<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/ipc/mqueue.c, branch v6.1.168</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.1.168</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.1.168'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2022-12-31T12:32:01+00:00</updated>
<entry>
<title>ipc: fix memory leak in init_mqueue_fs()</title>
<updated>2022-12-31T12:32:01+00:00</updated>
<author>
<name>Zhengchao Shao</name>
<email>shaozhengchao@huawei.com</email>
</author>
<published>2022-12-09T09:29:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=28dad915abe46d38c5799a0c8130e9a2a1540385'/>
<id>urn:sha1:28dad915abe46d38c5799a0c8130e9a2a1540385</id>
<content type='text'>
[ Upstream commit 12b677f2c697d61e5ddbcb6c1650050a39392f54 ]

When setup_mq_sysctls() failed in init_mqueue_fs(), mqueue_inode_cachep is
not released.  In order to fix this issue, the release path is reordered.

Link: https://lkml.kernel.org/r/20221209092929.1978875-1-shaozhengchao@huawei.com
Fixes: dc55e35f9e81 ("ipc: Store mqueue sysctls in the ipc namespace")
Signed-off-by: Zhengchao Shao &lt;shaozhengchao@huawei.com&gt;
Cc: Alexey Gladkov &lt;legion@kernel.org&gt;
Cc: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Cc: Jingyu Wang &lt;jingyuwang_vip@163.com&gt;
Cc: Muchun Song &lt;songmuchun@bytedance.com&gt;
Cc: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Cc: Waiman Long &lt;longman@redhat.com&gt;
Cc: Wei Yongjun &lt;weiyongjun1@huawei.com&gt;
Cc: YueHaibing &lt;yuehaibing@huawei.com&gt;
Cc: Yu Zhe &lt;yuzhe@nfschina.com&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;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-10-12T18:00:22+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-12T18:00:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=676cb4957396411fdb7aba906d5f950fc3de7cc9'/>
<id>urn:sha1:676cb4957396411fdb7aba906d5f950fc3de7cc9</id>
<content type='text'>
Pull non-MM updates from Andrew Morton:

 - hfs and hfsplus kmap API modernization (Fabio Francesco)

 - make crash-kexec work properly when invoked from an NMI-time panic
   (Valentin Schneider)

 - ntfs bugfixes (Hawkins Jiawei)

 - improve IPC msg scalability by replacing atomic_t's with percpu
   counters (Jiebin Sun)

 - nilfs2 cleanups (Minghao Chi)

 - lots of other single patches all over the tree!

* tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (71 commits)
  include/linux/entry-common.h: remove has_signal comment of arch_do_signal_or_restart() prototype
  proc: test how it holds up with mapping'less process
  mailmap: update Frank Rowand email address
  ia64: mca: use strscpy() is more robust and safer
  init/Kconfig: fix unmet direct dependencies
  ia64: update config files
  nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure
  fork: remove duplicate included header files
  init/main.c: remove unnecessary (void*) conversions
  proc: mark more files as permanent
  nilfs2: remove the unneeded result variable
  nilfs2: delete unnecessary checks before brelse()
  checkpatch: warn for non-standard fixes tag style
  usr/gen_init_cpio.c: remove unnecessary -1 values from int file
  ipc/msg: mitigate the lock contention with percpu counter
  percpu: add percpu_counter_add_local and percpu_counter_sub_local
  fs/ocfs2: fix repeated words in comments
  relay: use kvcalloc to alloc page array in relay_alloc_page_array
  proc: make config PROC_CHILDREN depend on PROC_FS
  fs: uninline inode_maybe_inc_iversion()
  ...
</content>
</entry>
<entry>
<title>Merge tag 'retire_mq_sysctls-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace</title>
<updated>2022-10-09T23:10:22+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-09T23:10:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=86fb9c53d82f1dadf960553a3bd351de6173911f'/>
<id>urn:sha1:86fb9c53d82f1dadf960553a3bd351de6173911f</id>
<content type='text'>
Pull mqueue fix from Eric Biederman:
 "A fix for an unlikely but possible memory leak"

* tag 'retire_mq_sysctls-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ipc: mqueue: fix possible memory leak in init_mqueue_fs()
</content>
</entry>
<entry>
<title>ipc: mqueue: remove unnecessary conditionals</title>
<updated>2022-10-03T21:21:42+00:00</updated>
<author>
<name>Jingyu Wang</name>
<email>jingyuwang_vip@163.com</email>
</author>
<published>2022-09-08T18:54:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=5758478a3d3c42a78ee9ddc4b08db3e968a68058'/>
<id>urn:sha1:5758478a3d3c42a78ee9ddc4b08db3e968a68058</id>
<content type='text'>
iput() already handles null and non-null parameters, so there is no need
to use if().

Link: https://lkml.kernel.org/r/20220908185452.76590-1-jingyuwang_vip@163.com
Signed-off-by: Jingyu Wang &lt;jingyuwang_vip@163.com&gt;
Acked-by: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>ipc: mqueue: fix possible memory leak in init_mqueue_fs()</title>
<updated>2022-07-19T22:17:35+00:00</updated>
<author>
<name>Hangyu Hua</name>
<email>hbh25y@gmail.com</email>
</author>
<published>2022-07-15T06:23:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c579d60f0d0cd87552f64fdebe68b5d941d20309'/>
<id>urn:sha1:c579d60f0d0cd87552f64fdebe68b5d941d20309</id>
<content type='text'>
commit db7cfc380900 ("ipc: Free mq_sysctls if ipc namespace creation
failed")

Here's a similar memory leak to the one fixed by the patch above.
retire_mq_sysctls need to be called when init_mqueue_fs fails after
setup_mq_sysctls.

Fixes: dc55e35f9e81 ("ipc: Store mqueue sysctls in the ipc namespace")
Signed-off-by: Hangyu Hua &lt;hbh25y@gmail.com&gt;
Link: https://lkml.kernel.org/r/20220715062301.19311-1-hbh25y@gmail.com
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
<entry>
<title>ipc/mqueue: remove unnecessary (void*) conversion</title>
<updated>2022-07-18T00:31:40+00:00</updated>
<author>
<name>Yu Zhe</name>
<email>yuzhe@nfschina.com</email>
</author>
<published>2022-06-28T02:12:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=2c795fb03f138e9602e1f1ee31b8bfc00a96c7e5'/>
<id>urn:sha1:2c795fb03f138e9602e1f1ee31b8bfc00a96c7e5</id>
<content type='text'>
Remove unnecessary void* type casting.

Link: https://lkml.kernel.org/r/20220628021251.17197-1-yuzhe@nfschina.com
Signed-off-by: Yu Zhe &lt;yuzhe@nfschina.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'per-namespace-ipc-sysctls-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace</title>
<updated>2022-06-03T22:54:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-06-03T22:54:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=1888e9b4bb78c88514b24ecafa9e4e4faf761747'/>
<id>urn:sha1:1888e9b4bb78c88514b24ecafa9e4e4faf761747</id>
<content type='text'>
Pull ipc sysctl namespace updates from Eric Biederman:
 "This updates the ipc sysctls so that they are fundamentally per ipc
  namespace. Previously these sysctls depended upon a hack to simulate
  being per ipc namespace by looking up the ipc namespace in read or
  write. With this set of changes the ipc sysctls are registered per ipc
  namespace and open looks up the ipc namespace.

  Not only does this series of changes ensure the traditional binding at
  open time happens, but it sets a foundation for being able to relax
  the permission checks to allow a user namspace root to change the ipc
  sysctls for an ipc namespace that the user namespace root requires. To
  do this requires the ipc namespace to be known at open time"

* tag 'per-namespace-ipc-sysctls-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ipc: Remove extra braces
  ipc: Check permissions for checkpoint_restart sysctls at open time
  ipc: Remove extra1 field abuse to pass ipc namespace
  ipc: Use the same namespace to modify and validate
  ipc: Store ipc sysctls in the ipc namespace
  ipc: Store mqueue sysctls in the ipc namespace
</content>
</entry>
<entry>
<title>ipc/mqueue: use get_tree_nodev() in mqueue_get_tree()</title>
<updated>2022-05-10T01:29:21+00:00</updated>
<author>
<name>Waiman Long</name>
<email>longman@redhat.com</email>
</author>
<published>2022-05-10T01:29:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d60c4d01a98bc1942dba6e3adc02031f5519f94b'/>
<id>urn:sha1:d60c4d01a98bc1942dba6e3adc02031f5519f94b</id>
<content type='text'>
When running the stress-ng clone benchmark with multiple testing threads,
it was found that there were significant spinlock contention in sget_fc().
The contended spinlock was the sb_lock.  It is under heavy contention
because the following code in the critcal section of sget_fc():

  hlist_for_each_entry(old, &amp;fc-&gt;fs_type-&gt;fs_supers, s_instances) {
      if (test(old, fc))
          goto share_extant_sb;
  }

After testing with added instrumentation code, it was found that the
benchmark could generate thousands of ipc namespaces with the
corresponding number of entries in the mqueue's fs_supers list where the
namespaces are the key for the search.  This leads to excessive time in
scanning the list for a match.

Looking back at the mqueue calling sequence leading to sget_fc():

  mq_init_ns()
  =&gt; mq_create_mount()
  =&gt; fc_mount()
  =&gt; vfs_get_tree()
  =&gt; mqueue_get_tree()
  =&gt; get_tree_keyed()
  =&gt; vfs_get_super()
  =&gt; sget_fc()

Currently, mq_init_ns() is the only mqueue function that will indirectly
call mqueue_get_tree() with a newly allocated ipc namespace as the key for
searching.  As a result, there will never be a match with the exising ipc
namespaces stored in the mqueue's fs_supers list.

So using get_tree_keyed() to do an existing ipc namespace search is just a
waste of time.  Instead, we could use get_tree_nodev() to eliminate the
useless search.  By doing so, we can greatly reduce the sb_lock hold time
and avoid the spinlock contention problem in case a large number of ipc
namespaces are present.

Of course, if the code is modified in the future to allow
mqueue_get_tree() to be called with an existing ipc namespace instead of a
new one, we will have to use get_tree_keyed() in this case.

The following stress-ng clone benchmark command was run on a 2-socket
48-core Intel system:

./stress-ng --clone 32 --verbose --oomable --metrics-brief -t 20

The "bogo ops/s" increased from 5948.45 before patch to 9137.06 after
patch. This is an increase of 54% in performance.

Link: https://lkml.kernel.org/r/20220121172315.19652-1-longman@redhat.com
Fixes: 935c6912b198 ("ipc: Convert mqueue fs to fs_context")
Signed-off-by: Waiman Long &lt;longman@redhat.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: David Howells &lt;dhowells@redhat.com&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>fs: allocate inode by using alloc_inode_sb()</title>
<updated>2022-03-22T22:57:03+00:00</updated>
<author>
<name>Muchun Song</name>
<email>songmuchun@bytedance.com</email>
</author>
<published>2022-03-22T21:41:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=fd60b28842df833477c42da6a6d63d0d114a5fcc'/>
<id>urn:sha1:fd60b28842df833477c42da6a6d63d0d114a5fcc</id>
<content type='text'>
The inode allocation is supposed to use alloc_inode_sb(), so convert
kmem_cache_alloc() of all filesystems to alloc_inode_sb().

Link: https://lkml.kernel.org/r/20220228122126.37293-5-songmuchun@bytedance.com
Signed-off-by: Muchun Song &lt;songmuchun@bytedance.com&gt;
Acked-by: Theodore Ts'o &lt;tytso@mit.edu&gt;		[ext4]
Acked-by: Roman Gushchin &lt;roman.gushchin@linux.dev&gt;
Cc: Alex Shi &lt;alexs@kernel.org&gt;
Cc: Anna Schumaker &lt;Anna.Schumaker@Netapp.com&gt;
Cc: Chao Yu &lt;chao@kernel.org&gt;
Cc: Dave Chinner &lt;david@fromorbit.com&gt;
Cc: Fam Zheng &lt;fam.zheng@bytedance.com&gt;
Cc: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Kari Argillander &lt;kari.argillander@gmail.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michal Hocko &lt;mhocko@kernel.org&gt;
Cc: Qi Zheng &lt;zhengqi.arch@bytedance.com&gt;
Cc: Shakeel Butt &lt;shakeelb@google.com&gt;
Cc: Trond Myklebust &lt;trond.myklebust@hammerspace.com&gt;
Cc: Vladimir Davydov &lt;vdavydov.dev@gmail.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Wei Yang &lt;richard.weiyang@gmail.com&gt;
Cc: Xiongchun Duan &lt;duanxiongchun@bytedance.com&gt;
Cc: Yang Shi &lt;shy828301@gmail.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>
<entry>
<title>ipc: Store mqueue sysctls in the ipc namespace</title>
<updated>2022-03-08T19:39:40+00:00</updated>
<author>
<name>Alexey Gladkov</name>
<email>legion@kernel.org</email>
</author>
<published>2022-02-14T18:18:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=dc55e35f9e810f23dd69cfdc91a3d636023f57a2'/>
<id>urn:sha1:dc55e35f9e810f23dd69cfdc91a3d636023f57a2</id>
<content type='text'>
Right now, the mqueue sysctls take ipc namespaces into account in a
rather hacky way. This works in most cases, but does not respect the
user namespace.

Within the user namespace, the user cannot change the /proc/sys/fs/mqueue/*
parametres. This poses a problem in the rootless containers.

To solve this I changed the implementation of the mqueue sysctls just
like some other sysctls.

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

v3:
* Don't implemenet set_permissions to keep the current behavior.

v2:
* Fixed compilation problem if CONFIG_POSIX_MQUEUE_SYSCTL is not
  specified.

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Alexey Gladkov &lt;legion@kernel.org&gt;
Link: https://lkml.kernel.org/r/b0ccbb2489119f1f20c737cf1930c3a9c4e4243a.1644862280.git.legion@kernel.org
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
</entry>
</feed>
