<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/fs/binfmt_misc.c, branch v2.6.31.2</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>fs/binfmt_misc.c: add terminating newline to /proc/sys/fs/binfmt_misc/status</title>
<updated>2009-01-06T23:59:19+00:00</updated>
<author>
<name>Qinghuang Feng</name>
<email>qhfeng.kernel@gmail.com</email>
</author>
<published>2009-01-06T22:41:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=87113e806a9ee48c6c989513ef3e9c1d31e06ac4'/>
<id>87113e806a9ee48c6c989513ef3e9c1d31e06ac4</id>
<content type='text'>
The following is what it looks like before patching.
It is not much readable.

user@ubuntu:/proc/sys/fs/binfmt_misc$ cat status
enableduser@ubuntu:/proc/sys/fs/binfmt_misc$

Signed-off-by: Qinghuang Feng &lt;qhfeng.kernel@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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The following is what it looks like before patching.
It is not much readable.

user@ubuntu:/proc/sys/fs/binfmt_misc$ cat status
enableduser@ubuntu:/proc/sys/fs/binfmt_misc$

Signed-off-by: Qinghuang Feng &lt;qhfeng.kernel@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;
</pre>
</div>
</content>
</entry>
<entry>
<title>zero i_uid/i_gid on inode allocation</title>
<updated>2009-01-05T16:54:28+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2008-12-09T14:34:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=56ff5efad96182f4d3cb3dc6b07396762c658f16'/>
<id>56ff5efad96182f4d3cb3dc6b07396762c658f16</id>
<content type='text'>
... and don't bother in callers.  Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.

i_mode is not worth the effort; it has no common default value.

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>
... and don't bother in callers.  Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.

i_mode is not worth the effort; it has no common default value.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Allow recursion in binfmt_script and binfmt_misc</title>
<updated>2008-10-16T18:21:38+00:00</updated>
<author>
<name>Kirill A. Shutemov</name>
<email>kirill@shutemov.name</email>
</author>
<published>2008-10-16T05:02:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bf2a9a39639b8b51377905397a5005f444e9a892'/>
<id>bf2a9a39639b8b51377905397a5005f444e9a892</id>
<content type='text'>
binfmt_script and binfmt_misc disallow recursion to avoid stack overflow
using sh_bang and misc_bang.  It causes problem in some cases:

$ echo '#!/bin/ls' &gt; /tmp/t0
$ echo '#!/tmp/t0' &gt; /tmp/t1
$ echo '#!/tmp/t1' &gt; /tmp/t2
$ chmod +x /tmp/t*
$ /tmp/t2
zsh: exec format error: /tmp/t2

Similar problem with binfmt_misc.

This patch introduces field 'recursion_depth' into struct linux_binprm to
track recursion level in binfmt_misc and binfmt_script.  If recursion
level more then BINPRM_MAX_RECURSION it generates -ENOEXEC.

[akpm@linux-foundation.org: make linux_binprm.recursion_depth a uint]
Signed-off-by: Kirill A. Shutemov &lt;kirill@shutemov.name&gt;
Cc: Pavel Emelyanov &lt;xemul@openvz.org&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&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>
binfmt_script and binfmt_misc disallow recursion to avoid stack overflow
using sh_bang and misc_bang.  It causes problem in some cases:

$ echo '#!/bin/ls' &gt; /tmp/t0
$ echo '#!/tmp/t0' &gt; /tmp/t1
$ echo '#!/tmp/t1' &gt; /tmp/t2
$ chmod +x /tmp/t*
$ /tmp/t2
zsh: exec format error: /tmp/t2

Similar problem with binfmt_misc.

This patch introduces field 'recursion_depth' into struct linux_binprm to
track recursion level in binfmt_misc and binfmt_script.  If recursion
level more then BINPRM_MAX_RECURSION it generates -ENOEXEC.

[akpm@linux-foundation.org: make linux_binprm.recursion_depth a uint]
Signed-off-by: Kirill A. Shutemov &lt;kirill@shutemov.name&gt;
Cc: Pavel Emelyanov &lt;xemul@openvz.org&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&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>binfmt_misc: fix false -ENOEXEC when coupled with other binary handlers</title>
<updated>2008-08-20T22:40:31+00:00</updated>
<author>
<name>Pavel Emelyanov</name>
<email>xemul@openvz.org</email>
</author>
<published>2008-08-20T21:09:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ff9bc512f198eb47204f55b24c6fe3d36ed89592'/>
<id>ff9bc512f198eb47204f55b24c6fe3d36ed89592</id>
<content type='text'>
In case the binfmt_misc binary handler is registered *before* the e.g.
script one (when for example being compiled as a module) the following
situation may occur:

1. user launches a script, whose interpreter is a misc binary;
2. the load_misc_binary sets the misc_bang and returns -ENOEVEC,
   since the binary is a script;
3. the load_script_binary loads one and calls for search_binary_hander
   to run the interpreter;
4. the load_misc_binary is called again, but refuses to load the
   binary due to misc_bang bit set.

The fix is to move the misc_bang setting lower - prior to the actual
call to the search_binary_handler.

Caused by the commit 3a2e7f47 (binfmt_misc.c: avoid potential kernel
stack overflow)

Signed-off-by: Pavel Emelyanov &lt;xemul@openvz.org&gt;
Reported-by: Kirill A. Shutemov &lt;kirill@shutemov.name&gt;
Tested-by: Kirill A. Shutemov &lt;kirill@shutemov.name&gt;
Cc: &lt;stable@kernel.org&gt;		[2.6.26.x]
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>
In case the binfmt_misc binary handler is registered *before* the e.g.
script one (when for example being compiled as a module) the following
situation may occur:

1. user launches a script, whose interpreter is a misc binary;
2. the load_misc_binary sets the misc_bang and returns -ENOEVEC,
   since the binary is a script;
3. the load_script_binary loads one and calls for search_binary_hander
   to run the interpreter;
4. the load_misc_binary is called again, but refuses to load the
   binary due to misc_bang bit set.

The fix is to move the misc_bang setting lower - prior to the actual
call to the search_binary_handler.

Caused by the commit 3a2e7f47 (binfmt_misc.c: avoid potential kernel
stack overflow)

Signed-off-by: Pavel Emelyanov &lt;xemul@openvz.org&gt;
Reported-by: Kirill A. Shutemov &lt;kirill@shutemov.name&gt;
Tested-by: Kirill A. Shutemov &lt;kirill@shutemov.name&gt;
Cc: &lt;stable@kernel.org&gt;		[2.6.26.x]
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>binfmt_misc: use simple_read_from_buffer()</title>
<updated>2008-07-24T17:47:27+00:00</updated>
<author>
<name>Akinobu Mita</name>
<email>akinobu.mita@gmail.com</email>
</author>
<published>2008-07-24T04:29:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6e2c10a12a2170856f5582d62d583cbcd1cb5eaf'/>
<id>6e2c10a12a2170856f5582d62d583cbcd1cb5eaf</id>
<content type='text'>
Signed-off-by: Akinobu Mita &lt;akinobu.mita@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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Akinobu Mita &lt;akinobu.mita@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;
</pre>
</div>
</content>
</entry>
<entry>
<title>binfmt_misc.c: avoid potential kernel stack overflow</title>
<updated>2008-04-29T15:06:04+00:00</updated>
<author>
<name>Pavel Emelyanov</name>
<email>xemul@openvz.org</email>
</author>
<published>2008-04-29T07:59:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3a2e7f47d71e1df86acc1dda6826890b6546a4e1'/>
<id>3a2e7f47d71e1df86acc1dda6826890b6546a4e1</id>
<content type='text'>
This can be triggered with root help only, but...

Register the ":text:E::txt::/root/cat.txt:' rule in binfmt_misc (by root) and
try launching the cat.txt file (by anyone) :) The result is - the endless
recursion in the load_misc_binary -&gt; open_exec -&gt; load_misc_binary chain and
stack overflow.

There's a similar problem with binfmt_script, and there's a sh_bang memner on
linux_binprm structure to handle this, but simply raising this in binfmt_misc
may break some setups when the interpreter of some misc binaries is a script.

So the proposal is to turn sh_bang into a bit, add a new one (the misc_bang)
and raise it in load_misc_binary.  After this, even if we set up the misc -&gt;
script -&gt; misc loop for binfmts one of them will step on its own bang and
exit.

Signed-off-by: Pavel Emelyanov &lt;xemul@openvz.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>
This can be triggered with root help only, but...

Register the ":text:E::txt::/root/cat.txt:' rule in binfmt_misc (by root) and
try launching the cat.txt file (by anyone) :) The result is - the endless
recursion in the load_misc_binary -&gt; open_exec -&gt; load_misc_binary chain and
stack overflow.

There's a similar problem with binfmt_script, and there's a sh_bang memner on
linux_binprm structure to handle this, but simply raising this in binfmt_misc
may break some setups when the interpreter of some misc binaries is a script.

So the proposal is to turn sh_bang into a bit, add a new one (the misc_bang)
and raise it in load_misc_binary.  After this, even if we set up the misc -&gt;
script -&gt; misc loop for binfmts one of them will step on its own bang and
exit.

Signed-off-by: Pavel Emelyanov &lt;xemul@openvz.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>[PATCH] sanitize handling of shared descriptor tables in failing execve()</title>
<updated>2008-04-25T13:23:53+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2008-04-22T09:11:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fd8328be874f4190a811c58cd4778ec2c74d2c05'/>
<id>fd8328be874f4190a811c58cd4778ec2c74d2c05</id>
<content type='text'>
* unshare_files() can fail; doing it after irreversible actions is wrong
  and de_thread() is certainly irreversible.
* since we do it unconditionally anyway, we might as well do it in do_execve()
  and save ourselves the PITA in binfmt handlers, etc.
* while we are at it, binfmt_som actually leaked files_struct on failure.

As a side benefit, unshare_files(), put_files_struct() and reset_files_struct()
become unexported.

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>
* unshare_files() can fail; doing it after irreversible actions is wrong
  and de_thread() is certainly irreversible.
* since we do it unconditionally anyway, we might as well do it in do_execve()
  and save ourselves the PITA in binfmt handlers, etc.
* while we are at it, binfmt_som actually leaked files_struct on failure.

As a side benefit, unshare_files(), put_files_struct() and reset_files_struct()
become unexported.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Convert files to UTF-8 and some cleanups</title>
<updated>2007-10-19T21:21:04+00:00</updated>
<author>
<name>Jan Engelhardt</name>
<email>jengelh@gmx.de</email>
</author>
<published>2007-10-19T21:21:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=96de0e252cedffad61b3cb5e05662c591898e69a'/>
<id>96de0e252cedffad61b3cb5e05662c591898e69a</id>
<content type='text'>
* Convert files to UTF-8.

  * Also correct some people's names
    (one example is Eißfeldt, which was found in a source file.
    Given that the author used an ß at all in a source file
    indicates that the real name has in fact a 'ß' and not an 'ss',
    which is commonly used as a substitute for 'ß' when limited to
    7bit.)

  * Correct town names (Goettingen -&gt; Göttingen)

  * Update Eberhard Mönkeberg's address (http://lkml.org/lkml/2007/1/8/313)

Signed-off-by: Jan Engelhardt &lt;jengelh@gmx.de&gt;
Signed-off-by: Adrian Bunk &lt;bunk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* Convert files to UTF-8.

  * Also correct some people's names
    (one example is Eißfeldt, which was found in a source file.
    Given that the author used an ß at all in a source file
    indicates that the real name has in fact a 'ß' and not an 'ss',
    which is commonly used as a substitute for 'ß' when limited to
    7bit.)

  * Correct town names (Goettingen -&gt; Göttingen)

  * Update Eberhard Mönkeberg's address (http://lkml.org/lkml/2007/1/8/313)

Signed-off-by: Jan Engelhardt &lt;jengelh@gmx.de&gt;
Signed-off-by: Adrian Bunk &lt;bunk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: variable length argument support</title>
<updated>2007-07-19T17:04:45+00:00</updated>
<author>
<name>Ollie Wild</name>
<email>aaw@google.com</email>
</author>
<published>2007-07-19T08:48:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b6a2fea39318e43fee84fa7b0b90d68bed92d2ba'/>
<id>b6a2fea39318e43fee84fa7b0b90d68bed92d2ba</id>
<content type='text'>
Remove the arg+env limit of MAX_ARG_PAGES by copying the strings directly from
the old mm into the new mm.

We create the new mm before the binfmt code runs, and place the new stack at
the very top of the address space.  Once the binfmt code runs and figures out
where the stack should be, we move it downwards.

It is a bit peculiar in that we have one task with two mm's, one of which is
inactive.

[a.p.zijlstra@chello.nl: limit stack size]
Signed-off-by: Ollie Wild &lt;aaw@google.com&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: &lt;linux-arch@vger.kernel.org&gt;
Cc: Hugh Dickins &lt;hugh@veritas.com&gt;
[bunk@stusta.de: unexport bprm_mm_init]
Signed-off-by: Adrian Bunk &lt;bunk@stusta.de&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>
Remove the arg+env limit of MAX_ARG_PAGES by copying the strings directly from
the old mm into the new mm.

We create the new mm before the binfmt code runs, and place the new stack at
the very top of the address space.  Once the binfmt code runs and figures out
where the stack should be, we move it downwards.

It is a bit peculiar in that we have one task with two mm's, one of which is
inactive.

[a.p.zijlstra@chello.nl: limit stack size]
Signed-off-by: Ollie Wild &lt;aaw@google.com&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: &lt;linux-arch@vger.kernel.org&gt;
Cc: Hugh Dickins &lt;hugh@veritas.com&gt;
[bunk@stusta.de: unexport bprm_mm_init]
Signed-off-by: Adrian Bunk &lt;bunk@stusta.de&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>Detach sched.h from mm.h</title>
<updated>2007-05-21T16:18:19+00:00</updated>
<author>
<name>Alexey Dobriyan</name>
<email>adobriyan@gmail.com</email>
</author>
<published>2007-05-20T21:22:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e8edc6e03a5c8562dc70a6d969f732bdb355a7e7'/>
<id>e8edc6e03a5c8562dc70a6d969f732bdb355a7e7</id>
<content type='text'>
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.

This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
   getting them indirectly

Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
   they don't need sched.h
b) sched.h stops being dependency for significant number of files:
   on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
   after patch it's only 3744 (-8.3%).

Cross-compile tested on

	all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
	alpha alpha-up
	arm
	i386 i386-up i386-defconfig i386-allnoconfig
	ia64 ia64-up
	m68k
	mips
	parisc parisc-up
	powerpc powerpc-up
	s390 s390-up
	sparc sparc-up
	sparc64 sparc64-up
	um-x86_64
	x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig

as well as my two usual configs.

Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&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>
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.

This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
   getting them indirectly

Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
   they don't need sched.h
b) sched.h stops being dependency for significant number of files:
   on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
   after patch it's only 3744 (-8.3%).

Cross-compile tested on

	all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
	alpha alpha-up
	arm
	i386 i386-up i386-defconfig i386-allnoconfig
	ia64 ia64-up
	m68k
	mips
	parisc parisc-up
	powerpc powerpc-up
	s390 s390-up
	sparc sparc-up
	sparc64 sparc64-up
	um-x86_64
	x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig

as well as my two usual configs.

Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
