Pandora Sourcecodes - pandora-kernel.git/log

ALSA: ak411x: Fix stall in work callback

commit 4161b4505f1690358ac0a9ee59845a7887336b21 upstream.

When ak4114 work calls its callback and the callback invokes
ak4114_reinit(), it stalls due to flush_delayed_work(). For avoiding
this, control the reentrance by introducing a refcount. Also
flush_delayed_work() is replaced with cancel_delayed_work_sync().

The exactly same bug is present in ak4113.c and fixed as well.

Reported-by: Pavel Hofman <pavel.hofman@ivitera.com>
Acked-by: Jaroslav Kysela <perex@perex.cz>
Tested-by: Pavel Hofman <pavel.hofman@ivitera.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
[bwh: Backported to 3.2: snd_ak411{3,4}_reinit were previously using
flush_delayed_work_sync() rather than flush_delayed_work()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ASoC: atmel_ssc_dai: fix start event for I2S mode

commit a43bd7e125143b875caae6d4f9938855b440faaf upstream.

According to the I2S specification information as following:
- WS = 0, channel 1 (left)
- WS = 1, channel 2 (right)
So, the start event should be TF/RF falling edge.

Reported-by: Songjun Wu <songjun.wu@atmel.com>
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

MIPS: IRQ: Fix disable_irq on CPU IRQs

commit a3e6c1eff54878506b2dddcc202df9cc8180facb upstream.

If the irq_chip does not define .irq_disable, any call to disable_irq
will defer disabling the IRQ until it fires while marked as disabled.
This assumes that the handler function checks for this condition, which
handle_percpu_irq does not. In this case, calling disable_irq leads to
an IRQ storm, if the interrupt fires while disabled.

This optimization is only useful when disabling the IRQ is slow, which
is not true for the MIPS CPU IRQ.

Disable this optimization by implementing .irq_disable and .irq_enable

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8949/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

x86: mm/fault: Fix semaphore imbalance

When backporting commit 33692f27597f ('vm: add VM_FAULT_SIGSEGV
handling support') I didn't notice that it depended on a recent change
to the locking context of mm_fault_error() (commit 7fb08eca4527,
'x86: mm: move mmap_sem unlock from mm_fault_error() to caller').
That isn't easily applicable to 3.2, so instead make sure we drop
mm->mmap_sem on the new branch of mm_fault_error().

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

PCI: quirks: Fix backport of quirk_io()

Commit 06cf35f903aa ('PCI: Handle read-only BARs on AMD CS553x
devices') added the function quirk_io() which calls
pcibios_bus_to_resource().

Prior to Linux 3.14, pcibios_bus_to_resource() takes a pointer to
struct pci_dev and looks up the device's bus itself, so we need
to pass dev not dev->bus.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

Linux 3.2.67

PCI: Handle read-only BARs on AMD CS553x devices

commit 06cf35f903aa6da0cc8d9f81e9bcd1f7e1b534bb upstream.

Some AMD CS553x devices have read-only BARs because of a firmware or
hardware defect.  There's a workaround in quirk_cs5536_vsa(), but it no
longer works after 36e8164882ca ("PCI: Restore detection of read-only
BARs").  Prior to 36e8164882ca, we filled in res->start; afterwards we
leave it zeroed out.  The quirk only updated the size, so the driver tried
to use a region starting at zero, which didn't work.

Expand quirk_cs5536_vsa() to read the base addresses from the BARs and
hard-code the sizes.

On Nix's system BAR 2's read-only value is 0x6200.  Prior to 36e8164882ca,
we interpret that as a 512-byte BAR based on the lowest-order bit set.  Per
datasheet sec 5.6.1, that BAR (MFGPT) requires only 64 bytes; use that to
avoid clearing any address bits if a platform uses only 64-byte alignment.

[bhelgaas: changelog, reduce BAR 2 size to 64]
Fixes: 36e8164882ca ("PCI: Restore detection of read-only BARs")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=85991#c4
Link: http://support.amd.com/TechDocs/31506_cs5535_databook.pdf
Link: http://support.amd.com/TechDocs/33238G_cs5536_db.pdf
Reported-and-tested-by: Nix <nix@esperi.org.uk>
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

KVM: x86: SYSENTER emulation is broken

commit f3747379accba8e95d70cec0eae0582c8c182050 upstream.

SYSENTER emulation is broken in several ways:
1. It misses the case of 16-bit code segments completely (CVE-2015-0239).
2. MSR_IA32_SYSENTER_CS is checked in 64-bit mode incorrectly (bits 0 and 1 can
still be set without causing #GP).
3. MSR_IA32_SYSENTER_EIP and MSR_IA32_SYSENTER_ESP are not masked in
legacy-mode.
4. There is some unneeded code.

Fix it.

Cc: stable@vger.linux.org
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

KVM: x86 emulator: reject SYSENTER in compatibility mode on AMD guests

commit 1a18a69b762374c423305772500f36eb8984ca52 upstream.

If the guest thinks it's an AMD, it will not have prepared the SYSENTER MSRs,
and if the guest executes SYSENTER in compatibility mode, it will fails.

Detect this condition and #UD instead, like the spec says.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

netfilter: conntrack: disable generic tracking for known protocols

commit db29a9508a9246e77087c5531e45b2c88ec6988b upstream.

Given following iptables ruleset:

-P FORWARD DROP
-A FORWARD -m sctp --dport 9 -j ACCEPT
-A FORWARD -p tcp --dport 80 -j ACCEPT
-A FORWARD -p tcp -m conntrack -m state ESTABLISHED,RELATED -j ACCEPT

One would assume that this allows SCTP on port 9 and TCP on port 80.
Unfortunately, if the SCTP conntrack module is not loaded, this allows
*all* SCTP communication, to pass though, i.e. -p sctp -j ACCEPT,
which we think is a security issue.

This is because on the first SCTP packet on port 9, we create a dummy
"generic l4" conntrack entry without any port information (since
conntrack doesn't know how to extract this information).

All subsequent packets that are unknown will then be in established
state since they will fallback to proto_generic and will match the
'generic' entry.

Our originally proposed version [1] completely disabled generic protocol
tracking, but Jozsef suggests to not track protocols for which a more
suitable helper is available, hence we now mitigate the issue for in
tree known ct protocol helpers only, so that at least NAT and direction
information will still be preserved for others.

[1] http://www.spinics.net/lists/netfilter-devel/msg33430.html

Joint work with Daniel Borkmann.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

splice: Apply generic position and size checks to each write

We need to check the position and size of file writes against various
limits, using generic_write_check(). This was not being done for
the splice write path. It was fixed upstream by commit 8d0207652cbe
("->splice_write() via ->write_iter()") but we can't apply that.

CVE-2014-7822

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

vfs: Fix vfsmount_lock imbalance in path_init()

When backporting commit 4023bfc9f351 ("be careful with nd->inode in
path_init() and follow_dotdot_rcu()"), I failed to account for the
vfsmount_lock that is used in 3.2 but not upstream. path_init() takes
the lock if performing RCU lookup, but must drop it if (and only if)
it subsequently fails.

Reported-by: nuxi@vault24.org
References: https://bugzilla.kernel.org/show_bug.cgi?id=92531
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Tested-by: nuxi@vault24.org

net/core: Handle csum for CHECKSUM_COMPLETE VXLAN forwarding

[ Upstream commit 2c26d34bbcc0b3f30385d5587aa232289e2eed8e ]

When using VXLAN tunnels and a sky2 device, I have experienced
checksum failures of the following type:

[ 4297.761899] eth0: hw csum failure
[...]
[ 4297.765223] Call Trace:
[ 4297.765224]  <IRQ>  [<ffffffff8172f026>] dump_stack+0x46/0x58
[ 4297.765235]  [<ffffffff8162ba52>] netdev_rx_csum_fault+0x42/0x50
[ 4297.765238]  [<ffffffff8161c1a0>] ? skb_push+0x40/0x40
[ 4297.765240]  [<ffffffff8162325c>] __skb_checksum_complete+0xbc/0xd0
[ 4297.765243]  [<ffffffff8168c602>] tcp_v4_rcv+0x2e2/0x950
[ 4297.765246]  [<ffffffff81666ca0>] ? ip_rcv_finish+0x360/0x360

These are reliably reproduced in a network topology of:

container:eth0 == host(OVS VXLAN on VLAN) == bond0 == eth0 (sky2) -> switch

When VXLAN encapsulated traffic is received from a similarly
configured peer, the above warning is generated in the receive
processing of the encapsulated packet.  Note that the warning is
associated with the container eth0.

        The skbs from sky2 have ip_summed set to CHECKSUM_COMPLETE, and
because the packet is an encapsulated Ethernet frame, the checksum
generated by the hardware includes the inner protocol and Ethernet
headers.

The receive code is careful to update the skb->csum, except in
__dev_forward_skb, as called by dev_forward_skb.  __dev_forward_skb
calls eth_type_trans, which in turn calls skb_pull_inline(skb, ETH_HLEN)
to skip over the Ethernet header, but does not update skb->csum when
doing so.

This patch resolves the problem by adding a call to
skb_postpull_rcsum to update the skb->csum after the call to
eth_type_trans.

Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

enic: fix rx skb checksum

[ Upstream commit 17e96834fd35997ca7cdfbf15413bcd5a36ad448 ]

Hardware always provides compliment of IP pseudo checksum. Stack expects
whole packet checksum without pseudo checksum if CHECKSUM_COMPLETE is set.

This causes checksum error in nf & ovs.

kernel: qg-19546f09-f2: hw csum failure
kernel: CPU: 9 PID: 0 Comm: swapper/9 Tainted: GF O-------------- 3.10.0-123.8.1.el7.x86_64 #1
kernel: Hardware name: Cisco Systems Inc UCSB-B200-M3/UCSB-B200-M3, BIOS B200M3.2.2.3.0.080820141339 08/08/2014
kernel: ffff881218f40000 df68243feb35e3a8 ffff881237a43ab8 ffffffff815e237b
kernel: ffff881237a43ad0 ffffffff814cd4ca ffff8829ec71eb00 ffff881237a43af0
kernel: ffffffff814c6232 0000000000000286 ffff8829ec71eb00 ffff881237a43b00
kernel: Call Trace:
kernel: <IRQ> [<ffffffff815e237b>] dump_stack+0x19/0x1b
kernel: [<ffffffff814cd4ca>] netdev_rx_csum_fault+0x3a/0x40
kernel: [<ffffffff814c6232>] __skb_checksum_complete_head+0x62/0x70
kernel: [<ffffffff814c6251>] __skb_checksum_complete+0x11/0x20
kernel: [<ffffffff8155a20c>] nf_ip_checksum+0xcc/0x100
kernel: [<ffffffffa049edc7>] icmp_error+0x1f7/0x35c [nf_conntrack_ipv4]
kernel: [<ffffffff814cf419>] ? netif_rx+0xb9/0x1d0
kernel: [<ffffffffa040eb7b>] ? internal_dev_recv+0xdb/0x130 [openvswitch]
kernel: [<ffffffffa04c8330>] nf_conntrack_in+0xf0/0xa80 [nf_conntrack]
kernel: [<ffffffff81509380>] ? inet_del_offload+0x40/0x40
kernel: [<ffffffffa049e302>] ipv4_conntrack_in+0x22/0x30 [nf_conntrack_ipv4]
kernel: [<ffffffff815005ca>] nf_iterate+0xaa/0xc0
kernel: [<ffffffff81509380>] ? inet_del_offload+0x40/0x40
kernel: [<ffffffff81500664>] nf_hook_slow+0x84/0x140
kernel: [<ffffffff81509380>] ? inet_del_offload+0x40/0x40
kernel: [<ffffffff81509dd4>] ip_rcv+0x344/0x380

Hardware verifies IP & tcp/udp header checksum but does not provide payload
checksum, use CHECKSUM_UNNECESSARY. Set it only if its valid IP tcp/udp packet.

Cc: Jiri Benc <jbenc@redhat.com>
Cc: Stefan Assmann <sassmann@redhat.com>
Reported-by: Sunil Choudhary <schoudha@redhat.com>
Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Reviewed-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

tg3: tg3_disable_ints using uninitialized mailbox value to disable interrupts

[ Upstream commit 05b0aa579397b734f127af58e401a30784a1e315 ]

During driver load in tg3_init_one, if the driver detects DMA activity before
intializing the chip tg3_halt is called. As part of tg3_halt interrupts are
disabled using routine tg3_disable_ints. This routine was using mailbox value
which was not initialized (default value is 0). As a result driver was writing
0x00000001 to pci config space register 0, which is the vendor id / device id.

This driver bug was exposed because of the commit a7877b17a667 (PCI: Check only
the Vendor ID to identify Configuration Request Retry). Also this issue is only
seen in older generation chipsets like 5722 because config space write to offset
0 from driver is possible. The newer generation chips ignore writes to offset 0.
Also without commit a7877b17a667, for these older chips when a GRC reset is
issued the Bootcode would reprogram the vendor id/device id, which is the reason
this bug was masked earlier.

Fixed by initializing the interrupt mailbox registers before calling tg3_halt.

Please queue for -stable.

Reported-by: Nils Holland <nholland@tisys.org>
Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Prashant Sreedharan <prashant@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

dcache: Fix locking bugs in backported "deal with deadlock in d_walk()"

Steven Rostedt reported:
> Porting -rt to the latest 3.2 stable tree I triggered this bug:
>
> =====================================
> [ BUG: bad unlock balance detected! ]
> -------------------------------------
> rm/1638 is trying to release lock (rcu_read_lock) at:
> [<c04fde6c>] rcu_read_unlock+0x0/0x23
> but there are no more locks to release!
>
> other info that might help us debug this:
> 2 locks held by rm/1638:
>  #0:  (&sb->s_type->i_mutex_key#9/1){+.+.+.}, at: [<c04f93eb>] do_rmdir+0x5f/0xd2
>  #1:  (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [<c04f9329>] vfs_rmdir+0x49/0xac
>
> stack backtrace:
> Pid: 1638, comm: rm Not tainted 3.2.66-test-rt96+ #2
> Call Trace:
>  [<c083f390>] ? printk+0x1d/0x1f
>  [<c0463cdf>] print_unlock_inbalance_bug+0xc3/0xcd
>  [<c04653a8>] lock_release_non_nested+0x98/0x1ec
>  [<c046228d>] ? trace_hardirqs_off_caller+0x18/0x90
>  [<c0456f1c>] ? local_clock+0x2d/0x50
>  [<c04fde6c>] ? d_hash+0x2f/0x2f
>  [<c04fde6c>] ? d_hash+0x2f/0x2f
>  [<c046568e>] lock_release+0x192/0x1ad
>  [<c04fde83>] rcu_read_unlock+0x17/0x23
>  [<c04ff344>] shrink_dcache_parent+0x227/0x270
>  [<c04f9348>] vfs_rmdir+0x68/0xac
>  [<c04f9424>] do_rmdir+0x98/0xd2
>  [<c04f03ad>] ? fput+0x1a3/0x1ab
>  [<c084dd42>] ? sysenter_exit+0xf/0x1a
>  [<c0465b58>] ? trace_hardirqs_on_caller+0x118/0x149
>  [<c04fa3e0>] sys_unlinkat+0x2b/0x35
>  [<c084dd13>] sysenter_do_call+0x12/0x12
>
>
>
>
> There's a path to calling rcu_read_unlock() without calling
> rcu_read_lock() in have_submounts().
>
> goto positive;
>
> positive:
> if (!locked && read_seqretry(&rename_lock, seq))
> goto rename_retry;
>
> rename_retry:
> rcu_read_unlock();
>
> in the above path, rcu_read_lock() is never done before calling
> rcu_read_unlock();

I reviewed locking contexts in all three functions that I changed when
backporting "deal with deadlock in d_walk()".  It's actually worse
than this:

- We don't hold this_parent->d_lock at the 'positive' label in
  have_submounts(), but it is unlocked after 'rename_retry'.
- There is an rcu_read_unlock() after the 'out' label in
  select_parent(), but it's not held at the 'goto out'.

Fix all three lock imbalances.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Tested-by: Steven Rostedt <rostedt@goodmis.org>

netfilter: ipset: small potential read beyond the end of buffer

commit 2196937e12b1b4ba139806d132647e1651d655df upstream.

We could be reading 8 bytes into a 4 byte buffer here. It seems
harmless but adding a check is the right thing to do and it silences a
static checker warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

KEYS: close race between key lookup and freeing

commit a3a8784454692dd72e5d5d34dcdab17b4420e74c upstream.

When a key is being garbage collected, it's key->user would get put before
the ->destroy() callback is called, where the key is removed from it's
respective tracking structures.

This leaves a key hanging in a semi-invalid state which leaves a window open
for a different task to try an access key->user. An example is
find_keyring_by_name() which would dereference key->user for a key that is
in the process of being garbage collected (where key->user was freed but
->destroy() wasn't called yet - so it's still present in the linked list).

This would cause either a panic, or corrupt memory.

Fixes CVE-2014-9529.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
[bwh: Backported to 3.2: adjust indentation]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

fsnotify: next_i is freed during fsnotify_unmount_inodes.

commit 6424babfd68dd8a83d9c60a5242d27038856599f upstream.

During file system stress testing on 3.10 and 3.12 based kernels, the
umount command occasionally hung in fsnotify_unmount_inodes in the
section of code:

                spin_lock(&inode->i_lock);
                if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) {
                        spin_unlock(&inode->i_lock);
                        continue;
                }

As this section of code holds the global inode_sb_list_lock, eventually
the system hangs trying to acquire the lock.

Multiple crash dumps showed:

The inode->i_state == 0x60 and i_count == 0 and i_sb_list would point
back at itself.  As this is not the value of list upon entry to the
function, the kernel never exits the loop.

To help narrow down problem, the call to list_del_init in
inode_sb_list_del was changed to list_del.  This poisons the pointers in
the i_sb_list and causes a kernel to panic if it transverse a freed
inode.

Subsequent stress testing paniced in fsnotify_unmount_inodes at the
bottom of the list_for_each_entry_safe loop showing next_i had become
free.

We believe the root cause of the problem is that next_i is being freed
during the window of time that the list_for_each_entry_safe loop
temporarily releases inode_sb_list_lock to call fsnotify and
fsnotify_inode_delete.

The code in fsnotify_unmount_inodes attempts to prevent the freeing of
inode and next_i by calling __iget.  However, the code doesn't do the
__iget call on next_i

if i_count == 0 or
if i_state & (I_FREEING | I_WILL_FREE)

The patch addresses this issue by advancing next_i in the above two cases
until we either find a next_i which we can __iget or we reach the end of
the list.  This makes the handling of next_i more closely match the
handling of the variable "inode."

The time to reproduce the hang is highly variable (from hours to days.) We
ran the stress test on a 3.10 kernel with the proposed patch for a week
without failure.

During list_for_each_entry_safe, next_i is becoming free causing
the loop to never terminate.  Advance next_i in those cases where
__iget is not done.

Signed-off-by: Jerry Hoemann <jerry.hoemann@hp.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Ken Helias <kenhelias@firemail.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jan Kara <jack@suse.cz>

x86, cpu, amd: Add workaround for family 16h, erratum 793

commit 3b56496865f9f7d9bcb2f93b44c63f274f08e3b6 upstream.

This adds the workaround for erratum 793 as a precaution in case not
every BIOS implements it.  This addresses CVE-2013-6885.

Erratum text:

[Revision Guide for AMD Family 16h Models 00h-0Fh Processors,
document 51810 Rev. 3.04 November 2013]

793 Specific Combination of Writes to Write Combined Memory Types and
Locked Instructions May Cause Core Hang

Description

Under a highly specific and detailed set of internal timing
conditions, a locked instruction may trigger a timing sequence whereby
the write to a write combined memory type is not flushed, causing the
locked instruction to stall indefinitely.

Potential Effect on System

Processor core hang.

Suggested Workaround

BIOS should set MSR
C001_1020[15] = 1b.

Fix Planned

No fix planned

[ hpa: updated description, fixed typo in MSR name ]

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20140114230711.GS29865@pd.tnic
Tested-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
[bwh: Backported to 3.2:
- Adjust filename
- Venkatesh Srinivas pointed out we should use {rd,wr}msrl_safe() to
   avoid crashing on KVM.  This was fixed upstream by commit 8f86a7373a1c
   ("x86, AMD: Convert to the new bit access MSR accessors") but that's too
   much trouble to backport.  Here we must use {rd,wr}msrl_amd_safe().]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Moritz Muehlenhoff <jmm@debian.org>
Cc: Venkatesh Srinivas <venkateshs@google.com>

s390/3215: fix tty output containing tabs

commit e512d56c799517f33b301d81e9a5e0ebf30c2d1e upstream.

git commit 37f81fa1f63ad38e16125526bb2769ae0ea8d332
"n_tty: do O_ONLCR translation as a single write"
surfaced a bug in the 3215 device driver. In combination this
broke tab expansion for tty ouput.

The cause is an asymmetry in the behaviour of tty3215_ops->write
vs tty3215_ops->put_char. The put_char function scans for '\t'
but the write function does not.

As the driver has logic for the '\t' expansion remove XTABS
from c_oflag of the initial termios as well.

Reported-by: Stephen Powell <zlinuxman@wowway.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ACPI / EC: Fix regression due to conflicting firmware behavior between Samsung and Acer.

commit 79149001105f18bd2285ada109f9229ea24a7571 upstream.

It is reported that Samsung laptops that need to poll events are broken by
the following commit:
Commit 3afcf2ece453e1a8c2c6de19cdf06da3772a1b08
Subject: ACPI / EC: Add support to disallow QR_EC to be issued when SCI_EVT isn't set

The behaviors of the 2 vendor firmwares are conflict:
1. Acer: OSPM shouldn't issue QR_EC unless SCI_EVT is set, firmware
automatically sets SCI_EVT as long as there is event queued up.
2. Samsung: OSPM should issue QR_EC whatever SCI_EVT is set, firmware
returns 0 when there is no event queued up.

This patch is a quick fix to distinguish the behaviors to make Acer
behavior only effective for Acer EC firmware so that the breakages on
Samsung EC firmware can be avoided.

Fixes: 3afcf2ece453 (ACPI / EC: Add support to disallow QR_EC to be issued ...)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=44161
Reported-and-tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[ rjw : Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Kamal Mostafa <kamal@canonical.com>

Revert "x86, 64bit, mm: Mark data/bss/brk to nx"

This reverts commit e105c8187b7101e8a8a54ac0218c9d9c9463c636 which
was commit 72212675d1c96f5db8ec6fb35701879911193158 upstream.

This caused suspend/resume to stop working on at least some systems -
specifically, the system would reboot when woken.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>

Revert "x86, mm: Set NX across entire PMD at boot"

This reverts commit a5c187d92d2ce30315f333b9dff33af832e8b443 which
was commit 45e2a9d4701d8c624d4a4bcdd1084eae31e92f58 upstream.

The previous commit caused suspend/resume to stop working on at least
some systems - specifically, the system would reboot when woken.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>

vm: make stack guard page errors return VM_FAULT_SIGSEGV rather than SIGBUS

commit 9c145c56d0c8a0b62e48c8d71e055ad0fb2012ba upstream.

The stack guard page error case has long incorrectly caused a SIGBUS
rather than a SIGSEGV, but nobody actually noticed until commit
fee7e49d4514 ("mm: propagate error from stack expansion even for guard
page") because that error case was never actually triggered in any
normal situations.

Now that we actually report the error, people noticed the wrong signal
that resulted. So far, only the test suite of libsigsegv seems to have
actually cared, but there are real applications that use libsigsegv, so
let's not wait for any of those to break.

Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

vm: add VM_FAULT_SIGSEGV handling support

commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2:
- Adjust filenames, context
- Drop arc, metag, nios2 and lustre changes
- For sh, patch both 32-bit and 64-bit implementations to use goto bad_area
- For s390, pass int_code and trans_exc_code as arguments to do_no_context()
   and do_sigsegv()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

net: sctp: fix slab corruption from use after free on INIT collisions

commit 600ddd6825543962fb807884169e57b580dba208 upstream.

When hitting an INIT collision case during the 4WHS with AUTH enabled, as
already described in detail in commit 1be9a950c646 ("net: sctp: inherit
auth_capable on INIT collisions"), it can happen that we occasionally
still remotely trigger the following panic on server side which seems to
have been uncovered after the fix from commit 1be9a950c646 ...

[  533.876389] BUG: unable to handle kernel paging request at 00000000ffffffff
[  533.913657] IP: [<ffffffff811ac385>] __kmalloc+0x95/0x230
[  533.940559] PGD 5030f2067 PUD 0
[  533.957104] Oops: 0000 [#1] SMP
[  533.974283] Modules linked in: sctp mlx4_en [...]
[  534.939704] Call Trace:
[  534.951833]  [<ffffffff81294e30>] ? crypto_init_shash_ops+0x60/0xf0
[  534.984213]  [<ffffffff81294e30>] crypto_init_shash_ops+0x60/0xf0
[  535.015025]  [<ffffffff8128c8ed>] __crypto_alloc_tfm+0x6d/0x170
[  535.045661]  [<ffffffff8128d12c>] crypto_alloc_base+0x4c/0xb0
[  535.074593]  [<ffffffff8160bd42>] ? _raw_spin_lock_bh+0x12/0x50
[  535.105239]  [<ffffffffa0418c11>] sctp_inet_listen+0x161/0x1e0 [sctp]
[  535.138606]  [<ffffffff814e43bd>] SyS_listen+0x9d/0xb0
[  535.166848]  [<ffffffff816149a9>] system_call_fastpath+0x16/0x1b

... or depending on the the application, for example this one:

[ 1370.026490] BUG: unable to handle kernel paging request at 00000000ffffffff
[ 1370.026506] IP: [<ffffffff811ab455>] kmem_cache_alloc+0x75/0x1d0
[ 1370.054568] PGD 633c94067 PUD 0
[ 1370.070446] Oops: 0000 [#1] SMP
[ 1370.085010] Modules linked in: sctp kvm_amd kvm [...]
[ 1370.963431] Call Trace:
[ 1370.974632]  [<ffffffff8120f7cf>] ? SyS_epoll_ctl+0x53f/0x960
[ 1371.000863]  [<ffffffff8120f7cf>] SyS_epoll_ctl+0x53f/0x960
[ 1371.027154]  [<ffffffff812100d3>] ? anon_inode_getfile+0xd3/0x170
[ 1371.054679]  [<ffffffff811e3d67>] ? __alloc_fd+0xa7/0x130
[ 1371.080183]  [<ffffffff816149a9>] system_call_fastpath+0x16/0x1b

With slab debugging enabled, we can see that the poison has been overwritten:

[  669.826368] BUG kmalloc-128 (Tainted: G        W     ): Poison overwritten
[  669.826385] INFO: 0xffff880228b32e50-0xffff880228b32e50. First byte 0x6a instead of 0x6b
[  669.826414] INFO: Allocated in sctp_auth_create_key+0x23/0x50 [sctp] age=3 cpu=0 pid=18494
[  669.826424]  __slab_alloc+0x4bf/0x566
[  669.826433]  __kmalloc+0x280/0x310
[  669.826453]  sctp_auth_create_key+0x23/0x50 [sctp]
[  669.826471]  sctp_auth_asoc_create_secret+0xcb/0x1e0 [sctp]
[  669.826488]  sctp_auth_asoc_init_active_key+0x68/0xa0 [sctp]
[  669.826505]  sctp_do_sm+0x29d/0x17c0 [sctp] [...]
[  669.826629] INFO: Freed in kzfree+0x31/0x40 age=1 cpu=0 pid=18494
[  669.826635]  __slab_free+0x39/0x2a8
[  669.826643]  kfree+0x1d6/0x230
[  669.826650]  kzfree+0x31/0x40
[  669.826666]  sctp_auth_key_put+0x19/0x20 [sctp]
[  669.826681]  sctp_assoc_update+0x1ee/0x2d0 [sctp]
[  669.826695]  sctp_do_sm+0x674/0x17c0 [sctp]

Since this only triggers in some collision-cases with AUTH, the problem at
heart is that sctp_auth_key_put() on asoc->asoc_shared_key is called twice
when having refcnt 1, once directly in sctp_assoc_update() and yet again
from within sctp_auth_asoc_init_active_key() via sctp_assoc_update() on
the already kzfree'd memory, which is also consistent with the observation
of the poison decrease from 0x6b to 0x6a (note: the overwrite is detected
at a later point in time when poison is checked on new allocation).

Reference counting of auth keys revisited:

Shared keys for AUTH chunks are being stored in endpoints and associations
in endpoint_shared_keys list. On endpoint creation, a null key is being
added; on association creation, all endpoint shared keys are being cached
and thus cloned over to the association. struct sctp_shared_key only holds
a pointer to the actual key bytes, that is, struct sctp_auth_bytes which
keeps track of users internally through refcounting. Naturally, on assoc
or enpoint destruction, sctp_shared_key are being destroyed directly and
the reference on sctp_auth_bytes dropped.

User space can add keys to either list via setsockopt(2) through struct
sctp_authkey and by passing that to sctp_auth_set_key() which replaces or
adds a new auth key. There, sctp_auth_create_key() creates a new sctp_auth_bytes
with refcount 1 and in case of replacement drops the reference on the old
sctp_auth_bytes. A key can be set active from user space through setsockopt()
on the id via sctp_auth_set_active_key(), which iterates through either
endpoint_shared_keys and in case of an assoc, invokes (one of various places)
sctp_auth_asoc_init_active_key().

sctp_auth_asoc_init_active_key() computes the actual secret from local's
and peer's random, hmac and shared key parameters and returns a new key
directly as sctp_auth_bytes, that is asoc->asoc_shared_key, plus drops
the reference if there was a previous one. The secret, which where we
eventually double drop the ref comes from sctp_auth_asoc_set_secret() with
intitial refcount of 1, which also stays unchanged eventually in
sctp_assoc_update(). This key is later being used for crypto layer to
set the key for the hash in crypto_hash_setkey() from sctp_auth_calculate_hmac().

To close the loop: asoc->asoc_shared_key is freshly allocated secret
material and independant of the sctp_shared_key management keeping track
of only shared keys in endpoints and assocs. Hence, also commit 4184b2a79a76
("net: sctp: fix memory leak in auth key management") is independant of
this bug here since it concerns a different layer (though same structures
being used eventually). asoc->asoc_shared_key is reference dropped correctly
on assoc destruction in sctp_association_free() and when active keys are
being replaced in sctp_auth_asoc_init_active_key(), it always has a refcount
of 1. Hence, it's freed prematurely in sctp_assoc_update(). Simple fix is
to remove that sctp_auth_key_put() from there which fixes these panics.

Fixes: 730fc3d05cd4 ("[SCTP]: Implete SCTP-AUTH parameter processing")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ALSA: seq-dummy: remove deadlock-causing events on close

commit 0767e95bb96d7fdddcd590fb809e6975d93aebc5 upstream.

When the last subscriber to a "Through" port has been removed, the
subscribed destination ports might still be active, so it would be
wrong to send "all sounds off" and "reset controller" events to them.
The proper place for such a shutdown would be the closing of the actual
MIDI port (and close_substream() in rawmidi.c already can do this).

This also fixes a deadlock when dummy_unuse() tries to send events to
its own port that is already locked because it is being freed.

Reported-by: Peter Billam <peter@www.pjb.com.au>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drm/i915: Only fence tiled region of object.

commit af1a7301c7cf8912dca03065d448c4437c5c239f upstream.

When creating a fence for a tiled object, only fence the area that
makes up the actual tiles.  The object may be larger than the tiled
area and if we allow those extra addresses to be fenced, they'll
get converted to addresses beyond where the object is mapped. This
opens up the possiblity of writes beyond the end of object.

To prevent this, we adjust the size of the fence to only encompass
the area that makes up the actual tiles.  The extra space is considered
un-tiled and now behaves as if it was a linear object.

Testcase: igt/gem_tiled_fence_overflow
Reported-by: Dan Hettena <danh@ghs.com>
Signed-off-by: Bob Paauwe <bob.j.paauwe@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
[bwh: Backported to 3.2:
- Adjust context, indentation
- Apply to both i965_write_fence_reg() and sandybridge_write_fence_reg(),
   which have been combined into one function upstream]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

USB: Add OTG PET device to TPL

commit e5dff0e80463cc3fa236e898ef1491b40be70b19 upstream.

OTG device shall support this device for allowing compliance automated testing.
The modification is derived from Pavankumar and Vijayavardhans' previous work.

Signed-off-by: Macpaul Lin <macpaul@gmail.com>
Cc: Pavankumar Kondeti <pkondeti@codeaurora.org>
Cc: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

usb-core bInterval quirk

commit cd83ce9e6195aa3ea15ab4db92892802c20df5d0 upstream.

This patch adds a usb quirk to support devices with interupt endpoints
and bInterval values expressed as microframes. The quirk causes the
parse endpoint function to modify the reported bInterval to a standards
conforming value.

There is currently code in the endpoint parser that checks for
bIntervals that are outside of the valid range (1-16 for USB 2+ high
speed and super speed interupt endpoints). In this case, the code assumes
the bInterval is being reported in 1ms frames. As well, the correction
is only applied if the original bInterval value is out of the 1-16 range.

With this quirk applied to the device, the bInterval will be
accurately adjusted from microframes to an exponent.

Signed-off-by: James P Michels III <james.p.michels@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

usb-storage/SCSI: blacklist FUA on JMicron 152d:2566 USB-SATA controller

commit bf5c4136fa5ce471bdbf4cf59a813e32755fd014 upstream.

It looks like FUA support is broken on JMicron 152d:2566 bridge:

[223159.885704] sd 7:0:0:0: [sdc] Write Protect is off
[223159.885706] sd 7:0:0:0: [sdc] Mode Sense: 47 00 10 08
[223159.885942] sd 7:0:0:0: [sdc] Write cache: enabled, read cache: enabled, supports DPO and FUA

[223283.691677] sd 7:0:0:0: [sdc]
[223283.691680] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[223283.691681] sd 7:0:0:0: [sdc]
[223283.691682] Sense Key : Illegal Request [current]
[223283.691684] sd 7:0:0:0: [sdc]
[223283.691685] Add. Sense: Invalid field in cdb
[223283.691686] sd 7:0:0:0: [sdc] CDB:
[223283.691687] Write(10): 2a 08 15 d0 83 0d 00 00 01 00
[223283.691690] blk_update_request: critical target error, dev sdc, sector 2927892584

This patch adds blacklist flag so that sd will not use FUA

Signed-off-by: Dmitry Nezhevenko <dion@dion.org.ua>
Cc: Phil Dibowitz <phil@ipom.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

nl80211: fix per-station group key get/del and memory leak

commit 0fa7b39131576dd1baa6ca17fca53c65d7f62249 upstream.

In case userspace attempts to obtain key information for or delete a
unicast key, this is currently erroneously rejected unless the driver
sets the WIPHY_FLAG_IBSS_RSN flag. Apparently enough drivers do so it
was never noticed.

Fix that, and while at it fix a potential memory leak: the error path
in the get_key() function was placed after allocating a message but
didn't free it - move it to a better place. Luckily admin permissions
are needed to call this operation.

Fixes: e31b82136d1ad ("cfg80211/mac80211: allow per-station GTKs")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

x86, tls: Interpret an all-zero struct user_desc as "no segment"

commit 3669ef9fa7d35f573ec9c0e0341b29251c2734a7 upstream.

The Witcher 2 did something like this to allocate a TLS segment index:

        struct user_desc u_info;
        bzero(&u_info, sizeof(u_info));
        u_info.entry_number = (uint32_t)-1;

        syscall(SYS_set_thread_area, &u_info);

Strictly speaking, this code was never correct.  It should have set
read_exec_only and seg_not_present to 1 to indicate that it wanted
to find a free slot without putting anything there, or it should
have put something sensible in the TLS slot if it wanted to allocate
a TLS entry for real.  The actual effect of this code was to
allocate a bogus segment that could be used to exploit espfix.

The set_thread_area hardening patches changed the behavior, causing
set_thread_area to return -EINVAL and crashing the game.

This changes set_thread_area to interpret this as a request to find
a free slot and to leave it empty, which isn't *quite* what the game
expects but should be close enough to keep it working.  In
particular, using the code above to allocate two segments will
allocate the same segment both times.

According to FrostbittenKing on Github, this fixes The Witcher 2.

If this somehow still causes problems, we could instead allocate
a limit==0 32-bit data segment, but that seems rather ugly to me.

Fixes: 41bdc78544b8 x86/tls: Validate TLS entries to protect espfix
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/0cb251abe1ff0958b8e468a9a9a905b80ae3a746.1421954363.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

Input: i8042 - add noloop quirk for Medion Akoya E7225 (MD98857)

commit 1d90d6d5522befa8efa1a7ea406be65cf865ded4 upstream.

Without this the aux port does not get detected, and consequently the touchpad
will not work.

With this patch the touchpad is detected:

$ dmesg | grep -E "(SYN|i8042|serio)"
pnp 00:03: Plug and Play ACPI device, IDs SYN1d22 PNP0f13 (active)
i8042: PNP: PS/2 Controller [PNP0303:PS2K,PNP0f13:PS2M] at 0x60,0x64 irq 1,12
serio: i8042 KBD port at 0x60,0x64 irq 1
serio: i8042 AUX port at 0x60,0x64 irq 12
input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input4
psmouse serio1: synaptics: Touchpad model: 1, fw: 8.1, id: 0x1e2b1, caps: 0xd00123/0x840300/0x126800, board id: 2863, fw id: 1473085
input: SynPS/2 Synaptics TouchPad as /devices/platform/i8042/serio1/input/input6

dmidecode excerpt for this laptop is:

Handle 0x0001, DMI type 1, 27 bytes
System Information
        Manufacturer: Medion
        Product Name: Akoya E7225
        Version: 1.0

Signed-off-by: Jochen Hein <jochen@jochen.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

x86, tls, ldt: Stop checking lm in LDT_empty

commit e30ab185c490e9a9381385529e0fd32f0a399495 upstream.

32-bit programs don't have an lm bit in their ABI, so they can't
reliably cause LDT_empty to return true without resorting to memset.
They shouldn't need to do this.

This should fix a longstanding, if minor, issue in all 64-bit kernels
as well as a potential regression in the TLS hardening code.

Fixes: 41bdc78544b8 x86/tls: Validate TLS entries to protect espfix
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/72a059de55e86ad5e2935c80aa91880ddf19d07c.1421954363.git.luto@amacapital.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

x86, hyperv: Mark the Hyper-V clocksource as being continuous

commit 32c6590d126836a062b3140ed52d898507987017 upstream.

The Hyper-V clocksource is continuous; mark it accordingly.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Acked-by: jasowang@redhat.com
Cc: gregkh@linuxfoundation.org
Cc: devel@linuxdriverproject.org
Cc: olaf@aepfle.de
Cc: apw@canonical.com
Link: http://lkml.kernel.org/r/1421108762-3331-1-git-send-email-kys@microsoft.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

libata: prevent HSM state change race between ISR and PIO

commit ce7514526742c0898b837d4395f515b79dfb5a12 upstream.

It is possible for ata_sff_flush_pio_task() to set ap->hsm_task_state to
HSM_ST_IDLE in between the time __ata_sff_port_intr() checks for HSM_ST_IDLE
and before it calls ata_sff_hsm_move() causing ata_sff_hsm_move() to BUG().

This problem is hard to reproduce making this patch hard to verify, but this
fix will prevent the race.

I have not been able to reproduce the problem, but here is a crash dump from
a 2.6.32 kernel.

On examining the ata port's state, its hsm_task_state field has a value of HSM_ST_IDLE:

crash> struct ata_port.hsm_task_state ffff881c1121c000
  hsm_task_state = 0

Normally, this should not be possible as ata_sff_hsm_move() was called from ata_sff_host_intr(),
which checks hsm_task_state and won't call ata_sff_hsm_move() if it has a HSM_ST_IDLE value.

PID: 11053  TASK: ffff8816e846cae0  CPU: 0   COMMAND: "sshd"
#0 [ffff88008ba03960] machine_kexec at ffffffff81038f3b
#1 [ffff88008ba039c0] crash_kexec at ffffffff810c5d92
#2 [ffff88008ba03a90] oops_end at ffffffff8152b510
#3 [ffff88008ba03ac0] die at ffffffff81010e0b
#4 [ffff88008ba03af0] do_trap at ffffffff8152ad74
#5 [ffff88008ba03b50] do_invalid_op at ffffffff8100cf95
#6 [ffff88008ba03bf0] invalid_op at ffffffff8100bf9b
    [exception RIP: ata_sff_hsm_move+317]
    RIP: ffffffff813a77ad  RSP: ffff88008ba03ca0  RFLAGS: 00010097
    RAX: 0000000000000000  RBX: ffff881c1121dc60  RCX: 0000000000000000
    RDX: ffff881c1121dd10  RSI: ffff881c1121dc60  RDI: ffff881c1121c000
    RBP: ffff88008ba03d00   R8: 0000000000000000   R9: 000000000000002e
    R10: 000000000001003f  R11: 000000000000009b  R12: ffff881c1121c000
    R13: 0000000000000000  R14: 0000000000000050  R15: ffff881c1121dd78
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
#7 [ffff88008ba03d08] ata_sff_host_intr at ffffffff813a7fbd
#8 [ffff88008ba03d38] ata_sff_interrupt at ffffffff813a821e
#9 [ffff88008ba03d78] handle_IRQ_event at ffffffff810e6ec0
>--- <IRQ stack> ---
    [exception RIP: pipe_poll+48]
    RIP: ffffffff81192780  RSP: ffff880f26d459b8  RFLAGS: 00000246
    RAX: 0000000000000000  RBX: ffff880f26d459c8  RCX: 0000000000000000
    RDX: 0000000000000001  RSI: 0000000000000000  RDI: ffff881a0539fa80
    RBP: ffffffff8100bb8e   R8: ffff8803b23324a0   R9: 0000000000000000
    R10: ffff880f26d45dd0  R11: 0000000000000008  R12: ffffffff8109b646
    R13: ffff880f26d45948  R14: 0000000000000246  R15: 0000000000000246
    ORIG_RAX: ffffffffffffff10  CS: 0010  SS: 0018
    RIP: 00007f26017435c3  RSP: 00007fffe020c420  RFLAGS: 00000206
    RAX: 0000000000000017  RBX: ffffffff8100b072  RCX: 00007fffe020c45c
    RDX: 00007f2604a3f120  RSI: 00007f2604a3f140  RDI: 000000000000000d
    RBP: 0000000000000000   R8: 00007fffe020e570   R9: 0101010101010101
    R10: 0000000000000000  R11: 0000000000000246  R12: 00007fffe020e5f0
    R13: 00007fffe020e5f4  R14: 00007f26045f373c  R15: 00007fffe020e5e0
    ORIG_RAX: 0000000000000017  CS: 0033  SS: 002b

Somewhere between the ata_sff_hsm_move() check and the ata_sff_host_intr() check, the value changed.
On examining the other cpus to see what else was running, another cpu was running the error handler
routines:

PID: 326    TASK: ffff881c11014aa0  CPU: 1   COMMAND: "scsi_eh_1"
#0 [ffff88008ba27e90] crash_nmi_callback at ffffffff8102fee6
#1 [ffff88008ba27ea0] notifier_call_chain at ffffffff8152d515
#2 [ffff88008ba27ee0] atomic_notifier_call_chain at ffffffff8152d57a
#3 [ffff88008ba27ef0] notify_die at ffffffff810a154e
#4 [ffff88008ba27f20] do_nmi at ffffffff8152b1db
#5 [ffff88008ba27f50] nmi at ffffffff8152aaa0
    [exception RIP: _spin_lock_irqsave+47]
    RIP: ffffffff8152a1ff  RSP: ffff881c11a73aa0  RFLAGS: 00000006
    RAX: 0000000000000001  RBX: ffff881c1121deb8  RCX: 0000000000000000
    RDX: 0000000000000246  RSI: 0000000000000020  RDI: ffff881c122612d8
    RBP: ffff881c11a73aa0   R8: ffff881c17083800   R9: 0000000000000000
    R10: 0000000000000000  R11: 0000000000000000  R12: ffff881c1121c000
    R13: 000000000000001f  R14: ffff881c1121dd50  R15: ffff881c1121dc60
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
>--- <NMI exception stack> ---
#6 [ffff881c11a73aa0] _spin_lock_irqsave at ffffffff8152a1ff
#7 [ffff881c11a73aa8] ata_exec_internal_sg at ffffffff81396fb5
#8 [ffff881c11a73b58] ata_exec_internal at ffffffff81397109
#9 [ffff881c11a73bd8] atapi_eh_request_sense at ffffffff813a34eb

Before it tried to acquire a spinlock, ata_exec_internal_sg() called ata_sff_flush_pio_task().
This function will set ap->hsm_task_state to HSM_ST_IDLE, and has no locking around setting this
value. ata_sff_flush_pio_task() can then race with the interrupt handler and potentially set
HSM_ST_IDLE at a fatal moment, which will trigger a kernel BUG.

v2: Fixup comment in ata_sff_flush_pio_task()

tj: Further updated comment.  Use ap->lock instead of shost lock and
    use the [un]lock_irq variant instead of the irqsave/restore one.

Signed-off-by: David Milburn <dmilburn@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

scripts/recordmcount.pl: There is no -m32 gcc option on Super-H anymore

commit 1caf6aaaa47471831d77c75f094d4e00ad1ec808 upstream.

Compiling SH with gcc-4.8 fails due to the -m32 option not being
supported.

From http://buildd.debian-ports.org/status/fetch.php?pkg=linux&arch=sh4&ver=3.16.7-ckt4-1&stamp=1421425783

      CC      init/main.o
    gcc-4.8: error: unrecognized command line option '-m32'
    ld: cannot find init/.tmp_mc_main.o: No such file or directory
    objcopy: 'init/.tmp_mx_main.o': No such file
    rm: cannot remove 'init/.tmp_mx_main.o': No such file or directory
    rm: cannot remove 'init/.tmp_mc_main.o': No such file or directory

Link: http://lkml.kernel.org/r/1421537778-29001-1-git-send-email-kernel@mkarcher.dialup.fu-berlin.de
Link: http://lkml.kernel.org/r/54BCBDD4.10102@physik.fu-berlin.de
Cc: Matt Fleming <matt@console-pimps.org>
Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Michael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

libata: allow sata_sil24 to opt-out of tag ordered submission

commit 72dd299d5039a336493993dcc63413cf31d0e662 upstream.

Ronny reports: https://bugzilla.kernel.org/show_bug.cgi?id=87101
    "Since commit 8a4aeec8d "libata/ahci: accommodate tag ordered
    controllers" the access to the harddisk on the first SATA-port is
    failing on its first access. The access to the harddisk on the
    second port is working normal.

    When reverting the above commit, access to both harddisks is working
    fine again."

Maintain tag ordered submission as the default, but allow sata_sil24 to
continue with the old behavior.

Cc: Tejun Heo <tj@kernel.org>
Reported-by: Ronny Hegewald <Ronny.Hegewald@online.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ALSA: usb-audio: Add mic volume fix quirk for Logitech Webcam C210

commit 6455931186bff407493135e74c5f32efd30860e2 upstream.

Signed-off-by: Jason Lee Cragg <jcragg@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

net: sctp: fix race for one-to-many sockets in sendmsg's auto associate

commit 2061dcd6bff8b774b4fac8b0739b6be3f87bc9f2 upstream.

I.e. one-to-many sockets in SCTP are not required to explicitly
call into connect(2) or sctp_connectx(2) prior to data exchange.
Instead, they can directly invoke sendmsg(2) and the SCTP stack
will automatically trigger connection establishment through 4WHS
via sctp_primitive_ASSOCIATE(). However, this in its current
implementation is racy: INIT is being sent out immediately (as
it cannot be bundled anyway) and the rest of the DATA chunks are
queued up for later xmit when connection is established, meaning
sendmsg(2) will return successfully. This behaviour can result
in an undesired side-effect that the kernel made the application
think the data has already been transmitted, although none of it
has actually left the machine, worst case even after close(2)'ing
the socket.

Instead, when the association from client side has been shut down
e.g. first gracefully through SCTP_EOF and then close(2), the
client could afterwards still receive the server's INIT_ACK due
to a connection with higher latency. This INIT_ACK is then considered
out of the blue and hence responded with ABORT as there was no
alive assoc found anymore. This can be easily reproduced f.e.
with sctp_test application from lksctp. One way to fix this race
is to wait for the handshake to actually complete.

The fix defers waiting after sctp_primitive_ASSOCIATE() and
sctp_primitive_SEND() succeeded, so that DATA chunks cooked up
from sctp_sendmsg() have already been placed into the output
queue through the side-effect interpreter, and therefore can then
be bundeled together with COOKIE_ECHO control chunks.

strace from example application (shortened):

socket(PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP) = 3
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(1)=[{"hello", 5}], msg_controllen=0, msg_flags=0}, 0) = 5
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(1)=[{"hello", 5}], msg_controllen=0, msg_flags=0}, 0) = 5
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(1)=[{"hello", 5}], msg_controllen=0, msg_flags=0}, 0) = 5
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(1)=[{"hello", 5}], msg_controllen=0, msg_flags=0}, 0) = 5
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(0)=[], msg_controllen=48, {cmsg_len=48, cmsg_level=0x84 /* SOL_??? */, cmsg_type=, ...},
           msg_flags=0}, 0) = 0 // graceful shutdown for SOCK_SEQPACKET via SCTP_EOF
close(3) = 0

tcpdump before patch (fooling the application):

22:33:36.306142 IP 192.168.1.114.41462 > 192.168.1.115.8888: sctp (1) [INIT] [init tag: 3879023686] [rwnd: 106496] [OS: 10] [MIS: 65535] [init TSN: 3139201684]
22:33:36.316619 IP 192.168.1.115.8888 > 192.168.1.114.41462: sctp (1) [INIT ACK] [init tag: 3345394793] [rwnd: 106496] [OS: 10] [MIS: 10] [init TSN: 3380109591]
22:33:36.317600 IP 192.168.1.114.41462 > 192.168.1.115.8888: sctp (1) [ABORT]

tcpdump after patch:

14:28:58.884116 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [INIT] [init tag: 438593213] [rwnd: 106496] [OS: 10] [MIS: 65535] [init TSN: 3092969729]
14:28:58.888414 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [INIT ACK] [init tag: 381429855] [rwnd: 106496] [OS: 10] [MIS: 10] [init TSN: 2141904492]
14:28:58.888638 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [COOKIE ECHO] , (2) [DATA] (B)(E) [TSN: 3092969729] [...]
14:28:58.893278 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [COOKIE ACK] , (2) [SACK] [cum ack 3092969729] [a_rwnd 106491] [#gap acks 0] [#dup tsns 0]
14:28:58.893591 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [DATA] (B)(E) [TSN: 3092969730] [...]
14:28:59.096963 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [SACK] [cum ack 3092969730] [a_rwnd 106496] [#gap acks 0] [#dup tsns 0]
14:28:59.097086 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [DATA] (B)(E) [TSN: 3092969731] [...] , (2) [DATA] (B)(E) [TSN: 3092969732] [...]
14:28:59.103218 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [SACK] [cum ack 3092969732] [a_rwnd 106486] [#gap acks 0] [#dup tsns 0]
14:28:59.103330 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [SHUTDOWN]
14:28:59.107793 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [SHUTDOWN ACK]
14:28:59.107890 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [SHUTDOWN COMPLETE]

Looks like this bug is from the pre-git history museum. ;)

Fixes: 08707d5482df ("lksctp-2_5_31-0_5_1.patch")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

gpio: sysfs: fix gpio attribute-creation race

commit ebbeba120ab2ec6ac5f3afc1425ec6ff0b77ad6f upstream.

Fix attribute-creation race with userspace by using the default group
to create also the contingent gpio device attributes.

Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[bwh: Backported to 3.2:
- Adjust filenames, context
- Use gpio_to_desc(), not gpiod_to_desc(), in gpio_is_visible()
- gpio_is_visible() must return mode_t]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

gpio: sysfs: fix gpio device-attribute leak

commit 0915e6feb38de8d3601819992a5bd050201a56fa upstream.

The gpio device attributes were never destroyed when the gpio was
unexported (or on export failures).

Use device_create_with_groups() to create the default device attributes
of the gpio class device. Note that this also fixes the
attribute-creation race with userspace for these attributes.

Remove contingent attributes in export error path and on unexport.

Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

Fix circular locking dependency (3.3-rc2)

commit 864533ceb6db336dead389577c102a8b792a121a upstream.

Hi,

On Wed, Feb 8, 2012 at 8:41 PM, Felipe Balbi <balbi@ti.com> wrote:
> Hi guys,
>
> I have just triggered the folllowing:
>
> [   84.860321] ======================================================
> [   84.860321] [ INFO: possible circular locking dependency detected ]
> [   84.860321] 3.3.0-rc2-00026-ge4e8a39 #474 Not tainted
> [   84.860321] -------------------------------------------------------
> [   84.860321] bash/949 is trying to acquire lock:
> [   84.860321]  (sysfs_lock){+.+.+.}, at: [<c0275358>] gpio_value_store+0x24/0xcc
> [   84.860321]
> [   84.860321] but task is already holding lock:
> [   84.860321]  (s_active#22){++++.+}, at: [<c016996c>] sysfs_write_file+0xdc/0x184
> [   84.911468]
> [   84.911468] which lock already depends on the new lock.
> [   84.911468]
> [   84.920043]
> [   84.920043] the existing dependency chain (in reverse order) is:
> [   84.920043]
> [   84.927886] -> #1 (s_active#22){++++.+}:
> [   84.927886]        [<c008f640>] check_prevs_add+0xdc/0x150
> [   84.927886]        [<c008fc18>] validate_chain.clone.24+0x564/0x694
> [   84.927886]        [<c0090cdc>] __lock_acquire+0x49c/0x980
> [   84.951660]        [<c0091838>] lock_acquire+0x98/0x100
> [   84.951660]        [<c016a8e8>] sysfs_deactivate+0xb0/0x100
> [   84.962982]        [<c016b1b4>] sysfs_addrm_finish+0x2c/0x6c
> [   84.962982]        [<c016b8bc>] sysfs_remove_dir+0x84/0x98
> [   84.962982]        [<c02590d8>] kobject_del+0x10/0x78
> [   84.974670]        [<c02c29e8>] device_del+0x140/0x170
> [   84.974670]        [<c02c2a24>] device_unregister+0xc/0x18
> [   84.985382]        [<c0276894>] gpio_unexport+0xbc/0xdc
> [   84.985382]        [<c02768c8>] gpio_free+0x14/0xfc
> [   85.001708]        [<c0276a28>] unexport_store+0x78/0x8c
> [   85.001708]        [<c02c5af8>] class_attr_store+0x18/0x24
> [   85.007293]        [<c0169990>] sysfs_write_file+0x100/0x184
> [   85.018981]        [<c0109d48>] vfs_write+0xb4/0x148
> [   85.018981]        [<c0109fd0>] sys_write+0x40/0x70
> [   85.018981]        [<c0013cc0>] ret_fast_syscall+0x0/0x3c
> [   85.035003]
> [   85.035003] -> #0 (sysfs_lock){+.+.+.}:
> [   85.035003]        [<c008f54c>] check_prev_add+0x680/0x698
> [   85.035003]        [<c008f640>] check_prevs_add+0xdc/0x150
> [   85.052093]        [<c008fc18>] validate_chain.clone.24+0x564/0x694
> [   85.052093]        [<c0090cdc>] __lock_acquire+0x49c/0x980
> [   85.052093]        [<c0091838>] lock_acquire+0x98/0x100
> [   85.069885]        [<c047e280>] mutex_lock_nested+0x3c/0x2f4
> [   85.069885]        [<c0275358>] gpio_value_store+0x24/0xcc
> [   85.069885]        [<c02c18dc>] dev_attr_store+0x18/0x24
> [   85.087158]        [<c0169990>] sysfs_write_file+0x100/0x184
> [   85.087158]        [<c0109d48>] vfs_write+0xb4/0x148
> [   85.098297]        [<c0109fd0>] sys_write+0x40/0x70
> [   85.098297]        [<c0013cc0>] ret_fast_syscall+0x0/0x3c
> [   85.109069]
> [   85.109069] other info that might help us debug this:
> [   85.109069]
> [   85.117462]  Possible unsafe locking scenario:
> [   85.117462]
> [   85.117462]        CPU0                    CPU1
> [   85.128417]        ----                    ----
> [   85.128417]   lock(s_active#22);
> [   85.128417]                                lock(sysfs_lock);
> [   85.128417]                                lock(s_active#22);
> [   85.142486]   lock(sysfs_lock);
> [   85.151794]
> [   85.151794]  *** DEADLOCK ***
> [   85.151794]
> [   85.151794] 2 locks held by bash/949:
> [   85.158020]  #0:  (&buffer->mutex){+.+.+.}, at: [<c01698b8>] sysfs_write_file+0x28/0x184
> [   85.170349]  #1:  (s_active#22){++++.+}, at: [<c016996c>] sysfs_write_file+0xdc/0x184
> [   85.170349]
> [   85.178588] stack backtrace:
> [   85.178588] [<c001b824>] (unwind_backtrace+0x0/0xf0) from [<c008de64>] (print_circular_bug+0x100/0x114)
> [   85.193023] [<c008de64>] (print_circular_bug+0x100/0x114) from [<c008f54c>] (check_prev_add+0x680/0x698)
> [   85.193023] [<c008f54c>] (check_prev_add+0x680/0x698) from [<c008f640>] (check_prevs_add+0xdc/0x150)
> [   85.212524] [<c008f640>] (check_prevs_add+0xdc/0x150) from [<c008fc18>] (validate_chain.clone.24+0x564/0x694)
> [   85.212524] [<c008fc18>] (validate_chain.clone.24+0x564/0x694) from [<c0090cdc>] (__lock_acquire+0x49c/0x980)
> [   85.233306] [<c0090cdc>] (__lock_acquire+0x49c/0x980) from [<c0091838>] (lock_acquire+0x98/0x100)
> [   85.233306] [<c0091838>] (lock_acquire+0x98/0x100) from [<c047e280>] (mutex_lock_nested+0x3c/0x2f4)
> [   85.242614] [<c047e280>] (mutex_lock_nested+0x3c/0x2f4) from [<c0275358>] (gpio_value_store+0x24/0xcc)
> [   85.261840] [<c0275358>] (gpio_value_store+0x24/0xcc) from [<c02c18dc>] (dev_attr_store+0x18/0x24)
> [   85.261840] [<c02c18dc>] (dev_attr_store+0x18/0x24) from [<c0169990>] (sysfs_write_file+0x100/0x184)
> [   85.271240] [<c0169990>] (sysfs_write_file+0x100/0x184) from [<c0109d48>] (vfs_write+0xb4/0x148)
> [   85.290008] [<c0109d48>] (vfs_write+0xb4/0x148) from [<c0109fd0>] (sys_write+0x40/0x70)
> [   85.298400] [<c0109fd0>] (sys_write+0x40/0x70) from [<c0013cc0>] (ret_fast_syscall+0x0/0x3c)
> -bash: echo: write error: Operation not permitted
>
> the way to trigger is:
>
> root@legolas:~# cd /sys/class/gpio/
> root@legolas:/sys/class/gpio# echo 2 > export
> root@legolas:/sys/class/gpio# echo 2 > unexport
> root@legolas:/sys/class/gpio# echo 2 > export
> root@legolas:/sys/class/gpio# cd gpio2/
> root@legolas:/sys/class/gpio/gpio2# echo 1 > value

Looks 'sysfs_lock' needn't to be held for unregister, so the patch below may
fix the problem.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

gpiolib: Refactor gpio_export

commit fc4e2514995d9cd7f3e1a67098ce65d72acf8ec7 upstream.

The gpio_export function uses nested if statements and the status
variable to handle the failure cases. This makes the function logic
difficult to follow. Refactor the code to abort immediately on failure
using goto. This makes the code slightly longer, but significantly
reduces the nesting and number of split lines and makes the code easier
to read.

Signed-off-by: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

gpio: sysfs: fix gpio-chip device-attribute leak

commit 121b6a79955a3a3fd7bbb9b8cb88d5b9dad6283d upstream.

The gpio-chip device attributes were never destroyed when the device was
removed.

Fix by using device_create_with_groups() to create the device attributes
of the chip class device.

Note that this also fixes the attribute-creation race with userspace.

Fixes: d8f388d8dc8d ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

driver core: Introduce device_create_groups

commit 39ef311204941ddd01ea2950d6220c8ccc710d15 upstream.

device_create_groups lets callers create devices as well as associated
sysfs attributes with a single call. This avoids race conditions seen
if sysfs attributes on new devices are created later.

[fixed up comment block placement and add checks for printk buffer
formats - gregkh]

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

sysfs.h: add ATTRIBUTE_GROUPS() macro

commit f2f37f58b1b933b06d6d84e80a31a1b500fb0db2 upstream.

To make it easier for driver subsystems to work with attribute groups,
create the ATTRIBUTE_GROUPS macro to remove some of the repetitive
typing for the most common use for attribute groups.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

can: dev: fix crtlmode_supported check

commit 9b1087aa5e86448fe6ad40a58964e35f3ba423d5 upstream.

When changing flags in the CAN drivers ctrlmode the provided new content has to
be checked whether the bits are allowed to be changed. The bits that are to be
changed are given as a bitfield in cm->mask. Therefore checking against
cm->flags is wrong as the content can hold any kind of values.

The iproute2 tool sets the bits in cm->mask and cm->flags depending on the
detected command line options. To be robust against bogus user space
applications additionally sanitize the provided flags with the provided mask.

Cc: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracing

commit 237d28db036e411f22c03cfd5b0f6dc2aa9bf3bc upstream.

If the function graph tracer traces a jprobe callback, the system will
crash. This can easily be demonstrated by compiling the jprobe
sample module that is in the kernel tree, loading it and running the
function graph tracer.

# modprobe jprobe_example.ko
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
# ls

The first two commands end up in a nice crash after the first fork.
(do_fork has a jprobe attached to it, so "ls" just triggers that fork)

The problem is caused by the jprobe_return() that all jprobe callbacks
must end with. The way jprobes works is that the function a jprobe
is attached to has a breakpoint placed at the start of it (or it uses
ftrace if fentry is supported). The breakpoint handler (or ftrace callback)
will copy the stack frame and change the ip address to return to the
jprobe handler instead of the function. The jprobe handler must end
with jprobe_return() which swaps the stack and does an int3 (breakpoint).
This breakpoint handler will then put back the saved stack frame,
simulate the instruction at the beginning of the function it added
a breakpoint to, and then continue on.

For function tracing to work, it hijakes the return address from the
stack frame, and replaces it with a hook function that will trace
the end of the call. This hook function will restore the return
address of the function call.

If the function tracer traces the jprobe handler, the hook function
for that handler will not be called, and its saved return address
will be used for the next function. This will result in a kernel crash.

To solve this, pause function tracing before the jprobe handler is called
and unpause it before it returns back to the function it probed.

Some other updates:

Used a variable "saved_sp" to hold kcb->jprobe_saved_sp. This makes the
code look a bit cleaner and easier to understand (various tries to fix
this bug required this change).

Note, if fentry is being used, jprobes will change the ip address before
the function graph tracer runs and it will not be able to trace the
function that the jprobe is probing.

Link: http://lkml.kernel.org/r/20150114154329.552437962@goodmis.org
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

gpio: fix memory and reference leaks in gpiochip_add error path

commit 5539b3c938d64a60cb1fc442ac3ce9263d52de0c upstream.

Memory allocated and references taken by of_gpiochip_add and
acpi_gpiochip_add were never released on errors in gpiochip_add (e.g.
failure to find free gpio range).

Fixes: 391c970c0dd1 ("of/gpio: add default of_xlate function if device
has a node pointer")
Fixes: 664e3e5ac64c ("gpio / ACPI: register to ACPI events
automatically")

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[bwh: Backported to 3.2:
- Move call to of_gpiochip_add() into conditional section rather
than rearranging gotos and labels which are in different places
here
- There's no ACPI support]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

crypto: add missing crypto module aliases

commit 3e14dcf7cb80b34a1f38b55bc96f02d23fdaaaaf upstream.

Commit 5d26a105b5a7 ("crypto: prefix module autoloading with "crypto-"")
changed the automatic module loading when requesting crypto algorithms
to prefix all module requests with "crypto-". This requires all crypto
modules to have a crypto specific module alias even if their file name
would otherwise match the requested crypto algorithm.

Even though commit 5d26a105b5a7 added those aliases for a vast amount of
modules, it was missing a few. Add the required MODULE_ALIAS_CRYPTO
annotations to those files to make them get loaded automatically, again.
This fixes, e.g., requesting 'ecb(blowfish-generic)', which used to work
with kernels v3.18 and below.

Also change MODULE_ALIAS() lines to MODULE_ALIAS_CRYPTO(). The former
won't work for crypto modules any more.

Fixes: 5d26a105b5a7 ("crypto: prefix module autoloading with "crypto-"")
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.2:
- Adjust filenames
- Drop changes to algorithms and drivers we don't have]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

crypto: include crypto- module prefix in template

commit 4943ba16bbc2db05115707b3ff7b4874e9e3c560 upstream.

This adds the module loading prefix "crypto-" to the template lookup
as well.

For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly
includes the "crypto-" prefix at every level, correctly rejecting "vfat":

net-pf-38
algif-hash
crypto-vfat(blowfish)
crypto-vfat(blowfish)-all
crypto-vfat

Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.2: drop changes to cmac and mcryptd which we don't have]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

crypto: prefix module autoloading with "crypto-"

commit 5d26a105b5a73e5635eae0629b42fa0a90e07b7b upstream.

This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:

https://lkml.org/lkml/2013/3/4/70

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.2:
- Adjust filenames
- Drop changes to algorithms and drivers we don't have
- Add aliases to generic C implementations that didn't need them before]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

mm: fix corner case in anon_vma endless growing prevention

commit b800c91a0517071156e772d4fb329ad33590da62 upstream.

Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas() ("kernel
BUG at mm/rmap.c:399!") caused by commit 7a3ef208e662 ("mm: prevent
endless growth of anon_vma hierarchy")

Anon_vma_clone() is usually called for a copy of source vma in
destination argument.  If source vma has anon_vma it should be already
in dst->anon_vma.  NULL in dst->anon_vma is used as a sign that it's
called from anon_vma_fork().  In this case anon_vma_clone() finds
anon_vma for reusing.

Vma_adjust() calls it differently and this breaks anon_vma reusing
logic: anon_vma_clone() links vma to old anon_vma and updates degree
counters but vma_adjust() overrides vma->anon_vma right after that.  As
a result final unlink_anon_vmas() decrements degree for wrong anon_vma.

This patch assigns ->anon_vma before calling anon_vma_clone().

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Reported-and-tested-by: Chris Clayton <chris2553@googlemail.com>
Reported-and-tested-by: Oded Gabbay <oded.gabbay@amd.com>
Reported-and-tested-by: Chih-Wei Huang <cwhuang@android-x86.org>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: vma_adjust() didn't use a variable to propagate
the error code from anon_vma_clone(); change that at the same time]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

mm: Don't count the stack guard page towards RLIMIT_STACK

commit 690eac53daff34169a4d74fc7bfbd388c4896abb upstream.

Commit fee7e49d4514 ("mm: propagate error from stack expansion even for
guard page") made sure that we return the error properly for stack
growth conditions. It also theorized that counting the guard page
towards the stack limit might break something, but also said "Let's see
if anybody notices".

Somebody did notice. Apparently android-x86 sets the stack limit very
close to the limit indeed, and including the guard page in the rlimit
check causes the android 'zygote' process problems.

So this adds the (fairly trivial) code to make the stack rlimit check be
against the actual real stack size, rather than the size of the vma that
includes the guard page.

Reported-and-tested-by: Chih-Wei Huang <cwhuang@android-x86.org>
Cc: Jay Foad <jay.foad@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

USB: console: fix potential use after free

commit 32a4bf2e81ec378e5925d4e069e0677a6c86a6ad upstream.

Use tty kref to release the fake tty in usb_console_setup to avoid use
after free if the underlying serial driver has acquired a reference.

Note that using the tty destructor release_one_tty requires some more
state to be initialised.

Fixes: 4a90f09b20f4 ("tty: usb-serial krefs")
Signed-off-by: Johan Hovold <johan@kernel.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

usb: gadget: udc: atmel: fix possible oops when unloading module

commit 5fb694f96e7c19e66b1c55124b98812e32e3efa5 upstream.

When unloading the module 'g_hid.ko', the urb request will be dequeued and the
completion routine will be excuted. If there is no urb packet, the urb request
will not be added to the endpoint queue and the completion routine pointer in
urb request is NULL.

Accessing to this NULL function pointer will cause the Oops issue reported
below.

Add the code to check if the urb request is in the endpoint queue
or not. If the urb request is not in the endpoint queue, a negative
error code will be returned.

Here is the Oops log:

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = dedf0000
[00000000] *pgd=3ede5831, *pte=00000000, *ppte=00000000
Internal error: Oops: 80000007 [#1] ARM
Modules linked in: g_hid(-) usb_f_hid libcomposite
CPU: 0 PID: 923 Comm: rmmod Not tainted 3.18.0+ #2
Hardware name: Atmel SAMA5 (Device Tree)
task: df6b1100 ti: dedf6000 task.ti: dedf6000
PC is at 0x0
LR is at usb_gadget_giveback_request+0xc/0x10
pc : [<00000000>]    lr : [<c02ace88>]    psr: 60000093
sp : dedf7eb0  ip : df572634  fp : 00000000
r10: 00000000  r9 : df52e210  r8 : 60000013
r7 : df6a9858  r6 : df52e210  r5 : df6a9858  r4 : df572600
r3 : 00000000  r2 : ffffff98  r1 : df572600  r0 : df6a9868
Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c53c7d  Table: 3edf0059  DAC: 00000015
Process rmmod (pid: 923, stack limit = 0xdedf6230)
Stack: (0xdedf7eb0 to 0xdedf8000)
7ea0:                                     00000000 c02adbbc df572580 deced608
7ec0: df572600 df6a9868 df572634 c02aed3c df577c00 c01b8608 00000000 df6be27c
7ee0: 00200200 00100100 bf0162f4 c000e544 dedf6000 00000000 00000000 bf010c00
7f00: bf0162cc bf00159c 00000000 df572980 df52e218 00000001 df5729b8 bf0031d0
[..]
[<c02ace88>] (usb_gadget_giveback_request) from [<c02adbbc>] (request_complete+0x64/0x88)
[<c02adbbc>] (request_complete) from [<c02aed3c>] (usba_ep_dequeue+0x70/0x128)
[<c02aed3c>] (usba_ep_dequeue) from [<bf010c00>] (hidg_unbind+0x50/0x7c [usb_f_hid])
[<bf010c00>] (hidg_unbind [usb_f_hid]) from [<bf00159c>] (remove_config.isra.6+0x98/0x9c [libcomposite])
[<bf00159c>] (remove_config.isra.6 [libcomposite]) from [<bf0031d0>] (__composite_unbind+0x34/0x98 [libcomposite])
[<bf0031d0>] (__composite_unbind [libcomposite]) from [<c02acee0>] (usb_gadget_remove_driver+0x50/0x78)
[<c02acee0>] (usb_gadget_remove_driver) from [<c02ad570>] (usb_gadget_unregister_driver+0x64/0x94)
[<c02ad570>] (usb_gadget_unregister_driver) from [<bf0160c0>] (hidg_cleanup+0x10/0x34 [g_hid])
[<bf0160c0>] (hidg_cleanup [g_hid]) from [<c0056748>] (SyS_delete_module+0x118/0x19c)
[<c0056748>] (SyS_delete_module) from [<c000e3c0>] (ret_fast_syscall+0x0/0x30)
Code: bad PC value

Signed-off-by: Songjun Wu <songjun.wu@atmel.com>
[nicolas.ferre@atmel.com: reworked the commit message]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Fixes: 914a3f3b3754 ("USB: add atmel_usba_udc driver")
Signed-off-by: Felipe Balbi <balbi@ti.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

usb: gadget: udc: atmel: fix possible IN hang issue

commit 6785a1034461c2d2c205215f63a50a740896e55b upstream.

When receive data, the RXRDY in status register set by hardware
after a new packet has been stored in the endpoint FIFO. When it
is copied from FIFO, this bit is cleared which make the FIFO can
be accessed again.

In the receive_data() function, this bit RXRDY has been cleared.
So, after the receive_data() function return, this bit should
not be cleared again, or else it may cause the accessing FIFO
corrupt, which will make the data loss.

Fixes: 914a3f3b3754 (USB: add atmel_usba_udc driver)
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

usb: gadget: udc: atmel: change setting for DMA

commit f40afdddeb6c54ffd1e2920a5e93e363d6748db6 upstream.

According to the datasheet, when transfer using DMA, the control
setting for IN packet only need END_BUF_EN, END_BUF_IE, CH_EN,
while for OUT packet, need more two bits END_TR_EN and END_TR_IE
to be configured.

Fixes: 914a3f3b3754 (USB: add atmel_usba_udc driver)
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

OHCI: add a quirk for ULi M5237 blocking on reset

commit 56abcab833fafcfaeb2f5b25e0364c1dec45f53e upstream.

Commit 8dccddbc2368 ("OHCI: final fix for NVIDIA problems (I hope)")
introduced into 3.1.9 broke boot on e.g. Freescale P2020DS development
board. The code path that was previously specific to NVIDIA controllers
had then become taken for all chips.

However, the M5237 installed on the board wedges solid when accessing
its base+OHCI_FMINTERVAL register, making it impossible to boot any
kernel newer than 3.1.8 on this particular and apparently other similar
machines.

Don't readl() and writel() base+OHCI_FMINTERVAL on PCI ID 10b9:5237.

The patch is suitable for the -next tree as well as all maintained
kernels up to 3.2 inclusive.

Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

HID: roccat: potential out of bounds in pyra_sysfs_write_settings()

commit 606185b20caf4c57d7e41e5a5ea4aff460aef2ab upstream.

This is a static checker fix. We write some binary settings to the
sysfs file. One of the settings is the "->startup_profile". There
isn't any checking to make sure it fits into the
pyra->profile_settings[] array in the profile_activated() function.

I added a check to pyra_sysfs_write_settings() in both places because
I wasn't positive that the other callers were correct.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
[bwh: Backported to 3.2: pyra_sysfs_write_settings() doesn't define a
settings variable, so write the cast-expression inline]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

mm: protect set_page_dirty() from ongoing truncation

commit 2d6d7f98284648c5ed113fe22a132148950b140f upstream.

Tejun, while reviewing the code, spotted the following race condition
between the dirtying and truncation of a page:

__set_page_dirty_nobuffers()       __delete_from_page_cache()
  if (TestSetPageDirty(page))
                                     page->mapping = NULL
     if (PageDirty())
       dec_zone_page_state(page, NR_FILE_DIRTY);
       dec_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
    if (page->mapping)
      account_page_dirtied(page)
        __inc_zone_page_state(page, NR_FILE_DIRTY);
__inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);

which results in an imbalance of NR_FILE_DIRTY and BDI_RECLAIMABLE.

Dirtiers usually lock out truncation, either by holding the page lock
directly, or in case of zap_pte_range(), by pinning the mapcount with
the page table lock held.  The notable exception to this rule, though,
is do_wp_page(), for which this race exists.  However, do_wp_page()
already waits for a locked page to unlock before setting the dirty bit,
in order to prevent a race where clear_page_dirty() misses the page bit
in the presence of dirty ptes.  Upgrade that wait to a fully locked
set_page_dirty() to also cover the situation explained above.

Afterwards, the code in set_page_dirty() dealing with a truncation race
is no longer needed.  Remove it.

Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2:
- Adjust context
- Use VM_BUG_ON() rather than VM_BUG_ON_PAGE()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

mm: remove unused arg of set_page_dirty_balance()

commit ed6d7c8e578331cad594ee70d60e2e146b5dce7b upstream.

There's only one caller of set_page_dirty_balance() and that will call it
with page_mkwrite == 0.

The page_mkwrite argument was unused since commit b827e496c893 "mm: close
page_mkwrite races".

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

mm: prevent endless growth of anon_vma hierarchy

commit 7a3ef208e662f4b63d43a23f61a64a129c525bbc upstream.

Constantly forking task causes unlimited grow of anon_vma chain.  Each
next child allocates new level of anon_vmas and links vma to all
previous levels because pages might be inherited from any level.

This patch adds heuristic which decides to reuse existing anon_vma
instead of forking new one.  It adds counter anon_vma->degree which
counts linked vmas and directly descending anon_vmas and reuses anon_vma
if counter is lower than two.  As a result each anon_vma has either vma
or at least two descending anon_vmas.  In such trees half of nodes are
leafs with alive vmas, thus count of anon_vmas is no more than two times
bigger than count of vmas.

This heuristic reuses anon_vmas as few as possible because each reuse
adds false aliasing among vmas and rmap walker ought to scan more ptes
when it searches where page is might be mapped.

Link: http://lkml.kernel.org/r/20120816024610.GA5350@evergreen.ssec.wisc.edu
Fixes: 5beb49305251 ("mm: change anon_vma linking to fix multi-process server scalability issue")
[akpm@linux-foundation.org: fix typo, per Rik]
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Reported-by: Daniel Forrest <dan.forrest@ssec.wisc.edu>
Tested-by: Michal Hocko <mhocko@suse.cz>
Tested-by: Jerome Marchand <jmarchan@redhat.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

Input: I8042 - add Acer Aspire 7738 to the nomux list

commit 9333caeaeae4f831054e0e127a6ed3948b604d3e upstream.

When KBC is in active multiplexing mode the touchpad on this laptop does
not work.

Reported-by: Bilal Koc <koc.bilo@googlemail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

regulator: core: fix race condition in regulator_put()

commit 83b0302d347a49f951e904184afe57ac3723476e upstream.

The regulator framework maintains a list of consumer regulators
for a regulator device and protects it from concurrent access using
the regulator device's mutex lock.

In the case of regulator_put() the consumer is removed and regulator
device's parameters are updated without holding the regulator device's
mutex. This would lead to a race condition between the regulator_put()
and any function which traverses the consumer list or modifies regulator
device's parameters.
Fix this race condition by holding the regulator device's mutex in case
of regulator_put.

Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
[bwh: Backported to 3.2:
- Adjust context
- Don't touch the comment; __regulator_put() has not been split out of
regulator_put() here]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

Input: i8042 - reset keyboard to fix Elantech touchpad detection

commit 148e9a711e034e06310a8c36b64957934ebe30f2 upstream.

On some laptops, keyboard needs to be reset in order to successfully detect
touchpad (e.g., some Gigabyte laptop models with Elantech touchpads).
Without resettin keyboard touchpad pretends to be completely dead.

Based on the original patch by Mateusz Jończyk this version has been
expanded to include DMI based detection & application of the fix
automatically on the affected models of laptops. This has been confirmed to
fix problem by three users already on three different models of laptops.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=81331
Signed-off-by: Srihari Vijayaraghavan <linux.bug.reporting@gmail.com>
Acked-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Tested-by: Srihari Vijayaraghavan <linux.bug.reporting@gmail.com>
Tested by: Zakariya Dehlawi <zdehlawi@gmail.com>
Tested-by: Guillaum Bouchard <guillaum.bouchard@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

time: settimeofday: Validate the values of tv from user

commit 6ada1fc0e1c4775de0e043e1bd3ae9d065491aa5 upstream.

An unvalidated user input is multiplied by a constant, which can result in
an undefined behaviour for large values. While this is validated later,
we should avoid triggering undefined behaviour.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
[jstultz: include trivial milisecond->microsecond correction noticed
by Andy]
Signed-off-by: John Stultz <john.stultz@linaro.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

sata_dwc_460ex: fix resource leak on error path

commit 4aaa71873ddb9faf4b0c4826579e2f6d18ff9ab4 upstream.

DMA mapped IO should be unmapped on the error path in probe() and
unconditionally on remove().

Fixes: 62936009f35a ([libata] Add 460EX on-chip SATA driver, sata_dwc_460ex)
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

mm: propagate error from stack expansion even for guard page

commit fee7e49d45149fba60156f5b59014f764d3e3728 upstream.

Jay Foad reports that the address sanitizer test (asan) sometimes gets
confused by a stack pointer that ends up being outside the stack vma
that is reported by /proc/maps.

This happens due to an interaction between RLIMIT_STACK and the guard
page: when we do the guard page check, we ignore the potential error
from the stack expansion, which effectively results in a missing guard
page, since the expected stack expansion won't have been done.

And since /proc/maps explicitly ignores the guard page (commit
d7824370e263: "mm: fix up some user-visible effects of the stack guard
page"), the stack pointer ends up being outside the reported stack area.

This is the minimal patch: it just propagates the error. It also
effectively makes the guard page part of the stack limit, which in turn
measn that the actual real stack is one page less than the stack limit.

Let's see if anybody notices. We could teach acct_stack_growth() to
allow an extra page for a grow-up/grow-down stack in the rlimit test,
but I don't want to add more complexity if it isn't needed.

Reported-and-tested-by: Jay Foad <jay.foad@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ASoC: wm8960: Fix capture sample rate from 11250 to 11025

commit 22ee76daddb87f88d2336d1b4737ef27c4f307ac upstream.

wm8960 codec can't support sample rate 11250, it must be 11025.

Signed-off-by: Zidan Wang <b50113@freescale.com>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

USB: cp210x: add IDs for CEL USB sticks and MeshWorks devices

commit 1ae78a4870989a354028cb17dabf819b595e70e3 upstream.

Added virtual com port VID/PID entries for CEL USB sticks and MeshWorks
devices.

Signed-off-by: David Peterson <david.peterson@cel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

virtio_pci: document why we defer kfree

commit a1eb03f546d651a8f39c7d0692b1f7f5b4e7e3cd upstream.

The reason we defer kfree until release function is because it's a
general rule for kobjects: kfree of the reference counter itself is only
legal in the release function.

Previous patch didn't make this clear, document this in code.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

virtio_pci: defer kfree until release callback

commit 63bd62a08ca45a0c804c3c89777edc7f76a2d6da upstream.

A struct device which has just been unregistered can live on past the
point at which a driver decides to drop it's initial reference to the
kobject gained on allocation.

This implies that when releasing a virtio device, we can't free a struct
virtio_device until the underlying struct device has been released,
which might not happen immediately on device_unregister().

Unfortunately, this is exactly what virtio pci does:
it has an empty release callback, and frees memory immediately
after unregistering the device.

This causes an easy to reproduce crash if CONFIG_DEBUG_KOBJECT_RELEASE
it enabled.

To fix, free the memory only once we know the device is gone in the release
callback.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

virtio: use dev_to_virtio wrapper in virtio

commit 9bffdca8c64a72ac54c47a552734ab457bc720d4 upstream.

Use dev_to_virtio wrapper in virtio to make code clearly.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

spi: dw-mid: fix FIFO size

commit 67bf9cda4b498b8cea4a40be67a470afe57d2e88 upstream.

The FIFO size is 40 accordingly to the specifications, but this means 0x40,
i.e. 64 bytes. This patch fixes the typo and enables FIFO size autodetection
for Intel MID devices.

Fixes: 7063c0d942a1 (spi/dw_spi: add DMA support)
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

spi: dw: Fix detecting FIFO depth

commit d297933cc7fcfbaaf2d37570baac73287bf0357d upstream.

Current code tries to find the highest valid fifo depth by checking the value
it wrote to DW_SPI_TXFLTR. There are a few problems in current code:
1) There is an off-by-one in dws->fifo_len setting because it assumes the latest
   register write fails so the latest valid value should be fifo - 1.
2) We know the depth could be from 2 to 256 from HW spec, so it is not necessary
   to test fifo == 257. In the case fifo is 257, it means the latest valid
   setting is fifo = 256. So after the for loop iteration, we should check
   fifo == 2 case instead of fifo == 257 if detecting the FIFO depth fails.
This patch fixes above issues.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Reviewed-and-tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ALSA: hda - Fix wrong gpio_dir & gpio_mask hint setups for IDT/STAC codecs

commit c507de88f6a336bd7296c9ec0073b2d4af8b4f5e upstream.

stac_store_hints() does utterly wrong for masking the values for
gpio_dir and gpio_data, likely due to copy&paste errors. Fortunately,
this feature is used very rarely, so the impact must be really small.

Reported-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

Revert "tcp: Apply device TSO segment limit earlier"

This reverts commit 9f871e883277cc22c6217db806376dce52401a31, which
was commit 1485348d2424e1131ea42efc033cbd9366462b01 upstream.

It can cause connections to stall when a PMTU event occurs. This was
fixed by commit 843925f33fcc ("tcp: Do not apply TSO segment limit to
non-TSO packets") upstream, but that depends on other changes to TSO.

The original issue this fixed was a performance regression for the sfc
driver in extreme cases of TSO (skb with > 100 segments). This is not
really very important and it seems best to revert it rather than try
to fix it up.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: netdev@vger.kernel.org
Cc: linux-net-drivers@solarflare.com

USB: cp210x: fix ID for production CEL MeshConnect USB Stick

commit 90441b4dbe90ba0c38111ea89fa093a8c9627801 upstream.

Fixing typo for MeshConnect IDs. The original PID (0x8875) is not in
production and is not needed. Instead it has been changed to the
official production PID (0x8857).

Signed-off-by: Preston Fick <pffick@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

video/fbdev: fix defio's fsync

commit 30ea9c5218651bc11cbdba7820be78f04e2d83bc upstream.

fb_deferred_io_fsync() returns the value of schedule_delayed_work() as
an error code, but schedule_delayed_work() does not return an error. It
returns true/false depending on whether the work was already queued.

Fix this by ignoring the return value of schedule_delayed_work().

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

video/logo: prevent use of logos after they have been freed

commit 92b004d1aa9f367c372511ca0330f58216b25703 upstream.

If the probe of an fb driver has been deferred due to missing
dependencies, and the probe is later ran when a module is loaded, the
fbdev framework will try to find a logo to use.

However, the logos are __initdata, and have already been freed. This
causes sometimes page faults, if the logo memory is not mapped,
sometimes other random crashes as the logo data is invalid, and
sometimes nothing, if the fbdev decides to reject the logo (e.g. the
random value depicting the logo's height is too big).

This patch adds a late_initcall function to mark the logos as freed. In
reality the logos are freed later, and fbdev probe may be ran between
this late_initcall and the freeing of the logos. In that case we will
miss drawing the logo, even if it would be possible.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

net: Fix stacked vlan offload features computation

commit 796f2da81bead71ffc91ef70912cd8d1827bf756 upstream.

When vlan tags are stacked, it is very likely that the outer tag is stored
in skb->vlan_tci and skb->protocol shows the inner tag's vlan_proto.
Currently netif_skb_features() first looks at skb->protocol even if there
is the outer tag in vlan_tci, thus it incorrectly retrieves the protocol
encapsulated by the inner vlan instead of the inner vlan protocol.
This allows GSO packets to be passed to HW and they end up being
corrupted.

Fixes: 58e998c6d239 ("offloading: Force software GSO for multiple vlan tags.")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2:
- We don't support 802.1ad tag offload
- Keep passing protocol to harmonize_features()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

crypto: af_alg - fix backlog handling

commit 7e77bdebff5cb1e9876c561f69710b9ab8fa1f7e upstream.

If a request is backlogged, it's complete() handler will get called
twice: once with -EINPROGRESS, and once with the final error code.

af_alg's complete handler, unlike other users, does not handle the
-EINPROGRESS but instead always completes the completion that recvmsg()
is waiting on.  This can lead to a return to user space while the
request is still pending in the driver.  If userspace closes the sockets
before the requests are handled by the driver, this will lead to
use-after-frees (and potential crashes) in the kernel due to the tfm
having been freed.

The crashes can be easily reproduced (for example) by reducing the max
queue length in cryptod.c and running the following (from
http://www.chronox.de/libkcapi.html) on AES-NI capable hardware:

$ while true; do kcapi -x 1 -e -c '__ecb-aes-aesni' \
    -k 00000000000000000000000000000000 \
    -p 00000000000000000000000000000000 >/dev/null & done

Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

udf: Check component length before reading it

commit e237ec37ec154564f8690c5bd1795339955eeef9 upstream.

Check that length specified in a component of a symlink fits in the
input buffer we are reading. Also properly ignore component length for
component types that do not use it. Otherwise we read memory after end
of buffer for corrupted udf image.

Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

x86_64, vdso: Fix the vdso address randomization algorithm

commit 394f56fe480140877304d342dec46d50dc823d46 upstream.

The theory behind vdso randomization is that it's mapped at a random
offset above the top of the stack.  To avoid wasting a page of
memory for an extra page table, the vdso isn't supposed to extend
past the lowest PMD into which it can fit.  Other than that, the
address should be a uniformly distributed address that meets all of
the alignment requirements.

The current algorithm is buggy: the vdso has about a 50% probability
of being at the very end of a PMD.  The current algorithm also has a
decent chance of failing outright due to incorrect handling of the
case where the top of the stack is near the top of its PMD.

This fixes the implementation.  The paxtest estimate of vdso
"randomisation" improves from 11 bits to 18 bits.  (Disclaimer: I
don't know what the paxtest code is actually calculating.)

It's worth noting that this algorithm is inherently biased: the vdso
is more likely to end up near the end of its PMD than near the
beginning.  Ideally we would either nix the PMD sharing requirement
or jointly randomize the vdso and the stack to reduce the bias.

In the mean time, this is a considerable improvement with basically
no risk of compatibility issues, since the allowed outputs of the
algorithm are unchanged.

As an easy test, doing this:

for i in `seq 10000`
  do grep -P vdso /proc/self/maps |cut -d- -f1
done |sort |uniq -d

used to produce lots of output (1445 lines on my most recent run).
A tiny subset looks like this:

7fffdfffe000
7fffe01fe000
7fffe05fe000
7fffe07fe000
7fffe09fe000
7fffe0bfe000
7fffe0dfe000

Note the suspicious fe000 endings.  With the fix, I get a much more
palatable 76 repeated addresses.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
[bwh: Backported to 3.2:
- Adjust context
- The whole file is only built for x86_64; adjust comment for this]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

udf: Check path length when reading symlink

commit 0e5cc9a40ada6046e6bc3bdfcd0c0d7e4b706b14 upstream.

Symlink reading code does not check whether the resulting path fits into
the page provided by the generic code. This isn't as easy as just
checking the symlink size because of various encoding conversions we
perform on path. So we have to check whether there is still enough space
in the buffer on the fly.

Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: Jan Kara <jack@suse.cz>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

udf: Treat symlink component of type 2 as /

commit fef2e9f3301934773e4f1b3cc5c7bffb119346b8 upstream.

Currently, we ignore symlink component of type 2. But mkisofs and other OS'
seem to treat it as / so do the same for compatibility.

Reported-by: "Gábor S." <otnaccess@hotmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

udf: Verify symlink size before loading it

commit a1d47b262952a45aae62bd49cfaf33dd76c11a2c upstream.

UDF specification allows arbitrarily large symlinks. However we support
only symlinks at most one block large. Check the length of the symlink
so that we don't access memory beyond end of the symlink block.

Reported-by: Carl Henrik Lunde <chlunde@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

udf: Verify i_size when loading inode

commit e159332b9af4b04d882dbcfe1bb0117f0a6d4b58 upstream.

Verify that inode size is sane when loading inode with data stored in
ICB. Otherwise we may get confused later when working with the inode and
inode size is too big.

Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: Jan Kara <jack@suse.cz>
[bwh: Backported to 3.2: on error, call make_bad_inode() then return]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

isofs: Fix unchecked printing of ER records

commit 4e2024624e678f0ebb916e6192bd23c1f9fdf696 upstream.

We didn't check length of rock ridge ER records before printing them.
Thus corrupted isofs image can cause us to access and print some memory
behind the buffer with obvious consequences.

Reported-and-tested-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ocfs2: fix journal commit deadlock

commit 136f49b9171074872f2a14ad0ab10486d1ba13ca upstream.

For buffer write, page lock will be got in write_begin and released in
write_end, in ocfs2_write_end_nolock(), before it unlock the page in
ocfs2_free_write_ctxt(), it calls ocfs2_run_deallocs(), this will ask
for the read lock of journal->j_trans_barrier. Holding page lock and
ask for journal->j_trans_barrier breaks the locking order.

This will cause a deadlock with journal commit threads, ocfs2cmt will
get write lock of journal->j_trans_barrier first, then it wakes up
kjournald2 to do the commit work, at last it waits until done. To
commit journal, kjournald2 needs flushing data first, it needs get the
cache page lock.

Since some ocfs2 cluster locks are holding by write process, this
deadlock may hung the whole cluster.

unlock pages before ocfs2_run_deallocs() can fix the locking order, also
put unlock before ocfs2_commit_trans() to make page lock is unlocked
before j_trans_barrier to preserve unlocking order.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ALSA: usb-audio: extend KEF X300A FU 10 tweak to Arcam rPAC

commit d70a1b9893f820fdbcdffac408c909c50f2e6b43 upstream.

The Arcam rPAC seems to have the same problem - whenever anything
(alsamixer, udevd, 3.9+ kernel from 60af3d037eb8c, ..) attempts to
access mixer / control interface of the card, the firmware "locks up"
the entire device, resulting in
SNDRV_PCM_IOCTL_HW_PARAMS failed (-5): Input/output error
from alsa-lib.

Other operating systems can somehow read the mixer (there seems to be
playback volume/mute), but any manipulation is ignored by the device
(which has hardware volume controls).

Signed-off-by: Jiri Jaburek <jjaburek@redhat.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

x86/tls: Don't validate lm in set_thread_area() after all

commit 3fb2f4237bb452eb4e98f6a5dbd5a445b4fed9d0 upstream.

It turns out that there's a lurking ABI issue.  GCC, when
compiling this in a 32-bit program:

struct user_desc desc = {
.entry_number    = idx,
.base_addr       = base,
.limit           = 0xfffff,
.seg_32bit       = 1,
.contents        = 0, /* Data, grow-up */
.read_exec_only  = 0,
.limit_in_pages  = 1,
.seg_not_present = 0,
.useable         = 0,
};

will leave .lm uninitialized.  This means that anything in the
kernel that reads user_desc.lm for 32-bit tasks is unreliable.

Revert the .lm check in set_thread_area().  The value never did
anything in the first place.

Fixes: 0e58af4e1d21 ("x86/tls: Disallow unusual TLS segments")
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/d7875b60e28c512f6a6fc0baf5714d58e7eaadbb.1418856405.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

ceph: introduce global empty snap context

commit 97c85a828f36bbfffe9d77b977b65a5872b6cad4 upstream.

Current snaphost code does not properly handle moving inode from one
empty snap realm to another empty snap realm. After changing inode's
snap realm, some dirty pages' snap context can be not equal to inode's
i_head_snap. This can trigger BUG() in ceph_put_wrbuffer_cap_refs()

The fix is introduce a global empty snap context for all empty snap
realm. This avoids triggering the BUG() for filesystem with no snapshot.

Fixes: http://tracker.ceph.com/issues/9928

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
[bwh: Backported to 3.2:
- Adjust context
- As we don't have ceph_create_snap_context(), open-code it in
ceph_snap_init()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

iscsi-target: Fail connection on short sendmsg writes

commit 6bf6ca7515c1df06f5c03737537f5e0eb191e29e upstream.

This patch changes iscsit_do_tx_data() to fail on short writes
when kernel_sendmsg() returns a value different than requested
transfer length, returning -EPIPE and thus causing a connection
reset to occur.

This avoids a potential bug in the original code where a short
write would result in kernel_sendmsg() being called again with
the original iovec base + length.

In practice this has not been an issue because iscsit_do_tx_data()
is only used for transferring 48 byte headers + 4 byte digests,
along with seldom used control payloads from NOPIN + TEXT_RSP +
REJECT with less than 32k of data.

So following Al's audit of iovec consumers, go ahead and fail
the connection on short writes for now, and remove the bogus
logic ahead of his proper upstream fix.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

isofs: Fix infinite looping over CE entries

commit f54e18f1b831c92f6512d2eedb224cd63d607d3d upstream.

Rock Ridge extensions define so called Continuation Entries (CE) which
define where is further space with Rock Ridge data. Corrupted isofs
image can contain arbitrarily long chain of these, including a one
containing loop and thus causing kernel to end in an infinite loop when
traversing these entries.

Limit the traversal to 32 entries which should be more than enough space
to store all the Rock Ridge data.

Reported-by: P J P <ppandit@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

x86/tls: Disallow unusual TLS segments

commit 0e58af4e1d2166e9e33375a0f121e4867010d4f8 upstream.

Users have no business installing custom code segments into the
GDT, and segments that are not present but are otherwise valid
are a historical source of interesting attacks.

For completeness, block attempts to set the L bit.  (Prior to
this patch, the L bit would have been silently dropped.)

This is an ABI break.  I've checked glibc, musl, and Wine, and
none of them look like they'll have any trouble.

Note to stable maintainers: this is a hardening patch that fixes
no known bugs.  Given the possibility of ABI issues, this
probably shouldn't be backported quickly.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: security@kernel.org <security@kernel.org>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>