Implement file posix capabilities.  This allows programs to be given a
subset of root's powers regardless of who runs them, without having to use
setuid and giving the binary all of root's powers.

This version works with Kaigai Kohei's userspace tools, found at
http://www.kaigai.gr.jp/index.php.  For more information on how to use this
patch, Chris Friedhoff has posted a nice page at
http://www.friedhoff.org/fscaps.html.

Changelog:
	Nov 27:
	Incorporate fixes from Andrew Morton
	(security-introduce-file-caps-tweaks and
	security-introduce-file-caps-warning-fix)
	Fix Kconfig dependency.
	Fix change signaling behavior when file caps are not compiled in.

	Nov 13:
	Integrate comments from Alexey: Remove CONFIG_ ifdef from
	capability.h, and use %zd for printing a size_t.

	Nov 13:
	Fix endianness warnings by sparse as suggested by Alexey
	Dobriyan.

	Nov 09:
	Address warnings of unused variables at cap_bprm_set_security
	when file capabilities are disabled, and simultaneously clean
	up the code a little, by pulling the new code into a helper
	function.

	Nov 08:
	For pointers to required userspace tools and how to use
	them, see http://www.friedhoff.org/fscaps.html.

	Nov 07:
	Fix the calculation of the highest bit checked in
	check_cap_sanity().

	Nov 07:
	Allow file caps to be enabled without CONFIG_SECURITY, since
	capabilities are the default.
	Hook cap_task_setscheduler when !CONFIG_SECURITY.
	Move capable(TASK_KILL) to end of cap_task_kill to reduce
	audit messages.

	Nov 05:
	Add secondary calls in selinux/hooks.c to task_setioprio and
	task_setscheduler so that selinux and capabilities with file
	cap support can be stacked.

	Sep 05:
	As Seth Arnold points out, uid checks are out of place
	for capability code.

	Sep 01:
	Define task_setscheduler, task_setioprio, cap_task_kill, and
	task_setnice to make sure a user cannot affect a process in which
	they called a program with some fscaps.

	One remaining question is the note under task_setscheduler: are we
	ok with CAP_SYS_NICE being sufficient to confine a process to a
	cpuset?

	It is a semantic change, as without fsccaps, attach_task doesn't
	allow CAP_SYS_NICE to override the uid equivalence check.  But since
	it uses security_task_setscheduler, which elsewhere is used where
	CAP_SYS_NICE can be used to override the uid equivalence check,
	fixing it might be tough.

	     task_setscheduler
		 note: this also controls cpuset:attach_task.  Are we ok with
		     CAP_SYS_NICE being used to confine to a cpuset?
	     task_setioprio
	     task_setnice
		 sys_setpriority uses this (through set_one_prio) for another
		 process.  Need same checks as setrlimit

	Aug 21:
	Updated secureexec implementation to reflect the fact that
	euid and uid might be the same and nonzero, but the process
	might still have elevated caps.

	Aug 15:
	Handle endianness of xattrs.
	Enforce capability version match between kernel and disk.
	Enforce that no bits beyond the known max capability are
	set, else return -EPERM.
	With this extra processing, it may be worth reconsidering
	doing all the work at bprm_set_security rather than
	d_instantiate.

	Aug 10:
	Always call getxattr at bprm_set_security, rather than
	caching it at d_instantiate.

[morgan@kernel.org: file-caps clean up for linux/capability.h]
[bunk@kernel.org: unexport cap_inode_killpriv]
Signed-off-by: NSerge E. Hallyn <serue@us.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Andrew Morgan <morgan@kernel.org>
Signed-off-by: NAndrew Morgan <morgan@kernel.org>
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For those who don't care about CONFIG_SECURITY.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert LSM into a static interface, as the ability to unload a security
module is not required by in-tree users and potentially complicates the
overall security architecture.

Needlessly exported LSM symbols have been unexported, to help reduce API
abuse.

Parameters for the capability and root_plug modules are now specified
at boot.

The SECURITY_FRAMEWORK_VERSION macro has also been removed.

In a nutshell, there is no safe way to unload an LSM.  The modular interface
is thus unecessary and broken infrastructure.  It is used only by out-of-tree
modules, which are often binary-only, illegal, abusive of the API and
dangerous, e.g.  silently re-vectoring SELinux.

[akpm@linux-foundation.org: cleanups]
[akpm@linux-foundation.org: USB Kconfig fix]
[randy.dunlap@oracle.com: fix LSM kernel-doc]
Signed-off-by: NJames Morris <jmorris@namei.org>
Acked-by: NChris Wright <chrisw@sous-sol.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Acked-by: NArjan van de Ven <arjan@infradead.org>
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add recommended section IDs to Documentation/DocBook/filesystems.tmpl
Signed-off-by: NRob Landley <rob@landley.net>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix two htmldocs build breaks, introduced by moving include/linux/usb_gadget.h to
include/linux/usb/gadget.h and combining resume.c and suspend.c into main.c in
drivers/base/power.
Signed-off-by: NRob Landley <rob@landley.net>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add Documentation/RCU/00-INDEX
Signed-off-by: NRob Landley <rob@landley.net>
Acked-by: NPaul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add recommended section ID tags to deviceiobook.tmpl

Because otherwise the link #anchors in the html vary from build to build.
Signed-off-by: NRob Landley <rob@landley.net>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc for sys_remap_file_pages() and add info to the 'prot' NOTE.
Rename __prot parameter to prot.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: NNick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch does the following cleanups for Documentation/vm/slabinfo.c:

	- Fix two memory leaks;
	- Constify some char pointers;
	- Use snprintf instead of sprintf in case of buffer overflow;
	- Fix some indentations;
	- Other little improvements.
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

min_free_pages is critical for correctness, document it as such.
Signed-off-by: NPavel Machek <pavel@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This cleans up kdump documentation a bit. Plus I do not think we want
to mention Linux trademark in _every_ file in documentation....
Signed-off-by: NPavel Machek <pavel@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A couple of updates haven't considered whether the documentation makes
sense as a whole any more.  Three changes here:

 - Remove the reference to the "DAC Addressing for Address Space Hungry
   Devices" section which was deleted by Jan Beulich.
 - Remove the comment about DMA_24BIT_MASK which became obsolete when
   Tobias Klauser changed the code to actually use DMA_24BIT_MASK.
 - Remove the section "64-bit DMA and DAC cycle support" since it's
   fully covered above, and contains a reference to the section deleted
   by Jan.
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add Documentation/power/00-INDEX
Signed-off-by: NRob Landley <rob@landley.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add two missing entries to Documentation/powerpc/00-INDEX
Signed-off-by: NRob Landley <rob@landley.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Two 00-INDEX files under Documentation/w1
Signed-off-by: NRob Landley <rob@landley.net>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add missing entries to Documentation/00-INDEX
Signed-off-by: NRob Landley <rob@landley.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The existing Documentation/SM501.txt gives no clue what the chip is or does,
so copy the description from Kconfig help text.
Acked-by: NBen Dooks <ben@simtec.co.uk>
Signed-off-by: NRob Landley <rob@landley.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds the "reset_devices" option (that's used only by one device
driver for now) to the recommended list of command line parameters for kdump.

Meaning (Documentation/kernel-parameters.txt):
    reset_devices   [KNL] Force drivers to reset the underlying device
                    during initialization.
Signed-off-by: NBernhard Walle <bwalle@suse.de>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch reflects the
http://git.kernel.org/?p=linux/kernel/git/horms/kexec-tools-testing.git;a=commit;h=b9c3648e690ad0dad12389659673206213a09760
change in kexec-tools-testing also now in the kernel documentation.
Signed-off-by: NBernhard Walle <bwalle@suse.de>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix typos in CONFIG_RELOCATABLE.  Use tab + 2 spaces for indentation on all
lines.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Bernhard Walle <bwalle@suse.de>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adapts the Documentation/kdump/kdump.txt file to express the fact
that the x86_64 kernel is now also relocatable.  This makes i386 and x86_64
now behave the same, simplifying the documentation.
Signed-off-by: NBernhard Walle <bwalle@suse.de>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NRobert P. J. Day <rpjday@mindspring.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Johannes Berg reports (Thanks!) that &struct names are not highlighted in
html output format when they are inside a DOC: block.

DOC: blocks were not escaped thru xml_escape() like other kernel-doc
comments were.  Fixed that.

However, that left a problem with <p> ($blankline_html) being processed
thru xml_escape(), converting it to &lt;p&gt;, which isn't good for the
generated html output (the <p> should remain unchanged), so this patch also
introduces the notion of "local" kernel-doc meta-characters
('\\\\mnemonic:'), which are converted to html just before writing the
stream to its output file.

Please report any problems that you (anyone) see in "highlighting" in any
output mode (text, man, html, xml).

Also update copyright to include me.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a 00-INDEX file to Documentation/telephony/
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Acked-by: NRob Landley <rob@landley.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a 00-INDEX file to Documentation/sysctl/
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Cc: Rob Landley <rob@landley.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a 00-INDEX file to Documentation/mips/
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Cc: Rob Landley <rob@landley.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Looks like the 00-INDEX file lost its parent directory in -rc6-mm1.
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds a 00-INDEX file to Documentation/vm/
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Acked-by: NRob Landley <rob@landley.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NDenis Cheng <crquan@gmail.com>
Cc: Rob Landley <rob@landley.net>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some documentation for "make headers_install".
Signed-off-by: NRob Landley <rob@landley.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch cleans up duplicate includes in
	Documentation/
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I'm going to be modifying nfsd_rename() shortly to support read-only bind
mounts.  This #ifdef is around the area I'm patching, and it starts to get
really ugly if I just try to add my new code by itself.  Using this little
helper makes things a lot cleaner to use.
Signed-off-by: NDave Hansen <haveblue@us.ibm.com>
Acked-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

First of all, this makes the structure jumping look a little bit cleaner.  So,
this stands alone as a tiny cleanup.  But, we also need 'mnt' by itself a few
more times later in this series, so this isn't _just_ a cleanup.
Signed-off-by: NDave Hansen <haveblue@us.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

may_open() calls vfs_permission() before it does checks for IS_RDONLY(inode).
It checks _again_ inside of vfs_permission().

The check inside of vfs_permission() is going away eventually.  With the
mnt_want/drop_write() functions, all of the r/o checks (except for this one)
are consistently done before calling permission().  Because of this, I'd like
to use permission() to hold a debugging check to make sure that the
mnt_want/drop_write() calls are actually being made.

So, to do this:
1. remove the IS_RDONLY() check from permission()
2. enforce that you must mnt_want_write() before
   even calling permission()
3. actually add the debugging check to permission()

We need to rearrange may_open() to do r/o checks before calling permission().
Here's the patch.
Signed-off-by: NDave Hansen <haveblue@us.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Why do we need r/o bind mounts?

This feature allows a read-only view into a read-write filesystem.  In the
process of doing that, it also provides infrastructure for keeping track of
the number of writers to any given mount.

This has a number of uses.  It allows chroots to have parts of filesystems
writable.  It will be useful for containers in the future because users may
have root inside a container, but should not be allowed to write to
somefilesystems.  This also replaces patches that vserver has had out of the
tree for several years.

It allows security enhancement by making sure that parts of your filesystem
read-only (such as when you don't trust your FTP server), when you don't want
to have entire new filesystems mounted, or when you want atime selectively
updated.  I've been using the following script to test that the feature is
working as desired.  It takes a directory and makes a regular bind and a r/o
bind mount of it.  It then performs some normal filesystem operations on the
three directories, including ones that are expected to fail, like creating a
file on the r/o mount.

This patch:

Some filesystems forego the vfs and may_open() and create their own 'struct
file's.

This patch creates a couple of helper functions which can be used by these
filesystems, and will provide a unified place which the r/o bind mount code
may patch.

Also, rename an existing, static-scope init_file() to a less generic name.
Signed-off-by: NDave Hansen <haveblue@us.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add PNP debug message when adding a device, remove similar PNPACPI message
with less information.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Hoist the struct pnp_dev alloc up into the function where it's used.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use dev_info() for a little consistency.  Changes this:

    pnp: 00:01: ioport range 0xf50-0xf58 has been reserved
    pnp: 00:01: ioport range 0x408-0x40f has been reserved
    pnp: 00:01: ioport range 0x900-0x903 has been reserved

to this:

    system 00:01: ioport range 0xf50-0xf58 has been reserved
    system 00:01: ioport range 0x408-0x40f has been reserved
    system 00:01: ioport range 0x900-0x903 has been reserved
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If we have the struct pnp_dev available, we can use dev_info(), dev_err(),
etc., to give a little more information and consistency.

[akpm@linux-foundation.org: fix warning]
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

No functional change; just return errors early instead of putting the main
part of the function inside an "if" statement.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>