<feed xmlns='http://www.w3.org/2005/Atom'>
<title>litmus-rt.git/ipc, branch 2012.2</title>
<subtitle>The LITMUS^RT kernel.</subtitle>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/'/>
<entry>
<title>mm: don't access vm_flags as 'int'</title>
<updated>2011-05-26T16:20:31+00:00</updated>
<author>
<name>KOSAKI Motohiro</name>
<email>kosaki.motohiro@jp.fujitsu.com</email>
</author>
<published>2011-05-26T10:16:19+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=ca16d140af91febe25daeb9e032bf8bd46b8c31f'/>
<id>ca16d140af91febe25daeb9e032bf8bd46b8c31f</id>
<content type='text'>
The type of vma-&gt;vm_flags is 'unsigned long'. Neither 'int' nor
'unsigned int'. This patch fixes such misuse.

Signed-off-by: KOSAKI Motohiro &lt;kosaki.motohiro@jp.fujitsu.com&gt;
[ Changed to use a typedef - we'll extend it to cover more cases
  later, since there has been discussion about making it a 64-bit
  type..                      - Linus ]
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The type of vma-&gt;vm_flags is 'unsigned long'. Neither 'int' nor
'unsigned int'. This patch fixes such misuse.

Signed-off-by: KOSAKI Motohiro &lt;kosaki.motohiro@jp.fujitsu.com&gt;
[ Changed to use a typedef - we'll extend it to cover more cases
  later, since there has been discussion about making it a 64-bit
  type..                      - Linus ]
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ns proc: Add support for the ipc namespace</title>
<updated>2011-05-10T21:35:47+00:00</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2010-03-08T02:48:39+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=a00eaf11a223c63fbb212369d6db69ce4c55a2d1'/>
<id>a00eaf11a223c63fbb212369d6db69ce4c55a2d1</id>
<content type='text'>
Acked-by: Daniel Lezcano &lt;daniel.lezcano@free.fr&gt;
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Acked-by: Daniel Lezcano &lt;daniel.lezcano@free.fr&gt;
Signed-off-by: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Fix common misspellings</title>
<updated>2011-03-31T14:26:23+00:00</updated>
<author>
<name>Lucas De Marchi</name>
<email>lucas.demarchi@profusion.mobi</email>
</author>
<published>2011-03-31T01:57:33+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=25985edcedea6396277003854657b5f3cb31a628'/>
<id>25985edcedea6396277003854657b5f3cb31a628</id>
<content type='text'>
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi &lt;lucas.demarchi@profusion.mobi&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi &lt;lucas.demarchi@profusion.mobi&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipc: fix util.c kernel-doc warnings</title>
<updated>2011-03-28T02:30:19+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>randy.dunlap@oracle.com</email>
</author>
<published>2011-03-26T20:27:41+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=6213cfe82461e39219a3b06ecf1d0679b4c0657f'/>
<id>6213cfe82461e39219a3b06ecf1d0679b4c0657f</id>
<content type='text'>
Fix ipc/util.c kernel-doc warnings:

  Warning(ipc/util.c:336): No description found for parameter 'ns'
  Warning(ipc/util.c:620): No description found for parameter 'ns'
  Warning(ipc/util.c:790): No description found for parameter 'ns'

Signed-off-by: Randy Dunlap &lt;randy.dunlap@oracle.com&gt;
Reviewed-by: Jesper Juhl &lt;jj@chaosbits.net&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix ipc/util.c kernel-doc warnings:

  Warning(ipc/util.c:336): No description found for parameter 'ns'
  Warning(ipc/util.c:620): No description found for parameter 'ns'
  Warning(ipc/util.c:790): No description found for parameter 'ns'

Signed-off-by: Randy Dunlap &lt;randy.dunlap@oracle.com&gt;
Reviewed-by: Jesper Juhl &lt;jj@chaosbits.net&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipcns: fix use after free in free_ipc_ns()</title>
<updated>2011-03-26T00:45:16+00:00</updated>
<author>
<name>Xiaotian Feng</name>
<email>dfeng@redhat.com</email>
</author>
<published>2011-03-25T08:57:01+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=be4d250ab41e13f8f945be6896695e870b38ba31'/>
<id>be4d250ab41e13f8f945be6896695e870b38ba31</id>
<content type='text'>
commit b515498 ("userns: add a user namespace owner of ipc ns") added a
user namespace owner of ipc ns, but it also introduced a use after free in
free_ipc_ns().

Signed-off-by: Xiaotian Feng &lt;dfeng@redhat.com&gt;
Acked-by: "Serge E. Hallyn" &lt;serge.hallyn@canonical.com&gt;
Acked-by: David Howells &lt;dhowells@redhat.com&gt;
Cc: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Cc: Daniel Lezcano &lt;daniel.lezcano@free.fr&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b515498 ("userns: add a user namespace owner of ipc ns") added a
user namespace owner of ipc ns, but it also introduced a use after free in
free_ipc_ns().

Signed-off-by: Xiaotian Feng &lt;dfeng@redhat.com&gt;
Acked-by: "Serge E. Hallyn" &lt;serge.hallyn@canonical.com&gt;
Acked-by: David Howells &lt;dhowells@redhat.com&gt;
Cc: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Cc: Daniel Lezcano &lt;daniel.lezcano@free.fr&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>userns: user namespaces: convert several capable() calls</title>
<updated>2011-03-24T02:47:08+00:00</updated>
<author>
<name>Serge E. Hallyn</name>
<email>serge@hallyn.com</email>
</author>
<published>2011-03-23T23:43:24+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=b0e77598f87107001a00b8a4ece9c95e4254ccc4'/>
<id>b0e77598f87107001a00b8a4ece9c95e4254ccc4</id>
<content type='text'>
CAP_IPC_OWNER and CAP_IPC_LOCK can be checked against current_user_ns(),
because the resource comes from current's own ipc namespace.

setuid/setgid are to uids in own namespace, so again checks can be against
current_user_ns().

Changelog:
	Jan 11: Use task_ns_capable() in place of sched_capable().
	Jan 11: Use nsown_capable() as suggested by Bastian Blank.
	Jan 11: Clarify (hopefully) some logic in futex and sched.c
	Feb 15: use ns_capable for ipc, not nsown_capable
	Feb 23: let copy_ipcs handle setting ipc_ns-&gt;user_ns
	Feb 23: pass ns down rather than taking it from current

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Serge E. Hallyn &lt;serge.hallyn@canonical.com&gt;
Acked-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Acked-by: Daniel Lezcano &lt;daniel.lezcano@free.fr&gt;
Acked-by: David Howells &lt;dhowells@redhat.com&gt;
Cc: James Morris &lt;jmorris@namei.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
CAP_IPC_OWNER and CAP_IPC_LOCK can be checked against current_user_ns(),
because the resource comes from current's own ipc namespace.

setuid/setgid are to uids in own namespace, so again checks can be against
current_user_ns().

Changelog:
	Jan 11: Use task_ns_capable() in place of sched_capable().
	Jan 11: Use nsown_capable() as suggested by Bastian Blank.
	Jan 11: Clarify (hopefully) some logic in futex and sched.c
	Feb 15: use ns_capable for ipc, not nsown_capable
	Feb 23: let copy_ipcs handle setting ipc_ns-&gt;user_ns
	Feb 23: pass ns down rather than taking it from current

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Serge E. Hallyn &lt;serge.hallyn@canonical.com&gt;
Acked-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Acked-by: Daniel Lezcano &lt;daniel.lezcano@free.fr&gt;
Acked-by: David Howells &lt;dhowells@redhat.com&gt;
Cc: James Morris &lt;jmorris@namei.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>userns: add a user namespace owner of ipc ns</title>
<updated>2011-03-24T02:47:07+00:00</updated>
<author>
<name>Serge E. Hallyn</name>
<email>serge@hallyn.com</email>
</author>
<published>2011-03-23T23:43:23+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=b515498f5bb5f38fc0e390b4ff7d00b6077de127'/>
<id>b515498f5bb5f38fc0e390b4ff7d00b6077de127</id>
<content type='text'>
Changelog:
	Feb 15: Don't set new ipc-&gt;user_ns if we didn't create a new
		ipc_ns.
	Feb 23: Move extern declaration to ipc_namespace.h, and group
		fwd declarations at top.

Signed-off-by: Serge E. Hallyn &lt;serge.hallyn@canonical.com&gt;
Acked-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Acked-by: Daniel Lezcano &lt;daniel.lezcano@free.fr&gt;
Acked-by: David Howells &lt;dhowells@redhat.com&gt;
Cc: James Morris &lt;jmorris@namei.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Changelog:
	Feb 15: Don't set new ipc-&gt;user_ns if we didn't create a new
		ipc_ns.
	Feb 23: Move extern declaration to ipc_namespace.h, and group
		fwd declarations at top.

Signed-off-by: Serge E. Hallyn &lt;serge.hallyn@canonical.com&gt;
Acked-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Acked-by: Daniel Lezcano &lt;daniel.lezcano@free.fr&gt;
Acked-by: David Howells &lt;dhowells@redhat.com&gt;
Cc: James Morris &lt;jmorris@namei.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fs: icache RCU free inodes</title>
<updated>2011-01-07T06:50:26+00:00</updated>
<author>
<name>Nick Piggin</name>
<email>npiggin@kernel.dk</email>
</author>
<published>2011-01-07T06:49:49+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=fa0d7e3de6d6fc5004ad9dea0dd6b286af8f03e9'/>
<id>fa0d7e3de6d6fc5004ad9dea0dd6b286af8f03e9</id>
<content type='text'>
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page-&gt;mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin &lt;npiggin@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page-&gt;mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin &lt;npiggin@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipc: shm: fix information leak to userland</title>
<updated>2010-10-30T15:25:51+00:00</updated>
<author>
<name>Vasiliy Kulikov</name>
<email>segooon@gmail.com</email>
</author>
<published>2010-10-30T14:22:49+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=3af54c9bd9e6f14f896aac1bb0e8405ae0bc7a44'/>
<id>3af54c9bd9e6f14f896aac1bb0e8405ae0bc7a44</id>
<content type='text'>
The shmid_ds structure is copied to userland with shm_unused{,2,3}
fields unitialized.  It leads to leaking of contents of kernel stack
memory.

Signed-off-by: Vasiliy Kulikov &lt;segooon@gmail.com&gt;
Acked-by: Al Viro &lt;viro@ZenIV.linux.org.uk&gt;
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The shmid_ds structure is copied to userland with shm_unused{,2,3}
fields unitialized.  It leads to leaking of contents of kernel stack
memory.

Signed-off-by: Vasiliy Kulikov &lt;segooon@gmail.com&gt;
Acked-by: Al Viro &lt;viro@ZenIV.linux.org.uk&gt;
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>switch get_sb_ns() users</title>
<updated>2010-10-29T08:17:03+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2010-07-26T09:16:50+00:00</published>
<link rel='alternate' type='text/html' href='http://rtsrv.cs.unc.edu/cgit/cgit.cgi/litmus-rt.git/commit/?id=ceefda6931806972ecf550bd8231dce4a4178953'/>
<id>ceefda6931806972ecf550bd8231dce4a4178953</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
</feed>
