autofs: work around unhappy compat problem on x86-64

commit a32744d4abae24572eff7269bc17895c41bd0085 upstream.

When the autofs protocol version 5 packet type was added in commit
5c0a32fc2cd0 ("autofs4: add new packet type for v5 communications"), it
obvously tried quite hard to be word-size agnostic, and uses explicitly
sized fields that are all correctly aligned.

However, with the final "char name[NAME_MAX+1]" array at the end, the
actual size of the structure ends up being not very well defined:
because the struct isn't marked 'packed', doing a "sizeof()" on it will
align the size of the struct up to the biggest alignment of the members
it has.

And despite all the members being the same, the alignment of them is
different: a "__u64" has 4-byte alignment on x86-32, but native 8-byte
alignment on x86-64.  And while 'NAME_MAX+1' ends up being a nice round
number (256), the name[] array starts out a 4-byte aligned.

End result: the "packed" size of the structure is 300 bytes: 4-byte, but
not 8-byte aligned.

As a result, despite all the fields being in the same place on all
architectures, sizeof() will round up that size to 304 bytes on
architectures that have 8-byte alignment for u64.

Note that this is *not* a problem for 32-bit compat mode on POWER, since
there __u64 is 8-byte aligned even in 32-bit mode.  But on x86, 32-bit
and 64-bit alignment is different for 64-bit entities, and as a result
the structure that has exactly the same layout has different sizes.

So on x86-64, but no other architecture, we will just subtract 4 from
the size of the structure when running in a compat task.  That way we
will write the properly sized packet that user mode expects.

Not pretty.  Sadly, this very subtle, and unnecessary, size difference
has been encoded in user space that wants to read packets of *exactly*
the right size, and will refuse to touch anything else.

Reported-and-tested-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix autofs compile without CONFIG_COMPAT

commit 3c761ea05a8900a907f32b628611873f6bef24b2 upstream.

The autofs compat handling fix caused a compile failure when
CONFIG_COMPAT isn't defined.

Instead of adding random #ifdef'fery in autofs, let's just make the
compat helpers earlier to use: without CONFIG_COMPAT, is_compat_task()
just hardcodes to zero.

We could probably do something similar for a number of other cases where
we have #ifdef's in code, but this is the low-hanging fruit.

Reported-and-tested-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
regset: Prevent null pointer reference on readonly regsets

commit c8e252586f8d5de906385d8cf6385fee289a825e upstream.

The regset common infrastructure assumed that regsets would always
have .get and .set methods, but not necessarily .active methods.
Unfortunately people have since written regsets without .set methods.

Rather than putting in stub functions everywhere, handle regsets with
null .get or .set methods explicitly.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
regset: Return -EFAULT, not -EIO, on host-side memory fault

commit 5189fa19a4b2b4c3bec37c3a019d446148827717 upstream.

There is only one error code to return for a bad user-space buffer
pointer passed to a system call in the same address space as the
system call is executed, and that is EFAULT.  Furthermore, the
low-level access routines, which catch most of the faults, return
EFAULT already.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@hack.frob.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
genirq: Clear action->thread_mask if IRQ_ONESHOT is not set

commit 52abb700e16a9aa4cbc03f3d7f80206cbbc80680 upstream.

Xommit ac5637611(genirq: Unmask oneshot irqs when thread was not woken)
fails to unmask when a !IRQ_ONESHOT threaded handler is handled by
handle_level_irq.

This happens because thread_mask is or'ed unconditionally in
irq_wake_thread(), but for !IRQ_ONESHOT interrupts never cleared.  So
the check for !desc->thread_active fails and keeps the interrupt
disabled.

Keep the thread_mask zero for !IRQ_ONESHOT interrupts.

Document the thread_mask magic while at it.

Reported-and-tested-by: Sven Joachim <svenjoac@gmx.de>
Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mmc: sdhci-esdhc-imx: fix for mmc cards on i.MX5

commit 5b6b0ad6e572b32a641116aaa5f897ffebe31e44 upstream.

On i.MX53 we have to write a special SDHCI_CMD_ABORTCMD to the
SDHCI_TRANSFER_MODE register during a MMC_STOP_TRANSMISSION
command. This works for SD cards. However, with MMC cards
the MMC_SET_BLOCK_COUNT command is used instead, but this
needs the same handling. Fix MMC cards by testing for the
MMC_SET_BLOCK_COUNT command aswell. Tested on a custom i.MX53
board with a Transcend MMC+ card and eMMC.

The kernel started used MMC_SET_BLOCK_COUNT in 3.0, so this
is a regression for these boards introduced in 3.0; it should
go to 3.0/3.1/3.2-stable.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm: memcg: Correct unregistring of events attached to the same eventfd

commit 371528caec553785c37f73fa3926ea0de84f986f upstream.

There is an issue when memcg unregisters events that were attached to
the same eventfd:

- On the first call mem_cgroup_usage_unregister_event() removes all
  events attached to a given eventfd, and if there were no events left,
  thresholds->primary would become NULL;

- Since there were several events registered, cgroups core will call
  mem_cgroup_usage_unregister_event() again, but now kernel will oops,
  as the function doesn't expect that threshold->primary may be NULL.

That's a good question whether mem_cgroup_usage_unregister_event()
should actually remove all events in one go, but nowadays it can't
do any better as cftype->unregister_event callback doesn't pass
any private event-associated cookie. So, let's fix the issue by
simply checking for threshold->primary.

FWIW, w/o the patch the following oops may be observed:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
 IP: [<ffffffff810be32c>] mem_cgroup_usage_unregister_event+0x9c/0x1f0
 Pid: 574, comm: kworker/0:2 Not tainted 3.3.0-rc4+ #9 Bochs Bochs
 RIP: 0010:[<ffffffff810be32c>]  [<ffffffff810be32c>] mem_cgroup_usage_unregister_event+0x9c/0x1f0
 RSP: 0018:ffff88001d0b9d60  EFLAGS: 00010246
 Process kworker/0:2 (pid: 574, threadinfo ffff88001d0b8000, task ffff88001de91cc0)
 Call Trace:
  [<ffffffff8107092b>] cgroup_event_remove+0x2b/0x60
  [<ffffffff8103db94>] process_one_work+0x174/0x450
  [<ffffffff8103e413>] worker_thread+0x123/0x2d0

Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
NOMMU: Don't need to clear vm_mm when deleting a VMA

commit b94cfaf6685d691dc3fab023cf32f65e9b7be09c upstream.

Don't clear vm_mm in a deleted VMA as it's unnecessary and might
conceivably break the filesystem or driver VMA close routine.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cifs: fix dentry refcount leak when opening a FIFO on lookup

commit 5bccda0ebc7c0331b81ac47d39e4b920b198b2cd upstream.

The cifs code will attempt to open files on lookup under certain
circumstances. What happens though if we find that the file we opened
was actually a FIFO or other special file?

Currently, the open filehandle just ends up being leaked leading to
a dentry refcount mismatch and oops on umount. Fix this by having the
code close the filehandle on the server if it turns out not to be a
regular file. While we're at it, change this spaghetti if statement
into a switch too.

Reported-by: CAI Qian <caiqian@redhat.com>
Tested-by: CAI Qian <caiqian@redhat.com>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm: thp: fix BUG on mm->nr_ptes

commit 1c641e84719429bbfe62a95ed3545ee7fe24408f upstream.

Dave Jones reports a few Fedora users hitting the BUG_ON(mm->nr_ptes...)
in exit_mmap() recently.

Quoting Hugh's discovery and explanation of the SMP race condition:

  "mm->nr_ptes had unusual locking: down_read mmap_sem plus
   page_table_lock when incrementing, down_write mmap_sem (or mm_users
   0) when decrementing; whereas THP is careful to increment and
   decrement it under page_table_lock.

   Now most of those paths in THP also hold mmap_sem for read or write
   (with appropriate checks on mm_users), but two do not: when
   split_huge_page() is called by hwpoison_user_mappings(), and when
   called by add_to_swap().

   It's conceivable that the latter case is responsible for the
   exit_mmap() BUG_ON mm->nr_ptes that has been reported on Fedora."

The simplest way to fix it without having to alter the locking is to make
split_huge_page() a noop in nr_ptes terms, so by counting the preallocated
pagetables that exists for every mapped hugepage.  It was an arbitrary
choice not to count them and either way is not wrong or right, because
they are not used but they're still allocated.

Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
crypto: mv_cesa - fix final callback not ignoring input data

commit f8f54e190ddb4ed697036b60f5e2ae6dd45b801c upstream.

Broken by commit 6ef84509f3d439ed2d43ea40080643efec37f54f for users
passing a request with non-zero 'nbytes' field, like e.g. testmgr.

Signed-off-by: Phil Sutter <phil.sutter@viprinet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ASoC: dapm: Check for bias level when powering down

commit 7679e42ec833ed70aa34790a5f39dcb7e5bda4fe upstream.

Recent enhancements in the bias management means that we might not be
in standby when the CODEC is idle and can have active widgets without
being in full power mode but the shutdown functionality assumes these
things. Add checks for the bias level at each stage so that we don't
do transitions other than the ON->PREPARE->STANDBY->OFF ones that the
drivers are expecting.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bsg: fix sysfs link remove warning

commit 37b40adf2d1b4a5e51323be73ccf8ddcf3f15dd3 upstream.

We create "bsg" link if q->kobj.sd is not NULL, so remove it only
when the same condition is true.

Fixes:

WARNING: at fs/sysfs/inode.c:323 sysfs_hash_and_remove+0x2b/0x77()
sysfs: can not remove 'bsg', no directory
Call Trace:
  [<c0429683>] warn_slowpath_common+0x6a/0x7f
  [<c0537a68>] ? sysfs_hash_and_remove+0x2b/0x77
  [<c042970b>] warn_slowpath_fmt+0x2b/0x2f
  [<c0537a68>] sysfs_hash_and_remove+0x2b/0x77
  [<c053969a>] sysfs_remove_link+0x20/0x23
  [<c05d88f1>] bsg_unregister_queue+0x40/0x6d
  [<c0692263>] __scsi_remove_device+0x31/0x9d
  [<c069149f>] scsi_forget_host+0x41/0x52
  [<c0689fa9>] scsi_remove_host+0x71/0xe0
  [<f7de5945>] quiesce_and_remove_host+0x51/0x83 [usb_storage]
  [<f7de5a1e>] usb_stor_disconnect+0x18/0x22 [usb_storage]
  [<c06c29de>] usb_unbind_interface+0x4e/0x109
  [<c067a80f>] __device_release_driver+0x6b/0xa6
  [<c067a861>] device_release_driver+0x17/0x22
  [<c067a46a>] bus_remove_device+0xd6/0xe6
  [<c06785e2>] device_del+0xf2/0x137
  [<c06c101f>] usb_disable_device+0x94/0x1a0

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kprobes: adjust "fix a memory leak in function pre_handler_kretprobe()"

3.0.21's 603b63484725a6e88e4ae5da58716efd88154b1e directly used
the upstream patch, yet kprobes locking in 3.0.x uses spin_lock...()
rather than raw_spin_lock...().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hwmon: (pmbus_core) Fix maximum number of POUT alarm attributes

commit 7cb3c44fb1f7999e4c53b6a52de6bc25da6de079 upstream.

There are up to three POUT alarm attributes, not two, since cap_alarm was added.

Reported-by: Michele Petracca <mi.petracca@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/usbnet: avoid recursive locking in usbnet_stop()

commit 4231d47e6fe69f061f96c98c30eaf9fb4c14b96d upstream.

|kernel BUG at kernel/rtmutex.c:724!
|[<c029599c>] (rt_spin_lock_slowlock+0x108/0x2bc) from [<c01c2330>] (defer_bh+0x1c/0xb4)
|[<c01c2330>] (defer_bh+0x1c/0xb4) from [<c01c3afc>] (rx_complete+0x14c/0x194)
|[<c01c3afc>] (rx_complete+0x14c/0x194) from [<c01cac88>] (usb_hcd_giveback_urb+0xa0/0xf0)
|[<c01cac88>] (usb_hcd_giveback_urb+0xa0/0xf0) from [<c01e1ff4>] (musb_giveback+0x34/0x40)
|[<c01e1ff4>] (musb_giveback+0x34/0x40) from [<c01e2b1c>] (musb_advance_schedule+0xb4/0x1c0)
|[<c01e2b1c>] (musb_advance_schedule+0xb4/0x1c0) from [<c01e2ca8>] (musb_cleanup_urb.isra.9+0x80/0x8c)
|[<c01e2ca8>] (musb_cleanup_urb.isra.9+0x80/0x8c) from [<c01e2ed0>] (musb_urb_dequeue+0xec/0x108)
|[<c01e2ed0>] (musb_urb_dequeue+0xec/0x108) from [<c01cbb90>] (unlink1+0xbc/0xcc)
|[<c01cbb90>] (unlink1+0xbc/0xcc) from [<c01cc2ec>] (usb_hcd_unlink_urb+0x54/0xa8)
|[<c01cc2ec>] (usb_hcd_unlink_urb+0x54/0xa8) from [<c01c2a84>] (unlink_urbs.isra.17+0x2c/0x58)
|[<c01c2a84>] (unlink_urbs.isra.17+0x2c/0x58) from [<c01c2b44>] (usbnet_terminate_urbs+0x94/0x10c)
|[<c01c2b44>] (usbnet_terminate_urbs+0x94/0x10c) from [<c01c2d68>] (usbnet_stop+0x100/0x15c)
|[<c01c2d68>] (usbnet_stop+0x100/0x15c) from [<c020f718>] (__dev_close_many+0x94/0xc8)

defer_bh() takes the lock which is hold during unlink_urbs(). The safe
walk suggest that the skb will be removed from the list and this is done
by defer_bh() so it seems to be okay to drop the lock here.

Reported-by: AnÃ­bal Almeida Pinto <anibal.pinto@efacec.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dm io: fix discard support

commit 0c535e0d6f463365c29623350dbd91642363c39b upstream.

This patch fixes a crash by recognising discards in dm_io.

Currently dm_mirror can send REQ_DISCARD bios if running over a
discard-enabled device and without support in dm_io the system
crashes badly.

BUG: unable to handle kernel paging request at 00800000
IP:  __bio_add_page.part.17+0xf5/0x1e0
...
 bio_add_page+0x56/0x70
 dispatch_io+0x1cf/0x240 [dm_mod]
 ? km_get_page+0x50/0x50 [dm_mod]
 ? vm_next_page+0x20/0x20 [dm_mod]
 ? mirror_flush+0x130/0x130 [dm_mirror]
 dm_io+0xdc/0x2b0 [dm_mod]
...

Introduced in 2.6.38-rc1 by commit 5fc2ffeabb9ee0fc0e71ff16b49f34f0ed3d05b4
(dm raid1: support discard).

Signed-off-by: Milan Broz <mbroz@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dm raid: fix flush support

commit 0ca93de9b789e0eb05e103f0c04de72df13da73a upstream.

Fix dm-raid flush support.

Both md and dm have support for flush, but the dm-raid target
forgot to set the flag to indicate that flushes should be
passed on.  (Important for data integrity e.g. with writeback cache
enabled.)

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux 3.0.24
aio: fix io_setup/io_destroy race

commit 86b62a2cb4fc09037bbce2959d2992962396fd7f upstream.

Have ioctx_alloc() return an extra reference, so that caller would drop it
on success and not bother with re-grabbing it on failure exit.  The current
code is obviously broken - io_destroy() from another thread that managed
to guess the address io_setup() would've returned would free ioctx right
under us; gets especially interesting if aio_context_t * we pass to
io_setup() points to PROT_READ mapping, so put_user() fails and we end
up doing io_destroy() on kioctx another thread has just got freed...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>