNSPEC addresses
  landlock: Fix formatting
2026-01-18 15:15:47 -08:00
System Administrator
e2938ad00b apparmor: fix NULL pointer dereference in __unix_needs_revalidation
When receiving file descriptors via SCM_RIGHTS, both the socket pointer
and the socket's sk pointer can be NULL during socket setup or teardown,
causing NULL pointer dereferences in __unix_needs_revalidation().

This is a regression in AppArmor 5.0.0 (kernel 6.17+) where the new
__unix_needs_revalidation() function was added without proper NULL checks.

The crash manifests as:
  BUG: kernel NULL pointer dereference, address: 0x0000000000000018
  RIP: aa_file_perm+0xb7/0x3b0 (or +0xbe/0x3b0, +0xc0/0x3e0)
  Call Trace:
   apparmor_file_receive+0x42/0x80
   security_file_receive+0x2e/0x50
   receive_fd+0x1d/0xf0
   scm_detach_fds+0xad/0x1c0

The function dereferences sock->sk->sk_family without checking if either
sock or sock->sk is NULL first.

Add NULL checks for both sock and sock->sk before accessing sk_family.

Fixes: 88fec3526e ("apparmor: make sure unix socket labeling is correctly updated.")
Reported-by: Jamin Mc <jaminmc@gmail.com>
Closes: https://bugzilla.proxmox.com/show_bug.cgi?id=7083
Closes: https://gitlab.com/apparmor/apparmor/-/issues/568
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Signed-off-by: System Administrator <root@localhost>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-18 07:06:30 -08:00
Thorsten Blum
93d4dbdc8d apparmor: Replace deprecated strcpy in d_namespace_path
strcpy() is deprecated; replace it with a direct '/' assignment. The
buffer is already NUL-terminated, so there is no need to copy an
additional NUL terminator as strcpy() did.

Update the comment and add the local variable 'is_root' for clarity.

Closes: https://github.com/KSPP/linux/issues/88
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-18 06:53:18 -08:00
Thorsten Blum
b31d3f7385 apparmor: Replace sprintf/strcpy with scnprintf/strscpy in aa_policy_init
strcpy() is deprecated and sprintf() does not perform bounds checking
either. Although an overflow is unlikely, it's better to proactively
avoid it by using the safer strscpy() and scnprintf(), respectively.

Additionally, unify memory allocation for 'hname' to simplify and
improve aa_policy_init().

Closes: https://github.com/KSPP/linux/issues/88
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-18 06:52:58 -08:00
Thorsten Blum
7db8c3c738 apparmor: replace sprintf with snprintf in aa_new_learning_profile
Replace unbounded sprintf() calls with snprintf() to prevent potential
buffer overflows in aa_new_learning_profile(). While the current code
works correctly, snprintf() is safer and follows secure coding best
practices.  No functional changes.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-01-16 10:46:54 -08:00
Paul Moore
ea64aa57d5 selinux: drop the BUG() in cred_has_capability()
With the compile time check located immediately above the
cred_has_capability() function ensuring that we will notice if the
capability set grows beyond 63 capabilities, we can safely remove
the BUG() call from the cred_has_capability().

Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-01-14 16:26:21 -05:00
Paul Moore
b07b6f0c5d selinux: fix a capabilities parsing typo in selinux_bpf_token_capable()
There was a typo, likely a cut-n-paste bug, where we were checking for
SECCLASS_CAPABILITY instead of SECCLASS_CAPABILITY2.

Fixes: 5473a722f7 ("selinux: add support for BPF token access control")
Reported-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-01-14 16:15:09 -05:00
Eric Suen
5473a722f7 selinux: add support for BPF token access control
BPF token support was introduced to allow a privileged process to delegate
limited BPF functionality—such as map creation and program loading—to
an unprivileged process:
  https://lore.kernel.org/linux-security-module/20231130185229.2688956-1-andrii@kernel.org/

This patch adds SELinux support for controlling BPF token access. With
this change, SELinux policies can now enforce constraints on BPF token
usage based on both the delegating (privileged) process and the recipient
(unprivileged) process.

Supported operations currently include:
  - map_create
  - prog_load

High-level workflow:
  1. An unprivileged process creates a VFS context via `fsopen()` and
     obtains a file descriptor.
  2. This descriptor is passed to a privileged process, which configures
     BPF token delegation options and mounts a BPF filesystem.
  3. SELinux records the `creator_sid` of the privileged process during
     mount setup.
  4. The unprivileged process then uses this BPF fs mount to create a
     token and attach it to subsequent BPF syscalls.
  5. During verification of `map_create` and `prog_load`, SELinux uses
     `creator_sid` and the current SID to check policy permissions via:
       avc_has_perm(creator_sid, current_sid, SECCLASS_BPF,
                    BPF__MAP_CREATE, NULL);

The implementation introduces two new permissions:
  - map_create_as
  - prog_load_as

At token creation time, SELinux verifies that the current process has the
appropriate `*_as` permission (depending on the `allowed_cmds` value in
the bpf_token) to act on behalf of the `creator_sid`.

Example SELinux policy:
  allow test_bpf_t self:bpf {
      map_create map_read map_write prog_load prog_run
      map_create_as prog_load_as
  };

Additionally, a new policy capability bpf_token_perms is added to ensure
backward compatibility. If disabled, previous behavior ((checks based on
current process SID)) is preserved.

Signed-off-by: Eric Suen <ericsu@linux.microsoft.com>
Tested-by: Daniel Durning <danieldurning.work@gmail.com>
Reviewed-by: Daniel Durning <danieldurning.work@gmail.com>
[PM: merge fuzz, subject tweaks, whitespace tweaks, line length tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-01-13 15:42:37 -05:00
Paul Moore
27a7cef9c3 selinux: move the selinux_blob_sizes struct
Move the selinux_blob_sizes struct so it adjacent to the rest of the
SELinux initialization code and not in the middle of the LSM hook
callbacks.

Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-01-13 11:53:38 -05:00
Ryan Foster
24e9b431b5
security: Add KUnit tests for kuid_root_in_ns and vfsuid_root_in_currentns
Add comprehensive KUnit tests for the namespace-related capability
functions that Serge Hallyn refactored in commit 9891d2f79a
("Clarify the rootid_owns_currentns").

The tests verify:
- Basic functionality: UID 0 in init namespace, invalid vfsuid,
  non-zero UIDs
- Actual namespace traversal: Creating user namespaces with different
  UID mappings where uid 0 maps to different kuids (e.g., 1000, 2000,
  3000)
- Hierarchy traversal: Testing multiple nested namespaces to verify
  correct namespace hierarchy traversal

This addresses the feedback to "test the actual functionality" by
creating real user namespaces with different values for the
namespace's uid 0, rather than just basic input validation.

The test file is included at the end of commoncap.c when
CONFIG_SECURITY_COMMONCAP_KUNIT_TEST is enabled, following the
standard kernel pattern (e.g., scsi_lib.c, ext4/mballoc.c). This
allows tests to access static functions in the same compilation unit
without modifying production code based on test configuration.

The tests require CONFIG_USER_NS to be enabled since they rely on user
namespace mapping functionality. The Kconfig dependency ensures the
tests only build when this requirement is met.

All 7 tests pass:
- test_vfsuid_root_in_currentns_init_ns
- test_vfsuid_root_in_currentns_invalid
- test_vfsuid_root_in_currentns_nonzero
- test_kuid_root_in_ns_init_ns_uid0
- test_kuid_root_in_ns_init_ns_nonzero
- test_kuid_root_in_ns_with_mapping
- test_kuid_root_in_ns_with_different_mappings

Updated MAINTAINER capabilities to include commoncap test

Signed-off-by: Ryan Foster <foster.ryan.r@gmail.com>
Signed-off-by: Serge Hallyn <sergeh@kernel.org>
2026-01-09 11:28:28 -06:00
Uwe Kleine-König
c6ef3e9057 KEYS: trusted: Make use of tee bus methods
The tee bus got dedicated callbacks for probe and remove.
Make use of these. This fixes a runtime warning about the driver needing
to be converted to the bus methods.

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2026-01-07 08:14:53 +01:00
Uwe Kleine-König
7b7e532b58 KEYS: trusted: Migrate to use tee specific driver registration function
The tee subsystem recently got a set of dedicated functions to register
(and unregister) a tee driver. Make use of them. These care for setting the
driver's bus (so the explicit assignment can be dropped) and the driver
owner (which is an improvement this driver benefits from).

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2026-01-07 08:14:53 +01:00
Ben Dooks
472711068f lsm: make keys for static branch static
The key use for static-branches are not refrenced by name outside
of the security/security.c file, so make them static. This stops
the sparse warnings about "Should it be static?" such as:

security/security.c: note: in included file:
./include/linux/lsm_hook_defs.h:29:1: warning: symbol
  'security_hook_active_binder_set_context_mgr_0' was not declared.
  Should it be static?
./include/linux/lsm_hook_defs.h:29:1: warning: symbol
  'security_hook_active_binder_set_context_mgr_1' was not declared.
  Should it be static?
...

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
[PM: trimmed sparse output for line-length, readability]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-01-06 20:57:55 -05:00
Marco Elver
87335b61a2 security/tomoyo: Enable context analysis
Enable context analysis for security/tomoyo.

This demonstrates a larger conversion to use Clang's context
analysis. The benefit is additional static checking of locking rules,
along with better documentation.

Tomoyo makes use of several synchronization primitives, yet its clear
design made it relatively straightforward to enable context analysis.

One notable finding was:

  security/tomoyo/gc.c:664:20: error: reading variable 'write_buf' requires holding mutex '&tomoyo_io_buffer::io_sem'
    664 |                 is_write = head->write_buf != NULL;

For which Tetsuo writes:

  "Good catch. This should be data_race(), for tomoyo_write_control()
   might concurrently update head->write_buf from non-NULL to non-NULL
   with head->io_sem held."

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20251219154418.3592607-35-elver@google.com
2026-01-05 16:43:36 +01:00
Joel Granados
a2564d0688 loadpin: Implement custom proc_handler for enforce
Add a new static variable (loadpin_root_writable) to keep the
write-ability state of enforce. Remove set_sysctl and const qualify
loadpin_sysctl_table (moves into .rodata) as there is no longer need to
change the value of extra1. The new proc_handler_loadpin returns -EINVAL
when loadpin_root_writable is false and the kernel var (enforce) is
being written. The old way of modifying the write-ability of enforce
stays in loadpin_check and is still set by calling sb_is_writable.

Signed-off-by: Joel Granados <joel.granados@kernel.org>
2026-01-05 13:45:19 +01:00
Konstantin Andreev
33d589ed60 smack: /smack/doi: accept previously used values
Writing to /smack/doi a value that has ever been
written there in the past disables networking for
non-ambient labels.
E.g.

    # cat /smack/doi
    3
    # netlabelctl -p cipso list
    Configured CIPSO mappings (1)
     DOI value : 3
       mapping type : PASS_THROUGH
    # netlabelctl -p map list
    Configured NetLabel domain mappings (3)
     domain: "_" (IPv4)
       protocol: UNLABELED
     domain: DEFAULT (IPv4)
       protocol: CIPSO, DOI = 3
     domain: DEFAULT (IPv6)
       protocol: UNLABELED

    # cat /smack/ambient
    _
    # cat /proc/$$/attr/smack/current
    _
    # ping -c1 10.1.95.12
    64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.964 ms
    # echo foo >/proc/$$/attr/smack/current
    # ping -c1 10.1.95.12
    64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.956 ms
    unknown option 86

    # echo 4 >/smack/doi
    # echo 3 >/smack/doi
!>  [  214.050395] smk_cipso_doi:691 cipso add rc = -17
    # echo 3 >/smack/doi
!>  [  249.402261] smk_cipso_doi:678 remove rc = -2
!>  [  249.402261] smk_cipso_doi:691 cipso add rc = -17

    # ping -c1 10.1.95.12
!!> ping: 10.1.95.12: Address family for hostname not supported

    # echo _ >/proc/$$/attr/smack/current
    # ping -c1 10.1.95.12
    64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.617 ms

This happens because Smack keeps decommissioned DOIs,
fails to re-add them, and consequently refuses to add
the “default” domain map:

    # netlabelctl -p cipso list
    Configured CIPSO mappings (2)
     DOI value : 3
       mapping type : PASS_THROUGH
     DOI value : 4
       mapping type : PASS_THROUGH
    # netlabelctl -p map list
    Configured NetLabel domain mappings (2)
     domain: "_" (IPv4)
       protocol: UNLABELED
!>  (no ipv4 map for default domain here)
     domain: DEFAULT (IPv6)
       protocol: UNLABELED

Fix by clearing decommissioned DOI definitions and
serializing concurrent DOI updates with a new lock.

Also:
- allow /smack/doi to live unconfigured, since
  adding a map (netlbl_cfg_cipsov4_map_add) may fail.
  CIPSO_V4_DOI_UNKNOWN(0) indicates the unconfigured DOI
- add new DOI before removing the old default map,
  so the old map remains if the add fails

(2008-02-04, Casey Schaufler)
Fixes: e114e47377 ("Smack: Simplified Mandatory Access Control Kernel")

Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2025-12-30 12:17:15 -08:00
Konstantin Andreev
19c013e155 smack: /smack/doi must be > 0
/smack/doi allows writing and keeping negative doi values.
Correct values are 0 < doi <= (max 32-bit positive integer)

(2008-02-04, Casey Schaufler)
Fixes: e114e47377 ("Smack: Simplified Mandatory Access Control Kernel")

Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2025-12-30 12:17:15 -08:00
Taimoor Zaeem
e877cbb453 security: smack: fix indentation in smack_access.c
Replace spaces in code indent with tab character.

Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2025-12-30 12:17:15 -08:00
Tingmao Wang
ef4536f152
landlock: Improve the comment for domain_is_scoped
Currently it is not obvious what "scoped" mean, and the fact that the
function returns true when access should be denied is slightly surprising
and in need of documentation.

Cc: Tahera Fahimi <fahimitahera@gmail.com>
Signed-off-by: Tingmao Wang <m@maowtm.org>
Link: https://lore.kernel.org/r/06393bc18aee5bc278df5ef31c64a05b742ebc10.1766885035.git.m@maowtm.org
[mic: Fix formatting and improve consistency]
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-29 16:19:39 +01:00
Mickaël Salaün
602acfb541
landlock: Optimize stack usage when !CONFIG_AUDIT
Until now, each landlock_request struct were allocated on the stack, even
if not really used, because is_access_to_paths_allowed() unconditionally
modified the passed references.  Even if the changed landlock_request
variables are not used, the compiler is not smart enough to detect this
case.

To avoid this issue, explicitly disable the related code when
CONFIG_AUDIT is not set, which enables elision of log_request_parent*
and associated caller's stack variables thanks to dead code elimination.
This makes it possible to reduce the stack frame by 32 bytes for the
path_link and path_rename hooks, and by 20 bytes for most other
filesystem hooks.

Here is a summary of scripts/stackdelta before and after this change
when CONFIG_AUDIT is disabled:

  current_check_refer_path    560  320  -240
  current_check_access_path   328  184  -144
  hook_file_open              328  184  -144
  is_access_to_paths_allowed  376  360  -16

Also, add extra pointer checks to be more future-proof.

Cc: Günther Noack <gnoack@google.com>
Reported-by: Tingmao Wang <m@maowtm.org>
Closes: https://lore.kernel.org/r/eb86863b-53b0-460b-b223-84dd31d765b9@maowtm.org
Fixes: 2fc80c69df ("landlock: Log file-related denials")
Link: https://lore.kernel.org/r/20251219142302.744917-2-mic@digikod.net
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
[mic: Improve stack usage measurement accuracy with scripts/stackdelta]
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-29 16:19:35 +01:00
Chris J Arges
377cae9851 ima: Fix stack-out-of-bounds in is_bprm_creds_for_exec()
KASAN reported a stack-out-of-bounds access in ima_appraise_measurement
from is_bprm_creds_for_exec:

BUG: KASAN: stack-out-of-bounds in ima_appraise_measurement+0x12dc/0x16a0
 Read of size 1 at addr ffffc9000160f940 by task sudo/550
The buggy address belongs to stack of task sudo/550
and is located at offset 24 in frame:
  ima_appraise_measurement+0x0/0x16a0
This frame has 2 objects:
  [48, 56) 'file'
  [80, 148) 'hash'

This is caused by using container_of on the *file pointer. This offset
calculation is what triggers the stack-out-of-bounds error.

In order to fix this, pass in a bprm_is_check boolean which can be set
depending on how process_measurement is called. If the caller has a
linux_binprm pointer and the function is BPRM_CHECK we can determine
is_check and set it then. Otherwise set it to false.

Fixes: 95b3cdafd7 ("ima: instantiate the bprm_creds_for_exec() hook")

Signed-off-by: Chris J Arges <carges@cloudflare.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2025-12-29 08:28:50 -05:00
Mickaël Salaün
6548fb5218
landlock: Fix spelling
Cc: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20251219193855.825889-4-mic@digikod.net
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-26 20:39:01 +01:00
Mickaël Salaün
aa9877d74c
landlock: Clean up hook_ptrace_access_check()
Make variable's scope minimal in hook_ptrace_access_check().

Cc: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20251219193855.825889-3-mic@digikod.net
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-26 20:39:01 +01:00
Mickaël Salaün
03a0ff99ef
landlock: Improve erratum documentation
Improve description about scoped signal handling.

Reported-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20251219193855.825889-2-mic@digikod.net
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-26 20:39:00 +01:00
Mickaël Salaün
60207df2eb
landlock: Remove useless include
Remove useless audit.h include.

Cc: Günther Noack <gnoack@google.com>
Fixes: 33e65b0d3a ("landlock: Add AUDIT_LANDLOCK_ACCESS and log ptrace denials")
Link: https://lore.kernel.org/r/20251219193855.825889-1-mic@digikod.net
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-26 20:39:00 +01:00
Tingmao Wang
29fbfa46e4
landlock: Fix wrong type usage
I think, based on my best understanding, that this type is likely a typo
(even though in the end both are u16)

Signed-off-by: Tingmao Wang <m@maowtm.org>
Fixes: 2fc80c69df ("landlock: Log file-related denials")
Reviewed-by: Günther Noack <gnoack@google.com>
Link: https://lore.kernel.org/r/7339ad7b47f998affd84ca629a334a71f913616d.1765040503.git.m@maowtm.org
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-26 20:38:59 +01:00
Matthieu Buffet
e4d82cbce2
landlock: Fix TCP handling of short AF_UNSPEC addresses
current_check_access_socket() treats AF_UNSPEC addresses as
AF_INET ones, and only later adds special case handling to
allow connect(AF_UNSPEC), and on IPv4 sockets
bind(AF_UNSPEC+INADDR_ANY).
This would be fine except AF_UNSPEC addresses can be as
short as a bare AF_UNSPEC sa_family_t field, and nothing
more. The AF_INET code path incorrectly enforces a length of
sizeof(struct sockaddr_in) instead.

Move AF_UNSPEC edge case handling up inside the switch-case,
before the address is (potentially incorrectly) treated as
AF_INET.

Fixes: fff69fb03d ("landlock: Support network rules with TCP bind and connect")
Signed-off-by: Matthieu Buffet <matthieu@buffet.re>
Link: https://lore.kernel.org/r/20251027190726.626244-4-matthieu@buffet.re
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-26 20:38:56 +01:00
Mickaël Salaün
552dbf47a8
landlock: Fix formatting
Format with clang-format -i security/landlock/*.[ch]

Cc: Christian Brauner <brauner@kernel.org>
Cc: Günther Noack <gnoack3000@gmail.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Fixes: b4dbfd8653 ("Coccinelle-based conversion to use ->i_state accessors")
Link: https://lore.kernel.org/r/20251219193855.825889-5-mic@digikod.net
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
2025-12-26 20:38:53 +01:00
Pingfan Liu
fe55ea8593 kernel/kexec: change the prototype of kimage_map_segment()
The kexec segment index will be required to extract the corresponding
information for that segment in kimage_map_segment().  Additionally,
kexec_segment already holds the kexec relocation destination address and
size.  Therefore, the prototype of kimage_map_segment() can be changed.

Link: https://lkml.kernel.org/r/20251216014852.8737-1-piliu@redhat.com
Fixes: 07d2490297 ("kexec: enable CMA based contiguous allocation")
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Roberto Sassu <roberto.sassu@huawei.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Steven Chen <chenste@linux.microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-12-23 11:23:13 -08:00
Linus Torvalds
4cfc21494a Trivial optimization.
Davidlohr Bueso (1):
   tomoyo: Use local kmap in tomoyo_dump_page()
 
  security/tomoyo/domain.c |    9 ++-------
  1 file changed, 2 insertions(+), 7 deletions(-)
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Merge tag 'tomoyo-pr-20251212' of git://git.code.sf.net/p/tomoyo/tomoyo

Pull tomoyo update from Tetsuo Handa:
 "Trivial optimization"

* tag 'tomoyo-pr-20251212' of git://git.code.sf.net/p/tomoyo/tomoyo:
  tomoyo: Use local kmap in tomoyo_dump_page()
2025-12-14 15:21:02 +12:00
Linus Torvalds
eee654ca9a Landlock update for v6.19-rc1
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Merge tag 'landlock-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux

Pull landlock updates from Mickaël Salaün:
 "This mainly fixes handling of disconnected directories and adds new
  tests"

* tag 'landlock-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux:
  selftests/landlock: Add disconnected leafs and branch test suites
  selftests/landlock: Add tests for access through disconnected paths
  landlock: Improve variable scope
  landlock: Fix handling of disconnected directories
  selftests/landlock: Fix makefile header list
  landlock: Make docs in cred.h and domain.h visible
  landlock: Minor comments improvements
2025-12-06 09:52:41 -08:00
Linus Torvalds
001eefb503 Hi,
This second pull request for 6.19 is targeted for tpm2-sessions updates.
 
 There's two bug fixes and two more cosmetic tweaks for HMAC protected
 sessions. They provide a baseine for further improvements to be
 implemented during the the course of the release cycle.
 
 BR, Jarkko
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Merge tag 'tpmdd-sessions-next-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd

Pull more tpm updates from Jarkko Sakkinen:
 "This is targeted for tpm2-sessions updates.

  There's two bug fixes and two more cosmetic tweaks for HMAC protected
  sessions. They provide a baseine for further improvements to be
  implemented during the the course of the release cycle"

* tag 'tpmdd-sessions-next-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
  tpm2-sessions: Open code tpm_buf_append_hmac_session()
  tpm2-sessions: Remove 'attributes' parameter from tpm_buf_append_auth
  tpm2-sessions: Fix tpm2_read_public range checks
  tpm2-sessions: Fix out of range indexing in name_size
2025-12-05 20:36:28 -08:00
Linus Torvalds
7cd122b552 Some filesystems use a kinda-sorta controlled dentry refcount leak to pin
dentries of created objects in dcache (and undo it when removing those).
 Reference is grabbed and not released, but it's not actually _stored_
 anywhere.  That works, but it's hard to follow and verify; among other
 things, we have no way to tell _which_ of the increments is intended
 to be an unpaired one.  Worse, on removal we need to decide whether
 the reference had already been dropped, which can be non-trivial if
 that removal is on umount and we need to figure out if this dentry is
 pinned due to e.g. unlink() not done.  Usually that is handled by using
 kill_litter_super() as ->kill_sb(), but there are open-coded special
 cases of the same (consider e.g. /proc/self).
 
 Things get simpler if we introduce a new dentry flag (DCACHE_PERSISTENT)
 marking those "leaked" dentries.  Having it set claims responsibility
 for +1 in refcount.
 
 The end result this series is aiming for:
 
 * get these unbalanced dget() and dput() replaced with new primitives that
   would, in addition to adjusting refcount, set and clear persistency flag.
 * instead of having kill_litter_super() mess with removing the remaining
   "leaked" references (e.g. for all tmpfs files that hadn't been removed
   prior to umount), have the regular shrink_dcache_for_umount() strip
   DCACHE_PERSISTENT of all dentries, dropping the corresponding
   reference if it had been set.  After that kill_litter_super() becomes
   an equivalent of kill_anon_super().
 
 Doing that in a single step is not feasible - it would affect too many places
 in too many filesystems.  It has to be split into a series.
 
 This work has really started early in 2024; quite a few preliminary pieces
 have already gone into mainline.  This chunk is finally getting to the
 meat of that stuff - infrastructure and most of the conversions to it.
 
 Some pieces are still sitting in the local branches, but the bulk of
 that stuff is here.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull persistent dentry infrastructure and conversion from Al Viro:
 "Some filesystems use a kinda-sorta controlled dentry refcount leak to
  pin dentries of created objects in dcache (and undo it when removing
  those). A reference is grabbed and not released, but it's not actually
  _stored_ anywhere.

  That works, but it's hard to follow and verify; among other things, we
  have no way to tell _which_ of the increments is intended to be an
  unpaired one. Worse, on removal we need to decide whether the
  reference had already been dropped, which can be non-trivial if that
  removal is on umount and we need to figure out if this dentry is
  pinned due to e.g. unlink() not done. Usually that is handled by using
  kill_litter_super() as ->kill_sb(), but there are open-coded special
  cases of the same (consider e.g. /proc/self).

  Things get simpler if we introduce a new dentry flag
  (DCACHE_PERSISTENT) marking those "leaked" dentries. Having it set
  claims responsibility for +1 in refcount.

  The end result this series is aiming for:

   - get these unbalanced dget() and dput() replaced with new primitives
     that would, in addition to adjusting refcount, set and clear
     persistency flag.

   - instead of having kill_litter_super() mess with removing the
     remaining "leaked" references (e.g. for all tmpfs files that hadn't
     been removed prior to umount), have the regular
     shrink_dcache_for_umount() strip DCACHE_PERSISTENT of all dentries,
     dropping the corresponding reference if it had been set. After that
     kill_litter_super() becomes an equivalent of kill_anon_super().

  Doing that in a single step is not feasible - it would affect too many
  places in too many filesystems. It has to be split into a series.

  This work has really started early in 2024; quite a few preliminary
  pieces have already gone into mainline. This chunk is finally getting
  to the meat of that stuff - infrastructure and most of the conversions
  to it.

  Some pieces are still sitting in the local branches, but the bulk of
  that stuff is here"

* tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  d_make_discardable(): warn if given a non-persistent dentry
  kill securityfs_recursive_remove()
  convert securityfs
  get rid of kill_litter_super()
  convert rust_binderfs
  convert nfsctl
  convert rpc_pipefs
  convert hypfs
  hypfs: swich hypfs_create_u64() to returning int
  hypfs: switch hypfs_create_str() to returning int
  hypfs: don't pin dentries twice
  convert gadgetfs
  gadgetfs: switch to simple_remove_by_name()
  convert functionfs
  functionfs: switch to simple_remove_by_name()
  functionfs: fix the open/removal races
  functionfs: need to cancel ->reset_work in ->kill_sb()
  functionfs: don't bother with ffs->ref in ffs_data_{opened,closed}()
  functionfs: don't abuse ffs_data_closed() on fs shutdown
  convert selinuxfs
  ...
2025-12-05 14:36:21 -08:00