instead of ad-hackery around need_reval_dot(), do the following:
set a flag (LOOKUP_JUMPED) in the beginning of path, on absolute
symlink traversal, on ".." and on procfs-style symlinks.  Clear on
normal components, leave unchanged on ".".  Non-nested callers of
link_path_walk() call handle_reval_path(), which checks that flag
is set and that fs does want the final revalidate thing, then does
->d_revalidate().  In link_path_walk() all the return_reval stuff
is gone.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

no need to do it in three places...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Actual dependency on whether we want RCU or not is in 3 small areas
(as it ought to be) and everything around those is the same in both
versions.  Since each function has only one caller and those callers
are on two sides of if (flags & LOOKUP_RCU), it's easier and cleaner
to merge them and pull the checks inside.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

New helper: path_lookupat().  Basically, what do_path_lookup() boils to
modulo -ECHILD/-ESTALE handler.  path_walk* family is gone; vfs_path_lookup()
is using link_path_walk() directly, do_path_lookup() and do_filp_open()
are using path_lookupat().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

all remaining callers pass LOOKUP_PARENT to it, so
flags argument can die; renamed to kern_path_parent()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

don't rely on pathname resolution ending up twice at the same point...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Fix for a dumb preadv()/pwritev() compat bug - unlike the native
variants, compat_... ones forget to check FMODE_P{READ,WRITE}, so e.g.
on pipe the native preadv() will fail with -ESPIPE and compat one will
act as readv() and succeed.  Not critical, but it's a clear bug with trivial
fix.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* 'media_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6:
  [media] mantis_pci: remove asm/pgtable.h include
  [media] tda829x: fix regression in probe functions
  [media] mceusb: don't claim multifunction device non-IR parts
  [media] nuvoton-cir: fix wake from suspend
  [media] cx18: Add support for Hauppauge HVR-1600 models with s5h1411
  [media] ivtv: Fix corrective action taken upon DMA ERR interrupt to avoid hang
  [media] cx25840: fix probing of cx2583x chips
  [media] cx23885: Remove unused 'err:' labels to quiet compiler warning
  [media] cx23885: Revert "Check for slave nack on all transactions"
  [media] DiB7000M: add pid filtering
  [media] Fix sysfs rc protocol lookup for rc-5-sz
  [media] au0828: fix VBI handling when in V4L2 streaming mode
  [media] ir-raw: Properly initialize the IR event (BZ#27202)
  [media] s2255drv: firmware re-loading changes
  [media] Fix double free of video_device in mem2mem_testdev
  [media] DM04/QQBOX memcpy to const char fix

This patch fixes an issue in OpenIPMI module where sometimes an ABORT command
is sent after sending an IPMI request to BMC causing the IPMI request to fail.
Signed-off-by: YiCheng Doe <yicheng.doe@hp.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Tom Mingarelli <thomas.mingarelli@hp.com>
Tested-by: Andy Cress <andy.cress@us.kontron.com>
Tested-by: Mika Lansirine <Mika.Lansirinne@stonesoft.com>
Tested-by: Brian De Wolf <bldewolf@csupomona.edu>
Cc: Jean Michel Audet <Jean-Michel.Audet@ca.Kontron.com>
Cc: Jozef Sudelsky <jozef.sudolsky@elbiahosting.sk>
Acked-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  fs/dcache: allow d_obtain_alias() to return unhashed dentries
  Check for immutable/append flag in fallocate path
  sysctl: the include of rcupdate.h is only needed in the kernel
  fat: fix d_revalidate oopsen on NFS exports
  jfs: fix d_revalidate oopsen on NFS exports
  ocfs2: fix d_revalidate oopsen on NFS exports
  gfs2: fix d_revalidate oopsen on NFS exports
  fuse: fix d_revalidate oopsen on NFS exports
  ceph: fix d_revalidate oopsen on NFS exports
  reiserfs xattr ->d_revalidate() shouldn't care about RCU
  /proc/self is never going to be invalidated...

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, UV: Initialize the broadcast assist unit base destination node id properly
  x86, numa: Fix numa_emulation code with memory-less node0
  x86, build: Make sure mkpiggy fails on read error

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix sched rt group scheduling when hierachy is enabled

* 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf symbols: Avoid resolving [kernel.kallsyms] to real path for buildid cache
  perf symbols: Fix vmlinux path when not using --symfs

This reverts commit 951f3512

    drm/i915: Do not handle backlight combination mode specially

since this commit introduced other regressions due to untouched LBPC
register, e.g. the backlight dimmed after resume.

In addition to the revert, this patch includes a fix for the original
issue (weird backlight levels) by removing the wrong bit shift for
computing the current backlight level.
Also, including typo fixes (lpbc -> lbpc).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=34524Acked-by: Indan Zupancic <indan@nul.nu>
Reviewed-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Without this patch, inodes are not promptly freed on last close of an
unlinked file by an nfs client:

	client$ mount -tnfs4 server:/export/ /mnt/
	client$ tail -f /mnt/FOO
	...
	server$ df -i /export
	server$ rm /export/FOO
	(^C the tail -f)
	server$ df -i /export
	server$ echo 2 >/proc/sys/vm/drop_caches
	server$ df -i /export

the df's will show that the inode is not freed on the filesystem until
the last step, when it could have been freed after killing the client's
tail -f. On-disk data won't be deallocated either, leading to possible
spurious ENOSPC.

This occurs because when the client does the close, it arrives in a
compound with a putfh and a close, processed like:

	- putfh: look up the filehandle.  The only alias found for the
	  inode will be DCACHE_UNHASHED alias referenced by the filp
	  this, so it creates a new DCACHE_DISCONECTED dentry and
	  returns that instead.
	- close: closes the existing filp, which is destroyed
	  immediately by dput() since it's DCACHE_UNHASHED.
	- end of the compound: release the reference
	  to the current filehandle, and dput() the new
	  DCACHE_DISCONECTED dentry, which gets put on the
	  unused list instead of being destroyed immediately.

Nick Piggin suggested fixing this by allowing d_obtain_alias to return
the unhashed dentry that is referenced by the filp, instead of making it
create a new dentry.

Leave __d_find_alias() alone to avoid changing behavior of other
callers.

Also nfsd doesn't need all the checks of __d_find_alias(); any dentry,
hashed or unhashed, disconnected or not, should work.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

In the fallocate path the kernel doesn't check for the immutable/append
flag. It's possible to have a race condition in this scenario: an
application open a file in read/write and it does something, meanwhile
root set the immutable flag on the file, the application at that point
can call fallocate with success. In addition, we don't allow to do any
unreserve operation on an append only file but only the reserve one.
Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Fixes this built error:

include/linux/sysctl.h:28: included file 'linux/rcupdate.h' is not exported
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

can't blindly check nd->flags in ->d_revalidate()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

can't blindly check nd->flags in ->d_revalidate()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

can't blindly check nd->flags in ->d_revalidate()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

can't blindly check nd->flags in ->d_revalidate()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

can't blindly check nd->flags in ->d_revalidate()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

can't blindly check nd->flags in ->d_revalidate()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... it returns an error unconditionally
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/pseries: Disable VPNH feature
  powerpc/iseries: Fix early init access to lppaca

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  net: don't allow CAP_NET_ADMIN to load non-netdev kernel modules

Fixes this build-check error:

  include/linux/sysctl.h:28: included file 'linux/rcupdate.h' is not exported
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Since a8f80e8f any process with
CAP_NET_ADMIN may load any module from /lib/modules/.  This doesn't mean
that CAP_NET_ADMIN is a superset of CAP_SYS_MODULE as modules are
limited to /lib/modules/**.  However, CAP_NET_ADMIN capability shouldn't
allow anybody load any module not related to networking.

This patch restricts an ability of autoloading modules to netdev modules
with explicit aliases.  This fixes CVE-2011-1019.

Arnd Bergmann suggested to leave untouched the old pre-v2.6.32 behavior
of loading netdev modules by name (without any prefix) for processes
with CAP_SYS_MODULE to maintain the compatibility with network scripts
that use autoloading netdev modules by aliases like "eth0", "wlan0".

Currently there are only three users of the feature in the upstream
kernel: ipip, ip_gre and sit.

    root@albatros:~# capsh --drop=$(seq -s, 0 11),$(seq -s, 13 34) --
    root@albatros:~# grep Cap /proc/$$/status
    CapInh:	0000000000000000
    CapPrm:	fffffff800001000
    CapEff:	fffffff800001000
    CapBnd:	fffffff800001000
    root@albatros:~# modprobe xfs
    FATAL: Error inserting xfs
    (/lib/modules/2.6.38-rc6-00001-g2bf4ca3/kernel/fs/xfs/xfs.ko): Operation not permitted
    root@albatros:~# lsmod | grep xfs
    root@albatros:~# ifconfig xfs
    xfs: error fetching interface information: Device not found
    root@albatros:~# lsmod | grep xfs
    root@albatros:~# lsmod | grep sit
    root@albatros:~# ifconfig sit
    sit: error fetching interface information: Device not found
    root@albatros:~# lsmod | grep sit
    root@albatros:~# ifconfig sit0
    sit0      Link encap:IPv6-in-IPv4
	      NOARP  MTU:1480  Metric:1

    root@albatros:~# lsmod | grep sit
    sit                    10457  0
    tunnel4                 2957  1 sit

For CAP_SYS_MODULE module loading is still relaxed:

    root@albatros:~# grep Cap /proc/$$/status
    CapInh:	0000000000000000
    CapPrm:	ffffffffffffffff
    CapEff:	ffffffffffffffff
    CapBnd:	ffffffffffffffff
    root@albatros:~# ifconfig xfs
    xfs: error fetching interface information: Device not found
    root@albatros:~# lsmod | grep xfs
    xfs                   745319  0

Reference: https://lkml.org/lkml/2011/2/24/203Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Kees Cook <kees.cook@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>

This feature triggers nasty races in the scheduler between the
rebuilding of the topology and the load balancing code, causing
the machine to hang.

Disable it for now until the races are fixed.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The combination of commit

8154c5d2 and
93c22703

Broke boot on iSeries.

The problem is that iSeries very early boot code, which generates
the device-tree and runs before our normal early initializations
does need access the lppaca's very early, before the PACA array is
initialized, and in fact even before the boot PACA has been
initialized (it contains all 0's at this stage).

However, the first patch above makes that code use the new
llpaca_of(cpu) accessor, which itself is changed by the second patch to
use the PACA array.

We fix that by reverting iSeries to directly dereferencing the array. In
addition, we fix all iterators in the iSeries code to always skip CPU
whose number is above 63 which is the maximum size of that array and
the maximum number of supported CPUs on these machines.

Additionally, we make sure the boot_paca is properly initialized
in our early startup code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

* 'for-2.6.38' of git://linux-nfs.org/~bfields/linux:
  nfsd: wrong index used in inner loop
  nfsd4: fix bad pointer on failure to find delegation
  NFSD: fix decode_cb_sequence4resok

* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
  watchdog: sbc_fitpc2_wdt, fix crash on systems without DMI_BOARD_NAME

* 'for-2639-rc7/i2c-fixes' of git://git.fluff.org/bjdooks/linux:
  i2c-eg20t: include slab.h for memory allocations
  i2c-ocores: Fix pointer type mismatch error
  i2c-omap: Program I2C_WE on OMAP4 to enable i2c wakeup

Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] pcc-cpufreq: don't load driver if get_freq fails during init.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
  mmc: fix CONFIG_MMC_UNSAFE_RESUME regression

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  nd->inode is not set on the second attempt in path_walk()
  unfuck proc_sysctl ->d_compare()
  minimal fix for do_filp_open() race

Some systems don't provide DMI_BOARD_NAME in their DMI tables. Avoid
crash in such situations in fitpc2_wdt_init.

The fix is to check if the dmi_get_system_info return value is NULL.

The oops:
BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff81253ae6>] strstr+0x26/0xa0
PGD 3966e067 PUD 39605067 PMD 0
Oops: 0000 [#1] SMP
last sysfs file: /sys/devices/system/cpu/cpu1/cache/index2/shared_cpu_map
CPU 1
Modules linked in: ...
Pid: 1748, comm: modprobe Not tainted 2.6.37-22-default #1 /Bochs
RIP: 0010:[<ffffffff81253ae6>]  [<ffffffff81253ae6>] strstr+0x26/0xa0
RSP: 0018:ffff88003ad73f18  EFLAGS: 00010206
RAX: 0000000000000000 RBX: 00000000ffffffed RCX: 00000000ffffffff
RDX: ffffffffa003f4cc RSI: ffffffffa003f4c2 RDI: 0000000000000000
...
CR2: 0000000000000000 CR3: 000000003b7ac000 CR4: 00000000000006e0
...
Process modprobe (pid: 1748, threadinfo ffff88003ad72000, task ffff88002e6365c0)
Stack: ...
Call Trace:
 [<ffffffffa004201f>] fitpc2_wdt_init+0x1f/0x13c [sbc_fitpc2_wdt]
 [<ffffffff810002da>] do_one_initcall+0x3a/0x170
...
Code: f3 c3 0f 1f 00 80 3e 00 53 48 89 f8 74 1b 48 89 f2 0f 1f 40 00 48 83 c2 01 80 3a 00 75 f7 49 89 d0 48 89 f8 49 29 f0 75 02 5b c3 <80> 3f 00 74 0e 0f 1f 44 00 00 48 83 c0 01 80 38 00 75 f7 49 89
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>