<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/ipc/ipc_sysctl.c, branch v6.9.3</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.9.3</id>
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<updated>2024-03-18T21:59:13Z</updated>
<entry>
<title>Merge tag 'sysctl-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl</title>
<updated>2024-03-18T21:59:13Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-03-18T21:59:13Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2cb5c8683981ebd5033e3cc91f7dd75794f16e61'/>
<id>urn:sha1:2cb5c8683981ebd5033e3cc91f7dd75794f16e61</id>
<content type='text'>
Pull sysctl updates from Joel Granados:
 "No functional changes - additional testing is required for the rest of
  the pending changes.

   - New shared repo for sysctl maintenance

   - check-sysctl-docs adjustment for API changes by Thomas Weißschuh"

* tag 'sysctl-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl:
  scripts: check-sysctl-docs: handle per-namespace sysctls
  ipc: remove linebreaks from arguments of __register_sysctl_table
  scripts: check-sysctl-docs: adapt to new API
  MAINTAINERS: Update sysctl tree location
</content>
</entry>
<entry>
<title>ipc: remove linebreaks from arguments of __register_sysctl_table</title>
<updated>2024-02-23T11:13:09Z</updated>
<author>
<name>Thomas Weißschuh</name>
<email>linux@weissschuh.net</email>
</author>
<published>2024-02-19T20:19:23Z</published>
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<id>urn:sha1:8e88291043155956c2851c44e8fd0a562ea2ee49</id>
<content type='text'>
Calls to __register_sysctl_table will be validated by
scripts/check-sysctl-docs. As this script is line-based remove the
linebreak which would confuse the script.

Signed-off-by: Thomas Weißschuh &lt;linux@weissschuh.net&gt;
Reviewed-by: Joel Granados &lt;j.granados@samsung.com&gt;
Signed-off-by: Joel Granados &lt;j.granados@samsung.com&gt;
</content>
</entry>
<entry>
<title>sysctl: allow change system v ipc sysctls inside ipc namespace</title>
<updated>2024-02-22T23:38:52Z</updated>
<author>
<name>Alexey Gladkov</name>
<email>legion@kernel.org</email>
</author>
<published>2024-01-15T15:46:41Z</published>
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<id>urn:sha1:50ec499b9a43e46200c9f7b7d723ab2e4af540b3</id>
<content type='text'>
Patch series "Allow to change ipc/mq sysctls inside ipc namespace", v3.

Right now ipc and mq limits count as per ipc namespace, but only real root
can change them.  By default, the current values of these limits are such
that it can only be reduced.  Since only root can change the values, it is
impossible to reduce these limits in the rootless container.

We can allow limit changes within ipc namespace because mq parameters are
limited by RLIMIT_MSGQUEUE and ipc parameters are not limited to anything
other than cgroups.


This patch (of 3):

Rootless containers are not allowed to modify kernel IPC parameters.

All default limits are set to such high values that in fact there are no
limits at all.  All limits are not inherited and are initialized to
default values when a new ipc_namespace is created.

For new ipc_namespace:

size_t       ipc_ns.shm_ctlmax = SHMMAX; // (ULONG_MAX - (1UL &lt;&lt; 24))
size_t       ipc_ns.shm_ctlall = SHMALL; // (ULONG_MAX - (1UL &lt;&lt; 24))
int          ipc_ns.shm_ctlmni = IPCMNI; // (1 &lt;&lt; 15)
int          ipc_ns.shm_rmid_forced = 0;
unsigned int ipc_ns.msg_ctlmax = MSGMAX; // 8192
unsigned int ipc_ns.msg_ctlmni = MSGMNI; // 32000
unsigned int ipc_ns.msg_ctlmnb = MSGMNB; // 16384

The shm_tot (total amount of shared pages) has also ceased to be global,
it is located in ipc_namespace and is not inherited from anywhere.

In such conditions, it cannot be said that these limits limit anything. 
The real limiter for them is cgroups.

If we allow rootless containers to change these parameters, then it can
only be reduced.

Link: https://lkml.kernel.org/r/cover.1705333426.git.legion@kernel.org
Link: https://lkml.kernel.org/r/d2f4603305cbfed58a24755aa61d027314b73a45.1705333426.git.legion@kernel.org
Signed-off-by: Alexey Gladkov &lt;legion@kernel.org&gt;
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Link: https://lkml.kernel.org/r/e2d84d3ec0172cfff759e6065da84ce0cc2736f8.1663756794.git.legion@kernel.org
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Joel Granados &lt;joel.granados@gmail.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>sysctl: Add a size arg to __register_sysctl_table</title>
<updated>2023-08-15T22:26:17Z</updated>
<author>
<name>Joel Granados</name>
<email>joel.granados@gmail.com</email>
</author>
<published>2023-08-09T10:49:57Z</published>
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<id>urn:sha1:bff97cf11b261972cae90299432238cc9a9a6a51</id>
<content type='text'>
We make these changes in order to prepare __register_sysctl_table and
its callers for when we remove the sentinel element (empty element at
the end of ctl_table arrays). We don't actually remove any sentinels in
this commit, but we *do* make sure to use ARRAY_SIZE so the table_size
is available when the removal occurs.

We add a table_size argument to __register_sysctl_table and adjust
callers, all of which pass ctl_table pointers and need an explicit call
to ARRAY_SIZE. We implement a size calculation in register_net_sysctl in
order to forward the size of the array pointer received from the network
register calls.

The new table_size argument does not yet have any effect in the
init_header call which is still dependent on the sentinel's presence.
table_size *does* however drive the `kzalloc` allocation in
__register_sysctl_table with no adverse effects as the allocated memory
is either one element greater than the calculated ctl_table array (for
the calls in ipc_sysctl.c, mq_sysctl.c and ucount.c) or the exact size
of the calculated ctl_table array (for the call from sysctl_net.c and
register_sysctl). This approach will allows us to "just" remove the
sentinel without further changes to __register_sysctl_table as
table_size will represent the exact size for all the callers at that
point.

Signed-off-by: Joel Granados &lt;j.granados@samsung.com&gt;
Signed-off-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
</content>
</entry>
<entry>
<title>ipc: Remove extra braces</title>
<updated>2022-05-03T22:25:58Z</updated>
<author>
<name>Alexey Gladkov</name>
<email>legion@kernel.org</email>
</author>
<published>2022-05-03T13:39:57Z</published>
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<id>urn:sha1:38cd5b12b7854941ede1954cf5a2393eb94b5d37</id>
<content type='text'>
Fix coding style. In the previous commit, I added braces because,
in addition to changing .data, .extra1 also changed. Now this is not
needed.

Fixes: 1f5c135ee509 ("ipc: Store ipc sysctls in the ipc namespace")
Signed-off-by: Alexey Gladkov &lt;legion@kernel.org&gt;
Link: https://lkml.kernel.org/r/37687827f630bc150210f5b8abeeb00f1336814e.1651584847.git.legion@kernel.org
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
<entry>
<title>ipc: Check permissions for checkpoint_restart sysctls at open time</title>
<updated>2022-05-03T22:25:58Z</updated>
<author>
<name>Alexey Gladkov</name>
<email>legion@kernel.org</email>
</author>
<published>2022-05-03T13:39:56Z</published>
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<id>urn:sha1:0889f44e281034e180daa6daf3e2d57c012452d4</id>
<content type='text'>
As Eric Biederman pointed out, it is possible not to use a custom
proc_handler and check permissions for every write, but to use a
.permission handler. That will allow the checkpoint_restart sysctls to
perform all of their permission checks at open time, and not need any
other special code.

Link: https://lore.kernel.org/lkml/87czib9g38.fsf@email.froward.int.ebiederm.org/
Fixes: 1f5c135ee509 ("ipc: Store ipc sysctls in the ipc namespace")
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Signed-off-by: Alexey Gladkov &lt;legion@kernel.org&gt;
Link: https://lkml.kernel.org/r/65fa8459803830608da4610a39f33c76aa933eb9.1651584847.git.legion@kernel.org
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
<entry>
<title>ipc: Remove extra1 field abuse to pass ipc namespace</title>
<updated>2022-05-03T22:25:58Z</updated>
<author>
<name>Alexey Gladkov</name>
<email>legion@kernel.org</email>
</author>
<published>2022-05-03T13:39:55Z</published>
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<id>urn:sha1:dd141a4955d5ebbb3f4c7996796e86a3ac9ed57f</id>
<content type='text'>
Eric Biederman pointed out that using .extra1 to pass ipc namespace
looks like an ugly hack and there is a better solution. We can get the
ipc_namespace using the .data field.

Link: https://lore.kernel.org/lkml/87czib9g38.fsf@email.froward.int.ebiederm.org/
Fixes: 1f5c135ee509 ("ipc: Store ipc sysctls in the ipc namespace")
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Signed-off-by: Alexey Gladkov &lt;legion@kernel.org&gt;
Link: https://lkml.kernel.org/r/93df64a8fe93ba20ebbe1d9f8eda484b2f325426.1651584847.git.legion@kernel.org
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
<entry>
<title>ipc: Use the same namespace to modify and validate</title>
<updated>2022-05-03T22:25:58Z</updated>
<author>
<name>Alexey Gladkov</name>
<email>legion@kernel.org</email>
</author>
<published>2022-05-03T13:39:54Z</published>
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<id>urn:sha1:def7343ff03bbb36ce7a34dcb19cab599f0da446</id>
<content type='text'>
In the 1f5c135ee509 ("ipc: Store ipc sysctls in the ipc namespace") I
missed that in addition to the modification of sem_ctls[3], the change
is validated. This validation must occur in the same namespace.

Link: https://lore.kernel.org/lkml/875ymnvryb.fsf@email.froward.int.ebiederm.org/
Fixes: 1f5c135ee509 ("ipc: Store ipc sysctls in the ipc namespace")
Signed-off-by: Alexey Gladkov &lt;legion@kernel.org&gt;
Link: https://lkml.kernel.org/r/b3cb9a25cce6becbef77186bc1216071a08a969b.1651584847.git.legion@kernel.org
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
<entry>
<title>ipc: Store ipc sysctls in the ipc namespace</title>
<updated>2022-03-08T19:39:40Z</updated>
<author>
<name>Alexey Gladkov</name>
<email>legion@kernel.org</email>
</author>
<published>2022-02-14T18:18:15Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=1f5c135ee509e89e0cc274333a65f73c62cb16e5'/>
<id>urn:sha1:1f5c135ee509e89e0cc274333a65f73c62cb16e5</id>
<content type='text'>
The ipc sysctls are not available for modification inside the user
namespace. Following the mqueue sysctls, we changed the implementation
to be more userns friendly.

So far, the changes do not provide additional access to files. This
will be done in a future patch.

Signed-off-by: Alexey Gladkov &lt;legion@kernel.org&gt;
Link: https://lkml.kernel.org/r/be6f9d014276f4dddd0c3aa05a86052856c1c555.1644862280.git.legion@kernel.org
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
<entry>
<title>ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL</title>
<updated>2021-11-09T18:02:53Z</updated>
<author>
<name>Manfred Spraul</name>
<email>manfred@colorfullife.com</email>
</author>
<published>2021-11-09T02:36:02Z</published>
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<id>urn:sha1:0e9beb8a96f21a6df1579cb3a679e150e3269d80</id>
<content type='text'>
Compilation of ipc/ipc_sysctl.c is controlled by
obj-$(CONFIG_SYSVIPC_SYSCTL)
[see ipc/Makefile]

And CONFIG_SYSVIPC_SYSCTL depends on SYSCTL
[see init/Kconfig]

An SYSCTL is selected by PROC_SYSCTL.
[see fs/proc/Kconfig]

Thus: #ifndef CONFIG_PROC_SYSCTL in ipc/ipc_sysctl.c is impossible, the
fallback can be removed.

Link: https://lkml.kernel.org/r/20210918145337.3369-1-manfred@colorfullife.com
Signed-off-by: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Reviewed-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Acked-by: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Cc: Manfred Spraul &lt;manfred@colorfullife.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
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