linux-stable.git/include/linux, branch v3.18.26

USB: add quirk for devices with broken LPM

2016-01-22T17:24:44+00:00

[ Upstream commit ad87e03213b552a5c33d5e1e7a19a73768397010 ]

Some USB device / host controller combinations seem to have problems
with Link Power Management.  For example, Steinar found that his xHCI
controller wouldn't handle bandwidth calculations correctly for two
video cards simultaneously when LPM was enabled, even though the bus
had plenty of bandwidth available.

This patch introduces a new quirk flag for devices that should remain
disabled for LPM, and creates quirk entries for Steinar's devices.

Signed-off-by: Alan Stern 
Reported-by: Steinar H. Gunderson 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

ext4, jbd2: ensure entering into panic after recording an error in superblock

2016-01-21T16:23:28+00:00

[ Upstream commit 4327ba52afd03fc4b5afa0ee1d774c9c5b0e85c5 ]

If a EXT4 filesystem utilizes JBD2 journaling and an error occurs, the
journaling will be aborted first and the error number will be recorded
into JBD2 superblock and, finally, the system will enter into the
panic state in "errors=panic" option.  But, in the rare case, this
sequence is little twisted like the below figure and it will happen
that the system enters into panic state, which means the system reset
in mobile environment, before completion of recording an error in the
journal superblock. In this case, e2fsck cannot recognize that the
filesystem failure occurred in the previous run and the corruption
wouldn't be fixed.

Task A                        Task B
ext4_handle_error()
-> jbd2_journal_abort()
  -> __journal_abort_soft()
    -> __jbd2_journal_abort_hard()
    | -> journal->j_flags |= JBD2_ABORT;
    |
    |                         __ext4_abort()
    |                         -> jbd2_journal_abort()
    |                         | -> __journal_abort_soft()
    |                         |   -> if (journal->j_flags & JBD2_ABORT)
    |                         |           return;
    |                         -> panic()
    |
    -> jbd2_journal_update_sb_errno()

Tested-by: Hobin Woo 
Signed-off-by: Daeho Jeong 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin

ipv6: add complete rcu protection around np->opt

2015-12-14T17:19:26+00:00

[ Upstream commit 45f6fad84cc305103b28d73482b344d7f5b76f39 ]

This patch addresses multiple problems :

UDP/RAW sendmsg() need to get a stable struct ipv6_txoptions
while socket is not locked : Other threads can change np->opt
concurrently. Dmitry posted a syzkaller
(http://github.com/google/syzkaller) program desmonstrating
use-after-free.

Starting with TCP/DCCP lockless listeners, tcp_v6_syn_recv_sock()
and dccp_v6_request_recv_sock() also need to use RCU protection
to dereference np->opt once (before calling ipv6_dup_options())

This patch adds full RCU protection to np->opt

Reported-by: Dmitry Vyukov 
Signed-off-by: Eric Dumazet 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

PCI: Add dev_flags bit to access VPD through function 0

2015-12-03T03:35:38+00:00

[ Upstream commit 91a37c794cf2cf7ec1f9afc4cbf4a118df7e085e ]

commit 932c435caba8a2ce473a91753bad0173269ef334 upstream.

Add a dev_flags bit, PCI_DEV_FLAGS_VPD_REF_F0, to access VPD through
function 0 to provide VPD access on other functions.  This is for hardware
devices that provide copies of the same VPD capability registers in
multiple functions.  Because the kernel expects that each function has its
own registers, both the locking and the state tracking are affected by VPD
accesses to different functions.

On such devices for example, if a VPD write is performed on function 0,
*any* later attempt to read VPD from any other function of that device will
hang.  This has to do with how the kernel tracks the expected value of the
F bit per function.

Concurrent accesses to different functions of the same device can not only
hang but also corrupt both read and write VPD data.

When hangs occur, typically the error message:

  vpd r/w failed.  This is likely a firmware bug on this device.

will be seen.

Never set this bit on function 0 or there will be an infinite recursion.

Signed-off-by: Mark Rustad 
Signed-off-by: Bjorn Helgaas 
Acked-by: Alexander Duyck 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

PCI: Add flag for devices that don't reset on D3hot->D0 transition

2015-12-03T03:35:32+00:00

[ Upstream commit 51e537387990dc1f00752103f314fd135cb94bc6 ]

Per the PCI Power Management spec r1.2, sec 3.2.4, a device that advertises
No_Soft_Reset == 0 in the PMCSR register (reported by lspci as "NoSoftRst-")
should perform an internal reset when transitioning from D3hot to D0 via
software control.  Configuration context is lost and the device requires a
full reinitialization sequence.

Unfortunately the definition of "internal reset", beyond the application of
the configuration context, is largely left to the interpretation of the
specific device.  Some devices don't seem to perform an "internal reset"
even if they report No_Soft_Reset == 0.

We still need to honor the PCI specification and restore PCI config context
in the event that we do a PM reset, so we don't cache and modify the
PCI_PM_CTRL_NO_SOFT_RESET bit for the device, but for interfaces where the
intention is to reset the device, like pci_reset_function(), we need a
mechanism to flag that PM reset (a D3hot->D0 transition) doesn't perform
any significant "internal reset" of the device.

Signed-off-by: Alex Williamson 
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Sasha Levin

skbuff: Fix skb checksum partial check.

2015-11-13T18:16:36+00:00

[ Upstream commit 31b33dfb0a144469dd805514c9e63f4993729a48 ]

Earlier patch 6ae459bda tried to detect void ckecksum partial
skb by comparing pull length to checksum offset. But it does
not work for all cases since checksum-offset depends on
updates to skb->data.

Following patch fixes it by validating checksum start offset
after skb-data pointer is updated. Negative value of checksum
offset start means there is no need to checksum.

Fixes: 6ae459bda ("skbuff: Fix skb checksum flag on skb pull")
Reported-by: Andrew Vagin 
Signed-off-by: Pravin B Shelar 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

skbuff: Fix skb checksum flag on skb pull

2015-11-13T18:16:24+00:00

[ Upstream commit 6ae459bdaaeebc632b16e54dcbabb490c6931d61 ]

VXLAN device can receive skb with checksum partial. But the checksum
offset could be in outer header which is pulled on receive. This results
in negative checksum offset for the skb. Such skb can cause the assert
failure in skb_checksum_help(). Following patch fixes the bug by setting
checksum-none while pulling outer header.

Following is the kernel panic msg from old kernel hitting the bug.

------------[ cut here ]------------
kernel BUG at net/core/dev.c:1906!
RIP: 0010:[] skb_checksum_help+0x144/0x150
Call Trace:

[] queue_userspace_packet+0x408/0x470 [openvswitch]
[] ovs_dp_upcall+0x5d/0x60 [openvswitch]
[] ovs_dp_process_packet_with_key+0xe6/0x100 [openvswitch]
[] ovs_dp_process_received_packet+0x4b/0x80 [openvswitch]
[] ovs_vport_receive+0x2a/0x30 [openvswitch]
[] vxlan_rcv+0x53/0x60 [openvswitch]
[] vxlan_udp_encap_recv+0x8b/0xf0 [openvswitch]
[] udp_queue_rcv_skb+0x2dc/0x3b0
[] __udp4_lib_rcv+0x1cf/0x6c0
[] udp_rcv+0x1a/0x20
[] ip_local_deliver_finish+0xdd/0x280
[] ip_local_deliver+0x88/0x90
[] ip_rcv_finish+0x10d/0x370
[] ip_rcv+0x235/0x300
[] __netif_receive_skb+0x55d/0x620
[] netif_receive_skb+0x80/0x90
[] virtnet_poll+0x555/0x6f0
[] net_rx_action+0x134/0x290
[] __do_softirq+0xa8/0x210
[] call_softirq+0x1c/0x30
[] do_softirq+0x65/0xa0
[] irq_exit+0x8e/0xb0
[] do_IRQ+0x63/0xe0
[] common_interrupt+0x6e/0x6e

Reported-by: Anupam Chanda 
Signed-off-by: Pravin B Shelar 
Acked-by: Tom Herbert 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

jbd2: avoid infinite loop when destroying aborted journal

2015-11-13T18:14:15+00:00

[ Upstream commit 841df7df196237ea63233f0f9eaa41db53afd70f ]

Commit 6f6a6fda2945 "jbd2: fix ocfs2 corrupt when updating journal
superblock fails" changed jbd2_cleanup_journal_tail() to return EIO
when the journal is aborted. That makes logic in
jbd2_log_do_checkpoint() bail out which is fine, except that
jbd2_journal_destroy() expects jbd2_log_do_checkpoint() to always make
a progress in cleaning the journal. Without it jbd2_journal_destroy()
just loops in an infinite loop.

Fix jbd2_journal_destroy() to cleanup journal checkpoint lists of
jbd2_log_do_checkpoint() fails with error.

Reported-by: Eryu Guan 
Tested-by: Eryu Guan 
Fixes: 6f6a6fda294506dfe0e3e0a253bb2d2923f28f0a
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

iio: Add inverse unit conversion macros

2015-10-28T02:14:36+00:00

[ Upstream commit c689a923c867eac40ed3826c1d9328edea8b6bc7 ]

Add inverse unit conversion macro to convert from standard IIO units to
units that might be used by some devices.

Those are useful in combination with scale factors that are specified as
IIO_VAL_FRACTIONAL. Typically the denominator for those specifications will
contain the maximum raw value the sensor will generate and the numerator
the value it maps to in a specific unit. Sometimes datasheets specify those
in different units than the standard IIO units (e.g. degree/s instead of
rad/s) and so we need to do a unit conversion.

From a mathematical point of view it does not make a difference whether we
apply the unit conversion to the numerator or the inverse unit conversion
to the denominator since (x / y) / z = x / (y * z). But as the denominator
is typically a larger value and we are rounding both the numerator and
denominator to integer values using the later method gives us a better
precision (E.g. the relative error is smaller if we round 8000.3 to 8000
rather than rounding 8.3 to 8).

This is where in inverse unit conversion macros will be used.

Marked for stable as used by some upcoming fixes.

Signed-off-by: Lars-Peter Clausen 
Cc: 
Signed-off-by: Jonathan Cameron 
Signed-off-by: Sasha Levin

overlayfs: Make f_path always point to the overlay and f_inode to the underlay

2015-10-28T02:14:24+00:00

[ Upstream commit 4bacc9c9234c7c8eec44f5ed4e960d9f96fa0f01 ]

Make file->f_path always point to the overlay dentry so that the path in
/proc/pid/fd is correct and to ensure that label-based LSMs have access to the
overlay as well as the underlay (path-based LSMs probably don't need it).

Using my union testsuite to set things up, before the patch I see:

	[root@andromeda union-testsuite]# bash 5 /a/foo107
	[root@andromeda union-testsuite]# stat /mnt/a/foo107
	...
	Device: 23h/35d Inode: 13381       Links: 1
	...
	[root@andromeda union-testsuite]# stat -L /proc/$$/fd/5
	...
	Device: 23h/35d Inode: 13381       Links: 1
	...

After the patch:

	[root@andromeda union-testsuite]# bash 5 /mnt/a/foo107
	[root@andromeda union-testsuite]# stat /mnt/a/foo107
	...
	Device: 23h/35d Inode: 40346       Links: 1
	...
	[root@andromeda union-testsuite]# stat -L /proc/$$/fd/5
	...
	Device: 23h/35d Inode: 40346       Links: 1
	...

Note the change in where /proc/$$/fd/5 points to in the ls command.  It was
pointing to /a/foo107 (which doesn't exist) and now points to /mnt/a/foo107
(which is correct).

The inode accessed, however, is the lower layer.  The union layer is on device
25h/37d and the upper layer on 24h/36d.

Signed-off-by: David Howells 
Signed-off-by: Al Viro 
Signed-off-by: Sasha Levin