<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/kernel/audit.c, branch v6.4.15</title>
<subtitle>Linux Kernel
</subtitle>
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<updated>2022-08-29T23:47:03Z</updated>
<entry>
<title>audit: use time_after to compare time</title>
<updated>2022-08-29T23:47:03Z</updated>
<author>
<name>wuchi</name>
<email>wuchi.zero@gmail.com</email>
</author>
<published>2022-08-29T16:26:09Z</published>
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<id>urn:sha1:501e4bb102ee2f380ab94abbf3d35dff9d4719a2</id>
<content type='text'>
Using time_{*} macro to compare time is better

Signed-off-by: wuchi &lt;wuchi.zero@gmail.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>audit: make is_audit_feature_set() static</title>
<updated>2022-06-13T18:08:57Z</updated>
<author>
<name>Xiu Jianfeng</name>
<email>xiujianfeng@huawei.com</email>
</author>
<published>2022-06-11T09:23:04Z</published>
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<id>urn:sha1:546093206ba16623c18e344630dbfdd71a4327e0</id>
<content type='text'>
Currently nobody use is_audit_feature_set() outside this file, so make
it static.

Signed-off-by: Xiu Jianfeng &lt;xiujianfeng@huawei.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>audit: remove redundant data_len check</title>
<updated>2022-06-07T19:41:34Z</updated>
<author>
<name>Shreenidhi Shedi</name>
<email>yesshedi@gmail.com</email>
</author>
<published>2022-05-15T07:31:09Z</published>
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<id>urn:sha1:5ee6cfdd11aaf5aee5cd48baf35b1710caa68a5c</id>
<content type='text'>
data_len is already getting checked if it's less than 2 earlier in this
function.

Signed-off-by: Shreenidhi Shedi &lt;sshedi@vmware.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>audit: improve audit queue handling when "audit=1" on cmdline</title>
<updated>2022-01-25T18:22:51Z</updated>
<author>
<name>Paul Moore</name>
<email>paul@paul-moore.com</email>
</author>
<published>2022-01-13T23:54:38Z</published>
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<id>urn:sha1:f26d04331360d42dbd6b58448bd98e4edbfbe1c5</id>
<content type='text'>
When an admin enables audit at early boot via the "audit=1" kernel
command line the audit queue behavior is slightly different; the
audit subsystem goes to greater lengths to avoid dropping records,
which unfortunately can result in problems when the audit daemon is
forcibly stopped for an extended period of time.

This patch makes a number of changes designed to improve the audit
queuing behavior so that leaving the audit daemon in a stopped state
for an extended period does not cause a significant impact to the
system.

- kauditd_send_queue() is now limited to looping through the
  passed queue only once per call.  This not only prevents the
  function from looping indefinitely when records are returned
  to the current queue, it also allows any recovery handling in
  kauditd_thread() to take place when kauditd_send_queue()
  returns.

- Transient netlink send errors seen as -EAGAIN now cause the
  record to be returned to the retry queue instead of going to
  the hold queue.  The intention of the hold queue is to store,
  perhaps for an extended period of time, the events which led
  up to the audit daemon going offline.  The retry queue remains
  a temporary queue intended to protect against transient issues
  between the kernel and the audit daemon.

- The retry queue is now limited by the audit_backlog_limit
  setting, the same as the other queues.  This allows admins
  to bound the size of all of the audit queues on the system.

- kauditd_rehold_skb() now returns records to the end of the
  hold queue to ensure ordering is preserved in the face of
  recent changes to kauditd_send_queue().

Cc: stable@vger.kernel.org
Fixes: 5b52330bbfe63 ("audit: fix auditd/kernel connection state tracking")
Fixes: f4b3ee3c85551 ("audit: improve robustness of the audit queue handling")
Reported-by: Gaosheng Cui &lt;cuigaosheng1@huawei.com&gt;
Tested-by: Gaosheng Cui &lt;cuigaosheng1@huawei.com&gt;
Reviewed-by: Richard Guy Briggs &lt;rgb@redhat.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'audit-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit</title>
<updated>2022-01-11T21:08:21Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-01-11T21:08:21Z</published>
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<id>urn:sha1:5d7e52237c59e37a25da854196fc70e9b09704d9</id>
<content type='text'>
Pull audit updates from Paul Moore:
 "Four audit patches for v5.17:

   - Harden the code through additional use of the struct_size() macro
     and zero-length arrays to flexible-array conversions.

   - Ensure that processes which generate userspace audit records are
     not exempt from the kernel's audit throttling when the audit queues
     are being overrun"

* tag 'audit-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: replace zero-length array with flexible-array member
  audit: use struct_size() helper in audit_[send|make]_reply()
  audit: ensure userspace is penalized the same as the kernel when under pressure
  audit: use struct_size() helper in kmalloc()
</content>
</entry>
<entry>
<title>Merge tag 'selinux-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux</title>
<updated>2022-01-11T21:03:06Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-01-11T21:03:06Z</published>
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<id>urn:sha1:a135ce4400bb87f229ab33a663987327d9e0b2a0</id>
<content type='text'>
Pull selinux updates from Paul Moore:
 "Nothing too significant, but five SELinux patches for v5.17 that do
  the following:

   - Harden the code through additional use of the struct_size() macro

   - Plug some memory leaks

   - Clean up the code via removal of the security_add_mnt_opt() LSM
     hook and minor tweaks to selinux_add_opt()

   - Rename security_task_getsecid_subj() to better reflect its actual
     behavior/use - now called security_current_getsecid_subj()"

* tag 'selinux-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: minor tweaks to selinux_add_opt()
  selinux: fix potential memleak in selinux_add_opt()
  security,selinux: remove security_add_mnt_opt()
  selinux: Use struct_size() helper in kmalloc()
  lsm: security_task_getsecid_subj() -&gt; security_current_getsecid_subj()
</content>
</entry>
<entry>
<title>audit: use struct_size() helper in audit_[send|make]_reply()</title>
<updated>2021-12-20T19:42:11Z</updated>
<author>
<name>Xiu Jianfeng</name>
<email>xiujianfeng@huawei.com</email>
</author>
<published>2021-12-17T01:01:51Z</published>
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<id>urn:sha1:30561b51cc8d1daa27a48eb29dd9424858576b19</id>
<content type='text'>
Make use of struct_size() helper instead of an open-coded calculation.

Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Xiu Jianfeng &lt;xiujianfeng@huawei.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>audit: improve robustness of the audit queue handling</title>
<updated>2021-12-15T18:16:39Z</updated>
<author>
<name>Paul Moore</name>
<email>paul@paul-moore.com</email>
</author>
<published>2021-12-09T16:46:07Z</published>
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<id>urn:sha1:f4b3ee3c85551d2d343a3ba159304066523f730f</id>
<content type='text'>
If the audit daemon were ever to get stuck in a stopped state the
kernel's kauditd_thread() could get blocked attempting to send audit
records to the userspace audit daemon.  With the kernel thread
blocked it is possible that the audit queue could grow unbounded as
certain audit record generating events must be exempt from the queue
limits else the system enter a deadlock state.

This patch resolves this problem by lowering the kernel thread's
socket sending timeout from MAX_SCHEDULE_TIMEOUT to HZ/10 and tweaks
the kauditd_send_queue() function to better manage the various audit
queues when connection problems occur between the kernel and the
audit daemon.  With this patch, the backlog may temporarily grow
beyond the defined limits when the audit daemon is stopped and the
system is under heavy audit pressure, but kauditd_thread() will
continue to make progress and drain the queues as it would for other
connection problems.  For example, with the audit daemon put into a
stopped state and the system configured to audit every syscall it
was still possible to shutdown the system without a kernel panic,
deadlock, etc.; granted, the system was slow to shutdown but that is
to be expected given the extreme pressure of recording every syscall.

The timeout value of HZ/10 was chosen primarily through
experimentation and this developer's "gut feeling".  There is likely
no one perfect value, but as this scenario is limited in scope (root
privileges would be needed to send SIGSTOP to the audit daemon), it
is likely not worth exposing this as a tunable at present.  This can
always be done at a later date if it proves necessary.

Cc: stable@vger.kernel.org
Fixes: 5b52330bbfe63 ("audit: fix auditd/kernel connection state tracking")
Reported-by: Gaosheng Cui &lt;cuigaosheng1@huawei.com&gt;
Tested-by: Gaosheng Cui &lt;cuigaosheng1@huawei.com&gt;
Reviewed-by: Richard Guy Briggs &lt;rgb@redhat.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>audit: ensure userspace is penalized the same as the kernel when under pressure</title>
<updated>2021-12-15T18:10:32Z</updated>
<author>
<name>Paul Moore</name>
<email>paul@paul-moore.com</email>
</author>
<published>2021-12-13T20:45:20Z</published>
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<id>urn:sha1:8f110f530635af44fff1f4ee100ecef0bac62510</id>
<content type='text'>
Due to the audit control mutex necessary for serializing audit
userspace messages we haven't been able to block/penalize userspace
processes that attempt to send audit records while the system is
under audit pressure.  The result is that privileged userspace
applications have a priority boost with respect to audit as they are
not bound by the same audit queue throttling as the other tasks on
the system.

This patch attempts to restore some balance to the system when under
audit pressure by blocking these privileged userspace tasks after
they have finished their audit processing, and dropped the audit
control mutex, but before they return to userspace.

Reported-by: Gaosheng Cui &lt;cuigaosheng1@huawei.com&gt;
Tested-by: Gaosheng Cui &lt;cuigaosheng1@huawei.com&gt;
Reviewed-by: Richard Guy Briggs &lt;rgb@redhat.com&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>audit: use struct_size() helper in kmalloc()</title>
<updated>2021-12-14T22:39:42Z</updated>
<author>
<name>Xiu Jianfeng</name>
<email>xiujianfeng@huawei.com</email>
</author>
<published>2021-12-14T11:48:54Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=bc6e60a4fc1daef2d95367fea8ee74fc5b62b7d6'/>
<id>urn:sha1:bc6e60a4fc1daef2d95367fea8ee74fc5b62b7d6</id>
<content type='text'>
Make use of struct_size() helper instead of an open-coded calucation.

Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Xiu Jianfeng &lt;xiujianfeng@huawei.com&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
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