| Age | Commit message (Collapse) | Author |
|---|
|
The shared permissions struct has the stop field which is unneeded
and the "reserved" subtree field commented which is needed. Also
reorganize so that the entries are logically grouped.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Remap xmatch dfa accept table from embedded perms to an index and then
move xmatch lookup to use accept entry to index into the xmatch table.
This is step towards unifying permission lookup and reducing the
size of permissions tables.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Remap file dfa accept table from embedded perms to index and then move
fperm lookup to use the accept entry as an index into the fperm table.
This is a step toward unifying permission lookup.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
continue permission unification by converting xmatch to use the
policydb struct that is used by the other profile dfas.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
file_rules and policydb are almost the same and will need the same
features in the future so combine them.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Rather than computing policydb permissions for each access
permissions can be computed once on profile load and stored for lookup.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Convert xmatch from using perms encoded in the accept entry of the
dfa to the common external aa_perms in a table.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
shorten the name of some of the mapping functions which shortens line
lengths.
change the mapping so it returns the perm table instead of operating
directly on the file struct.
Handle potential memory allocation failure.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
fperm computation is only needed during policy_unpack so move the
code there to isolate it fromt the run time code.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Rather than computing xmatch permissions each time access is requested,
these permissions can be computed once on profile load and stored for
lookup.
Signed-off-by: Mike Salvatore <mike.salvatore@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Rather than computing file permissions for each file access, file
permissions can be computed once on profile load and stored for lookup.
Signed-off-by: Mike Salvatore <mike.salvatore@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Create two new files in apparmor's sysfs:
/sys/kernel/security/apparmor/raw_data_compression_level_min
/sys/kernel/security/apparmor/raw_data_compression_level_max
These correspond to the minimum and maximum zstd compression levels
that can be assigned to the apparmor module parameter
raw_data_compression_level.
Signed-off-by: Jon Tourville <jon.tourville@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Change the algorithm used by apparmor to compress profile data from
zlib to zstd, using the new zstd API introduced in 5.16.
Zstd provides a larger range of compression levels than zlib and
significantly better performance at the default level (for a relatively
small increase in compressed size).
The apparmor module parameter raw_data_compression_level is now clamped
to the minimum and maximum compression levels reported by the zstd
library. A compression level of 0 retains the previous behavior of
disabling policy compression instead of using zstd's behavior, which is
to use the default compression level.
Signed-off-by: Jon Tourville <jon.tourville@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Reserve mediation classes that exist in out of tree development
branches or are used by userspace mediation helpers.
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Fix the following lockdep warning
[ 1119.158984] ============================================
[ 1119.158988] WARNING: possible recursive locking detected
[ 1119.158996] 6.0.0-rc1+ #257 Tainted: G E N
[ 1119.158999] --------------------------------------------
[ 1119.159001] bash/80100 is trying to acquire lock:
[ 1119.159007] ffff88803e79b4a0 (&ns->lock/1){+.+.}-{4:4}, at: destroy_ns.part.0+0x43/0x140
[ 1119.159028]
but task is already holding lock:
[ 1119.159030] ffff8881009764a0 (&ns->lock/1){+.+.}-{4:4}, at: aa_remove_profiles+0x3f0/0x640
[ 1119.159040]
other info that might help us debug this:
[ 1119.159042] Possible unsafe locking scenario:
[ 1119.159043] CPU0
[ 1119.159045] ----
[ 1119.159047] lock(&ns->lock/1);
[ 1119.159051] lock(&ns->lock/1);
[ 1119.159055]
*** DEADLOCK ***
Which is caused by an incorrect lockdep nesting notation
Fixes: feb3c766a3ab ("apparmor: fix possible recursive lock warning in __aa_create_ns")
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
In multi_transaction_new(), the variable t is not freed or passed out
on the failure of copy_from_user(t->data, buf, size), which could lead
to a memleak.
Fix this bug by adding a put_multi_transaction(t) in the error path.
Fixes: 1dea3b41e84c5 ("apparmor: speed up transactional queries")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
|
|
Heap and stack initialization is great, but not when we are trying uses of
uninitialized memory. When the kernel is built with KMSAN, having kernel
memory initialization enabled may introduce false negatives.
We disable CONFIG_INIT_STACK_ALL_PATTERN and CONFIG_INIT_STACK_ALL_ZERO
under CONFIG_KMSAN, making it impossible to auto-initialize stack
variables in KMSAN builds. We also disable
CONFIG_INIT_ON_ALLOC_DEFAULT_ON and CONFIG_INIT_ON_FREE_DEFAULT_ON to
prevent accidental use of heap auto-initialization.
We however still let the users enable heap auto-initialization at
boot-time (by setting init_on_alloc=1 or init_on_free=1), in which case a
warning is printed.
Link: https://lkml.kernel.org/r/20220915150417.722975-31-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Marco Elver <elver@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Daniel Borkmann says:
====================
pull-request: bpf-next 2022-10-03
We've added 143 non-merge commits during the last 27 day(s) which contain
a total of 151 files changed, 8321 insertions(+), 1402 deletions(-).
The main changes are:
1) Add kfuncs for PKCS#7 signature verification from BPF programs, from Roberto Sassu.
2) Add support for struct-based arguments for trampoline based BPF programs,
from Yonghong Song.
3) Fix entry IP for kprobe-multi and trampoline probes under IBT enabled, from Jiri Olsa.
4) Batch of improvements to veristat selftest tool in particular to add CSV output,
a comparison mode for CSV outputs and filtering, from Andrii Nakryiko.
5) Add preparatory changes needed for the BPF core for upcoming BPF HID support,
from Benjamin Tissoires.
6) Support for direct writes to nf_conn's mark field from tc and XDP BPF program
types, from Daniel Xu.
7) Initial batch of documentation improvements for BPF insn set spec, from Dave Thaler.
8) Add a new BPF_MAP_TYPE_USER_RINGBUF map which provides single-user-space-producer /
single-kernel-consumer semantics for BPF ring buffer, from David Vernet.
9) Follow-up fixes to BPF allocator under RT to always use raw spinlock for the BPF
hashtab's bucket lock, from Hou Tao.
10) Allow creating an iterator that loops through only the resources of one
task/thread instead of all, from Kui-Feng Lee.
11) Add support for kptrs in the per-CPU arraymap, from Kumar Kartikeya Dwivedi.
12) Add a new kfunc helper for nf to set src/dst NAT IP/port in a newly allocated CT
entry which is not yet inserted, from Lorenzo Bianconi.
13) Remove invalid recursion check for struct_ops for TCP congestion control BPF
programs, from Martin KaFai Lau.
14) Fix W^X issue with BPF trampoline and BPF dispatcher, from Song Liu.
15) Fix percpu_counter leakage in BPF hashtab allocation error path, from Tetsuo Handa.
16) Various cleanups in BPF selftests to use preferred ASSERT_* macros, from Wang Yufen.
17) Add invocation for cgroup/connect{4,6} BPF programs for ICMP pings, from YiFei Zhu.
18) Lift blinding decision under bpf_jit_harden = 1 to bpf_capable(), from Yauheni Kaliuta.
19) Various libbpf fixes and cleanups including a libbpf NULL pointer deref, from Xin Liu.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (143 commits)
net: netfilter: move bpf_ct_set_nat_info kfunc in nf_nat_bpf.c
Documentation: bpf: Add implementation notes documentations to table of contents
bpf, docs: Delete misformatted table.
selftests/xsk: Fix double free
bpftool: Fix error message of strerror
libbpf: Fix overrun in netlink attribute iteration
selftests/bpf: Fix spelling mistake "unpriviledged" -> "unprivileged"
samples/bpf: Fix typo in xdp_router_ipv4 sample
bpftool: Remove unused struct event_ring_info
bpftool: Remove unused struct btf_attach_point
bpf, docs: Add TOC and fix formatting.
bpf, docs: Add Clang note about BPF_ALU
bpf, docs: Move Clang notes to a separate file
bpf, docs: Linux byteswap note
bpf, docs: Move legacy packet instructions to a separate file
selftests/bpf: Check -EBUSY for the recurred bpf_setsockopt(TCP_CONGESTION)
bpf: tcp: Stop bpf_setsockopt(TCP_CONGESTION) in init ops to recur itself
bpf: Refactor bpf_setsockopt(TCP_CONGESTION) handling into another function
bpf: Move the "cdg" tcp-cc check to the common sol_tcp_sockopt()
bpf: Add __bpf_prog_{enter,exit}_struct_ops for struct_ops trampoline
...
====================
Link: https://lore.kernel.org/r/20221003194915.11847-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
It turns out Apple doesn't capitalise the "mini" in "Macmini" in DMI, which
is inconsistent with other model line names.
Correct the capitalisation of Macmini in the quirk for skipping loading
platform certs on T2 Macs.
Currently users get:
------------[ cut here ]------------
[Firmware Bug]: Page fault caused by firmware at PA: 0xffffa30640054000
WARNING: CPU: 1 PID: 8 at arch/x86/platform/efi/quirks.c:735 efi_crash_gracefully_on_page_fault+0x55/0xe0
Modules linked in:
CPU: 1 PID: 8 Comm: kworker/u12:0 Not tainted 5.18.14-arch1-2-t2 #1 4535eb3fc40fd08edab32a509fbf4c9bc52d111e
Hardware name: Apple Inc. Macmini8,1/Mac-7BA5B2DFE22DDD8C, BIOS 1731.120.10.0.0 (iBridge: 19.16.15071.0.0,0) 04/24/2022
Workqueue: efi_rts_wq efi_call_rts
...
---[ end trace 0000000000000000 ]---
efi: Froze efi_rts_wq and disabled EFI Runtime Services
integrity: Couldn't get size: 0x8000000000000015
integrity: MODSIGN: Couldn't get UEFI db list
efi: EFI Runtime Services are disabled!
integrity: Couldn't get size: 0x8000000000000015
integrity: Couldn't get UEFI dbx list
Fixes: 155ca952c7ca ("efi: Do not import certificates from UEFI Secure Boot for T2 Macs")
Cc: stable@vger.kernel.org
Cc: Aditya Garg <gargaditya08@live.com>
Tested-by: Samuel Jiang <chyishian.jiang@gmail.com>
Signed-off-by: Orlando Chamberlain <redecorating@protonmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
Now that Clang's -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
option is no longer required, remove it from the command line. Clang 16
and later will warn when it is used, which will cause Kconfig to think
it can't use -ftrivial-auto-var-init=zero at all. Check for whether it
is required and only use it when so.
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: linux-kbuild@vger.kernel.org
Cc: llvm@lists.linux.dev
Cc: stable@vger.kernel.org
Fixes: f02003c860d9 ("hardening: Avoid harmless Clang option under CONFIG_INIT_STACK_ALL_ZERO")
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
It seems that all code should use double backquotes, which is also used
to convert "%" defines. Let's use an homogeneous style and remove all
use of simple backquotes (which should only be used for emphasis).
Cc: Günther Noack <gnoack3000@gmail.com>
Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Link: https://lore.kernel.org/r/20220923154207.3311629-4-mic@digikod.net
|
|
Now that we have more than one ABI version, make limitation explanation
more consistent by replacing "ABI 1" with "ABI < 2". This also
indicates which ABIs support such past limitation.
Improve documentation consistency by not using contractions.
Fix spelling in fs.c .
Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20220923154207.3311629-3-mic@digikod.net
|
|
The error injection facility on pseries VMs allows corruption of
arbitrary guest memory, potentially enabling a sufficiently privileged
user to disable lockdown or perform other modifications of the running
kernel via the rtas syscall.
Block the PAPR error injection facility from being opened or called
when locked down.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Acked-by: Paul Moore <paul@paul-moore.com> (LSM)
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926131643.146502-3-nathanl@linux.ibm.com
|
|
The /proc/powerpc/ofdt interface allows the root user to freely alter
the in-kernel device tree, enabling arbitrary physical address writes
via drivers that could bind to malicious device nodes, thus making it
possible to disable lockdown.
Historically this interface has been used on the pseries platform to
facilitate the runtime addition and removal of processor, memory, and
device resources (aka Dynamic Logical Partitioning or DLPAR). Years
ago, the processor and memory use cases were migrated to designs that
happen to be lockdown-friendly: device tree updates are communicated
directly to the kernel from firmware without passing through untrusted
user space. I/O device DLPAR via the "drmgr" command in powerpc-utils
remains the sole legitimate user of /proc/powerpc/ofdt, but it is
already broken in lockdown since it uses /dev/mem to allocate argument
buffers for the rtas syscall. So only illegitimate uses of the
interface should see a behavior change when running on a locked down
kernel.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Acked-by: Paul Moore <paul@paul-moore.com> (LSM)
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926131643.146502-2-nathanl@linux.ibm.com
|
|
These mount option flags are obsolete since commit 12085b14a444 ("smack:
switch to private smack_mnt_opts"), remove them.
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
|
|
Return the value smk_ptrace_rule_check() directly instead of storing it
in another redundant variable.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
|
|
Using smk_of_current() during sk_alloc_security hook leads in
rare cases to a faulty initialization of the security context
of the created socket.
By adding the LSM hook sk_clone_security to SMACK this initialization
fault is corrected by copying the security context of the old socket
pointer to the newly cloned one.
Co-authored-by: Martin Ostertag: <martin.ostertag@elektrobit.com>
Signed-off-by: Lontke Michael <michael.lontke@elektrobit.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
|
|
In preparation for the patch that introduces the bpf_lookup_user_key() eBPF
kfunc, move KEY_LOOKUP_ definitions to include/linux/key.h, to be able to
validate the kfunc parameters. Add them to enum key_lookup_flag, so that
all the current ones and the ones defined in the future are automatically
exported through BTF and available to eBPF programs.
Also, add KEY_LOOKUP_ALL to the enum, with the logical OR of currently
defined flags as value, to facilitate checking whether a variable contains
only those flags.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lore.kernel.org/r/20220920075951.929132-7-roberto.sassu@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
Return the value avc_has_perm() directly instead of storing it in
another redundant variable.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
[PM: subject line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
User space can flood the log with lockdown denial messages:
[ 662.555584] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
[ 662.563237] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
[ 662.571134] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
[ 662.578668] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
[ 662.586021] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
[ 662.593398] Lockdown: bash: debugfs access is restricted; see man kernel_lockdown.7
Ratelimiting these shouldn't meaningfully degrade the quality of the
information logged.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
LoadPin expects the file with trusted verity root digests to be
an ASCII file with one digest (hex value) per line. A pinned
root could contain files that meet these format requirements,
even though the hex values don't represent trusted root
digests.
Add a new requirement to the file format which consists in
the first line containing a fixed string. This prevents
attackers from feeding files with an otherwise valid format
to LoadPin.
Suggested-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220906181725.1.I3f51d1bb0014e5a5951be4ad3c5ad7c7ca1dfc32@changeid
|
|
The doc for CONFIG_SECURITY_LOADPIN_VERITY says that the file with verity
digests must contain a comma separated list of digests. That was the case
at some stage of the development, but was changed during the review
process to one digest per line. Update the Kconfig doc accordingly.
Reported-by: Jae Hoon Kim <kimjae@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Fixes: 3f805f8cc23b ("LoadPin: Enable loading from trusted dm-verity devices")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220829174557.1.I5d202d1344212a3800d9828f936df6511eb2d0d1@changeid
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux
Pull landlock fix from Mickaël Salaün:
"This fixes a mis-handling of the LANDLOCK_ACCESS_FS_REFER right when
multiple rulesets/domains are stacked.
The expected behaviour was that an additional ruleset can only
restrict the set of permitted operations, but in this particular case,
it was potentially possible to re-gain the LANDLOCK_ACCESS_FS_REFER
right"
* tag 'landlock-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux:
landlock: Fix file reparenting without explicit LANDLOCK_ACCESS_FS_REFER
|
|
This change fixes a mis-handling of the LANDLOCK_ACCESS_FS_REFER right
when multiple rulesets/domains are stacked. The expected behaviour was
that an additional ruleset can only restrict the set of permitted
operations, but in this particular case, it was potentially possible to
re-gain the LANDLOCK_ACCESS_FS_REFER right.
With the introduction of LANDLOCK_ACCESS_FS_REFER, we added the first
globally denied-by-default access right. Indeed, this lifted an initial
Landlock limitation to rename and link files, which was initially always
denied when the source or the destination were different directories.
This led to an inconsistent backward compatibility behavior which was
only taken into account if no domain layer were using the new
LANDLOCK_ACCESS_FS_REFER right. However, when restricting a thread with
a new ruleset handling LANDLOCK_ACCESS_FS_REFER, all inherited parent
rulesets/layers not explicitly handling LANDLOCK_ACCESS_FS_REFER would
behave as if they were handling this access right and with all their
rules allowing it. This means that renaming and linking files could
became allowed by these parent layers, but all the other required
accesses must also be granted: all layers must allow file removal or
creation, and renaming and linking operations cannot lead to privilege
escalation according to the Landlock policy. See detailed explanation
in commit b91c3e4ea756 ("landlock: Add support for file reparenting with
LANDLOCK_ACCESS_FS_REFER").
To say it another way, this bug may lift the renaming and linking
limitations of the initial Landlock version, and a same ruleset can
enforce different restrictions depending on previous or next enforced
ruleset (i.e. inconsistent behavior). The LANDLOCK_ACCESS_FS_REFER right
cannot give access to data not already allowed, but this doesn't follow
the contract of the first Landlock ABI. This fix puts back the
limitation for sandboxes that didn't opt-in for this additional right.
For instance, if a first ruleset allows LANDLOCK_ACCESS_FS_MAKE_REG on
/dst and LANDLOCK_ACCESS_FS_REMOVE_FILE on /src, renaming /src/file to
/dst/file is denied. However, without this fix, stacking a new ruleset
which allows LANDLOCK_ACCESS_FS_REFER on / would now permit the
sandboxed thread to rename /src/file to /dst/file .
This change fixes the (absolute) rule access rights, which now always
forbid LANDLOCK_ACCESS_FS_REFER except when it is explicitly allowed
when creating a rule.
Making all domain handle LANDLOCK_ACCESS_FS_REFER was an initial
approach but there is two downsides:
* it makes the code more complex because we still want to check that a
rule allowing LANDLOCK_ACCESS_FS_REFER is legitimate according to the
ruleset's handled access rights (i.e. ABI v1 != ABI v2);
* it would not allow to identify if the user created a ruleset
explicitly handling LANDLOCK_ACCESS_FS_REFER or not, which will be an
issue to audit Landlock.
Instead, this change adds an ACCESS_INITIALLY_DENIED list of
denied-by-default rights, which (only) contains
LANDLOCK_ACCESS_FS_REFER. All domains are treated as if they are also
handling this list, but without modifying their fs_access_masks field.
A side effect is that the errno code returned by rename(2) or link(2)
*may* be changed from EXDEV to EACCES according to the enforced
restrictions. Indeed, we now have the mechanic to identify if an access
is denied because of a required right (e.g. LANDLOCK_ACCESS_FS_MAKE_REG,
LANDLOCK_ACCESS_FS_REMOVE_FILE) or if it is denied because of missing
LANDLOCK_ACCESS_FS_REFER rights. This may result in different errno
codes than for the initial Landlock version, but this approach is more
consistent and better for rename/link compatibility reasons, and it
wasn't possible before (hence no backport to ABI v1). The
layout1.rename_file test reflects this change.
Add 4 layout1.refer_denied_by_default* test suites to check that the
behavior of a ruleset not handling LANDLOCK_ACCESS_FS_REFER (ABI v1) is
unchanged even if another layer handles LANDLOCK_ACCESS_FS_REFER (i.e.
ABI v1 precedence). Make sure rule's absolute access rights are correct
by testing with and without a matching path. Add test_rename() and
test_exchange() helpers.
Extend layout1.inval tests to check that a denied-by-default access
right is not necessarily part of a domain's handled access rights.
Test coverage for security/landlock is 95.3% of 599 lines according to
gcc/gcov-11.
Fixes: b91c3e4ea756 ("landlock: Add support for file reparenting with LANDLOCK_ACCESS_FS_REFER")
Reviewed-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: Günther Noack <gnoack3000@gmail.com>
Link: https://lore.kernel.org/r/20220831203840.1370732-1-mic@digikod.net
Cc: stable@vger.kernel.org
[mic: Constify and slightly simplify test helpers]
Signed-off-by: Mickaël Salaün <mic@digikod.net>
|
|
cast of ->d_name.name to char * is completely wrong - nothing is
allowed to modify its contents.
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm
Pull LSM support for IORING_OP_URING_CMD from Paul Moore:
"Add SELinux and Smack controls to the io_uring IORING_OP_URING_CMD.
These are necessary as without them the IORING_OP_URING_CMD remains
outside the purview of the LSMs (Luis' LSM patch, Casey's Smack patch,
and my SELinux patch). They have been discussed at length with the
io_uring folks, and Jens has given his thumbs-up on the relevant
patches (see the commit descriptions).
There is one patch that is not strictly necessary, but it makes
testing much easier and is very trivial: the /dev/null
IORING_OP_URING_CMD patch."
* tag 'lsm-pr-20220829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
Smack: Provide read control for io_uring_cmd
/dev/null: add IORING_OP_URING_CMD support
selinux: implement the security_uring_cmd() LSM hook
lsm,io_uring: add LSM hooks for the new uring_cmd file op
|
|
The uapi POSIX ACL struct passed through the value argument during
setxattr() contains {g,u}id values encoded via ACL_{GROUP,USER} entries
that should actually be stored in the form of k{g,u}id_t (See [1] for a
long explanation of the issue.).
In 0c5fd887d2bb ("acl: move idmapped mount fixup into vfs_{g,s}etxattr()")
we took the mount's idmapping into account in order to let overlayfs
handle POSIX ACLs on idmapped layers correctly. The fixup is currently
performed directly in vfs_setxattr() which piles on top of the earlier
hackiness by handling the mount's idmapping and stuff the vfs{g,u}id_t
values into the uapi struct as well. While that is all correct and works
fine it's just ugly.
Now that we have introduced vfs_make_posix_acl() earlier move handling
idmapped mounts out of vfs_setxattr() and into the POSIX ACL handler
where it belongs.
Note that we also need to call vfs_make_posix_acl() for EVM which
interpretes POSIX ACLs during security_inode_setxattr(). Leave them a
longer comment for future reference.
All filesystems that support idmapped mounts via FS_ALLOW_IDMAP use the
standard POSIX ACL xattr handlers and are covered by this change. This
includes overlayfs which simply calls vfs_{g,s}etxattr().
The following filesystems use custom POSIX ACL xattr handlers: 9p, cifs,
ecryptfs, and ntfs3 (and overlayfs but we've covered that in the paragraph
above) and none of them support idmapped mounts yet.
Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org/ [1]
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Reviewed-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org>
|
|
Declare ebitmap, mls_level and mls_context parameters const where they
are only read from. This allows callers to supply pointers to const
as arguments and increases readability.
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Do not cast pointers of signed integers to pointers of unsigned integers
and vice versa.
It should currently not be an issue since they hold SELinux boolean
values which should only contain either 0's or 1's, which should have
the same representation.
Reported by sparse:
.../selinuxfs.c:1485:30: warning: incorrect type in assignment
(different signedness)
.../selinuxfs.c:1485:30: expected unsigned int *
.../selinuxfs.c:1485:30: got int *[addressable] values
.../selinuxfs.c:1402:48: warning: incorrect type in argument 3
(different signedness)
.../selinuxfs.c:1402:48: expected int *values
.../selinuxfs.c:1402:48: got unsigned int *bool_pending_values
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: minor whitespace fixes, sparse output cleanup]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Return the value sel_make_perm_files() directly instead of storing it
in another redundant variable.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
[PM: subject line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Limit io_uring "cmd" options to files for which the caller has
Smack read access. There may be cases where the cmd option may
be closer to a write access than a read, but there is no way
to make that determination.
Cc: stable@vger.kernel.org
Fixes: ee692a21e9bf ("fs,io_uring: add infrastructure for uring-cmd")
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Add a SELinux access control for the iouring IORING_OP_URING_CMD
command. This includes the addition of a new permission in the
existing "io_uring" object class: "cmd". The subject of the new
permission check is the domain of the process requesting access, the
object is the open file which points to the device/file that is the
target of the IORING_OP_URING_CMD operation. A sample policy rule
is shown below:
allow <domain> <file>:io_uring { cmd };
Cc: stable@vger.kernel.org
Fixes: ee692a21e9bf ("fs,io_uring: add infrastructure for uring-cmd")
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
io-uring cmd support was added through ee692a21e9bf ("fs,io_uring:
add infrastructure for uring-cmd"), this extended the struct
file_operations to allow a new command which each subsystem can use
to enable command passthrough. Add an LSM specific for the command
passthrough which enables LSMs to inspect the command details.
This was discussed long ago without no clear pointer for something
conclusive, so this enables LSMs to at least reject this new file
operation.
[0] https://lkml.kernel.org/r/8adf55db-7bab-f59d-d612-ed906b948d19@schaufler-ca.com
Cc: stable@vger.kernel.org
Fixes: ee692a21e9bf ("fs,io_uring: add infrastructure for uring-cmd")
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
Limit validating the hash algorithm to just security.ima xattr, not
the security.evm xattr or any of the protected EVM security xattrs,
nor posix acls.
Fixes: 50f742dd9147 ("IMA: block writes of the security.ima xattr with unsupported algorithms")
Reported-by: Christian Brauner <brauner@kernel.org>
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
Idiomatic way to find how much space sprintf output would take is
len = snprintf(NULL, 0, ...) + 1;
Once upon a time there'd been libc implementations that blew chunks
on that and somebody had come up with the following "cute" trick:
len = snprintf((char *) &len, 1, ...) + 1;
for doing the same. However, that's unidiomatic, harder to follow
*and* any such libc implementation would violate both C99 and POSIX
(since 2001).
IOW, this kludge is best buried along with such libc implementations,
nevermind getting cargo-culted into newer code. Our vsnprintf() does not
suffer that braindamage, TYVM.
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening fixes from Kees Cook:
- Also undef LATENT_ENTROPY_PLUGIN for per-file disabling (Andrew
Donnellan)
- Return EFAULT on copy_from_user() failures in LoadPin (Kees Cook)
* tag 'hardening-v6.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
gcc-plugins: Undefine LATENT_ENTROPY_PLUGIN when plugin disabled for a file
LoadPin: Return EFAULT on copy_from_user() failures
|
|
Unprivileged user namespace creation is an intended feature to enable
sandboxing, however this feature is often used to as an initial step to
perform a privilege escalation attack.
This patch implements a new user_namespace { create } access control
permission to restrict which domains allow or deny user namespace
creation. This is necessary for system administrators to quickly protect
their systems while waiting for vulnerability patches to be applied.
This permission can be used in the following way:
allow domA_t domA_t : user_namespace { create };
Signed-off-by: Frederick Lawler <fred@cloudflare.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
User namespaces are an effective tool to allow programs to run with
permission without requiring the need for a program to run as root. User
namespaces may also be used as a sandboxing technique. However, attackers
sometimes leverage user namespaces as an initial attack vector to perform
some exploit. [1,2,3]
While it is not the unprivileged user namespace functionality, which
causes the kernel to be exploitable, users/administrators might want to
more granularly limit or at least monitor how various processes use this
functionality, while vulnerable kernel subsystems are being patched.
Preventing user namespace already creation comes in a few of forms in
order of granularity:
1. /proc/sys/user/max_user_namespaces sysctl
2. Distro specific patch(es)
3. CONFIG_USER_NS
To block a task based on its attributes, the LSM hook cred_prepare is a
decent candidate for use because it provides more granular control, and
it is called before create_user_ns():
cred = prepare_creds()
security_prepare_creds()
call_int_hook(cred_prepare, ...
if (cred)
create_user_ns(cred)
Since security_prepare_creds() is meant for LSMs to copy and prepare
credentials, access control is an unintended use of the hook. [4]
Further, security_prepare_creds() will always return a ENOMEM if the
hook returns any non-zero error code.
This hook also does not handle the clone3 case which requires us to
access a user space pointer to know if we're in the CLONE_NEW_USER
call path which may be subject to a TOCTTOU attack.
Lastly, cred_prepare is called in many call paths, and a targeted hook
further limits the frequency of calls which is a beneficial outcome.
Therefore introduce a new function security_create_user_ns() with an
accompanying userns_create LSM hook.
With the new userns_create hook, users will have more control over the
observability and access control over user namespace creation. Users
should expect that normal operation of user namespaces will behave as
usual, and only be impacted when controls are implemented by users or
administrators.
This hook takes the prepared creds for LSM authors to write policy
against. On success, the new namespace is applied to credentials,
otherwise an error is returned.
Links:
1. https://nvd.nist.gov/vuln/detail/CVE-2022-0492
2. https://nvd.nist.gov/vuln/detail/CVE-2022-25636
3. https://nvd.nist.gov/vuln/detail/CVE-2022-34918
4. https://lore.kernel.org/all/1c4b1c0d-12f6-6e9e-a6a3-cdce7418110c@schaufler-ca.com/
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Frederick Lawler <fred@cloudflare.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
|
|
The copy_from_user() function returns the number of bytes remaining to
be copied on a failure. Such failures should return -EFAULT to high
levels.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 3f805f8cc23b ("LoadPin: Enable loading from trusted dm-verity devices")
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
