The vm_flags introduced in 6d7825b1 ("mm/fremap.c: fix oops on error
path") is supposed to avoid a compiler warning about unitialized
vm_flags without changing the generated code.

However I am concerned that this is going to be very brittle, and fail
with some compiler versions. The failure could be either of:

- compiler could actually load vma->vm_flags before checking for the
  !vma condition, thus reintroducing the oops

- compiler could optimize out the !vma check, since the pointer just got
  dereferenced shortly before (so the compiler knows it can't be NULL!)

I propose reversing this part of the change and initializing vm_flags to 0
just to avoid the bogus uninitialized use warning.
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Tommi Rantala <tt.rantala@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull fix for hlist_entry_safe() regression from Paul McKenney:
 "This contains a single commit that fixes a regression in
  hlist_entry_safe().  This macro references its argument twice, which
  can cause NULL-pointer errors.  This commit applies a gcc statement
  expression, creating a temporary variable to avoid the double
  reference.  This has been posted to LKML at

    https://lkml.org/lkml/2013/3/9/75.

  Kudos to CAI Qian, whose testing uncovered this, to Eric Dumazet, who
  spotted root cause, and to Li Zefan, who tested this commit."

* 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
  list: Fix double fetch of pointer in hlist_entry_safe()

The current version of hlist_entry_safe() fetches the pointer twice,
once to test for NULL and the other to compute the offset back to the
enclosing structure.  This is OK for normal lock-based use because in
that case, the pointer cannot change.  However, when the pointer is
protected by RCU (as in "rcu_dereference(p)"), then the pointer can
change at any time.  This use case can result in the following sequence
of events:

1.	CPU 0 invokes hlist_entry_safe(), fetches the RCU-protected
	pointer as sees that it is non-NULL.

2.	CPU 1 invokes hlist_del_rcu(), deleting the entry that CPU 0
	just fetched a pointer to.  Because this is the last entry
	in the list, the pointer fetched by CPU 0 is now NULL.

3.	CPU 0 refetches the pointer, obtains NULL, and then gets a
	NULL-pointer crash.

This commit therefore applies gcc's "({ })" statement expression to
create a temporary variable so that the specified pointer is fetched
only once, avoiding the above sequence of events.  Please note that
it is the caller's responsibility to use rcu_dereference() as needed.
This allows RCU-protected uses to work correctly without imposing
any additional overhead on the non-RCU case.

Many thanks to Eric Dumazet for spotting root cause!
Reported-by: CAI Qian <caiqian@redhat.com>
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Li Zefan <lizefan@huawei.com>

Pull ext2, ext3, reiserfs, quota fixes from Jan Kara:
 "A fix for regression in ext2, and a format string issue in ext3.  The
  rest isn't too serious."

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  ext2: Fix BUG_ON in evict() on inode deletion
  reiserfs: Use kstrdup instead of kmalloc/strcpy
  ext3: Fix format string issues
  quota: add missing use of dq_data_lock in __dquot_initialize

Pull namespace bugfixes from Eric Biederman:
 "This tree includes a partial revert for "fs: Limit sys_mount to only
  request filesystem modules." When I added the new style module aliases
  to the filesystems I deleted the old ones.  A bad move.  It turns out
  that distributions like Arch linux use module aliases when
  constructing ramdisks.  Which meant ultimately that an ext3 filesystem
  mounted with ext4 would not result in the ext4 module being put into
  the ramdisk.

  The other change in this tree adds a handful of filesystem module
  alias I simply failed to add the first time.  Which inconvinienced a
  few folks using cifs.

  I don't want to inconvinience folks any longer than I have to so here
  are these trivial fixes."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  fs: Readd the fs module aliases.
  fs: Limit sys_mount to only request filesystem modules. (Part 3)

Merge misc fixes from Andrew Morton:

 - A bunch of fixes

 - Finish off the idr API conversions before someone starts to use the
   old interfaces again.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  idr: idr_alloc() shouldn't trigger lowmem warning when preloaded
  UAPI: fix endianness conditionals in M32R's asm/stat.h
  UAPI: fix endianness conditionals in linux/raid/md_p.h
  UAPI: fix endianness conditionals in linux/acct.h
  UAPI: fix endianness conditionals in linux/aio_abi.h
  decompressors: fix typo "POWERPC"
  mm/fremap.c: fix oops on error path
  idr: deprecate idr_pre_get() and idr_get_new[_above]()
  tidspbridge: convert to idr_alloc()
  zcache: convert to idr_alloc()
  mlx4: remove leftover idr_pre_get() call
  workqueue: convert to idr_alloc()
  nfsd: convert to idr_alloc()
  nfsd: remove unused get_new_stid()
  kernel/signal.c: use __ARCH_HAS_SA_RESTORER instead of SA_RESTORER
  signal: always clear sa_restorer on execve
  mm: remove_memory(): fix end_pfn setting
  include/linux/res_counter.h needs errno.h

GFP_NOIO is often used for idr_alloc() inside preloaded section as the
allocation mask doesn't really matter.  If the idr tree needs to be
expanded, idr_alloc() first tries to allocate using the specified
allocation mask and if it fails falls back to the preloaded buffer.  This
order prevent non-preloading idr_alloc() users from taking advantage of
preloading ones by using preload buffer without filling it shifting the
burden of allocation to the preload users.

Unfortunately, this allowed/expected-to-fail kmem_cache allocation ends up
generating spurious slab lowmem warning before succeeding the request from
the preload buffer.

This patch makes idr_layer_alloc() add __GFP_NOWARN to the first
kmem_cache attempt and try kmem_cache again w/o __GFP_NOWARN after
allocation from preload_buffer fails so that lowmem warning is generated
if not suppressed by the original @gfp_mask.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: David Teigland <teigland@redhat.com>
Tested-by: David Teigland <teigland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be
compared against __BYTE_ORDER in preprocessor conditionals where these are
exposed to userspace (that is they're not inside __KERNEL__ conditionals).

However, in the main kernel the norm is to check for
"defined(__XXX_ENDIAN)" rather than comparing against __BYTE_ORDER and
this has incorrectly leaked into the userspace headers.

The definition of struct stat64 in M32R's asm/stat.h is wrong in this way.
 Note that userspace will likely interpret the field order incorrectly as
the big-endian variant on little-endian machines - depending on header
inclusion order.

[!!!] NOTE [!!!]  This patch may adversely change the userspace API.  It might
be better to fix the ordering of st_blocks and __pad4 in struct stat64.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be
compared against __BYTE_ORDER in preprocessor conditionals where these are
exposed to userspace (that is they're not inside __KERNEL__ conditionals).

However, in the main kernel the norm is to check for
"defined(__XXX_ENDIAN)" rather than comparing against __BYTE_ORDER and
this has incorrectly leaked into the userspace headers.

The definition of struct mdp_superblock_s in linux/raid/md_p.h is wrong in
this way.  Note that userspace will likely interpret the ordering of the
fields incorrectly as the big-endian variant on a little-endian machines -
depending on header inclusion order.

[!!!] NOTE [!!!]  This patch may adversely change the userspace API.  It might
be better to fix the ordering of events_hi, events_lo, cp_events_hi and
cp_events_lo in struct mdp_superblock_s / typedef mdp_super_t.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be
compared against __BYTE_ORDER in preprocessor conditionals where these are
exposed to userspace (that is they're not inside __KERNEL__ conditionals).

However, in the main kernel the norm is to check for
"defined(__XXX_ENDIAN)" rather than comparing against __BYTE_ORDER and
this has incorrectly leaked into the userspace headers.

The definition of ACCT_BYTEORDER in linux/acct.h is wrong in this way.
Note that userspace will likely interpret this incorrectly as the
big-endian variant on little-endian machines - depending on header
inclusion order.

[!!!] NOTE [!!!]  This patch may adversely change the userspace API.  It might
be better to fix the value of ACCT_BYTEORDER.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be
compared against __BYTE_ORDER in preprocessor conditionals where these are
exposed to userspace (that is they're not inside __KERNEL__ conditionals).

However, in the main kernel the norm is to check for
"defined(__XXX_ENDIAN)" rather than comparing against __BYTE_ORDER and
this has incorrectly leaked into the userspace headers.

The definition of PADDED() in linux/aio_abi.h is wrong in this way.  Note
that userspace will likely interpret this and thus the order of fields in
struct iocb incorrectly as the little-endian variant on big-endian
machines - depending on header inclusion order.

[!!!] NOTE [!!!]  This patch may adversely change the userspace API.  It might
be better to fix the ordering of aio_key and aio_reserved1 in struct iocb.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 5dc49c75 ("decompressors: make the default XZ_DEC_* config
match the selected architecture") added

	default y if POWERPC

to lib/xz/Kconfig.  But there is no Kconfig symbol POWERPC.  The most
general Kconfig symbol for the powerpc architecture is PPC.  So let's
use that.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Lasse Collin <lasse.collin@tukaani.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If find_vma() fails, sys_remap_file_pages() will dereference `vma', which
contains NULL.  Fix it by checking the pointer.

(We could alternatively check for err==0, but this seems more direct)

(The vm_flags change is to squish a bogus used-uninitialised warning
without adding extra code).
Reported-by: Tommi Rantala <tt.rantala@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Now that all in-kernel users are converted to ues the new alloc
interface, mark the old interface deprecated.  We should be able to
remove these in a few releases.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

idr_get_new*() and friends are about to be deprecated.  Convert to the
new idr_alloc() interface.

There are some peculiarities and possible bugs in the converted
functions.  This patch preserves those.

* drv_insert_node_res_element() returns -ENOMEM on alloc failure,
  -EFAULT if id space is exhausted.  -EFAULT is at best misleading.

* drv_proc_insert_strm_res_element() is even weirder.  It returns
  -EFAULT if kzalloc() fails, -ENOMEM if idr preloading fails and
  -EPERM if id space is exhausted.  What's going on here?

* drv_proc_insert_strm_res_element() doesn't free *pstrm_res after
  failure.

Only compile tested.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Víctor Manuel Jáquez Leal <vjaquez@igalia.com>
Cc: Rene Sapiens <rene.sapiens@ti.com>
Cc: Armando Uribe <x0095078@ti.com>
Cc: Omar Ramirez Luna <omar.ramirez@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

idr_get_new*() and friends are about to be deprecated.  Convert to the
new idr_alloc() interface.

Only compile tested.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 6a920060 ("IB/mlx4: convert to idr_alloc()") forgot to remove
idr_pre_get() call in mlx4_ib_cm_paravirt_init().  It's unnecessary and
idr_pre_get() will soon be deprecated.  Remove it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jack Morgenstein <jackm@dev.mellanox.co.il>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

idr_get_new*() and friends are about to be deprecated.  Convert to the
new idr_alloc() interface.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

idr_get_new*() and friends are about to be deprecated.  Convert to the
new idr_alloc() interface.

Only compile-tested.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

get_new_stid() is no longer used since commit 3abdb607 ("nfsd4:
simplify idr allocation").  Remove it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

__ARCH_HAS_SA_RESTORER is the preferred conditional for use in 3.9 and
later kernels, per Kees.

Cc: Emese Revfy <re.emese@gmail.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Julien Tinnes <jln@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When the new signal handlers are set up, the location of sa_restorer is
not cleared, leaking a parent process's address space location to
children.  This allows for a potential bypass of the parent's ASLR by
examining the sa_restorer value returned when calling sigaction().

Based on what should be considered "secret" about addresses, it only
matters across the exec not the fork (since the VMAs haven't changed
until the exec).  But since exec sets SIG_DFL and keeps sa_restorer,
this is where it should be fixed.

Given the few uses of sa_restorer, a "set" function was not written
since this would be the only use.  Instead, we use
__ARCH_HAS_SA_RESTORER, as already done in other places.

Example of the leak before applying this patch:

  $ cat /proc/$$/maps
  ...
  7fb9f3083000-7fb9f3238000 r-xp 00000000 fd:01 404469 .../libc-2.15.so
  ...
  $ ./leak
  ...
  7f278bc74000-7f278be29000 r-xp 00000000 fd:01 404469 .../libc-2.15.so
  ...
  1 0 (nil) 0x7fb9f30b94a0
  2 4000000 (nil) 0x7f278bcaa4a0
  3 4000000 (nil) 0x7f278bcaa4a0
  4 0 (nil) 0x7fb9f30b94a0
  ...

[akpm@linux-foundation.org: use SA_RESTORER for backportability]
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Emese Revfy <re.emese@gmail.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Julien Tinnes <jln@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

remove_memory() calls walk_memory_range() with [start_pfn, end_pfn), where
end_pfn is exclusive in this range.  Therefore, end_pfn needs to be set to
the next page of the end address.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Wu Jianguo <wujianguo@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

alpha allmodconfig:

  In file included from mm/memcontrol.c:28:
  include/linux/res_counter.h: In function 'res_counter_set_limit':
  include/linux/res_counter.h:203: error: 'EBUSY' undeclared (first use in this function)
  include/linux/res_counter.h:203: error: (Each undeclared identifier is reported only once
  include/linux/res_counter.h:203: error: for each function it appears in.)

Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull USB fixes from Greg Kroah-Hartman:
 "Here are a number of tiny USB fixes and new USB device ids for your
  3.9 tree.

  The "largest" one here is a revert of a usb-storage patch that turned
  out to be incorrect, breaking existing users, which is never a good
  thing.  Everything else is pretty simple and small"

* tag 'usb-3.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (43 commits)
  USB: quatech2: only write to the tty if the port is open.
  qcserial: bind to DM/DIAG port on Gobi 1K devices
  USB: cdc-wdm: fix buffer overflow
  usb: serial: Add Rigblaster Advantage to device table
  qcaux: add Franklin U600
  usb: musb: core: fix possible build error with randconfig
  usb: cp210x new Vendor/Device IDs
  usb: gadget: pxa25x: fix disconnect reporting
  usb: dwc3: ep0: fix sparc64 build
  usb: c67x00 RetryCnt value in c67x00 TD should be 3
  usb: Correction to c67x00 TD data length mask
  usb: Makefile: fix drivers/usb/phy/ Makefile entry
  USB: added support for Cinterion's products AH6 and PLS8
  usb: gadget: fix omap_udc build errors
  USB: storage: fix Huawei mode switching regression
  USB: storage: in-kernel modeswitching is deprecated
  tools: usb: ffs-test: Fix build failure
  USB: option: add Huawei E5331
  usb: musb: omap2430: fix sparse warning
  usb: musb: omap2430: fix omap_musb_mailbox glue check again
  ...

Pull tty/serial fixes from Greg Kroah-Hartman:
 "Here are some tty/serial driver fixes for 3.9

  We finally mute the annoying WARN_ON that lots of people are hitting
  and it turns out isn't needed anymore.  Also add a few new device ids
  and a some other minor fixes."

* tag 'tty-3.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: serial: fix typo "SERIAL_S3C2412"
  serial: 8250: Keep 8250.<xxxx> module options functional after driver rename
  tty: serial: fix typo "ARCH_S5P6450"
  tty/8250_pnp: serial port detection regression since v3.7
  serial: bcm63xx_uart: fix compilation after "TTY: switch tty_insert_flip_char"
  serial: 8250_pci: add support for another kind of NetMos Technology PCI 9835 Multi-I/O Controller
  Fix 4 port and add support for 8 port 'Unknown' PCI serial port cards
  tty/serial: Add support for Altera serial port
  tty: serial: vt8500: Unneccessary duplicated clock code removed
  tty: serial: mpc5xxx: fix PSC clock name bug
  TTY: disable debugging warning

Pull staging tree fixes from Greg Kroah-Hartman:
 "Here are some drivers/staging and drivers/iio fixes for 3.9 (the two
  are still pretty intertwined, hence them coming both from my tree
  still.) Nothing major, just a few things that have been reported by
  users, all of these have been in linux-next for a while."

* tag 'staging-3.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: comedi: dt9812: use CR_CHAN() for channel number
  staging/vt6656: Fix too large integer constant warning on 32-bit
  staging: comedi: drivers: usbduxsigma.c: fix DMA buffers on stack
  staging: imx/drm: request irq only after adding the crtc
  staging: comedi: drivers: usbduxfast.c: fix for DMA buffers on stack
  staging: comedi: drivers: usbdux.c: fix DMA buffers on stack
  staging: vt6656: Fix oops on resume from suspend.
  iio:common:st_sensors fixed all warning messages about uninitialized variables
  iio: Fix build error seen if IIO_TRIGGER is defined but IIO_BUFFER is not
  iio/imu: inv_mpu6050 depends on IIO_BUFFER
  iio:ad5064: Initialize register cache correctly
  iio:ad5064: Fix off by one in DAC value range check
  iio:ad5064: Fix address of the second channel for ad5065/ad5045/ad5025

Don't allowing sharing the root directory with processes in a
different user namespace.  There doesn't seem to be any point, and to
allow it would require the overhead of putting a user namespace
reference in fs_struct (for permission checks) and incrementing that
reference count on practically every call to fork.

So just perform the inexpensive test of forbidding sharing fs_struct
acrosss processes in different user namespaces.  We already disallow
other forms of threading when unsharing a user namespace so this
should be no real burden in practice.

This updates setns, clone, and unshare to disallow multiple user
namespaces sharing an fs_struct.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The commit 2e124b4a removed the checks
that prevented qt2_process_read_urb() from trying to put chars into
ttys that weren't actually opened.  This resulted in 'tty is NULL'
warnings from flush_to_ldisc() when the device was used.

The devices use just one read urb for all ports.  As a result
qt2_process_read_urb() may be called with the current port set to a
port number that has not been opened.  Add a check if the port is open
before calling tty_flip_buffer_push().
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Turns out we just need altsetting 1 and then we can talk to it.
Signed-off-by: Dan Williams <dcbw@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 8e3dffc6 introduced a regression where deleting inode with
large extended attributes leads to triggering
  BUG_ON(inode->i_state != (I_FREEING | I_CLEAR))
in fs/inode.c:evict(). That happens because freeing of xattr block
dirtied the inode and it happened after clear_inode() has been called.

Fix the issue by moving removal of xattr block into ext2_evict_inode()
before clear_inode() call close to a place where data blocks are
truncated. That is also more logical place and removes surprising
requirement that ext2_free_blocks() mustn't dirty the inode.
Reported-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Fix kernel-doc warning in futex.c and convert 'Returns' to the new Return:
kernel-doc notation format.

  Warning(kernel/futex.c:2286): Excess function parameter 'clockrt' description in 'futex_wait_requeue_pi'

Fix one spello.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix new kernel-doc warnings in kernel/signal.c:

  Warning(kernel/signal.c:2689): No description found for parameter 'uset'
  Warning(kernel/signal.c:2689): Excess function parameter 'set' description in 'sys_rt_sigpending'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix new kernel-doc warnings in idr:

  Warning(include/linux/idr.h:113): No description found for parameter 'idr'
  Warning(include/linux/idr.h:113): Excess function parameter 'idp' description in 'idr_find'
  Warning(lib/idr.c:232): Excess function parameter 'id' description in 'sub_alloc'
  Warning(lib/idr.c:232): Excess function parameter 'id' description in 'sub_alloc'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull virtio rng buffix from Rusty Russell:
 "Simple virtio-rng fix."

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio: rng: disallow multiple device registrations, fixes crashes

Merge tag 'stable/for-linus-3.9-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen fixes from Konrad Rzeszutek Wilk:
 - Compile warnings and errors (one on x86, two on ARM)
 - WARNING in xen-pciback
 - Use the acpi_processor_get_performance_info instead of the 'register'
   version

* tag 'stable/for-linus-3.9-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/acpi: remove redundant acpi/acpi_drivers.h include
  xen: arm: mandate EABI and use generic atomic operations.
  acpi: Export the acpi_processor_get_performance_info
  xen/pciback: Don't disable a PCI device that is already disabled.

I had assumed that the only use of module aliases for filesystems
prior to "fs: Limit sys_mount to only request filesystem modules."
was in request_module.  It turns out I was wrong.  At least mkinitcpio
in Arch linux uses these aliases.

So readd the preexising aliases, to keep from breaking userspace.

Userspace eventually will have to follow and use the same aliases the
kernel does.  So at some point we may be delete these aliases without
problems.  However that day is not today.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

The buffer for responses must not overflow.
If this would happen, set a flag, drop the data and return
an error after user space has read all remaining data.
Signed-off-by: Oliver Neukum <oliver@neukum.org>
CC: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In commit 887cbce0 ("arch Kconfig: centralise ARCH_NO_VIRT_TO_BUS")
I introduced the config sybmol HAVE_VIRT_TO_BUS and selected that where
needed.  I am not sure what I was thinking.  Instead, just directly
select VIRT_TO_BUS where it is needed.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Looking at mm/process_vm_access.c:process_vm_rw() and comparing it to
compat_process_vm_rw() shows that the compatibility code requires an
explicit "access_ok()" check before calling
compat_rw_copy_check_uvector(). The same difference seems to appear when
we compare fs/read_write.c:do_readv_writev() to
fs/compat.c:compat_do_readv_writev().

This subtle difference between the compat and non-compat requirements
should probably be debated, as it seems to be error-prone. In fact,
there are two others sites that use this function in the Linux kernel,
and they both seem to get it wrong:

Now shifting our attention to fs/aio.c, we see that aio_setup_iocb()
also ends up calling compat_rw_copy_check_uvector() through
aio_setup_vectored_rw(). Unfortunately, the access_ok() check appears to
be missing. Same situation for
security/keys/compat.c:compat_keyctl_instantiate_key_iov().

I propose that we add the access_ok() check directly into
compat_rw_copy_check_uvector(), so callers don't have to worry about it,
and it therefore makes the compat call code similar to its non-compat
counterpart. Place the access_ok() check in the same location where
copy_from_user() can trigger a -EFAULT error in the non-compat code, so
the ABI behaviors are alike on both compat and non-compat.

While we are here, fix compat_do_readv_writev() so it checks for
compat_rw_copy_check_uvector() negative return values.

And also, fix a memory leak in compat_keyctl_instantiate_key_iov() error
handling.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>