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linux-stable
8 years agoLinux 4.1.19 v4.1.19
Sasha Levin [Fri, 4 Mar 2016 21:55:54 +0000 (16:55 -0500)]
Linux 4.1.19

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agosctp: Fix port hash table size computation
Neil Horman [Thu, 18 Feb 2016 21:10:57 +0000 (16:10 -0500)]
sctp: Fix port hash table size computation

[ Upstream commit d9749fb5942f51555dc9ce1ac0dbb1806960a975 ]

Dmitry Vyukov noted recently that the sctp_port_hashtable had an error in
its size computation, observing that the current method never guaranteed
that the hashsize (measured in number of entries) would be a power of two,
which the input hash function for that table requires.  The root cause of
the problem is that two values need to be computed (one, the allocation
order of the storage requries, as passed to __get_free_pages, and two the
number of entries for the hash table).  Both need to be ^2, but for
different reasons, and the existing code is simply computing one order
value, and using it as the basis for both, which is wrong (i.e. it assumes
that ((1<<order)*PAGE_SIZE)/sizeof(bucket) is still ^2 when its not).

To fix this, we change the logic slightly.  We start by computing a goal
allocation order (which is limited by the maximum size hash table we want
to support.  Then we attempt to allocate that size table, decreasing the
order until a successful allocation is made.  Then, with the resultant
successful order we compute the number of buckets that hash table supports,
which we then round down to the nearest power of two, giving us the number
of entries the table actually supports.

I've tested this locally here, using non-debug and spinlock-debug kernels,
and the number of entries in the hashtable consistently work out to be
powers of two in all cases.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
CC: Dmitry Vyukov <dvyukov@google.com>
CC: Vladislav Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agounix_diag: fix incorrect sign extension in unix_lookup_by_ino
Dmitry V. Levin [Fri, 19 Feb 2016 01:27:48 +0000 (04:27 +0300)]
unix_diag: fix incorrect sign extension in unix_lookup_by_ino

[ Upstream commit b5f0549231ffb025337be5a625b0ff9f52b016f0 ]

The value passed by unix_diag_get_exact to unix_lookup_by_ino has type
__u32, but unix_lookup_by_ino's argument ino has type int, which is not
a problem yet.
However, when ino is compared with sock_i_ino return value of type
unsigned long, ino is sign extended to signed long, and this results
to incorrect comparison on 64-bit architectures for inode numbers
greater than INT_MAX.

This bug was found by strace test suite.

Fixes: 5d3cae8bc39d ("unix_diag: Dumping exact socket core")
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agortnl: RTM_GETNETCONF: fix wrong return value
Anton Protopopov [Wed, 17 Feb 2016 02:43:16 +0000 (21:43 -0500)]
rtnl: RTM_GETNETCONF: fix wrong return value

[ Upstream commit a97eb33ff225f34a8124774b3373fd244f0e83ce ]

An error response from a RTM_GETNETCONF request can return the positive
error value EINVAL in the struct nlmsgerr that can mislead userspace.

Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoroute: check and remove route cache when we get route
Xin Long [Thu, 18 Feb 2016 13:21:19 +0000 (21:21 +0800)]
route: check and remove route cache when we get route

[ Upstream commit deed49df7390d5239024199e249190328f1651e7 ]

Since the gc of ipv4 route was removed, the route cached would has
no chance to be removed, and even it has been timeout, it still could
be used, cause no code to check it's expires.

Fix this issue by checking  and removing route cache when we get route.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agopppoe: fix reference counting in PPPoE proxy
Guillaume Nault [Mon, 15 Feb 2016 16:01:10 +0000 (17:01 +0100)]
pppoe: fix reference counting in PPPoE proxy

[ Upstream commit 29e73269aa4d36f92b35610c25f8b01c789b0dc8 ]

Drop reference on the relay_po socket when __pppoe_xmit() succeeds.
This is already handled correctly in the error path.

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agol2tp: Fix error creating L2TP tunnels
Mark Tomlinson [Mon, 15 Feb 2016 03:24:44 +0000 (16:24 +1300)]
l2tp: Fix error creating L2TP tunnels

[ Upstream commit 853effc55b0f975abd6d318cca486a9c1b67e10f ]

A previous commit (33f72e6) added notification via netlink for tunnels
when created/modified/deleted. If the notification returned an error,
this error was returned from the tunnel function. If there were no
listeners, the error code ESRCH was returned, even though having no
listeners is not an error. Other calls to this and other similar
notification functions either ignore the error code, or filter ESRCH.
This patch checks for ESRCH and does not flag this as an error.

Reviewed-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agonet/mlx4_en: Avoid changing dev->features directly in run-time
Eugenia Emantayev [Wed, 17 Feb 2016 15:24:27 +0000 (17:24 +0200)]
net/mlx4_en: Avoid changing dev->features directly in run-time

[ Upstream commit 925ab1aa9394bbaeac47ee5b65d3fdf0fb8135cf ]

It's forbidden to manually change dev->features in run-time. Currently, this is
done in the driver to make sure that GSO_UDP_TUNNEL is advertized only when
VXLAN tunnel is set. However, since the stack actually does features intersection
with hw_enc_features, we can safely revert to advertizing features early when
registering the netdevice.

Fixes: f4a1edd56120 ('net/mlx4_en: Advertize encapsulation offloads [...]')
Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agonet/mlx4_en: Choose time-stamping shift value according to HW frequency
Eugenia Emantayev [Wed, 17 Feb 2016 15:24:23 +0000 (17:24 +0200)]
net/mlx4_en: Choose time-stamping shift value according to HW frequency

[ Upstream commit 31c128b66e5b28f468076e4f3ca3025c35342041 ]

Previously, the shift value used for time-stamping was constant and didn't
depend on the HW chip frequency. Change that to take the frequency into account
and calculate the maximal value in cycles per wraparound of ten seconds. This
time slot was chosen since it gives a good accuracy in time synchronization.

Algorithm for shift value calculation:
 * Round up the maximal value in cycles to nearest power of two

 * Calculate maximal multiplier by division of all 64 bits set
   to above result

 * Then, invert the function clocksource_khz2mult() to get the shift from
   maximal mult value

Fixes: ec693d47010e ('net/mlx4_en: Add HW timestamping (TS) support')
Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Reviewed-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agonet/mlx4_en: Count HW buffer overrun only once
Amir Vadai [Wed, 17 Feb 2016 15:24:22 +0000 (17:24 +0200)]
net/mlx4_en: Count HW buffer overrun only once

[ Upstream commit 281e8b2fdf8e4ef366b899453cae50e09b577ada ]

RdropOvflw counts overrun of HW buffer, therefore should
be used for rx_fifo_errors only.

Currently RdropOvflw counter is mistakenly also set into
rx_missed_errors and rx_over_errors too, which makes the
device total dropped packets accounting to show wrong results.

Fix that. Use it for rx_fifo_errors only.

Fixes: c27a02cd94d6 ('mlx4_en: Add driver for Mellanox ConnectX 10GbE NIC')
Signed-off-by: Amir Vadai <amir@vadai.me>
Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoqmi_wwan: add "4G LTE usb-modem U901"
Bjørn Mork [Fri, 12 Feb 2016 15:42:14 +0000 (16:42 +0100)]
qmi_wwan: add "4G LTE usb-modem U901"

[ Upstream commit aac8d3c282e024c344c5b86dc1eab7af88bb9716 ]

Thomas reports:

T:  Bus=01 Lev=01 Prnt=01 Port=03 Cnt=01 Dev#=  4 Spd=480 MxCh= 0
D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=05c6 ProdID=6001 Rev=00.00
S:  Manufacturer=USB Modem
S:  Product=USB Modem
S:  SerialNumber=1234567890ABCDEF
C:  #Ifs= 5 Cfg#= 1 Atr=e0 MxPwr=500mA
I:  If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
I:  If#= 1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
I:  If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
I:  If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan
I:  If#= 4 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage

Reported-by: Thomas Schäfer <tschaefer@t-online.de>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoaf_unix: Guard against other == sk in unix_dgram_sendmsg
Rainer Weikusat [Thu, 11 Feb 2016 19:37:27 +0000 (19:37 +0000)]
af_unix: Guard against other == sk in unix_dgram_sendmsg

[ Upstream commit a5527dda344fff0514b7989ef7a755729769daa1 ]

The unix_dgram_sendmsg routine use the following test

if (unlikely(unix_peer(other) != sk && unix_recvq_full(other))) {

to determine if sk and other are in an n:1 association (either
established via connect or by using sendto to send messages to an
unrelated socket identified by address). This isn't correct as the
specified address could have been bound to the sending socket itself or
because this socket could have been connected to itself by the time of
the unix_peer_get but disconnected before the unix_state_lock(other). In
both cases, the if-block would be entered despite other == sk which
might either block the sender unintentionally or lead to trying to unlock
the same spin lock twice for a non-blocking send. Add a other != sk
check to guard against this.

Fixes: 7d267278a9ec ("unix: avoid use-after-free in ep_remove_wait_queue")
Reported-By: Philipp Hahn <pmhahn@pmhahn.de>
Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Tested-by: Philipp Hahn <pmhahn@pmhahn.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoipv4: fix memory leaks in ip_cmsg_send() callers
Eric Dumazet [Thu, 4 Feb 2016 14:23:28 +0000 (06:23 -0800)]
ipv4: fix memory leaks in ip_cmsg_send() callers

[ Upstream commit 919483096bfe75dda338e98d56da91a263746a0a ]

Dmitry reported memory leaks of IP options allocated in
ip_cmsg_send() when/if this function returns an error.

Callers are responsible for the freeing.

Many thanks to Dmitry for the report and diagnostic.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agobonding: Fix ARP monitor validation
Jay Vosburgh [Tue, 2 Feb 2016 21:35:56 +0000 (13:35 -0800)]
bonding: Fix ARP monitor validation

[ Upstream commit 21a75f0915dde8674708b39abfcda113911c49b1 ]

The current logic in bond_arp_rcv will accept an incoming ARP for
validation if (a) the receiving slave is either "active" (which includes
the currently active slave, or the current ARP slave) or, (b) there is a
currently active slave, and it has received an ARP since it became active.
For case (b), the receiving slave isn't the currently active slave, and is
receiving the original broadcast ARP request, not an ARP reply from the
target.

This logic can fail if there is no currently active slave.  In
this situation, the ARP probe logic cycles through all slaves, assigning
each in turn as the "current_arp_slave" for one arp_interval, then setting
that one as "active," and sending an ARP probe from that slave.  The
current logic expects the ARP reply to arrive on the sending
current_arp_slave, however, due to switch FDB updating delays, the reply
may be directed to another slave.

This can arise if the bonding slaves and switch are working, but
the ARP target is not responding.  When the ARP target recovers, a
condition may result wherein the ARP target host replies faster than the
switch can update its forwarding table, causing each ARP reply to be sent
to the previous current_arp_slave.  This will never pass the logic in
bond_arp_rcv, as neither of the above conditions (a) or (b) are met.

Some experimentation on a LAN shows ARP reply round trips in the
200 usec range, but my available switches never update their FDB in less
than 4000 usec.

This patch changes the logic in bond_arp_rcv to additionally
accept an ARP reply for validation on any slave if there is a current ARP
slave and it sent an ARP probe during the previous arp_interval.

Fixes: aeea64ac717a ("bonding: don't trust arp requests unless active slave really works")
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agobpf: fix branch offset adjustment on backjumps after patching ctx expansion
Daniel Borkmann [Wed, 10 Feb 2016 15:47:11 +0000 (16:47 +0100)]
bpf: fix branch offset adjustment on backjumps after patching ctx expansion

[ Upstream commit a1b14d27ed0965838350f1377ff97c93ee383492 ]

When ctx access is used, the kernel often needs to expand/rewrite
instructions, so after that patching, branch offsets have to be
adjusted for both forward and backward jumps in the new eBPF program,
but for backward jumps it fails to account the delta. Meaning, for
example, if the expansion happens exactly on the insn that sits at
the jump target, it doesn't fix up the back jump offset.

Analysis on what the check in adjust_branches() is currently doing:

  /* adjust offset of jmps if necessary */
  if (i < pos && i + insn->off + 1 > pos)
    insn->off += delta;
  else if (i > pos && i + insn->off + 1 < pos)
    insn->off -= delta;

First condition (forward jumps):

  Before:                         After:

  insns[0]                        insns[0]
  insns[1] <--- i/insn            insns[1] <--- i/insn
  insns[2] <--- pos               insns[P] <--- pos
  insns[3]                        insns[P]  `------| delta
  insns[4] <--- target_X          insns[P]   `-----|
  insns[5]                        insns[3]
                                  insns[4] <--- target_X
                                  insns[5]

First case is if we cross pos-boundary and the jump instruction was
before pos. This is handeled correctly. I.e. if i == pos, then this
would mean our jump that we currently check was the patchlet itself
that we just injected. Since such patchlets are self-contained and
have no awareness of any insns before or after the patched one, the
delta is correctly not adjusted. Also, for the second condition in
case of i + insn->off + 1 == pos, means we jump to that newly patched
instruction, so no offset adjustment are needed. That part is correct.

Second condition (backward jumps):

  Before:                         After:

  insns[0]                        insns[0]
  insns[1] <--- target_X          insns[1] <--- target_X
  insns[2] <--- pos <-- target_Y  insns[P] <--- pos <-- target_Y
  insns[3]                        insns[P]  `------| delta
  insns[4] <--- i/insn            insns[P]   `-----|
  insns[5]                        insns[3]
                                  insns[4] <--- i/insn
                                  insns[5]

Second interesting case is where we cross pos-boundary and the jump
instruction was after pos. Backward jump with i == pos would be
impossible and pose a bug somewhere in the patchlet, so the first
condition checking i > pos is okay only by itself. However, i +
insn->off + 1 < pos does not always work as intended to trigger the
adjustment. It works when jump targets would be far off where the
delta wouldn't matter. But, for example, where the fixed insn->off
before pointed to pos (target_Y), it now points to pos + delta, so
that additional room needs to be taken into account for the check.
This means that i) both tests here need to be adjusted into pos + delta,
and ii) for the second condition, the test needs to be <= as pos
itself can be a target in the backjump, too.

Fixes: 9bac3d6d548e ("bpf: allow extended BPF programs access skb fields")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agonet: Copy inner L3 and L4 headers as unaligned on GRE TEB
Alexander Duyck [Tue, 9 Feb 2016 14:14:43 +0000 (06:14 -0800)]
net: Copy inner L3 and L4 headers as unaligned on GRE TEB

[ Upstream commit 78565208d73ca9b654fb9a6b142214d52eeedfd1 ]

This patch corrects the unaligned accesses seen on GRE TEB tunnels when
generating hash keys.  Specifically what this patch does is make it so that
we force the use of skb_copy_bits when the GRE inner headers will be
unaligned due to NET_IP_ALIGNED being a non-zero value.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoflow_dissector: Fix unaligned access in __skb_flow_dissector when used by eth_get_headlen
Alexander Duyck [Tue, 9 Feb 2016 10:49:54 +0000 (02:49 -0800)]
flow_dissector: Fix unaligned access in __skb_flow_dissector when used by eth_get_headlen

[ Upstream commit 461547f3158978c180d74484d58e82be9b8e7357, since
  we lack the flow dissector flags in this release we guard the
  flow label access using a test on 'skb' being NULL ]

This patch fixes an issue with unaligned accesses when using
eth_get_headlen on a page that was DMA aligned instead of being IP aligned.
The fact is when trying to check the length we don't need to be looking at
the flow label so we can reorder the checks to first check if we are
supposed to gather the flow label and then make the call to actually get
it.

v2:  Updated path so that either STOP_AT_FLOW_LABEL or KEY_FLOW_LABEL can
     cause us to check for the flow label.

Reported-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agosctp: translate network order to host order when users get a hmacid
Xin Long [Wed, 3 Feb 2016 15:33:30 +0000 (23:33 +0800)]
sctp: translate network order to host order when users get a hmacid

[ Upstream commit 7a84bd46647ff181eb2659fdc99590e6f16e501d ]

Commit ed5a377d87dc ("sctp: translate host order to network order when
setting a hmacid") corrected the hmacid byte-order when setting a hmacid.
but the same issue also exists on getting a hmacid.

We fix it by changing hmacids to host order when users get them with
getsockopt.

Fixes: Commit ed5a377d87dc ("sctp: translate host order to network order when setting a hmacid")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agotg3: Fix for tg3 transmit queue 0 timed out when too many gso_segs
Siva Reddy Kallam [Wed, 3 Feb 2016 08:39:38 +0000 (14:09 +0530)]
tg3: Fix for tg3 transmit queue 0 timed out when too many gso_segs

[ Upstream commit b7d987295c74500b733a0ba07f9a9bcc4074fa83 ]

tg3_tso_bug() can hit a condition where the entire tx ring is not big
enough to segment the GSO packet. For example, if MSS is very small,
gso_segs can exceed the tx ring size. When we hit the condition, it
will cause tx timeout.

tg3_tso_bug() is called to handle TSO and DMA hardware bugs.
For TSO bugs, if tg3_tso_bug() cannot succeed, we have to drop the packet.
For DMA bugs, we can still fall back to linearize the SKB and let the
hardware transmit the TSO packet.

This patch adds a function tg3_tso_bug_gso_check() to check if there
are enough tx descriptors for GSO before calling tg3_tso_bug().
The caller will then handle the error appropriately - drop or
lineraize the SKB.

v2: Corrected patch description to avoid confusion.

Signed-off-by: Siva Reddy Kallam <siva.kallam@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Acked-by: Prashant Sreedharan <prashant@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agonet:Add sysctl_max_skb_frags
Hans Westgaard Ry [Wed, 3 Feb 2016 08:26:57 +0000 (09:26 +0100)]
net:Add sysctl_max_skb_frags

[ Upstream commit 5f74f82ea34c0da80ea0b49192bb5ea06e063593 ]

Devices may have limits on the number of fragments in an skb they support.
Current codebase uses a constant as maximum for number of fragments one
skb can hold and use.
When enabling scatter/gather and running traffic with many small messages
the codebase uses the maximum number of fragments and may thereby violate
the max for certain devices.
The patch introduces a global variable as max number of fragments.

Signed-off-by: Hans Westgaard Ry <hans.westgaard.ry@oracle.com>
Reviewed-by: Håkon Bugge <haakon.bugge@oracle.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agounix: correctly track in-flight fds in sending process user_struct
Hannes Frederic Sowa [Wed, 3 Feb 2016 01:11:03 +0000 (02:11 +0100)]
unix: correctly track in-flight fds in sending process user_struct

[ Upstream commit 415e3d3e90ce9e18727e8843ae343eda5a58fad6 ]

The commit referenced in the Fixes tag incorrectly accounted the number
of in-flight fds over a unix domain socket to the original opener
of the file-descriptor. This allows another process to arbitrary
deplete the original file-openers resource limit for the maximum of
open files. Instead the sending processes and its struct cred should
be credited.

To do so, we add a reference counted struct user_struct pointer to the
scm_fp_list and use it to account for the number of inflight unix fds.

Fixes: 712f4aad406bb1 ("unix: properly account for FDs passed over unix sockets")
Reported-by: David Herrmann <dh.herrmann@gmail.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoipv6: fix a lockdep splat
Eric Dumazet [Wed, 3 Feb 2016 01:55:01 +0000 (17:55 -0800)]
ipv6: fix a lockdep splat

[ Upstream commit 44c3d0c1c0a880354e9de5d94175742e2c7c9683 ]

Silence lockdep false positive about rcu_dereference() being
used in the wrong context.

First one should use rcu_dereference_protected() as we own the spinlock.

Second one should be a normal assignation, as no barrier is needed.

Fixes: 18367681a10bd ("ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.")
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoipv6: addrconf: Fix recursive spin lock call
subashab@codeaurora.org [Tue, 2 Feb 2016 02:11:10 +0000 (02:11 +0000)]
ipv6: addrconf: Fix recursive spin lock call

[ Upstream commit 16186a82de1fdd868255448274e64ae2616e2640 ]

A rcu stall with the following backtrace was seen on a system with
forwarding, optimistic_dad and use_optimistic set. To reproduce,
set these flags and allow ipv6 autoconf.

This occurs because the device write_lock is acquired while already
holding the read_lock. Back trace below -

INFO: rcu_preempt self-detected stall on CPU { 1}  (t=2100 jiffies
 g=3992 c=3991 q=4471)
<6> Task dump for CPU 1:
<2> kworker/1:0     R  running task    12168    15   2 0x00000002
<2> Workqueue: ipv6_addrconf addrconf_dad_work
<6> Call trace:
<2> [<ffffffc000084da8>] el1_irq+0x68/0xdc
<2> [<ffffffc000cc4e0c>] _raw_write_lock_bh+0x20/0x30
<2> [<ffffffc000bc5dd8>] __ipv6_dev_ac_inc+0x64/0x1b4
<2> [<ffffffc000bcbd2c>] addrconf_join_anycast+0x9c/0xc4
<2> [<ffffffc000bcf9f0>] __ipv6_ifa_notify+0x160/0x29c
<2> [<ffffffc000bcfb7c>] ipv6_ifa_notify+0x50/0x70
<2> [<ffffffc000bd035c>] addrconf_dad_work+0x314/0x334
<2> [<ffffffc0000b64c8>] process_one_work+0x244/0x3fc
<2> [<ffffffc0000b7324>] worker_thread+0x2f8/0x418
<2> [<ffffffc0000bb40c>] kthread+0xe0/0xec

v2: do addrconf_dad_kick inside read lock and then acquire write
lock for ipv6_ifa_notify as suggested by Eric

Fixes: 7fd2561e4ebdd ("net: ipv6: Add a sysctl to make optimistic
addresses useful candidates")

Cc: Eric Dumazet <edumazet@google.com>
Cc: Erik Kline <ek@google.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agonet/ipv6: add sysctl option accept_ra_min_hop_limit
Hangbin Liu [Thu, 30 Jul 2015 06:28:42 +0000 (14:28 +0800)]
net/ipv6: add sysctl option accept_ra_min_hop_limit

[ Upstream commit 8013d1d7eafb0589ca766db6b74026f76b7f5cb4 ]

Commit 6fd99094de2b ("ipv6: Don't reduce hop limit for an interface")
disabled accept hop limit from RA if it is smaller than the current hop
limit for security stuff. But this behavior kind of break the RFC definition.

RFC 4861, 6.3.4.  Processing Received Router Advertisements
   A Router Advertisement field (e.g., Cur Hop Limit, Reachable Time,
   and Retrans Timer) may contain a value denoting that it is
   unspecified.  In such cases, the parameter should be ignored and the
   host should continue using whatever value it is already using.

   If the received Cur Hop Limit value is non-zero, the host SHOULD set
   its CurHopLimit variable to the received value.

So add sysctl option accept_ra_min_hop_limit to let user choose the minimum
hop limit value they can accept from RA. And set default to 1 to meet RFC
standards.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoipv6/udp: use sticky pktinfo egress ifindex on connect()
Paolo Abeni [Fri, 29 Jan 2016 11:30:20 +0000 (12:30 +0100)]
ipv6/udp: use sticky pktinfo egress ifindex on connect()

[ Upstream commit 1cdda91871470f15e79375991bd2eddc6e86ddb1 ]

Currently, the egress interface index specified via IPV6_PKTINFO
is ignored by __ip6_datagram_connect(), so that RFC 3542 section 6.7
can be subverted when the user space application calls connect()
before sendmsg().
Fix it by initializing properly flowi6_oif in connect() before
performing the route lookup.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoipv6: enforce flowi6_oif usage in ip6_dst_lookup_tail()
Paolo Abeni [Fri, 29 Jan 2016 11:30:19 +0000 (12:30 +0100)]
ipv6: enforce flowi6_oif usage in ip6_dst_lookup_tail()

[ Upstream commit 6f21c96a78b835259546d8f3fb4edff0f651d478 ]

The current implementation of ip6_dst_lookup_tail basically
ignore the egress ifindex match: if the saddr is set,
ip6_route_output() purposefully ignores flowi6_oif, due
to the commit d46a9d678e4c ("net: ipv6: Dont add RT6_LOOKUP_F_IFACE
flag if saddr set"), if the saddr is 'any' the first route lookup
in ip6_dst_lookup_tail fails, but upon failure a second lookup will
be performed with saddr set, thus ignoring the ifindex constraint.

This commit adds an output route lookup function variant, which
allows the caller to specify lookup flags, and modify
ip6_dst_lookup_tail() to enforce the ifindex match on the second
lookup via said helper.

ip6_route_output() becames now a static inline function build on
top of ip6_route_output_flags(); as a side effect, out-of-tree
modules need now a GPL license to access the output route lookup
functionality.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agotcp: beware of alignments in tcp_get_info()
Eric Dumazet [Wed, 27 Jan 2016 18:52:43 +0000 (10:52 -0800)]
tcp: beware of alignments in tcp_get_info()

[ Upstream commit ff5d749772018602c47509bdc0093ff72acd82ec ]

With some combinations of user provided flags in netlink command,
it is possible to call tcp_get_info() with a buffer that is not 8-bytes
aligned.

It does matter on some arches, so we need to use put_unaligned() to
store the u64 fields.

Current iproute2 package does not trigger this particular issue.

Fixes: 0df48c26d841 ("tcp: add tcpi_bytes_acked to tcp_info")
Fixes: 977cb0ecf82e ("tcp: add pacing_rate information into tcp_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoswitchdev: Require RTNL mutex to be held when sending FDB notifications
Ido Schimmel [Wed, 27 Jan 2016 14:16:43 +0000 (15:16 +0100)]
switchdev: Require RTNL mutex to be held when sending FDB notifications

[ Upstream commit 4f2c6ae5c64c353fb1b0425e4747e5603feadba1 ]

When switchdev drivers process FDB notifications from the underlying
device they resolve the netdev to which the entry points to and notify
the bridge using the switchdev notifier.

However, since the RTNL mutex is not held there is nothing preventing
the netdev from disappearing in the middle, which will cause
br_switchdev_event() to dereference a non-existing netdev.

Make switchdev drivers hold the lock at the beginning of the
notification processing session and release it once it ends, after
notifying the bridge.

Also, remove switchdev_mutex and fdb_lock, as they are no longer needed
when RTNL mutex is held.

Fixes: 03bf0c281234 ("switchdev: introduce switchdev notifier")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agotipc: fix connection abort during subscription cancel
Parthasarathy Bhuvaragan [Wed, 27 Jan 2016 10:35:59 +0000 (11:35 +0100)]
tipc: fix connection abort during subscription cancel

[ Upstream commit 4d5cfcba2f6ec494d8810b9e3c0a7b06255c8067 ]

In 'commit 7fe8097cef5f ("tipc: fix nullpointer bug when subscribing
to events")', we terminate the connection if the subscription
creation fails.
In the same commit, the subscription creation result was based on
the value of the subscription pointer (set in the function) instead
of the return code.

Unfortunately, the same function tipc_subscrp_create() handles
subscription cancel request. For a subscription cancellation request,
the subscription pointer cannot be set. Thus if a subscriber has
several subscriptions and cancels any of them, the connection is
terminated.

In this commit, we terminate the connection based on the return value
of tipc_subscrp_create().
Fixes: commit 7fe8097cef5f ("tipc: fix nullpointer bug when subscribing to events")
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agosctp: allow setting SCTP_SACK_IMMEDIATELY by the application
Marcelo Ricardo Leitner [Fri, 22 Jan 2016 20:29:49 +0000 (18:29 -0200)]
sctp: allow setting SCTP_SACK_IMMEDIATELY by the application

[ Upstream commit 27f7ed2b11d42ab6d796e96533c2076ec220affc ]

This patch extends commit b93d6471748d ("sctp: implement the sender side
for SACK-IMMEDIATELY extension") as it didn't white list
SCTP_SACK_IMMEDIATELY on sctp_msghdr_parse(), causing it to be
understood as an invalid flag and returning -EINVAL to the application.

Note that the actual handling of the flag is already there in
sctp_datamsg_from_user().

https://tools.ietf.org/html/rfc7053#section-7

Fixes: b93d6471748d ("sctp: implement the sender side for SACK-IMMEDIATELY extension")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agopptp: fix illegal memory access caused by multiple bind()s
Hannes Frederic Sowa [Fri, 22 Jan 2016 00:39:43 +0000 (01:39 +0100)]
pptp: fix illegal memory access caused by multiple bind()s

[ Upstream commit 9a368aff9cb370298fa02feeffa861f2db497c18 ]

Several times already this has been reported as kasan reports caused by
syzkaller and trinity and people always looked at RCU races, but it is
much more simple. :)

In case we bind a pptp socket multiple times, we simply add it to
the callid_sock list but don't remove the old binding. Thus the old
socket stays in the bucket with unused call_id indexes and doesn't get
cleaned up. This causes various forms of kasan reports which were hard
to pinpoint.

Simply don't allow multiple binds and correct error handling in
pptp_bind. Also keep sk_state bits in place in pptp_connect.

Fixes: 00959ade36acad ("PPTP: PPP over IPv4 (Point-to-Point Tunneling Protocol)")
Cc: Dmitry Kozlov <xeb@mail.ru>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoaf_unix: fix struct pid memory leak
Eric Dumazet [Sun, 24 Jan 2016 21:53:50 +0000 (13:53 -0800)]
af_unix: fix struct pid memory leak

[ Upstream commit fa0dc04df259ba2df3ce1920e9690c7842f8fa4b ]

Dmitry reported a struct pid leak detected by a syzkaller program.

Bug happens in unix_stream_recvmsg() when we break the loop when a
signal is pending, without properly releasing scm.

Fixes: b3ca9b02b007 ("net: fix multithreaded signal handling in unix recv routines")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agotcp: fix NULL deref in tcp_v4_send_ack()
Eric Dumazet [Thu, 21 Jan 2016 16:02:54 +0000 (08:02 -0800)]
tcp: fix NULL deref in tcp_v4_send_ack()

[ Upstream commit e62a123b8ef7c5dc4db2c16383d506860ad21b47 ]

Neal reported crashes with this stack trace :

 RIP: 0010:[<ffffffff8c57231b>] tcp_v4_send_ack+0x41/0x20f
...
 CR2: 0000000000000018 CR3: 000000044005c000 CR4: 00000000001427e0
...
  [<ffffffff8c57258e>] tcp_v4_reqsk_send_ack+0xa5/0xb4
  [<ffffffff8c1a7caa>] tcp_check_req+0x2ea/0x3e0
  [<ffffffff8c19e420>] tcp_rcv_state_process+0x850/0x2500
  [<ffffffff8c1a6d21>] tcp_v4_do_rcv+0x141/0x330
  [<ffffffff8c56cdb2>] sk_backlog_rcv+0x21/0x30
  [<ffffffff8c098bbd>] tcp_recvmsg+0x75d/0xf90
  [<ffffffff8c0a8700>] inet_recvmsg+0x80/0xa0
  [<ffffffff8c17623e>] sock_aio_read+0xee/0x110
  [<ffffffff8c066fcf>] do_sync_read+0x6f/0xa0
  [<ffffffff8c0673a1>] SyS_read+0x1e1/0x290
  [<ffffffff8c5ca262>] system_call_fastpath+0x16/0x1b

The problem here is the skb we provide to tcp_v4_send_ack() had to
be parked in the backlog of a new TCP fastopen child because this child
was owned by the user at the time an out of window packet arrived.

Before queuing a packet, TCP has to set skb->dev to NULL as the device
could disappear before packet is removed from the queue.

Fix this issue by using the net pointer provided by the socket (being a
timewait or a request socket).

IPv6 is immune to the bug : tcp_v6_send_response() already gets the net
pointer from the socket if provided.

Fixes: 168a8f58059a ("tcp: TCP Fast Open Server - main code path")
Reported-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jerry Chu <hkchu@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agonet: dp83640: Fix tx timestamp overflow handling.
Manfred Rudigier [Wed, 20 Jan 2016 10:22:28 +0000 (11:22 +0100)]
net: dp83640: Fix tx timestamp overflow handling.

[ Upstream commit 81e8f2e930fe76b9814c71b9d87c30760b5eb705 ]

PHY status frames are not reliable, the PHY may not be able to send them
during heavy receive traffic. This overflow condition is signaled by the
PHY in the next status frame, but the driver did not make use of it.
Instead it always reported wrong tx timestamps to user space after an
overflow happened because it assigned newly received tx timestamps to old
packets in the queue.

This commit fixes this issue by clearing the tx timestamp queue every time
an overflow happens, so that no timestamps are delivered for overflow
packets. This way time stamping will continue correctly after an overflow.

Signed-off-by: Manfred Rudigier <manfred.rudigier@omicron.at>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoaf_iucv: Validate socket address length in iucv_sock_bind()
Ursula Braun [Tue, 19 Jan 2016 09:41:33 +0000 (10:41 +0100)]
af_iucv: Validate socket address length in iucv_sock_bind()

[ Upstream commit 52a82e23b9f2a9e1d429c5207f8575784290d008 ]

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Evgeny Cherkashin <Eugene.Crosser@ru.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agopowerpc/eeh: Fix build error caused by pci_dn
Gavin Shan [Tue, 1 Mar 2016 05:02:43 +0000 (16:02 +1100)]
powerpc/eeh: Fix build error caused by pci_dn

eeh.h could be included when we have following condition. Then we
run into build error as below: (CONFIG_PPC64 && !CONFIG_EEH) ||
(!CONFIG_PPC64 && !CONFIG_EEH)

In file included from arch/powerpc/kernel/of_platform.c:30:0:
./arch/powerpc/include/asm/eeh.h:344:48: error: ‘struct pci_dn’ \
declared inside parameter list [-Werror]
    :
In file included from arch/powerpc/mm/hash_utils_64.c:49:0:
./arch/powerpc/include/asm/eeh.h:344:48: error: ‘struct pci_dn’ \
declared inside parameter list [-Werror]

This fixes the issue by replacing those empty inline functions
with macro so that we don't rely on @pci_dn when CONFIG_EEH is
disabled.

Cc: stable@vger.kernel.org # v4.1+
Fixes: ff57b45 ("powerpc/eeh: Do probe on pci_dn")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoext4: fix crashes in dioread_nolock mode
Jan Kara [Fri, 19 Feb 2016 05:33:21 +0000 (00:33 -0500)]
ext4: fix crashes in dioread_nolock mode

[ Upstream commit 74dae4278546b897eb81784fdfcce872ddd8b2b8 ]

Competing overwrite DIO in dioread_nolock mode will just overwrite
pointer to io_end in the inode. This may result in data corruption or
extent conversion happening from IO completion interrupt because we
don't properly set buffer_defer_completion() when unlocked DIO races
with locked DIO to unwritten extent.

Since unlocked DIO doesn't need io_end for anything, just avoid
allocating it and corrupting pointer from inode for locked DIO.
A cleaner fix would be to avoid these games with io_end pointer from the
inode but that requires more intrusive changes so we leave that for
later.

Cc: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoipc/shm: handle removed segments gracefully in shm_mmap()
Kirill A. Shutemov [Wed, 17 Feb 2016 21:11:35 +0000 (13:11 -0800)]
ipc/shm: handle removed segments gracefully in shm_mmap()

[ Upstream commit 15db15e2f10ae12d021c9a2e9edd8a03b9238551 ]

commit 1ac0b6dec656f3f78d1c3dd216fad84cb4d0a01e upstream.

remap_file_pages(2) emulation can reach file which represents removed
IPC ID as long as a memory segment is mapped.  It breaks expectations of
IPC subsystem.

Test case (rewritten to be more human readable, originally autogenerated
by syzkaller[1]):

#define _GNU_SOURCE
#include <stdlib.h>
#include <sys/ipc.h>
#include <sys/mman.h>
#include <sys/shm.h>

#define PAGE_SIZE 4096

int main()
{
int id;
void *p;

id = shmget(IPC_PRIVATE, 3 * PAGE_SIZE, 0);
p = shmat(id, NULL, 0);
shmctl(id, IPC_RMID, NULL);
remap_file_pages(p, 3 * PAGE_SIZE, 0, 7, 0);

        return 0;
}

The patch changes shm_mmap() and code around shm_lock() to propagate
locking error back to caller of shm_mmap().

[1] http://github.com/google/syzkaller

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoipc: convert invalid scenarios to use WARN_ON
Davidlohr Bueso [Wed, 9 Sep 2015 22:39:20 +0000 (15:39 -0700)]
ipc: convert invalid scenarios to use WARN_ON

[ Upstream commit d0edd8528362c07216498340e928159510595e7b ]

Considering Linus' past rants about the (ab)use of BUG in the kernel, I
took a look at how we deal with such calls in ipc.  Given that any errors
or corruption in ipc code are most likely contained within the set of
processes participating in the broken mechanisms, there aren't really many
strong fatal system failure scenarios that would require a BUG call.
Also, if something is seriously wrong, ipc might not be the place for such
a BUG either.

1. For example, recently, a customer hit one of these BUG_ONs in shm
   after failing shm_lock().  A busted ID imho does not merit a BUG_ON,
   and WARN would have been better.

2. MSG_COPY functionality of posix msgrcv(2) for checkpoint/restore.
   I don't see how we can hit this anyway -- at least it should be IS_ERR.
    The 'copy' arg from do_msgrcv is always set by calling prepare_copy()
   first and foremost.  We could also probably drop this check altogether.
    Either way, it does not merit a BUG_ON.

3. No ->fault() callback for the fs getting the corresponding page --
   seems selfish to make the system unusable.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoipc,shm: move BUG_ON check into shm_lock
Davidlohr Bueso [Tue, 30 Jun 2015 21:58:36 +0000 (14:58 -0700)]
ipc,shm: move BUG_ON check into shm_lock

[ Upstream commit c5c8975b2eb4eb7604e8ce4f762987f56d2a96a2 ]

Upon every shm_lock call, we BUG_ON if an error was returned, indicating
racing either in idr or in shm_destroy.  Move this logic into the locking.

[akpm@linux-foundation.org: simplify code]
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agomm: fix regression in remap_file_pages() emulation
Kirill A. Shutemov [Wed, 17 Feb 2016 21:11:15 +0000 (13:11 -0800)]
mm: fix regression in remap_file_pages() emulation

[ Upstream commit 48f7df329474b49d83d0dffec1b6186647f11976 ]

Grazvydas Ignotas has reported a regression in remap_file_pages()
emulation.

Testcase:
#define _GNU_SOURCE
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/mman.h>

#define SIZE    (4096 * 3)

int main(int argc, char **argv)
{
unsigned long *p;
long i;

p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS, -1, 0);
if (p == MAP_FAILED) {
perror("mmap");
return -1;
}

for (i = 0; i < SIZE / 4096; i++)
p[i * 4096 / sizeof(*p)] = i;

if (remap_file_pages(p, 4096, 0, 1, 0)) {
perror("remap_file_pages");
return -1;
}

if (remap_file_pages(p, 4096 * 2, 0, 1, 0)) {
perror("remap_file_pages");
return -1;
}

assert(p[0] == 1);

munmap(p, SIZE);

return 0;
}

The second remap_file_pages() fails with -EINVAL.

The reason is that remap_file_pages() emulation assumes that the target
vma covers whole area we want to over map.  That assumption is broken by
first remap_file_pages() call: it split the area into two vma.

The solution is to check next adjacent vmas, if they map the same file
with the same flags.

Fixes: c8d78c1823f4 ("mm: replace remap_file_pages() syscall with emulation")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Grazvydas Ignotas <notasas@gmail.com>
Tested-by: Grazvydas Ignotas <notasas@gmail.com>
Cc: <stable@vger.kernel.org> [4.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: pcm: Fix rwsem deadlock for non-atomic PCM stream
Takashi Iwai [Wed, 17 Feb 2016 13:30:26 +0000 (14:30 +0100)]
ALSA: pcm: Fix rwsem deadlock for non-atomic PCM stream

[ Upstream commit 67ec1072b053c15564e6090ab30127895dc77a89 ]

A non-atomic PCM stream may take snd_pcm_link_rwsem rw semaphore twice
in the same code path, e.g. one in snd_pcm_action_nonatomic() and
another in snd_pcm_stream_lock().  Usually this is OK, but when a
write lock is issued between these two read locks, the problem
happens: the write lock is blocked due to the first reade lock, and
the second read lock is also blocked by the write lock.  This
eventually deadlocks.

The reason is the way rwsem manages waiters; it's queued like FIFO, so
even if the writer itself doesn't take the lock yet, it blocks all the
waiters (including reads) queued after it.

As a workaround, in this patch, we replace the standard down_write()
with an spinning loop.  This is far from optimal, but it's good
enough, as the spinning time is supposed to be relatively short for
normal PCM operations, and the code paths requiring the write lock
aren't called so often.

Reported-by: Vinod Koul <vinod.koul@intel.com>
Tested-by: Ramesh Babu <ramesh.babu@intel.com>
Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agox86/mm: Fix vmalloc_fault() to handle large pages properly
Toshi Kani [Thu, 18 Feb 2016 01:16:54 +0000 (18:16 -0700)]
x86/mm: Fix vmalloc_fault() to handle large pages properly

[ Upstream commit f4eafd8bcd5229e998aa252627703b8462c3b90f ]

A kernel page fault oops with the callstack below was observed
when a read syscall was made to a pmem device after a huge amount
(>512GB) of vmalloc ranges was allocated by ioremap() on a x86_64
system:

     BUG: unable to handle kernel paging request at ffff880840000ff8
     IP: vmalloc_fault+0x1be/0x300
     PGD c7f03a067 PUD 0
     Oops: 0000 [#1] SM
     Call Trace:
        __do_page_fault+0x285/0x3e0
        do_page_fault+0x2f/0x80
        ? put_prev_entity+0x35/0x7a0
        page_fault+0x28/0x30
        ? memcpy_erms+0x6/0x10
        ? schedule+0x35/0x80
        ? pmem_rw_bytes+0x6a/0x190 [nd_pmem]
        ? schedule_timeout+0x183/0x240
        btt_log_read+0x63/0x140 [nd_btt]
         :
        ? __symbol_put+0x60/0x60
        ? kernel_read+0x50/0x80
        SyS_finit_module+0xb9/0xf0
        entry_SYSCALL_64_fastpath+0x1a/0xa4

Since v4.1, ioremap() supports large page (pud/pmd) mappings in
x86_64 and PAE.  vmalloc_fault() however assumes that the vmalloc
range is limited to pte mappings.

vmalloc faults do not normally happen in ioremap'd ranges since
ioremap() sets up the kernel page tables, which are shared by
user processes.  pgd_ctor() sets the kernel's PGD entries to
user's during fork().  When allocation of the vmalloc ranges
crosses a 512GB boundary, ioremap() allocates a new pud table
and updates the kernel PGD entry to point it.  If user process's
PGD entry does not have this update yet, a read/write syscall
to the range will cause a vmalloc fault, which hits the Oops
above as it does not handle a large page properly.

Following changes are made to vmalloc_fault().

64-bit:

 - No change for the PGD sync operation as it handles large
   pages already.
 - Add pud_huge() and pmd_huge() to the validation code to
   handle large pages.
 - Change pud_page_vaddr() to pud_pfn() since an ioremap range
   is not directly mapped (while the if-statement still works
   with a bogus addr).
 - Change pmd_page() to pmd_pfn() since an ioremap range is not
   backed by struct page (while the if-statement still works
   with a bogus addr).

32-bit:
 - No change for the sync operation since the index3 PGD entry
   covers the entire vmalloc range, which is always valid.
   (A separate change to sync PGD entry is necessary if this
    memory layout is changed regardless of the page size.)
 - Add pmd_huge() to the validation code to handle large pages.
   This is for completeness since vmalloc_fault() won't happen
   in ioremap'd ranges as its PGD entry is always valid.

Reported-by: Henning Schild <henning.schild@siemens.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: <stable@vger.kernel.org> # 4.1+
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-mm@kvack.org
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/1455758214-24623-1-git-send-email-toshi.kani@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agodrm/qxl: use kmalloc_array to alloc reloc_info in qxl_process_single_command
Gerd Hoffmann [Tue, 16 Feb 2016 13:25:00 +0000 (14:25 +0100)]
drm/qxl: use kmalloc_array to alloc reloc_info in qxl_process_single_command

[ Upstream commit 34855706c30d52b0a744da44348b5d1cc39fbe51 ]

This avoids integer overflows on 32bit machines when calculating
reloc_info size, as reported by Alan Cox.

Cc: stable@vger.kernel.org
Cc: gnomes@lxorguk.ukuu.org.uk
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agodrm/radeon: use post-decrement in error handling
Rasmus Villemoes [Mon, 15 Feb 2016 18:41:47 +0000 (19:41 +0100)]
drm/radeon: use post-decrement in error handling

[ Upstream commit bc3f5d8c4ca01555820617eb3b6c0857e4df710d ]

We need to use post-decrement to get the pci_map_page undone also for
i==0, and to avoid some very unpleasant behaviour if pci_map_page
failed already at i==0.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: seq: Fix double port list deletion
Takashi Iwai [Tue, 16 Feb 2016 13:15:59 +0000 (14:15 +0100)]
ALSA: seq: Fix double port list deletion

[ Upstream commit 13d5e5d4725c64ec06040d636832e78453f477b7 ]

The commit [7f0973e973cd: ALSA: seq: Fix lockdep warnings due to
double mutex locks] split the management of two linked lists (source
and destination) into two individual calls for avoiding the AB/BA
deadlock.  However, this may leave the possible double deletion of one
of two lists when the counterpart is being deleted concurrently.
It ends up with a list corruption, as revealed by syzkaller fuzzer.

This patch fixes it by checking the list emptiness and skipping the
deletion and the following process.

BugLink: http://lkml.kernel.org/r/CACT4Y+bay9qsrz6dQu31EcGaH9XwfW7o3oBzSQUG9fMszoh=Sg@mail.gmail.com
Fixes: 7f0973e973cd ('ALSA: seq: Fix lockdep warnings due to 'double mutex locks)
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agotracing: Fix freak link error caused by branch tracer
Arnd Bergmann [Fri, 12 Feb 2016 21:26:42 +0000 (22:26 +0100)]
tracing: Fix freak link error caused by branch tracer

[ Upstream commit b33c8ff4431a343561e2319f17c14286f2aa52e2 ]

In my randconfig tests, I came across a bug that involves several
components:

* gcc-4.9 through at least 5.3
* CONFIG_GCOV_PROFILE_ALL enabling -fprofile-arcs for all files
* CONFIG_PROFILE_ALL_BRANCHES overriding every if()
* The optimized implementation of do_div() that tries to
  replace a library call with an division by multiplication
* code in drivers/media/dvb-frontends/zl10353.c doing

        u32 adc_clock = 450560; /* 45.056 MHz */
        if (state->config.adc_clock)
                adc_clock = state->config.adc_clock;
        do_div(value, adc_clock);

In this case, gcc fails to determine whether the divisor
in do_div() is __builtin_constant_p(). In particular, it
concludes that __builtin_constant_p(adc_clock) is false, while
__builtin_constant_p(!!adc_clock) is true.

That in turn throws off the logic in do_div() that also uses
__builtin_constant_p(), and instead of picking either the
constant- optimized division, and the code in ilog2() that uses
__builtin_constant_p() to figure out whether it knows the answer at
compile time. The result is a link error from failing to find
multiple symbols that should never have been called based on
the __builtin_constant_p():

dvb-frontends/zl10353.c:138: undefined reference to `____ilog2_NaN'
dvb-frontends/zl10353.c:138: undefined reference to `__aeabi_uldivmod'
ERROR: "____ilog2_NaN" [drivers/media/dvb-frontends/zl10353.ko] undefined!
ERROR: "__aeabi_uldivmod" [drivers/media/dvb-frontends/zl10353.ko] undefined!

This patch avoids the problem by changing __trace_if() to check
whether the condition is known at compile-time to be nonzero, rather
than checking whether it is actually a constant.

I see this one link error in roughly one out of 1600 randconfig builds
on ARM, and the patch fixes all known instances.

Link: http://lkml.kernel.org/r/1455312410-1058841-1-git-send-email-arnd@arndb.de
Acked-by: Nicolas Pitre <nico@linaro.org>
Fixes: ab3c9c686e22 ("branch tracer, intel-iommu: fix build with CONFIG_BRANCH_TRACER=y")
Cc: stable@vger.kernel.org # v2.6.30+
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agotracepoints: Do not trace when cpu is offline
Steven Rostedt (Red Hat) [Mon, 15 Feb 2016 17:36:14 +0000 (12:36 -0500)]
tracepoints: Do not trace when cpu is offline

[ Upstream commit f37755490fe9bf76f6ba1d8c6591745d3574a6a6 ]

The tracepoint infrastructure uses RCU sched protection to enable and
disable tracepoints safely. There are some instances where tracepoints are
used in infrastructure code (like kfree()) that get called after a CPU is
going offline, and perhaps when it is coming back online but hasn't been
registered yet.

This can probuce the following warning:

 [ INFO: suspicious RCU usage. ]
 4.4.0-00006-g0fe53e8-dirty #34 Tainted: G S
 -------------------------------
 include/trace/events/kmem.h:141 suspicious rcu_dereference_check() usage!

 other info that might help us debug this:

 RCU used illegally from offline CPU!  rcu_scheduler_active = 1, debug_locks = 1
 no locks held by swapper/8/0.

 stack backtrace:
  CPU: 8 PID: 0 Comm: swapper/8 Tainted: G S              4.4.0-00006-g0fe53e8-dirty #34
  Call Trace:
  [c0000005b76c78d0] [c0000000008b9540] .dump_stack+0x98/0xd4 (unreliable)
  [c0000005b76c7950] [c00000000010c898] .lockdep_rcu_suspicious+0x108/0x170
  [c0000005b76c79e0] [c00000000029adc0] .kfree+0x390/0x440
  [c0000005b76c7a80] [c000000000055f74] .destroy_context+0x44/0x100
  [c0000005b76c7b00] [c0000000000934a0] .__mmdrop+0x60/0x150
  [c0000005b76c7b90] [c0000000000e3ff0] .idle_task_exit+0x130/0x140
  [c0000005b76c7c20] [c000000000075804] .pseries_mach_cpu_die+0x64/0x310
  [c0000005b76c7cd0] [c000000000043e7c] .cpu_die+0x3c/0x60
  [c0000005b76c7d40] [c0000000000188d8] .arch_cpu_idle_dead+0x28/0x40
  [c0000005b76c7db0] [c000000000101e6c] .cpu_startup_entry+0x50c/0x560
  [c0000005b76c7ed0] [c000000000043bd8] .start_secondary+0x328/0x360
  [c0000005b76c7f90] [c000000000008a6c] start_secondary_prolog+0x10/0x14

This warning is not a false positive either. RCU is not protecting code that
is being executed while the CPU is offline.

Instead of playing "whack-a-mole(TM)" and adding conditional statements to
the tracepoints we find that are used in this instance, simply add a
cpu_online() test to the tracepoint code where the tracepoint will be
ignored if the CPU is offline.

Use of raw_smp_processor_id() is fine, as there should never be a case where
the tracepoint code goes from running on a CPU that is online and suddenly
gets migrated to a CPU that is offline.

Link: http://lkml.kernel.org/r/1455387773-4245-1-git-send-email-kda@linux-powerpc.org
Reported-by: Denis Kirjanov <kda@linux-powerpc.org>
Fixes: 97e1c18e8d17b ("tracing: Kernel Tracepoints")
Cc: stable@vger.kernel.org # v2.6.28+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agodmaengine: dw: disable BLOCK IRQs for non-cyclic xfer
Andy Shevchenko [Wed, 10 Feb 2016 13:59:42 +0000 (15:59 +0200)]
dmaengine: dw: disable BLOCK IRQs for non-cyclic xfer

[ Upstream commit ee1cdcdae59563535485a5f56ee72c894ab7d7ad ]

The commit 2895b2cad6e7 ("dmaengine: dw: fix cyclic transfer callbacks")
re-enabled BLOCK interrupts with regard to make cyclic transfers work. However,
this change becomes a regression for non-cyclic transfers as interrupt counters
under stress test had been grown enormously (approximately per 4-5 bytes in the
UART loop back test).

Taking into consideration above enable BLOCK interrupts if and only if channel
is programmed to perform cyclic transfer.

Fixes: 2895b2cad6e7 ("dmaengine: dw: fix cyclic transfer callbacks")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mans Rullgard <mans@mansr.com>
Tested-by: Mans Rullgard <mans@mansr.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: hda - Cancel probe work instead of flush at remove
Takashi Iwai [Mon, 15 Feb 2016 15:37:24 +0000 (16:37 +0100)]
ALSA: hda - Cancel probe work instead of flush at remove

[ Upstream commit 0b8c82190c12e530eb6003720dac103bf63e146e ]

The commit [991f86d7ae4e: ALSA: hda - Flush the pending probe work at
remove] introduced the sync of async probe work at remove for fixing
the race.  However, this may lead to another hangup when the module
removal is performed quickly before starting the probe work, because
it issues flush_work() and it's blocked forever.

The workaround is to use cancel_work_sync() instead of flush_work()
there.

Fixes: 991f86d7ae4e ('ALSA: hda - Flush the pending probe work at remove')
Cc: <stable@vger.kernel.org> # v3.17+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: seq: Fix leak of pool buffer at concurrent writes
Takashi Iwai [Mon, 15 Feb 2016 15:20:24 +0000 (16:20 +0100)]
ALSA: seq: Fix leak of pool buffer at concurrent writes

[ Upstream commit d99a36f4728fcbcc501b78447f625bdcce15b842 ]

When multiple concurrent writes happen on the ALSA sequencer device
right after the open, it may try to allocate vmalloc buffer for each
write and leak some of them.  It's because the presence check and the
assignment of the buffer is done outside the spinlock for the pool.

The fix is to move the check and the assignment into the spinlock.

(The current implementation is suboptimal, as there can be multiple
 unnecessary vmallocs because the allocation is done before the check
 in the spinlock.  But the pool size is already checked beforehand, so
 this isn't a big problem; that is, the only possible path is the
 multiple writes before any pool assignment, and practically seen, the
 current coverage should be "good enough".)

The issue was triggered by syzkaller fuzzer.

BugLink: http://lkml.kernel.org/r/CACT4Y+bSzazpXNvtAr=WXaL8hptqjHwqEyFA+VN2AWEx=aurkg@mail.gmail.com
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agopowerpc/eeh: Fix stale cached primary bus
Gavin Shan [Tue, 9 Feb 2016 04:50:21 +0000 (15:50 +1100)]
powerpc/eeh: Fix stale cached primary bus

[ Upstream commit 05ba75f848647135f063199dc0e9f40fee769724 ]

When PE is created, its primary bus is cached to pe->bus. At later
point, the cached primary bus is returned from eeh_pe_bus_get().
However, we could get stale cached primary bus and run into kernel
crash in one case: full hotplug as part of fenced PHB error recovery
releases all PCI busses under the PHB at unplugging time and recreate
them at plugging time. pe->bus is still dereferencing the PCI bus
that was released.

This adds another PE flag (EEH_PE_PRI_BUS) to represent the validity
of pe->bus. pe->bus is updated when its first child EEH device is
online and the flag is set. Before unplugging in full hotplug for
error recovery, the flag is cleared.

Fixes: 8cdb2833 ("powerpc/eeh: Trace PCI bus from PE")
Cc: stable@vger.kernel.org #v3.11+
Reported-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reported-by: Pradipta Ghosh <pradghos@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: usb-audio: avoid freeing umidi object twice
Andrey Konovalov [Sat, 13 Feb 2016 08:08:06 +0000 (11:08 +0300)]
ALSA: usb-audio: avoid freeing umidi object twice

[ Upstream commit 07d86ca93db7e5cdf4743564d98292042ec21af7 ]

The 'umidi' object will be free'd on the error path by snd_usbmidi_free()
when tearing down the rawmidi interface. So we shouldn't try to free it
in snd_usbmidi_create() after having registered the rawmidi interface.

Found by KASAN.

Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agobio: return EINTR if copying to user space got interrupted
Hannes Reinecke [Fri, 12 Feb 2016 08:39:15 +0000 (09:39 +0100)]
bio: return EINTR if copying to user space got interrupted

[ Upstream commit 2d99b55d378c996b9692a0c93dd25f4ed5d58934 ]

Commit 35dc248383bbab0a7203fca4d722875bc81ef091 introduced a check for
current->mm to see if we have a user space context and only copies data
if we do. Now if an IO gets interrupted by a signal data isn't copied
into user space any more (as we don't have a user space context) but
user space isn't notified about it.

This patch modifies the behaviour to return -EINTR from bio_uncopy_user()
to notify userland that a signal has interrupted the syscall, otherwise
it could lead to a situation where the caller may get a buffer with
no data returned.

This can be reproduced by issuing SG_IO ioctl()s in one thread while
constantly sending signals to it.

Fixes: 35dc248 [SCSI] sg: Fix user memory corruption when SG_IO is interrupted by a signal
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Cc: stable@vger.kernel.org # v.3.11+
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoEVM: Use crypto_memneq() for digest comparisons
Ryan Ware [Thu, 11 Feb 2016 23:58:44 +0000 (15:58 -0800)]
EVM: Use crypto_memneq() for digest comparisons

[ Upstream commit 613317bd212c585c20796c10afe5daaa95d4b0a1 ]

This patch fixes vulnerability CVE-2016-2085.  The problem exists
because the vm_verify_hmac() function includes a use of memcmp().
Unfortunately, this allows timing side channel attacks; specifically
a MAC forgery complexity drop from 2^128 to 2^12.  This patch changes
the memcmp() to the cryptographically safe crypto_memneq().

Reported-by: Xiaofei Rex Guo <xiaofei.rex.guo@intel.com>
Signed-off-by: Ryan Ware <ware@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoext4: don't read blocks from disk after extents being swapped
Eryu Guan [Fri, 12 Feb 2016 06:20:43 +0000 (01:20 -0500)]
ext4: don't read blocks from disk after extents being swapped

[ Upstream commit bcff24887d00bce102e0857d7b0a8c44a40f53d1 ]

I notice ext4/307 fails occasionally on ppc64 host, reporting md5
checksum mismatch after moving data from original file to donor file.

The reason is that move_extent_per_page() calls __block_write_begin()
and block_commit_write() to write saved data from original inode blocks
to donor inode blocks, but __block_write_begin() not only maps buffer
heads but also reads block content from disk if the size is not block
size aligned.  At this time the physical block number in mapped buffer
head is pointing to the donor file not the original file, and that
results in reading wrong data to page, which get written to disk in
following block_commit_write call.

This also can be reproduced by the following script on 1k block size ext4
on x86_64 host:

    mnt=/mnt/ext4
    donorfile=$mnt/donor
    testfile=$mnt/testfile
    e4compact=~/xfstests/src/e4compact

    rm -f $donorfile $testfile

    # reserve space for donor file, written by 0xaa and sync to disk to
    # avoid EBUSY on EXT4_IOC_MOVE_EXT
    xfs_io -fc "pwrite -S 0xaa 0 1m" -c "fsync" $donorfile

    # create test file written by 0xbb
    xfs_io -fc "pwrite -S 0xbb 0 1023" -c "fsync" $testfile

    # compute initial md5sum
    md5sum $testfile | tee md5sum.txt
    # drop cache, force e4compact to read data from disk
    echo 3 > /proc/sys/vm/drop_caches

    # test defrag
    echo "$testfile" | $e4compact -i -v -f $donorfile
    # check md5sum
    md5sum -c md5sum.txt

Fix it by creating & mapping buffer heads only but not reading blocks
from disk, because all the data in page is guaranteed to be up-to-date
in mext_page_mkuptodate().

Cc: stable@vger.kernel.org
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoext4: fix potential integer overflow
Insu Yun [Fri, 12 Feb 2016 06:15:59 +0000 (01:15 -0500)]
ext4: fix potential integer overflow

[ Upstream commit 46901760b46064964b41015d00c140c83aa05bcf ]

Since sizeof(ext_new_group_data) > sizeof(ext_new_flex_group_data),
integer overflow could be happened.
Therefore, need to fix integer overflow sanitization.

Cc: stable@vger.kernel.org
Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agobtrfs: properly set the termination value of ctx->pos in readdir
David Sterba [Fri, 13 Nov 2015 12:44:28 +0000 (13:44 +0100)]
btrfs: properly set the termination value of ctx->pos in readdir

[ Upstream commit bc4ef7592f657ae81b017207a1098817126ad4cb ]

The value of ctx->pos in the last readdir call is supposed to be set to
INT_MAX due to 32bit compatibility, unless 'pos' is intentially set to a
larger value, then it's LLONG_MAX.

There's a report from PaX SIZE_OVERFLOW plugin that "ctx->pos++"
overflows (https://forums.grsecurity.net/viewtopic.php?f=1&t=4284), on a
64bit arch, where the value is 0x7fffffffffffffff ie. LLONG_MAX before
the increment.

We can get to that situation like that:

* emit all regular readdir entries
* still in the same call to readdir, bump the last pos to INT_MAX
* next call to readdir will not emit any entries, but will reach the
  bump code again, finds pos to be INT_MAX and sets it to LLONG_MAX

Normally this is not a problem, but if we call readdir again, we'll find
'pos' set to LLONG_MAX and the unconditional increment will overflow.

The report from Victor at
(http://thread.gmane.org/gmane.comp.file-systems.btrfs/49500) with debugging
print shows that pattern:

 Overflow: e
 Overflow: 7fffffff
 Overflow: 7fffffffffffffff
 PAX: size overflow detected in function btrfs_real_readdir
   fs/btrfs/inode.c:5760 cicus.935_282 max, count: 9, decl: pos; num: 0;
   context: dir_context;
 CPU: 0 PID: 2630 Comm: polkitd Not tainted 4.2.3-grsec #1
 Hardware name: Gigabyte Technology Co., Ltd. H81ND2H/H81ND2H, BIOS F3 08/11/2015
  ffffffff81901608 0000000000000000 ffffffff819015e6 ffffc90004973d48
  ffffffff81742f0f 0000000000000007 ffffffff81901608 ffffc90004973d78
  ffffffff811cb706 0000000000000000 ffff8800d47359e0 ffffc90004973ed8
 Call Trace:
  [<ffffffff81742f0f>] dump_stack+0x4c/0x7f
  [<ffffffff811cb706>] report_size_overflow+0x36/0x40
  [<ffffffff812ef0bc>] btrfs_real_readdir+0x69c/0x6d0
  [<ffffffff811dafc8>] iterate_dir+0xa8/0x150
  [<ffffffff811e6d8d>] ? __fget_light+0x2d/0x70
  [<ffffffff811dba3a>] SyS_getdents+0xba/0x1c0
 Overflow: 1a
  [<ffffffff811db070>] ? iterate_dir+0x150/0x150
  [<ffffffff81749b69>] entry_SYSCALL_64_fastpath+0x12/0x83

The jump from 7fffffff to 7fffffffffffffff happens when new dir entries
are not yet synced and are processed from the delayed list. Then the code
could go to the bump section again even though it might not emit any new
dir entries from the delayed list.

The fix avoids entering the "bump" section again once we've finished
emitting the entries, both for synced and delayed entries.

References: https://forums.grsecurity.net/viewtopic.php?f=1&t=4284
Reported-by: Victor <services@swwu.com>
CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.com>
Tested-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoARM: 8519/1: ICST: try other dividends than 1
Linus Walleij [Wed, 10 Feb 2016 08:25:17 +0000 (09:25 +0100)]
ARM: 8519/1: ICST: try other dividends than 1

[ Upstream commit e972c37459c813190461dabfeaac228e00aae259 ]

Since the dawn of time the ICST code has only supported divide
by one or hang in an eternal loop. Luckily we were always dividing
by one because the reference frequency for the systems using
the ICSTs is 24MHz and the [min,max] values for the PLL input
if [10,320] MHz for ICST307 and [6,200] for ICST525, so the loop
will always terminate immediately without assigning any divisor
for the reference frequency.

But for the code to make sense, let's insert the missing i++

Reported-by: David Binderman <dcb314@hotmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agos390/dasd: fix refcount for PAV reassignment
Stefan Haberland [Tue, 15 Dec 2015 09:45:05 +0000 (10:45 +0100)]
s390/dasd: fix refcount for PAV reassignment

[ Upstream commit 9d862ababb609439c5d6987f6d3ddd09e703aa0b ]

Add refcount to the DASD device when a summary unit check worker is
scheduled. This prevents that the device is set offline with worker
in place.

Cc: stable@vger.kernel.org
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agos390/dasd: prevent incorrect length error under z/VM after PAV changes
Stefan Haberland [Tue, 15 Dec 2015 09:16:43 +0000 (10:16 +0100)]
s390/dasd: prevent incorrect length error under z/VM after PAV changes

[ Upstream commit 020bf042e5b397479c1174081b935d0ff15d1a64 ]

The channel checks the specified length and the provided amount of
data for CCWs and provides an incorrect length error if the size does
not match. Under z/VM with simulation activated the length may get
changed. Having the suppress length indication bit set is stated as
good CCW coding practice and avoids errors under z/VM.

Cc: stable@vger.kernel.org
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agocifs: fix erroneous return value
Anton Protopopov [Wed, 10 Feb 2016 17:50:21 +0000 (12:50 -0500)]
cifs: fix erroneous return value

[ Upstream commit 4b550af519854421dfec9f7732cdddeb057134b2 ]

The setup_ntlmv2_rsp() function may return positive value ENOMEM instead
of -ENOMEM in case of kmalloc failure.

Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agodrm/radeon: hold reference to fences in radeon_sa_bo_new
Nicolai Hähnle [Fri, 5 Feb 2016 19:35:53 +0000 (14:35 -0500)]
drm/radeon: hold reference to fences in radeon_sa_bo_new

[ Upstream commit f6ff4f67cdf8455d0a4226eeeaf5af17c37d05eb ]

An arbitrary amount of time can pass between spin_unlock and
radeon_fence_wait_any, so we need to ensure that nobody frees the
fences from under us.

Based on the analogous fix for amdgpu.

Signed-off-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoworkqueue: handle NUMA_NO_NODE for unbound pool_workqueue lookup
Tejun Heo [Wed, 3 Feb 2016 18:54:25 +0000 (13:54 -0500)]
workqueue: handle NUMA_NO_NODE for unbound pool_workqueue lookup

[ Upstream commit d6e022f1d207a161cd88e08ef0371554680ffc46 ]

When looking up the pool_workqueue to use for an unbound workqueue,
workqueue assumes that the target CPU is always bound to a valid NUMA
node.  However, currently, when a CPU goes offline, the mapping is
destroyed and cpu_to_node() returns NUMA_NO_NODE.

This has always been broken but hasn't triggered often enough before
874bbfe600a6 ("workqueue: make sure delayed work run in local cpu").
After the commit, workqueue forcifully assigns the local CPU for
delayed work items without explicit target CPU to fix a different
issue.  This widens the window where CPU can go offline while a
delayed work item is pending causing delayed work items dispatched
with target CPU set to an already offlined CPU.  The resulting
NUMA_NO_NODE mapping makes workqueue try to queue the work item on a
NULL pool_workqueue and thus crash.

While 874bbfe600a6 has been reverted for a different reason making the
bug less visible again, it can still happen.  Fix it by mapping
NUMA_NO_NODE to the default pool_workqueue from unbound_pwq_by_node().
This is a temporary workaround.  The long term solution is keeping CPU
-> NODE mapping stable across CPU off/online cycles which is being
worked on.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Len Brown <len.brown@intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/g/1454424264.11183.46.camel@gmail.com
Link: http://lkml.kernel.org/g/1453702100-2597-1-git-send-email-tangchen@cn.fujitsu.com
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoworkqueue: wq_pool_mutex protects the attrs-installation
Lai Jiangshan [Tue, 12 May 2015 12:32:29 +0000 (20:32 +0800)]
workqueue: wq_pool_mutex protects the attrs-installation

[ Upstream commit 5b95e1af8d17d85a17728f6de7dbff538e6e3c49 ]

Current wq_pool_mutex doesn't proctect the attrs-installation, it results
that ->unbound_attrs, ->numa_pwq_tbl[] and ->dfl_pwq can only be accessed
under wq->mutex and causes some inconveniences. Example, wq_update_unbound_numa()
has to acquire wq->mutex before fetching the wq->unbound_attrs->no_numa
and the old_pwq.

attrs-installation is a short operation, so this change will no cause any
latency for other operations which also acquire the wq_pool_mutex.

The only unprotected attrs-installation code is in apply_workqueue_attrs(),
so this patch touches code less than comments.

It is also a preparation patch for next several patches which read
wq->unbound_attrs, wq->numa_pwq_tbl[] and wq->dfl_pwq with
only wq_pool_mutex held.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoworkqueue: split apply_workqueue_attrs() into 3 stages
Lai Jiangshan [Mon, 27 Apr 2015 09:58:38 +0000 (17:58 +0800)]
workqueue: split apply_workqueue_attrs() into 3 stages

[ Upstream commit 2d5f0764b5264d2954ba6e3deb04f4f5de8e4476 ]

Current apply_workqueue_attrs() includes pwqs-allocation and pwqs-installation,
so when we batch multiple apply_workqueue_attrs()s as a transaction, we can't
ensure the transaction must succeed or fail as a complete unit.

To solve this, we split apply_workqueue_attrs() into three stages.
The first stage does the preparation: allocation memory, pwqs.
The second stage does the attrs-installaion and pwqs-installation.
The third stage frees the allocated memory and (old or unused) pwqs.

As the result, batching multiple apply_workqueue_attrs()s can
succeed or fail as a complete unit:
1) batch do all the first stage for all the workqueues
2) only commit all when all the above succeed.

This patch is a preparation for the next patch ("Allow modifying low level
unbound workqueue cpumask") which will do a multiple apply_workqueue_attrs().

The patch doesn't have functionality changed except two minor adjustment:
1) free_unbound_pwq() for the error path is removed, we use the
   heavier version put_pwq_unlocked() instead since the error path
   is rare. this adjustment simplifies the code.
2) the memory-allocation is also moved into wq_pool_mutex.
   this is needed to avoid to do the further splitting.

tj: minor updates to comments.

Suggested-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mike Galbraith <bitbucket@online.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoahci: Intel DNV device IDs SATA
Alexandra Yates [Fri, 5 Feb 2016 23:27:49 +0000 (15:27 -0800)]
ahci: Intel DNV device IDs SATA

[ Upstream commit 342decff2b846b46fa61eb5ee40986fab79a9a32 ]

Adding Intel codename DNV platform device IDs for SATA.

Signed-off-by: Alexandra Yates <alexandra.yates@linux.intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agophy: twl4030-usb: Fix unbalanced pm_runtime_enable on module reload
Tony Lindgren [Tue, 1 Dec 2015 05:39:54 +0000 (21:39 -0800)]
phy: twl4030-usb: Fix unbalanced pm_runtime_enable on module reload

[ Upstream commit 58a66dba1beac2121d931cda4682ae4d40816af5 ]

If we reload phy-twl4030-usb, we get a warning about unbalanced
pm_runtime_enable. Let's fix the issue and also fix idling of the
device on unload before we attempt to shut it down.

If we don't properly idle the PHY before shutting it down on removal,
the twl4030 ends up consuming about 62mW of extra power compared to
running idle with the module loaded.

Cc: stable@vger.kernel.org
Cc: Bin Liu <b-liu@ti.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: NeilBrown <neil@brown.name>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agophy: twl4030-usb: Relase usb phy on unload
Tony Lindgren [Tue, 1 Dec 2015 05:39:53 +0000 (21:39 -0800)]
phy: twl4030-usb: Relase usb phy on unload

[ Upstream commit b241d31ef2f6a289d33dcaa004714b26e06f476f ]

Otherwise rmmod omap2430; rmmod phy-twl4030-usb; modprobe omap2430
will try to use a non-existing phy and oops:

Unable to handle kernel paging request at virtual address b6f7c1f0
...
[<c048a284>] (devm_usb_get_phy_by_node) from [<bf0758ac>]
(omap2430_musb_init+0x44/0x2b4 [omap2430])
[<bf0758ac>] (omap2430_musb_init [omap2430]) from [<bf055ec0>]
(musb_init_controller+0x194/0x878 [musb_hdrc])

Cc: stable@vger.kernel.org
Cc: Bin Liu <b-liu@ti.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: NeilBrown <neil@brown.name>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agophy: core: fix wrong err handle for phy_power_on
Shawn Lin [Thu, 28 Jan 2016 08:14:18 +0000 (16:14 +0800)]
phy: core: fix wrong err handle for phy_power_on

[ Upstream commit b82fcabe212a11698fd4b3e604d2f81d929d22f6 ]

If phy_pm_runtime_get_sync failed but we already
enable regulator, current code return directly without
doing regulator_disable. This patch fix this problem
and cleanup err handle of phy_power_on to be more readable.

Fixes: 3be88125d85d ("phy: core: Support regulator ...")
Cc: <stable@vger.kernel.org> # v3.18+
Cc: Roger Quadros <rogerq@ti.com>
Cc: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoRevert "workqueue: make sure delayed work run in local cpu"
Tejun Heo [Tue, 9 Feb 2016 21:11:26 +0000 (16:11 -0500)]
Revert "workqueue: make sure delayed work run in local cpu"

[ Upstream commit 041bd12e272c53a35c54c13875839bcb98c999ce ]

This reverts commit 874bbfe600a660cba9c776b3957b1ce393151b76.

Workqueue used to implicity guarantee that work items queued without
explicit CPU specified are put on the local CPU.  Recent changes in
timer broke the guarantee and led to vmstat breakage which was fixed
by 176bed1de5bf ("vmstat: explicitly schedule per-cpu work on the CPU
we need it to run on").

vmstat is the most likely to expose the issue and it's quite possible
that there are other similar problems which are a lot more difficult
to trigger.  As a preventive measure, 874bbfe600a6 ("workqueue: make
sure delayed work run in local cpu") was applied to restore the local
CPU guarnatee.  Unfortunately, the change exposed a bug in timer code
which got fixed by 22b886dd1018 ("timers: Use proper base migration in
add_timer_on()").  Due to code restructuring, the commit couldn't be
backported beyond certain point and stable kernels which only had
874bbfe600a6 started crashing.

The local CPU guarantee was accidental more than anything else and we
want to get rid of it anyway.  As, with the vmstat case fixed,
874bbfe600a6 is causing more problems than it's fixing, it has been
decided to take the chance and officially break the guarantee by
reverting the commit.  A debug feature will be added to force foreign
CPU assignment to expose cases relying on the guarantee and fixes for
the individual cases will be backported to stable as necessary.

Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 874bbfe600a6 ("workqueue: make sure delayed work run in local cpu")
Link: http://lkml.kernel.org/g/20160120211926.GJ10810@quack.suse.cz
Cc: stable@vger.kernel.org
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Daniel Bilik <daniel.bilik@neosystem.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Shaohua Li <shli@fb.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Bilik <daniel.bilik@neosystem.cz>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: timer: Fix race at concurrent reads
Takashi Iwai [Mon, 8 Feb 2016 16:26:58 +0000 (17:26 +0100)]
ALSA: timer: Fix race at concurrent reads

[ Upstream commit 4dff5c7b7093b19c19d3a100f8a3ad87cb7cd9e7 ]

snd_timer_user_read() has a potential race among parallel reads, as
qhead and qused are updated outside the critical section due to
copy_to_user() calls.  Move them into the critical section, and also
sanitize the relevant code a bit.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: hda - Fix bad dereference of jack object
Takashi Iwai [Tue, 9 Feb 2016 09:23:52 +0000 (10:23 +0100)]
ALSA: hda - Fix bad dereference of jack object

[ Upstream commit 2ebab40eb74a0225d5dfba72bfae317dd948fa2d ]

The hda_jack_tbl entries are managed by snd_array for allowing
multiple jacks.  It's good per se, but the problem is that struct
hda_jack_callback keeps the hda_jack_tbl pointer.  Since snd_array
doesn't preserve each pointer at resizing the array, we can't keep the
original pointer but have to deduce the pointer at each time via
snd_array_entry() instead.  Actually, this resulted in the deference
to the wrong pointer on codecs that have many pins such as CS4208.

This patch replaces the pointer to the NID value as the search key.
As an unexpected good side effect, this even simplifies the code, as
only NID is needed in most cases.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: timer: Fix race between stop and interrupt
Takashi Iwai [Tue, 9 Feb 2016 11:02:32 +0000 (12:02 +0100)]
ALSA: timer: Fix race between stop and interrupt

[ Upstream commit ed8b1d6d2c741ab26d60d499d7fbb7ac801f0f51 ]

A slave timer element also unlinks at snd_timer_stop() but it takes
only slave_active_lock.  When a slave is assigned to a master,
however, this may become a race against the master's interrupt
handling, eventually resulting in a list corruption.  The actual bug
could be seen with a syzkaller fuzzer test case in BugLink below.

As a fix, we need to take timeri->timer->lock when timer isn't NULL,
i.e. assigned to a master, while the assignment to a master itself is
protected by slave_active_lock.

BugLink: http://lkml.kernel.org/r/CACT4Y+Y_Bm+7epAb=8Wi=AaWd+DYS7qawX52qxdCfOfY49vozQ@mail.gmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoARM: 8517/1: ICST: avoid arithmetic overflow in icst_hz()
Linus Walleij [Mon, 8 Feb 2016 08:14:37 +0000 (09:14 +0100)]
ARM: 8517/1: ICST: avoid arithmetic overflow in icst_hz()

[ Upstream commit 5070fb14a0154f075c8b418e5bc58a620ae85a45 ]

When trying to set the ICST 307 clock to 25174000 Hz I ran into
this arithmetic error: the icst_hz_to_vco() correctly figure out
DIVIDE=2, RDW=100 and VDW=99 yielding a frequency of
25174000 Hz out of the VCO. (I replicated the icst_hz() function
in a spreadsheet to verify this.)

However, when I called icst_hz() on these VCO settings it would
instead return 4122709 Hz. This causes an error in the common
clock driver for ICST as the common clock framework will call
.round_rate() on the clock which will utilize icst_hz_to_vco()
followed by icst_hz() suggesting the erroneous frequency, and
then the clock gets set to this.

The error did not manifest in the old clock framework since
this high frequency was only used by the CLCD, which calls
clk_set_rate() without first calling clk_round_rate() and since
the old clock framework would not call clk_round_rate() before
setting the frequency, the correct values propagated into
the VCO.

After some experimenting I figured out that it was due to a simple
arithmetic overflow: the divisor for 24Mhz reference frequency
as reference becomes 24000000*2*(99+8)=0x132212400 and the "1"
in bit 32 overflows and is lost.

But introducing an explicit 64-by-32 bit do_div() and casting
the divisor into (u64) we get the right frequency back, and the
right frequency gets set.

Tested on the ARM Versatile.

Cc: stable@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: timer: Fix wrong instance passed to slave callbacks
Takashi Iwai [Mon, 8 Feb 2016 16:36:25 +0000 (17:36 +0100)]
ALSA: timer: Fix wrong instance passed to slave callbacks

[ Upstream commit 117159f0b9d392fb433a7871426fad50317f06f7 ]

In snd_timer_notify1(), the wrong timer instance was passed for slave
ccallback function.  This leads to the access to the wrong data when
an incompatible master is handled (e.g. the master is the sequencer
timer and the slave is a user timer), as spotted by syzkaller fuzzer.

This patch fixes that wrong assignment.

BugLink: http://lkml.kernel.org/r/CACT4Y+Y_Bm+7epAb=8Wi=AaWd+DYS7qawX52qxdCfOfY49vozQ@mail.gmail.com
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agodrm/i915/dsi: don't pass arbitrary data to sideband
Jani Nikula [Thu, 4 Feb 2016 10:50:50 +0000 (12:50 +0200)]
drm/i915/dsi: don't pass arbitrary data to sideband

[ Upstream commit 26f6f2d301c1fb46acb1138ee155125815239b0d ]

Since sequence block v2 the second byte contains flags other than just
pull up/down. Don't pass arbitrary data to the sideband interface.

The rest may or may not work for sequence block v2, but there should be
no harm done.

Cc: stable@vger.kernel.org
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/ebe3c2eee623afc4b3a134533b01f8d591d13f32.1454582914.git.jani.nikula@intel.com
(cherry picked from commit 4e1c63e3761b84ec7d87c75b58bbc8bcf18e98ee)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agodrm/i915/dsi: defend gpio table against out of bounds access
Jani Nikula [Thu, 4 Feb 2016 10:50:49 +0000 (12:50 +0200)]
drm/i915/dsi: defend gpio table against out of bounds access

[ Upstream commit 4db3a2448ec8902310acb78de39b6227a9a56ac8 ]

Do not blindly trust the VBT data used for indexing.

Cc: stable@vger.kernel.org
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/cc32d40c2b47f2d2151811855ac2c3dabab1d57d.1454582914.git.jani.nikula@intel.com
(cherry picked from commit 5d2d0a12d3d08bf50434f0b5947bb73bac04b941)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: dummy: Implement timer backend switching more safely
Takashi Iwai [Tue, 2 Feb 2016 14:27:36 +0000 (15:27 +0100)]
ALSA: dummy: Implement timer backend switching more safely

[ Upstream commit ddce57a6f0a2d8d1bfacfa77f06043bc760403c2 ]

Currently the selected timer backend is referred at any moment from
the running PCM callbacks.  When the backend is switched, it's
possible to lead to inconsistency from the running backend.  This was
pointed by syzkaller fuzzer, and the commit [7ee96216c31a: ALSA:
dummy: Disable switching timer backend via sysfs] disabled the dynamic
switching for avoiding the crash.

This patch improves the handling of timer backend switching.  It keeps
the reference to the selected backend during the whole operation of an
opened stream so that it won't be changed by other streams.

Together with this change, the hrtimer parameter is reenabled as
writable now.

NOTE: this patch also turned out to fix the still remaining race.
Namely, ops was still replaced dynamically at dummy_pcm_open:

  static int dummy_pcm_open(struct snd_pcm_substream *substream)
  {
  ....
          dummy->timer_ops = &dummy_systimer_ops;
          if (hrtimer)
                  dummy->timer_ops = &dummy_hrtimer_ops;

Since dummy->timer_ops is common among all streams, and when the
replacement happens during accesses of other streams, it may lead to a
crash.  This was actually triggered by syzkaller fuzzer and KASAN.

This patch rewrites the code not to use the ops shared by all streams
any longer, too.

BugLink: http://lkml.kernel.org/r/CACT4Y+aZ+xisrpuM6cOXbL21DuM0yVxPYXf4cD4Md9uw0C3dBQ@mail.gmail.com
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoklist: fix starting point removed bug in klist iterators
James Bottomley [Wed, 13 Jan 2016 16:10:31 +0000 (08:10 -0800)]
klist: fix starting point removed bug in klist iterators

[ Upstream commit 00cd29b799e3449f0c68b1cc77cd4a5f95b42d17 ]

The starting node for a klist iteration is often passed in from
somewhere way above the klist infrastructure, meaning there's no
guarantee the node is still on the list.  We've seen this in SCSI where
we use bus_find_device() to iterate through a list of devices.  In the
face of heavy hotplug activity, the last device returned by
bus_find_device() can be removed before the next call.  This leads to

Dec  3 13:22:02 localhost kernel: WARNING: CPU: 2 PID: 28073 at include/linux/kref.h:47 klist_iter_init_node+0x3d/0x50()
Dec  3 13:22:02 localhost kernel: Modules linked in: scsi_debug x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel joydev iTCO_wdt dcdbas ipmi_devintf acpi_power_meter iTCO_vendor_support ipmi_si imsghandler pcspkr wmi acpi_cpufreq tpm_tis tpm shpchp lpc_ich mfd_core nfsd nfs_acl lockd grace sunrpc tg3 ptp pps_core
Dec  3 13:22:02 localhost kernel: CPU: 2 PID: 28073 Comm: cat Not tainted 4.4.0-rc1+ #2
Dec  3 13:22:02 localhost kernel: Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013
Dec  3 13:22:02 localhost kernel: ffffffff81a20e77 ffff880613acfd18 ffffffff81321eef 0000000000000000
Dec  3 13:22:02 localhost kernel: ffff880613acfd50 ffffffff8107ca52 ffff88061176b198 0000000000000000
Dec  3 13:22:02 localhost kernel: ffffffff814542b0 ffff880610cfb100 ffff88061176b198 ffff880613acfd60
Dec  3 13:22:02 localhost kernel: Call Trace:
Dec  3 13:22:02 localhost kernel: [<ffffffff81321eef>] dump_stack+0x44/0x55
Dec  3 13:22:02 localhost kernel: [<ffffffff8107ca52>] warn_slowpath_common+0x82/0xc0
Dec  3 13:22:02 localhost kernel: [<ffffffff814542b0>] ? proc_scsi_show+0x20/0x20
Dec  3 13:22:02 localhost kernel: [<ffffffff8107cb4a>] warn_slowpath_null+0x1a/0x20
Dec  3 13:22:02 localhost kernel: [<ffffffff8167225d>] klist_iter_init_node+0x3d/0x50
Dec  3 13:22:02 localhost kernel: [<ffffffff81421d41>] bus_find_device+0x51/0xb0
Dec  3 13:22:02 localhost kernel: [<ffffffff814545ad>] scsi_seq_next+0x2d/0x40
[...]

And an eventual crash. It can actually occur in any hotplug system
which has a device finder and a starting device.

We can fix this globally by making sure the starting node for
klist_iter_init_node() is actually a member of the list before using it
(and by starting from the beginning if it isn't).

Reported-by: Ewan D. Milne <emilne@redhat.com>
Tested-by: Ewan D. Milne <emilne@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: hda - Fix speaker output from VAIO AiO machines
Takashi Iwai [Sun, 7 Feb 2016 08:38:26 +0000 (09:38 +0100)]
ALSA: hda - Fix speaker output from VAIO AiO machines

[ Upstream commit c44d9b1181cf34e0860c72cc8a00e0c47417aac0 ]

Some Sony VAIO AiO models (VGC-JS4EF and VGC-JS25G, both with PCI SSID
104d:9044) need the same quirk to make the speaker working properly.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112031
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agopty: make sure super_block is still valid in final /dev/tty close
Herton R. Krzesinski [Thu, 14 Jan 2016 19:56:58 +0000 (17:56 -0200)]
pty: make sure super_block is still valid in final /dev/tty close

[ Upstream commit 1f55c718c290616889c04946864a13ef30f64929 ]

Considering current pty code and multiple devpts instances, it's possible
to umount a devpts file system while a program still has /dev/tty opened
pointing to a previosuly closed pty pair in that instance. In the case all
ptmx and pts/N files are closed, umount can be done. If the program closes
/dev/tty after umount is done, devpts_kill_index will use now an invalid
super_block, which was already destroyed in the umount operation after
running ->kill_sb. This is another "use after free" type of issue, but now
related to the allocated super_block instance.

To avoid the problem (warning at ida_remove and potential crashes) for
this specific case, I added two functions in devpts which grabs additional
references to the super_block, which pty code now uses so it makes sure
the super block structure is still valid until pty shutdown is done.
I also moved the additional inode references to the same functions, which
also covered similar case with inode being freed before /dev/tty final
close/shutdown.

Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Cc: stable@vger.kernel.org # 2.6.29+
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agopty: fix possible use after free of tty->driver_data
Herton R. Krzesinski [Mon, 11 Jan 2016 14:07:43 +0000 (12:07 -0200)]
pty: fix possible use after free of tty->driver_data

[ Upstream commit 2831c89f42dcde440cfdccb9fee9f42d54bbc1ef ]

This change fixes a bug for a corner case where we have the the last
release from a pty master/slave coming from a previously opened /dev/tty
file. When this happens, the tty->driver_data can be stale, due to all
ptmx or pts/N files having already been closed before (and thus the inode
related to these files, which tty->driver_data points to, being already
freed/destroyed).

The fix here is to keep a reference on the opened master ptmx inode.
We maintain the inode referenced until the final pty_unix98_shutdown,
and only pass this inode to devpts_kill_index.

Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Cc: <stable@vger.kernel.org> # 2.6.29+
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agotty: Add support for PCIe WCH382 2S multi-IO card
Jeremy McNicoll [Tue, 2 Feb 2016 21:00:45 +0000 (13:00 -0800)]
tty: Add support for PCIe WCH382 2S multi-IO card

[ Upstream commit 7dde55787b43a8f2b4021916db38d90c03a2ec64 ]

WCH382 2S board is a PCIe card with 2 DB9 COM ports detected as
Serial controller: Device 1c00:3253 (rev 10) (prog-if 05 [16850])

Signed-off-by: Jeremy McNicoll <jmcnicol@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoserial: omap: Prevent DoS using unprivileged ioctl(TIOCSRS485)
Peter Hurley [Tue, 12 Jan 2016 23:14:46 +0000 (15:14 -0800)]
serial: omap: Prevent DoS using unprivileged ioctl(TIOCSRS485)

[ Upstream commit 308bbc9ab838d0ace0298268c7970ba9513e2c65 ]

The omap-serial driver emulates RS485 delays using software timers,
but neglects to clamp the input values from the unprivileged
ioctl(TIOCSRS485). Because the software implementation busy-waits,
malicious userspace could stall the cpu for ~49 days.

Clamp the input values to < 100ms.

Fixes: 4a0ac0f55b18 ("OMAP: add RS485 support")
Cc: <stable@vger.kernel.org> # 3.12+
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoqla2xxx: Use pci_enable_msix_range() instead of pci_enable_msix()
Quinn Tran [Thu, 4 Feb 2016 16:45:16 +0000 (11:45 -0500)]
qla2xxx: Use pci_enable_msix_range() instead of pci_enable_msix()

[ Upstream commit 84e32a06f4f8756ce9ec3c8dc7e97896575f0771 ]

As result of deprecation of MSI-X/MSI enablement functions
pci_enable_msix() and pci_enable_msi_block() all drivers
using these two interfaces need to be updated to use the
new pci_enable_msi_range()  or pci_enable_msi_exact()
and pci_enable_msix_range() or pci_enable_msix_exact()
interfaces.

Log message code 0x00c6 preserved, although it is reported
after successful call to pci_enable_msix_range(), not before
possibly unsuccessful call to pci_enable_msix(). Consumers
of the error code should not notice the difference.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Acked-by: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: qla2xxx-upstream@qlogic.com
Cc: linux-scsi@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agocrypto: atmel-sha - remove calls of clk_prepare() from atomic contexts
Cyrille Pitchen [Fri, 5 Feb 2016 12:45:13 +0000 (13:45 +0100)]
crypto: atmel-sha - remove calls of clk_prepare() from atomic contexts

[ Upstream commit ee36c87a655325a7b5e442a9650a782db4ea20d2 ]

commit c033042aa8f69894df37dabcaa0231594834a4e4 upstream.

clk_prepare()/clk_unprepare() must not be called within atomic context.

This patch calls clk_prepare() once for all from atmel_sha_probe() and
clk_unprepare() from atmel_sha_remove().

Then calls of clk_prepare_enable()/clk_disable_unprepare() were replaced
by calls of clk_enable()/clk_disable().

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Reported-by: Matthias Mayr <matthias.mayr@student.kit.edu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agocrypto: atmel - Check for clk_prepare_enable() return value
LABBE Corentin [Fri, 2 Oct 2015 12:12:58 +0000 (14:12 +0200)]
crypto: atmel - Check for clk_prepare_enable() return value

[ Upstream commit 9d83d299549d0e121245d56954242750d0c14338 ]

clk_prepare_enable() can fail so add a check for this and
return the error code if it fails.

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agocrypto: atmel - use devm_xxx() managed function
LABBE Corentin [Mon, 12 Oct 2015 17:47:03 +0000 (19:47 +0200)]
crypto: atmel - use devm_xxx() managed function

[ Upstream commit b0e8b3417a620e6e0a91fd526fbc6db78714198e ]

Using the devm_xxx() managed function to stripdown the error and remove
code.

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoBackport fix for crypto: algif_skcipher - Fix race condition in skcipher_check_key
Herbert Xu [Fri, 26 Feb 2016 11:44:11 +0000 (12:44 +0100)]
Backport fix for crypto: algif_skcipher - Fix race condition in skcipher_check_key

commit 1822793a523e5d5730b19cc21160ff1717421bc8 upstream.

We need to lock the child socket in skcipher_check_key as otherwise
two simultaneous calls can cause the parent socket to be freed.

Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoBackport fix for crypto: algif_skcipher - Remove custom release parent function
Herbert Xu [Fri, 26 Feb 2016 11:44:10 +0000 (12:44 +0100)]
Backport fix for crypto: algif_skcipher - Remove custom release parent function

commit d7b65aee1e7b4c87922b0232eaba56a8a143a4a0 upstream.

This patch removes the custom release parent function as the
generic af_alg_release_parent now works for nokey sockets too.

Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoBackport fix for crypto: algif_skcipher - Add nokey compatibility path
Herbert Xu [Fri, 26 Feb 2016 11:44:09 +0000 (12:44 +0100)]
Backport fix for crypto: algif_skcipher - Add nokey compatibility path

commit a0fa2d037129a9849918a92d91b79ed6c7bd2818 upstream.

This patch adds a compatibility path to support old applications
that do acept(2) before setkey.

Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoBackport fix for crypto: algif_skcipher - Require setkey before accept(2)
Herbert Xu [Fri, 26 Feb 2016 11:44:08 +0000 (12:44 +0100)]
Backport fix for crypto: algif_skcipher - Require setkey before accept(2)

commit dd504589577d8e8e70f51f997ad487a4cb6c026f upstream.

Some cipher implementations will crash if you try to use them
without calling setkey first.  This patch adds a check so that
the accept(2) call will fail with -ENOKEY if setkey hasn't been
done on the socket yet.

Cc: stable@vger.kernel.org
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
[backported to 4.1 by Milan Broz <gmazyland@gmail.com>]

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agocrypto: user - lock crypto_alg_list on alg dump
Mathias Krause [Mon, 1 Feb 2016 13:27:30 +0000 (14:27 +0100)]
crypto: user - lock crypto_alg_list on alg dump

[ Upstream commit 63e41ebc6630f39422d87f8a4bade1e793f37a01 ]

We miss to take the crypto_alg_sem semaphore when traversing the
crypto_alg_list for CRYPTO_MSG_GETALG dumps. This allows a race with
crypto_unregister_alg() removing algorithms from the list while we're
still traversing it, thereby leading to a use-after-free as show below:

[ 3482.071639] general protection fault: 0000 [#1] SMP
[ 3482.075639] Modules linked in: aes_x86_64 glue_helper lrw ablk_helper cryptd gf128mul ipv6 pcspkr serio_raw virtio_net microcode virtio_pci virtio_ring virtio sr_mod cdrom [last unloaded: aesni_intel]
[ 3482.075639] CPU: 1 PID: 11065 Comm: crconf Not tainted 4.3.4-grsec+ #126
[ 3482.075639] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 3482.075639] task: ffff88001cd41a40 ti: ffff88001cd422c8 task.ti: ffff88001cd422c8
[ 3482.075639] RIP: 0010:[<ffffffff93722bd3>]  [<ffffffff93722bd3>] strncpy+0x13/0x30
[ 3482.075639] RSP: 0018:ffff88001f713b60  EFLAGS: 00010202
[ 3482.075639] RAX: ffff88001f6c4430 RBX: ffff88001f6c43a0 RCX: ffff88001f6c4430
[ 3482.075639] RDX: 0000000000000040 RSI: fefefefefefeff16 RDI: ffff88001f6c4430
[ 3482.075639] RBP: ffff88001f713b60 R08: ffff88001f6c4470 R09: ffff88001f6c4480
[ 3482.075639] R10: 0000000000000002 R11: 0000000000000246 R12: ffff88001ce2aa28
[ 3482.075639] R13: ffff880000093700 R14: ffff88001f5e4bf8 R15: 0000000000003b20
[ 3482.075639] FS:  0000033826fa2700(0000) GS:ffff88001e900000(0000) knlGS:0000000000000000
[ 3482.075639] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3482.075639] CR2: ffffffffff600400 CR3: 00000000139ec000 CR4: 00000000001606f0
[ 3482.075639] Stack:
[ 3482.075639]  ffff88001f713bd8 ffffffff936ccd00 ffff88001e5c4200 ffff880000093700
[ 3482.075639]  ffff88001f713bd0 ffffffff938ef4bf 0000000000000000 0000000000003b20
[ 3482.075639]  ffff88001f5e4bf8 ffff88001f5e4848 0000000000000000 0000000000003b20
[ 3482.075639] Call Trace:
[ 3482.075639]  [<ffffffff936ccd00>] crypto_report_alg+0xc0/0x3e0
[ 3482.075639]  [<ffffffff938ef4bf>] ? __alloc_skb+0x16f/0x300
[ 3482.075639]  [<ffffffff936cd08a>] crypto_dump_report+0x6a/0x90
[ 3482.075639]  [<ffffffff93935707>] netlink_dump+0x147/0x2e0
[ 3482.075639]  [<ffffffff93935f99>] __netlink_dump_start+0x159/0x190
[ 3482.075639]  [<ffffffff936ccb13>] crypto_user_rcv_msg+0xc3/0x130
[ 3482.075639]  [<ffffffff936cd020>] ? crypto_report_alg+0x3e0/0x3e0
[ 3482.075639]  [<ffffffff936cc4b0>] ? alg_test_crc32c+0x120/0x120
[ 3482.075639]  [<ffffffff93933145>] ? __netlink_lookup+0xd5/0x120
[ 3482.075639]  [<ffffffff936cca50>] ? crypto_add_alg+0x1d0/0x1d0
[ 3482.075639]  [<ffffffff93938141>] netlink_rcv_skb+0xe1/0x130
[ 3482.075639]  [<ffffffff936cc4f8>] crypto_netlink_rcv+0x28/0x40
[ 3482.075639]  [<ffffffff939375a8>] netlink_unicast+0x108/0x180
[ 3482.075639]  [<ffffffff93937c21>] netlink_sendmsg+0x541/0x770
[ 3482.075639]  [<ffffffff938e31e1>] sock_sendmsg+0x21/0x40
[ 3482.075639]  [<ffffffff938e4763>] SyS_sendto+0xf3/0x130
[ 3482.075639]  [<ffffffff93444203>] ? bad_area_nosemaphore+0x13/0x20
[ 3482.075639]  [<ffffffff93444470>] ? __do_page_fault+0x80/0x3a0
[ 3482.075639]  [<ffffffff939d80cb>] entry_SYSCALL_64_fastpath+0x12/0x6e
[ 3482.075639] Code: 88 4a ff 75 ed 5d 48 0f ba 2c 24 3f c3 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 85 d2 48 89 f8 48 89 f9 4c 8d 04 17 48 89 e5 74 15 <0f> b6 16 80 fa 01 88 11 48 83 de ff 48 83 c1 01 4c 39 c1 75 eb
[ 3482.075639] RIP  [<ffffffff93722bd3>] strncpy+0x13/0x30

To trigger the race run the following loops simultaneously for a while:
  $ while : ; do modprobe aesni-intel; rmmod aesni-intel; done
  $ while : ; do crconf show all > /dev/null; done

Fix the race by taking the crypto_alg_sem read lock, thereby preventing
crypto_unregister_alg() from modifying the algorithm list during the
dump.

This bug has been detected by the PaX memory sanitize feature.

Cc: stable@vger.kernel.org
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: PaX Team <pageexec@freemail.hu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoRevert "ALSA: hda - Fix noise on Gigabyte Z170X mobo"
Takashi Iwai [Fri, 5 Feb 2016 19:12:24 +0000 (20:12 +0100)]
Revert "ALSA: hda - Fix noise on Gigabyte Z170X mobo"

[ Upstream commit 6c361d10e0eb859233c71954abcd20d2d8700587 ]

This reverts commit 0c25ad80408e95e0a4fbaf0056950206e95f726f.

The original commit disabled the aamixer path due to the noise
problem, but it turned out that some mobo with the same PCI SSID
doesn't suffer from the issue, and the disabled function (analog
loopback) is still demanded by users.

Since the recent commit [e7fdd52779a6: ALSA: hda - Implement loopback
control switch for Realtek and other codecs], we have the dynamic
mixer switch to enable/disable the aamix path, and we don't have to
disable the path statically any longer.  So, let's revert the
disablement, so that only the user suffering from the noise problem
can turn off the aamix on the fly.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=108301
Reported-by: <mutedbytes@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoALSA: hda - Fix static checker warning in patch_hdmi.c
David Henningsson [Fri, 5 Feb 2016 08:05:41 +0000 (09:05 +0100)]
ALSA: hda - Fix static checker warning in patch_hdmi.c

[ Upstream commit 360a8245680053619205a3ae10e6bfe624a5da1d ]

The static checker warning is:

sound/pci/hda/patch_hdmi.c:460 hdmi_eld_ctl_get()
error: __memcpy() 'eld->eld_buffer' too small (256 vs 512)

I have a hard time figuring out if this can ever cause an information leak
(I don't think so), but nonetheless it does not hurt to increase the
robustness of the code.

Fixes: 68e03de98507 ('ALSA: hda - hdmi: Do not expose eld data when eld is invalid')
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Cc: <stable@vger.kernel.org> # v3.9+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoSCSI: Add Marvell Console to VPD blacklist
Mika Westerberg [Wed, 27 Jan 2016 14:19:13 +0000 (16:19 +0200)]
SCSI: Add Marvell Console to VPD blacklist

[ Upstream commit 82c43310508eb19eb41fe7862e89afeb74030b84 ]

I have a Marvell 88SE9230 SATA Controller that has some sort of
integrated console SCSI device attached to one of the ports.

  ata14: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
  ata14.00: ATAPI: MARVELL VIRTUALL, 1.09, max UDMA/66
  ata14.00: configured for UDMA/66
  scsi 13:0:0:0: Processor         Marvell  Console 1.01 PQ: 0 ANSI: 5

Sending it VPD INQUIRY command seem to always fail with following error:

  ata14.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6
  ata14.00: irq_stat 0x40000001
  ata14.00: cmd a0/01:00:00:00:01/00:00:00:00:00/a0 tag 2 dma 16640 in
            Inquiry 12 01 00 00 ff 00res 00/00:00:00:00:00/00:00:00:00:00/00 Emask 0x3 (HSM violation)
  ata14: hard resetting link

This has been minor annoyance (only error printed on dmesg) until commit
09e2b0b14690 ("scsi: rescan VPD attributes") added call to scsi_attach_vpd()
in scsi_rescan_device(). The commit causes the system to splat out
following errors continuously without ever reaching the UI:

  ata14.00: configured for UDMA/66
  ata14: EH complete
  ata14.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6
  ata14.00: irq_stat 0x40000001
  ata14.00: cmd a0/01:00:00:00:01/00:00:00:00:00/a0 tag 6 dma 16640 in
            Inquiry 12 01 00 00 ff 00res 00/00:00:00:00:00/00:00:00:00:00/00 Emask 0x3 (HSM violation)
  ata14: hard resetting link
  ata14: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
  ata14.00: configured for UDMA/66
  ata14: EH complete
  ata14.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6
  ata14.00: irq_stat 0x40000001
  ata14.00: cmd a0/01:00:00:00:01/00:00:00:00:00/a0 tag 7 dma 16640 in
            Inquiry 12 01 00 00 ff 00res 00/00:00:00:00:00/00:00:00:00:00/00 Emask 0x3 (HSM violation)

Without in-depth understanding of SCSI layer and the Marvell controller,
I suspect this happens because when the link goes down (because of an
error) we schedule scsi_rescan_device() which again fails to read VPD
data... ad infinitum.

Since VPD data cannot be read from the device anyway we prevent the SCSI
layer from even trying by blacklisting the device. This gets away the
error and the system starts up normally.

[mkp: Widened the match to all revisions of this device]

Cc: <stable@vger.kernel.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoscsi_dh_rdac: always retry MODE SELECT on command lock violation
Hannes Reinecke [Fri, 22 Jan 2016 14:42:41 +0000 (15:42 +0100)]
scsi_dh_rdac: always retry MODE SELECT on command lock violation

[ Upstream commit d2d06d4fe0f2cc2df9b17fefec96e6e1a1271d91 ]

If MODE SELECT returns with sense '05/91/36' (command lock violation)
it should always be retried without counting the number of retries.
During an HBA upgrade or similar circumstances one might see a flood
of MODE SELECT command from various HBAs, which will easily trigger
the sense code and exceed the retry count.

Cc: <stable@vger.kernel.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agoBtrfs: fix hang on extent buffer lock caused by the inode_paths ioctl
Filipe Manana [Wed, 3 Feb 2016 19:17:27 +0000 (19:17 +0000)]
Btrfs: fix hang on extent buffer lock caused by the inode_paths ioctl

[ Upstream commit 0c0fe3b0fa45082cd752553fdb3a4b42503a118e ]

While doing some tests I ran into an hang on an extent buffer's rwlock
that produced the following trace:

[39389.800012] NMI watchdog: BUG: soft lockup - CPU#15 stuck for 22s! [fdm-stress:32166]
[39389.800016] NMI watchdog: BUG: soft lockup - CPU#14 stuck for 22s! [fdm-stress:32165]
[39389.800016] Modules linked in: btrfs dm_mod ppdev xor sha256_generic hmac raid6_pq drbg ansi_cprng aesni_intel i2c_piix4 acpi_cpufreq aes_x86_64 ablk_helper tpm_tis parport_pc i2c_core sg cryptd evdev psmouse lrw tpm parport gf128mul serio_raw pcspkr glue_helper processor button loop autofs4 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last unloaded: btrfs]
[39389.800016] irq event stamp: 0
[39389.800016] hardirqs last  enabled at (0): [<          (null)>]           (null)
[39389.800016] hardirqs last disabled at (0): [<ffffffff8104e58d>] copy_process+0x638/0x1a35
[39389.800016] softirqs last  enabled at (0): [<ffffffff8104e58d>] copy_process+0x638/0x1a35
[39389.800016] softirqs last disabled at (0): [<          (null)>]           (null)
[39389.800016] CPU: 14 PID: 32165 Comm: fdm-stress Not tainted 4.4.0-rc6-btrfs-next-18+ #1
[39389.800016] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[39389.800016] task: ffff880175b1ca40 ti: ffff8800a185c000 task.ti: ffff8800a185c000
[39389.800016] RIP: 0010:[<ffffffff810902af>]  [<ffffffff810902af>] queued_spin_lock_slowpath+0x57/0x158
[39389.800016] RSP: 0018:ffff8800a185fb80  EFLAGS: 00000202
[39389.800016] RAX: 0000000000000101 RBX: ffff8801710c4e9c RCX: 0000000000000101
[39389.800016] RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000001
[39389.800016] RBP: ffff8800a185fb98 R08: 0000000000000001 R09: 0000000000000000
[39389.800016] R10: ffff8800a185fb68 R11: 6db6db6db6db6db7 R12: ffff8801710c4e98
[39389.800016] R13: ffff880175b1ca40 R14: ffff8800a185fc10 R15: ffff880175b1ca40
[39389.800016] FS:  00007f6d37fff700(0000) GS:ffff8802be9c0000(0000) knlGS:0000000000000000
[39389.800016] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[39389.800016] CR2: 00007f6d300019b8 CR3: 0000000037c93000 CR4: 00000000001406e0
[39389.800016] Stack:
[39389.800016]  ffff8801710c4e98 ffff8801710c4e98 ffff880175b1ca40 ffff8800a185fbb0
[39389.800016]  ffffffff81091e11 ffff8801710c4e98 ffff8800a185fbc8 ffffffff81091895
[39389.800016]  ffff8801710c4e98 ffff8800a185fbe8 ffffffff81486c5c ffffffffa067288c
[39389.800016] Call Trace:
[39389.800016]  [<ffffffff81091e11>] queued_read_lock_slowpath+0x46/0x60
[39389.800016]  [<ffffffff81091895>] do_raw_read_lock+0x3e/0x41
[39389.800016]  [<ffffffff81486c5c>] _raw_read_lock+0x3d/0x44
[39389.800016]  [<ffffffffa067288c>] ? btrfs_tree_read_lock+0x54/0x125 [btrfs]
[39389.800016]  [<ffffffffa067288c>] btrfs_tree_read_lock+0x54/0x125 [btrfs]
[39389.800016]  [<ffffffffa0622ced>] ? btrfs_find_item+0xa7/0xd2 [btrfs]
[39389.800016]  [<ffffffffa069363f>] btrfs_ref_to_path+0xd6/0x174 [btrfs]
[39389.800016]  [<ffffffffa0693730>] inode_to_path+0x53/0xa2 [btrfs]
[39389.800016]  [<ffffffffa0693e2e>] paths_from_inode+0x117/0x2ec [btrfs]
[39389.800016]  [<ffffffffa0670cff>] btrfs_ioctl+0xd5b/0x2793 [btrfs]
[39389.800016]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[39389.800016]  [<ffffffff81276727>] ? __this_cpu_preempt_check+0x13/0x15
[39389.800016]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[39389.800016]  [<ffffffff8118b3d4>] ? rcu_read_unlock+0x3e/0x5d
[39389.800016]  [<ffffffff811822f8>] do_vfs_ioctl+0x42b/0x4ea
[39389.800016]  [<ffffffff8118b4f3>] ? __fget_light+0x62/0x71
[39389.800016]  [<ffffffff8118240e>] SyS_ioctl+0x57/0x79
[39389.800016]  [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[39389.800016] Code: b9 01 01 00 00 f7 c6 00 ff ff ff 75 32 83 fe 01 89 ca 89 f0 0f 45 d7 f0 0f b1 13 39 f0 74 04 89 c6 eb e2 ff ca 0f 84 fa 00 00 00 <8b> 03 84 c0 74 04 f3 90 eb f6 66 c7 03 01 00 e9 e6 00 00 00 e8
[39389.800012] Modules linked in: btrfs dm_mod ppdev xor sha256_generic hmac raid6_pq drbg ansi_cprng aesni_intel i2c_piix4 acpi_cpufreq aes_x86_64 ablk_helper tpm_tis parport_pc i2c_core sg cryptd evdev psmouse lrw tpm parport gf128mul serio_raw pcspkr glue_helper processor button loop autofs4 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last unloaded: btrfs]
[39389.800012] irq event stamp: 0
[39389.800012] hardirqs last  enabled at (0): [<          (null)>]           (null)
[39389.800012] hardirqs last disabled at (0): [<ffffffff8104e58d>] copy_process+0x638/0x1a35
[39389.800012] softirqs last  enabled at (0): [<ffffffff8104e58d>] copy_process+0x638/0x1a35
[39389.800012] softirqs last disabled at (0): [<          (null)>]           (null)
[39389.800012] CPU: 15 PID: 32166 Comm: fdm-stress Tainted: G             L  4.4.0-rc6-btrfs-next-18+ #1
[39389.800012] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[39389.800012] task: ffff880179294380 ti: ffff880034a60000 task.ti: ffff880034a60000
[39389.800012] RIP: 0010:[<ffffffff81091e8d>]  [<ffffffff81091e8d>] queued_write_lock_slowpath+0x62/0x72
[39389.800012] RSP: 0018:ffff880034a639f0  EFLAGS: 00000206
[39389.800012] RAX: 0000000000000101 RBX: ffff8801710c4e98 RCX: 0000000000000000
[39389.800012] RDX: 00000000000000ff RSI: 0000000000000000 RDI: ffff8801710c4e9c
[39389.800012] RBP: ffff880034a639f8 R08: 0000000000000001 R09: 0000000000000000
[39389.800012] R10: ffff880034a639b0 R11: 0000000000001000 R12: ffff8801710c4e98
[39389.800012] R13: 0000000000000001 R14: ffff880172cbc000 R15: ffff8801710c4e00
[39389.800012] FS:  00007f6d377fe700(0000) GS:ffff8802be9e0000(0000) knlGS:0000000000000000
[39389.800012] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[39389.800012] CR2: 00007f6d3d3c1000 CR3: 0000000037c93000 CR4: 00000000001406e0
[39389.800012] Stack:
[39389.800012]  ffff8801710c4e98 ffff880034a63a10 ffffffff81091963 ffff8801710c4e98
[39389.800012]  ffff880034a63a30 ffffffff81486f1b ffffffffa0672cb3 ffff8801710c4e00
[39389.800012]  ffff880034a63a78 ffffffffa0672cb3 ffff8801710c4e00 ffff880034a63a58
[39389.800012] Call Trace:
[39389.800012]  [<ffffffff81091963>] do_raw_write_lock+0x72/0x8c
[39389.800012]  [<ffffffff81486f1b>] _raw_write_lock+0x3a/0x41
[39389.800012]  [<ffffffffa0672cb3>] ? btrfs_tree_lock+0x119/0x251 [btrfs]
[39389.800012]  [<ffffffffa0672cb3>] btrfs_tree_lock+0x119/0x251 [btrfs]
[39389.800012]  [<ffffffffa061aeba>] ? rcu_read_unlock+0x5b/0x5d [btrfs]
[39389.800012]  [<ffffffffa061ce13>] ? btrfs_root_node+0xda/0xe6 [btrfs]
[39389.800012]  [<ffffffffa061ce83>] btrfs_lock_root_node+0x22/0x42 [btrfs]
[39389.800012]  [<ffffffffa062046b>] btrfs_search_slot+0x1b8/0x758 [btrfs]
[39389.800012]  [<ffffffff810fc6b0>] ? time_hardirqs_on+0x15/0x28
[39389.800012]  [<ffffffffa06365db>] btrfs_lookup_inode+0x31/0x95 [btrfs]
[39389.800012]  [<ffffffff8108d62f>] ? trace_hardirqs_on+0xd/0xf
[39389.800012]  [<ffffffff8148482b>] ? mutex_lock_nested+0x397/0x3bc
[39389.800012]  [<ffffffffa068821b>] __btrfs_update_delayed_inode+0x59/0x1c0 [btrfs]
[39389.800012]  [<ffffffffa068858e>] __btrfs_commit_inode_delayed_items+0x194/0x5aa [btrfs]
[39389.800012]  [<ffffffff81486ab7>] ? _raw_spin_unlock+0x31/0x44
[39389.800012]  [<ffffffffa0688a48>] __btrfs_run_delayed_items+0xa4/0x15c [btrfs]
[39389.800012]  [<ffffffffa0688d62>] btrfs_run_delayed_items+0x11/0x13 [btrfs]
[39389.800012]  [<ffffffffa064048e>] btrfs_commit_transaction+0x234/0x96e [btrfs]
[39389.800012]  [<ffffffffa0618d10>] btrfs_sync_fs+0x145/0x1ad [btrfs]
[39389.800012]  [<ffffffffa0671176>] btrfs_ioctl+0x11d2/0x2793 [btrfs]
[39389.800012]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[39389.800012]  [<ffffffff81140261>] ? __might_fault+0x4c/0xa7
[39389.800012]  [<ffffffff81140261>] ? __might_fault+0x4c/0xa7
[39389.800012]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[39389.800012]  [<ffffffff8118b3d4>] ? rcu_read_unlock+0x3e/0x5d
[39389.800012]  [<ffffffff811822f8>] do_vfs_ioctl+0x42b/0x4ea
[39389.800012]  [<ffffffff8118b4f3>] ? __fget_light+0x62/0x71
[39389.800012]  [<ffffffff8118240e>] SyS_ioctl+0x57/0x79
[39389.800012]  [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[39389.800012] Code: f0 0f b1 13 85 c0 75 ef eb 2a f3 90 8a 03 84 c0 75 f8 f0 0f b0 13 84 c0 75 f0 ba ff 00 00 00 eb 0a f0 0f b1 13 ff c8 74 0b f3 90 <8b> 03 83 f8 01 75 f7 eb ed c6 43 04 00 5b 5d c3 0f 1f 44 00 00

This happens because in the code path executed by the inode_paths ioctl we
end up nesting two calls to read lock a leaf's rwlock when after the first
call to read_lock() and before the second call to read_lock(), another
task (running the delayed items as part of a transaction commit) has
already called write_lock() against the leaf's rwlock. This situation is
illustrated by the following diagram:

         Task A                       Task B

  btrfs_ref_to_path()               btrfs_commit_transaction()
    read_lock(&eb->lock);

                                      btrfs_run_delayed_items()
                                        __btrfs_commit_inode_delayed_items()
                                          __btrfs_update_delayed_inode()
                                            btrfs_lookup_inode()

                                              write_lock(&eb->lock);
                                                --> task waits for lock

    read_lock(&eb->lock);
    --> makes this task hang
        forever (and task B too
of course)

So fix this by avoiding doing the nested read lock, which is easily
avoidable. This issue does not happen if task B calls write_lock() after
task A does the second call to read_lock(), however there does not seem
to exist anything in the documentation that mentions what is the expected
behaviour for recursive locking of rwlocks (leaving the idea that doing
so is not a good usage of rwlocks).

Also, as a side effect necessary for this fix, make sure we do not
needlessly read lock extent buffers when the input path has skip_locking
set (used when called from send).

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
8 years agotarget: Fix LUN_RESET active TMR descriptor handling
Nicholas Bellinger [Tue, 12 Jan 2016 05:53:05 +0000 (21:53 -0800)]
target: Fix LUN_RESET active TMR descriptor handling

[ Upstream commit a6d9bb1c9605cd4f44e2d8290dc4d0e88f20292d ]

This patch fixes a NULL pointer se_cmd->cmd_kref < 0
refcount bug during TMR LUN_RESET with active TMRs,
triggered during se_cmd + se_tmr_req descriptor
shutdown + release via core_tmr_drain_tmr_list().

To address this bug, go ahead and obtain a local
kref_get_unless_zero(&se_cmd->cmd_kref) for active I/O
to set CMD_T_ABORTED, and transport_wait_for_tasks()
followed by the final target_put_sess_cmd() to drop
the local ->cmd_kref.

Also add two new checks within target_tmr_work() to
avoid CMD_T_ABORTED -> TFO->queue_tm_rsp() callbacks
ahead of invoking the backend -> fabric put in
transport_cmd_check_stop_to_fabric().

For good measure, also change core_tmr_release_req()
to use list_del_init() ahead of se_tmr_req memory
free.

Reviewed-by: Quinn Tran <quinn.tran@qlogic.com>
Cc: Himanshu Madhani <himanshu.madhani@qlogic.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>