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<title>user/sven/linux.git/include/linux/security.h, branch v6.1.4</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.1.4</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.1.4'/>
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<updated>2022-10-09T21:05:15Z</updated>
<entry>
<title>Merge tag 'powerpc-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2022-10-09T21:05:15Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-09T21:05:15Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4899a36f91a9f9b06878471096bd143e7253006d'/>
<id>urn:sha1:4899a36f91a9f9b06878471096bd143e7253006d</id>
<content type='text'>
Pull powerpc updates from Michael Ellerman:

 - Remove our now never-true definitions for pgd_huge() and p4d_leaf().

 - Add pte_needs_flush() and huge_pmd_needs_flush() for 64-bit.

 - Add support for syscall wrappers.

 - Add support for KFENCE on 64-bit.

 - Update 64-bit HV KVM to use the new guest state entry/exit accounting
   API.

 - Support execute-only memory when using the Radix MMU (P9 or later).

 - Implement CONFIG_PARAVIRT_TIME_ACCOUNTING for pseries guests.

 - Updates to our linker script to move more data into read-only
   sections.

 - Allow the VDSO to be randomised on 32-bit.

 - Many other small features and fixes.

Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Christophe Leroy, David Hildenbrand, Disha Goel, Fabiano Rosas,
Gaosheng Cui, Gustavo A. R. Silva, Haren Myneni, Hari Bathini, Jilin
Yuan, Joel Stanley, Kajol Jain, Kees Cook, Krzysztof Kozlowski, Laurent
Dufour, Liang He, Li Huafei, Lukas Bulwahn, Madhavan Srinivasan, Nathan
Chancellor, Nathan Lynch, Nicholas Miehlbradt, Nicholas Piggin, Pali
Rohár, Rohan McLure, Russell Currey, Sachin Sant, Segher Boessenkool,
Shrikanth Hegde, Tyrel Datwyler, Wolfram Sang, ye xingchen, and Zheng
Yongjun.

* tag 'powerpc-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits)
  KVM: PPC: Book3S HV: Fix stack frame regs marker
  powerpc: Don't add __powerpc_ prefix to syscall entry points
  powerpc/64s/interrupt: Fix stack frame regs marker
  powerpc/64: Fix msr_check_and_set/clear MSR[EE] race
  powerpc/64s/interrupt: Change must-hard-mask interrupt check from BUG to WARN
  powerpc/pseries: Add firmware details to the hardware description
  powerpc/powernv: Add opal details to the hardware description
  powerpc: Add device-tree model to the hardware description
  powerpc/64: Add logical PVR to the hardware description
  powerpc: Add PVR &amp; CPU name to hardware description
  powerpc: Add hardware description string
  powerpc/configs: Enable PPC_UV in powernv_defconfig
  powerpc/configs: Update config files for removed/renamed symbols
  powerpc/mm: Fix UBSAN warning reported on hugetlb
  powerpc/mm: Always update max/min_low_pfn in mem_topology_setup()
  powerpc/mm/book3s/hash: Rename flush_tlb_pmd_range
  powerpc: Drops STABS_DEBUG from linker scripts
  powerpc/64s: Remove lost/old comment
  powerpc/64s: Remove old STAB comment
  powerpc: remove orphan systbl_chk.sh
  ...
</content>
</entry>
<entry>
<title>Merge tag 'pull-path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2022-10-07T00:31:02Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-07T00:31:02Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4c0ed7d8d6e3dc013c4599a837de84794baa5b62'/>
<id>urn:sha1:4c0ed7d8d6e3dc013c4599a837de84794baa5b62</id>
<content type='text'>
Pull vfs constification updates from Al Viro:
 "whack-a-mole: constifying struct path *"

* tag 'pull-path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ecryptfs: constify path
  spufs: constify path
  nd_jump_link(): constify path
  audit_init_parent(): constify path
  __io_setxattr(): constify path
  do_proc_readlink(): constify path
  overlayfs: constify path
  fs/notify: constify path
  may_linkat(): constify path
  do_sys_name_to_handle(): constify path
  -&gt;getprocattr(): attribute name is const char *, TYVM...
</content>
</entry>
<entry>
<title>Merge tag 'lsm-pr-20221003' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm</title>
<updated>2022-10-04T00:51:52Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-04T00:51:52Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=26b84401da8458c5cbd6818d5732f7bbb84124a2'/>
<id>urn:sha1:26b84401da8458c5cbd6818d5732f7bbb84124a2</id>
<content type='text'>
Pull LSM updates from Paul Moore:
 "Seven patches for the LSM layer and we've got a mix of trivial and
  significant patches. Highlights below, starting with the smaller bits
  first so they don't get lost in the discussion of the larger items:

   - Remove some redundant NULL pointer checks in the common LSM audit
     code.

   - Ratelimit the lockdown LSM's access denial messages.

     With this change there is a chance that the last visible lockdown
     message on the console is outdated/old, but it does help preserve
     the initial series of lockdown denials that started the denial
     message flood and my gut feeling is that these might be the more
     valuable messages.

   - Open userfaultfds as readonly instead of read/write.

     While this code obviously lives outside the LSM, it does have a
     noticeable impact on the LSMs with Ondrej explaining the situation
     in the commit description. It is worth noting that this patch
     languished on the VFS list for over a year without any comments
     (objections or otherwise) so I took the liberty of pulling it into
     the LSM tree after giving fair notice. It has been in linux-next
     since the end of August without any noticeable problems.

   - Add a LSM hook for user namespace creation, with implementations
     for both the BPF LSM and SELinux.

     Even though the changes are fairly small, this is the bulk of the
     diffstat as we are also including BPF LSM selftests for the new
     hook.

     It's also the most contentious of the changes in this pull request
     with Eric Biederman NACK'ing the LSM hook multiple times during its
     development and discussion upstream. While I've never taken NACK's
     lightly, I'm sending these patches to you because it is my belief
     that they are of good quality, satisfy a long-standing need of
     users and distros, and are in keeping with the existing nature of
     the LSM layer and the Linux Kernel as a whole.

     The patches in implement a LSM hook for user namespace creation
     that allows for a granular approach, configurable at runtime, which
     enables both monitoring and control of user namespaces. The general
     consensus has been that this is far preferable to the other
     solutions that have been adopted downstream including outright
     removal from the kernel, disabling via system wide sysctls, or
     various other out-of-tree mechanisms that users have been forced to
     adopt since we haven't been able to provide them an upstream
     solution for their requests. Eric has been steadfast in his
     objections to this LSM hook, explaining that any restrictions on
     the user namespace could have significant impact on userspace.
     While there is the possibility of impacting userspace, it is
     important to note that this solution only impacts userspace when it
     is requested based on the runtime configuration supplied by the
     distro/admin/user. Frederick (the pathset author), the LSM/security
     community, and myself have tried to work with Eric during
     development of this patchset to find a mutually acceptable
     solution, but Eric's approach and unwillingness to engage in a
     meaningful way have made this impossible. I have CC'd Eric directly
     on this pull request so he has a chance to provide his side of the
     story; there have been no objections outside of Eric's"

* tag 'lsm-pr-20221003' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  lockdown: ratelimit denial messages
  userfaultfd: open userfaultfds with O_RDONLY
  selinux: Implement userns_create hook
  selftests/bpf: Add tests verifying bpf lsm userns_create hook
  bpf-lsm: Make bpf_lsm_userns_create() sleepable
  security, lsm: Introduce security_create_user_ns()
  lsm: clean up redundant NULL pointer check
</content>
</entry>
<entry>
<title>powerpc/rtas: block error injection when locked down</title>
<updated>2022-09-28T09:22:14Z</updated>
<author>
<name>Nathan Lynch</name>
<email>nathanl@linux.ibm.com</email>
</author>
<published>2022-09-26T13:16:43Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b8f3e48834fe8c86b4f21739c6effd160e2c2c19'/>
<id>urn:sha1:b8f3e48834fe8c86b4f21739c6effd160e2c2c19</id>
<content type='text'>
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 &lt;nathanl@linux.ibm.com&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.com&gt; (LSM)
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20220926131643.146502-3-nathanl@linux.ibm.com

</content>
</entry>
<entry>
<title>powerpc/pseries: block untrusted device tree changes when locked down</title>
<updated>2022-09-28T09:22:14Z</updated>
<author>
<name>Nathan Lynch</name>
<email>nathanl@linux.ibm.com</email>
</author>
<published>2022-09-26T13:16:42Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=99df7a2810b6d24651d4887ab61a142e042fb235'/>
<id>urn:sha1:99df7a2810b6d24651d4887ab61a142e042fb235</id>
<content type='text'>
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 &lt;nathanl@linux.ibm.com&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.com&gt; (LSM)
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/20220926131643.146502-2-nathanl@linux.ibm.com

</content>
</entry>
<entry>
<title>-&gt;getprocattr(): attribute name is const char *, TYVM...</title>
<updated>2022-09-01T21:34:39Z</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2022-01-31T00:57:52Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c8e477c649b40c1a073b7a843d89e51dc0037db7'/>
<id>urn:sha1:c8e477c649b40c1a073b7a843d89e51dc0037db7</id>
<content type='text'>
cast of -&gt;d_name.name to char * is completely wrong - nothing is
allowed to modify its contents.

Reviewed-by: Christian Brauner (Microsoft) &lt;brauner@kernel.org&gt;
Acked-by: Paul Moore &lt;paul@paul-moore.com&gt;
Acked-by: Casey Schaufler &lt;casey@schaufler-ca.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>lsm,io_uring: add LSM hooks for the new uring_cmd file op</title>
<updated>2022-08-26T15:19:43Z</updated>
<author>
<name>Luis Chamberlain</name>
<email>mcgrof@kernel.org</email>
</author>
<published>2022-07-15T19:16:22Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2a5840124009f133bd09fd855963551fb2cefe22'/>
<id>urn:sha1:2a5840124009f133bd09fd855963551fb2cefe22</id>
<content type='text'>
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 &lt;mcgrof@kernel.org&gt;
Acked-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>security, lsm: Introduce security_create_user_ns()</title>
<updated>2022-08-16T21:32:46Z</updated>
<author>
<name>Frederick Lawler</name>
<email>fred@cloudflare.com</email>
</author>
<published>2022-08-15T16:20:25Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7cd4c5c2101cb092db00f61f69d24380cf7a0ee8'/>
<id>urn:sha1:7cd4c5c2101cb092db00f61f69d24380cf7a0ee8</id>
<content type='text'>
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) &lt;brauner@kernel.org&gt;
Reviewed-by: KP Singh &lt;kpsingh@kernel.org&gt;
Signed-off-by: Frederick Lawler &lt;fred@cloudflare.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'safesetid-6.0' of https://github.com/micah-morton/linux</title>
<updated>2022-08-02T22:12:13Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-08-02T22:12:13Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=87fe1adb66a514fa3abbe8bdb4278a5b2f421d8b'/>
<id>urn:sha1:87fe1adb66a514fa3abbe8bdb4278a5b2f421d8b</id>
<content type='text'>
Pull SafeSetID updates from Micah Morton:
 "This contains one commit that touches common kernel code, one that
  adds functionality internal to the SafeSetID LSM code, and a few other
  commits that only modify the SafeSetID LSM selftest.

  The commit that touches common kernel code simply adds an LSM hook in
  the setgroups() syscall that mirrors what is done for the existing LSM
  hooks in the setuid() and setgid() syscalls. This commit combined with
  the SafeSetID-specific one allow the LSM to filter setgroups() calls
  according to configured rule sets in the same way that is already done
  for setuid() and setgid()"

* tag 'safesetid-6.0' of https://github.com/micah-morton/linux:
  LSM: SafeSetID: add setgroups() testing to selftest
  LSM: SafeSetID: Add setgroups() security policy handling
  security: Add LSM hook to setgroups() syscall
  LSM: SafeSetID: add GID testing to selftest
  LSM: SafeSetID: selftest cleanup and prepare for GIDs
  LSM: SafeSetID: fix userns bug in selftest
</content>
</entry>
<entry>
<title>security: Add LSM hook to setgroups() syscall</title>
<updated>2022-07-15T18:21:49Z</updated>
<author>
<name>Micah Morton</name>
<email>mortonm@chromium.org</email>
</author>
<published>2022-06-08T20:57:11Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=fcfe0ac2fcfae7d5fcad3d0375cb8ff38caf8aba'/>
<id>urn:sha1:fcfe0ac2fcfae7d5fcad3d0375cb8ff38caf8aba</id>
<content type='text'>
Give the LSM framework the ability to filter setgroups() syscalls. There
are already analagous hooks for the set*uid() and set*gid() syscalls.
The SafeSetID LSM will use this new hook to ensure setgroups() calls are
allowed by the installed security policy. Tested by putting print
statement in security_task_fix_setgroups() hook and confirming that it
gets hit when userspace does a setgroups() syscall.

Acked-by: Casey Schaufler &lt;casey@schaufler-ca.com&gt;
Reviewed-by: Serge Hallyn &lt;serge@hallyn.com&gt;
Signed-off-by: Micah Morton &lt;mortonm@chromium.org&gt;
</content>
</entry>
</feed>
