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523179 commits

Author SHA1 Message Date
Nitin Gupta 25f7f80eab sparc64: Fix numa node distance initialization
[ Upstream commit 36beca6571 ]

Orabug: 22495713

Currently, NUMA node distance matrix is initialized only
when a machine descriptor (MD) exists. However, sun4u
machines (e.g. Sun Blade 2500) do not have an MD and thus
distance values were left uninitialized. The initialization
is now moved such that it happens on both sun4u and sun4v.

Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Tested-by: Mikael Pettersson <mikpelinux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:30 -04:00
David S. Miller 693b8dc4b2 sparc64: Fix bootup regressions on some Kconfig combinations.
[ Upstream commit 49fa523046 ]

The system call tracing bug fix mentioned in the Fixes tag
below increased the amount of assembler code in the sequence
of assembler files included by head_64.S

This caused to total set of code to exceed 0x4000 bytes in
size, which overflows the expression in head_64.S that works
to place swapper_tsb at address 0x408000.

When this is violated, the TSB is not properly aligned, and
also the trap table is not aligned properly either.  All of
this together results in failed boots.

So, do two things:

1) Simplify some code by using ba,a instead of ba/nop to get
   those bytes back.

2) Add a linker script assertion to make sure that if this
   happens again the build will fail.

Fixes: 1a40b95374 ("sparc: Fix system call tracing register handling.")
Reported-by: Meelis Roos <mroos@linux.ee>
Reported-by: Joerg Abraham <joerg.abraham@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:30 -04:00
Mike Frysinger d2e4e89ae8 sparc: Fix system call tracing register handling.
[ Upstream commit 1a40b95374 ]

A system call trace trigger on entry allows the tracing
process to inspect and potentially change the traced
process's registers.

Account for that by reloading the %g1 (syscall number)
and %i0-%i5 (syscall argument) values.  We need to be
careful to revalidate the range of %g1, and reload the
system call table entry it corresponds to into %l7.

Reported-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:30 -04:00
Yuchung Cheng daaaff2715 tcp: record TLP and ER timer stats in v6 stats
[ Upstream commit ce3cf4ec03 ]

The v6 tcp stats scan do not provide TLP and ER timer information
correctly like the v4 version . This patch fixes that.

Fixes: 6ba8a3b19e ("tcp: Tail loss probe (TLP)")
Fixes: eed530b6c6 ("tcp: early retransmit")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:29 -04:00
Edward Cree e2de678c19 sfc: on MC reset, clear PIO buffer linkage in TXQs
[ Upstream commit c0795bf64c ]

Otherwise, if we fail to allocate new PIO buffers, our TXQs will try to
use the old ones, which aren't there any more.

Fixes: 183233bec8 "sfc: Allocate and link PIO buffers; map them with write-combining"
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:29 -04:00
Jason Wang 27b56c6154 tuntap: correctly wake up process during uninit
[ Upstream commit addf8fc4ac ]

We used to check dev->reg_state against NETREG_REGISTERED after each
time we are woke up. But after commit 9e641bdcfa ("net-tun:
restructure tun_do_read for better sleep/wakeup efficiency"), it uses
skb_recv_datagram() which does not check dev->reg_state. This will
result if we delete a tun/tap device after a process is blocked in the
reading. The device will wait for the reference count which was held
by that process for ever.

Fixes this by using RCV_SHUTDOWN which will be checked during
sk_recv_datagram() before trying to wake up the process during uninit.

Fixes: 9e641bdcfa ("net-tun: restructure tun_do_read for better
sleep/wakeup efficiency")
Cc: Eric Dumazet <edumazet@google.com>
Cc: Xi Wang <xii@google.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:29 -04:00
Richard Alpe 8454d6443c tipc: fix nametable publication field in nl compat
[ Upstream commit 03aaaa9b94 ]

The publication field of the old netlink API should contain the
publication key and not the publication reference.

Fixes: 44a8ae94fd (tipc: convert legacy nl name table dump to nl compat)
Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:28 -04:00
Herbert Xu e39cd93be0 netlink: Fix dump skb leak/double free
[ Upstream commit 92964c79b3 ]

When we free cb->skb after a dump, we do it after releasing the
lock.  This means that a new dump could have started in the time
being and we'll end up freeing their skb instead of ours.

This patch saves the skb and module before we unlock so we free
the right memory.

Fixes: 16b304f340 ("netlink: Eliminate kmalloc in netlink dump operation.")
Reported-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
2016-07-10 23:07:28 -04:00
Richard Alpe 49956430d3 tipc: check nl sock before parsing nested attributes
[ Upstream commit 45e093ae28 ]

Make sure the socket for which the user is listing publication exists
before parsing the socket netlink attributes.

Prior to this patch a call without any socket caused a NULL pointer
dereference in tipc_nl_publ_dump().

Tested-and-reported-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.cm>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:28 -04:00
Eric Sandeen 186e7c3872 xfs: print name of verifier if it fails
[ Upstream commit 233135b763 ]

This adds a name to each buf_ops structure, so that if
a verifier fails we can print the type of verifier that
failed it.  Should be a slight debugging aid, I hope.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:28 -04:00
Willy Tarreau 2612a949cf pipe: limit the per-user amount of pages allocated in pipes
[ Upstream commit 759c01142a ]

On no-so-small systems, it is possible for a single process to cause an
OOM condition by filling large pipes with data that are never read. A
typical process filling 4000 pipes with 1 MB of data will use 4 GB of
memory. On small systems it may be tricky to set the pipe max size to
prevent this from happening.

This patch makes it possible to enforce a per-user soft limit above
which new pipes will be limited to a single page, effectively limiting
them to 4 kB each, as well as a hard limit above which no new pipes may
be created for this user. This has the effect of protecting the system
against memory abuse without hurting other users, and still allowing
pipes to work correctly though with less data at once.

The limit are controlled by two new sysctls : pipe-user-pages-soft, and
pipe-user-pages-hard. Both may be disabled by setting them to zero. The
default soft limit allows the default number of FDs per process (1024)
to create pipes of the default size (64kB), thus reaching a limit of 64MB
before starting to create only smaller pipes. With 256 processes limited
to 1024 FDs each, this results in 1024*64kB + (256*1024 - 1024) * 4kB =
1084 MB of memory allocated for a user. The hard limit is disabled by
default to avoid breaking existing applications that make intensive use
of pipes (eg: for splicing).

Reported-by: socketpair@gmail.com
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Mitigates: CVE-2013-4312 (Linux 2.0+)
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:27 -04:00
Huacai Chen e8ebd0cf88 MIPS: Reserve nosave data for hibernation
[ Upstream commit a95d069204 ]

After commit 92923ca3aa ("mm: meminit: only set page reserved
in the memblock region"), the MIPS hibernation is broken. Because pages
in nosave data section should be "reserved", but currently they aren't
set to "reserved" at initialization. This patch makes hibernation work
again.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Steven J . Hill <sjhill@realitydiluted.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12888/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:27 -04:00
Chanwoo Choi 664fcc1169 serial: samsung: Reorder the sequence of clock control when call s3c24xx_serial_set_termios()
[ Upstream commit b8995f527a ]

This patch fixes the broken serial log when changing the clock source
of uart device. Before disabling the original clock source, this patch
enables the new clock source to protect the clock off state for a split second.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:27 -04:00
Jiri Slaby 5ec75b71be tty: vt, return error when con_startup fails
[ Upstream commit 6798df4c5f ]

When csw->con_startup() fails in do_register_con_driver, we return no
error (i.e. 0). This was changed back in 2006 by commit 3e795de763.
Before that we used to return -ENODEV.

So fix the return value to be -ENODEV in that case again.

Fixes: 3e795de763 ("VT binding: Add binding/unbinding support for the VT console")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: "Dan Carpenter" <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:27 -04:00
Paolo Bonzini 87e0b5757e KVM: x86: mask CPUID(0xD,0x1).EAX against host value
[ Upstream commit 316314cae1 ]

This ensures that the guest doesn't see XSAVE extensions
(e.g. xgetbv1 or xsavec) that the host lacks.

Cc: stable@vger.kernel.org
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:27 -04:00
Lars-Peter Clausen 4b6986fcce usb: gadget: f_fs: Fix EFAULT generation for async read operations
[ Upstream commit 332a5b446b ]

In the current implementation functionfs generates a EFAULT for async read
operations if the read buffer size is larger than the URB data size. Since
a application does not necessarily know how much data the host side is
going to send it typically supplies a buffer larger than the actual data,
which will then result in a EFAULT error.

This behaviour was introduced while refactoring the code to use iov_iter
interface in commit c993c39b86 ("gadget/function/f_fs.c: use put iov_iter
into io_data"). The original code took the minimum over the URB size and
the user buffer size and then attempted to copy that many bytes using
copy_to_user(). If copy_to_user() could not copy all data a EFAULT error
was generated. Restore the original behaviour by only generating a EFAULT
error when the number of bytes copied is not the size of the URB and the
target buffer has not been fully filled.

Commit 342f39a6c8 ("usb: gadget: f_fs: fix check in read operation")
already fixed the same problem for the synchronous read path.

Fixes: c993c39b86 ("gadget/function/f_fs.c: use put iov_iter into io_data")
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:26 -04:00
Andy Gross 616ffbf1a5 clk: qcom: msm8916: Fix crypto clock flags
[ Upstream commit 2a0974aa1a ]

This patch adds the CLK_SET_RATE_PARENT flag for the crypto core and
ahb blocks.  Without this flag, clk_set_rate can fail for certain
frequency requests.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
Fixes: 3966fab8b6 ("clk: qcom: Add MSM8916 Global Clock Controller support")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:26 -04:00
Josef Bacik ec2744d3c8 Btrfs: don't use src fd for printk
[ Upstream commit c79b471330 ]

The fd we pass in may not be on a btrfs file system, so don't try to do
BTRFS_I() on it.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:26 -04:00
Lucas Stach 545655ed2e drm/radeon: fix PLL sharing on DCE6.1 (v2)
[ Upstream commit e3c00d8784 ]

On DCE6.1 PPLL2 is exclusively available to UNIPHYA, so it should not
be taken into consideration when looking for an already enabled PLL
to be shared with other outputs.

This fixes the broken VGA port (TRAVIS DP->VGA bridge) on my Richland
based laptop, where the internal display is connected to UNIPHYA through
a TRAVIS DP->LVDS bridge.

Bug:
https://bugs.freedesktop.org/show_bug.cgi?id=78987

v2: agd: add check in radeon_get_shared_nondp_ppll as well, drop
    extra parameter.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:26 -04:00
Gerald Schaefer a36c14ba24 s390/mm: fix asce_bits handling with dynamic pagetable levels
[ Upstream commit 723cacbd9d ]

There is a race with multi-threaded applications between context switch and
pagetable upgrade. In switch_mm() a new user_asce is built from mm->pgd and
mm->context.asce_bits, w/o holding any locks. A concurrent mmap with a
pagetable upgrade on another thread in crst_table_upgrade() could already
have set new asce_bits, but not yet the new mm->pgd. This would result in a
corrupt user_asce in switch_mm(), and eventually in a kernel panic from a
translation exception.

Fix this by storing the complete asce instead of just the asce_bits, which
can then be read atomically from switch_mm(), so that it either sees the
old value or the new value, but no mixture. Both cases are OK. Having the
old value would result in a page fault on access to the higher level memory,
but the fault handler would see the new mm->pgd, if it was a valid access
after the mmap on the other thread has completed. So as worst-case scenario
we would have a page fault loop for the racing thread until the next time
slice.

Also remove dead code and simplify the upgrade/downgrade path, there are no
upgrades from 2 levels, and only downgrades from 3 levels for compat tasks.
There are also no concurrent upgrades, because the mmap_sem is held with
down_write() in do_mmap, so the flush and table checks during upgrade can
be removed.

Reported-by: Michael Munday <munday@ca.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:25 -04:00
Eric Dumazet 90eb6718b9 tcp: refresh skb timestamp at retransmit time
[ Upstream commit 10a81980fc ]

In the very unlikely case __tcp_retransmit_skb() can not use the cloning
done in tcp_transmit_skb(), we need to refresh skb_mstamp before doing
the copy and transmit, otherwise TCP TS val will be an exact copy of
original transmit.

Fixes: 7faee5c0d5 ("tcp: remove TCP_SKB_CB(skb)->when")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:25 -04:00
Kangjie Lu b2b95b3fbd net: fix a kernel infoleak in x25 module
[ Upstream commit 79e4865032 ]

Stack object "dte_facilities" is allocated in x25_rx_call_request(),
which is supposed to be initialized in x25_negotiate_facilities.
However, 5 fields (8 bytes in total) are not initialized. This
object is then copied to userland via copy_to_user, thus infoleak
occurs.

Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:25 -04:00
Nikolay Aleksandrov 806d70c7da net: bridge: fix old ioctl unlocked net device walk
[ Upstream commit 31ca0458a6 ]

get_bridge_ifindices() is used from the old "deviceless" bridge ioctl
calls which aren't called with rtnl held. The comment above says that it is
called with rtnl but that is not really the case.
Here's a sample output from a test ASSERT_RTNL() which I put in
get_bridge_ifindices and executed "brctl show":
[  957.422726] RTNL: assertion failed at net/bridge//br_ioctl.c (30)
[  957.422925] CPU: 0 PID: 1862 Comm: brctl Tainted: G        W  O
4.6.0-rc4+ #157
[  957.423009] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.8.1-20150318_183358- 04/01/2014
[  957.423009]  0000000000000000 ffff880058adfdf0 ffffffff8138dec5
0000000000000400
[  957.423009]  ffffffff81ce8380 ffff880058adfe58 ffffffffa05ead32
0000000000000001
[  957.423009]  00007ffec1a444b0 0000000000000400 ffff880053c19130
0000000000008940
[  957.423009] Call Trace:
[  957.423009]  [<ffffffff8138dec5>] dump_stack+0x85/0xc0
[  957.423009]  [<ffffffffa05ead32>]
br_ioctl_deviceless_stub+0x212/0x2e0 [bridge]
[  957.423009]  [<ffffffff81515beb>] sock_ioctl+0x22b/0x290
[  957.423009]  [<ffffffff8126ba75>] do_vfs_ioctl+0x95/0x700
[  957.423009]  [<ffffffff8126c159>] SyS_ioctl+0x79/0x90
[  957.423009]  [<ffffffff8163a4c0>] entry_SYSCALL_64_fastpath+0x23/0xc1

Since it only reads bridge ifindices, we can use rcu to safely walk the net
device list. Also remove the wrong rtnl comment above.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:25 -04:00
Ian Campbell 8817c1b1da VSOCK: do not disconnect socket when peer has shutdown SEND only
[ Upstream commit dedc58e067 ]

The peer may be expecting a reply having sent a request and then done a
shutdown(SHUT_WR), so tearing down the whole socket at this point seems
wrong and breaks for me with a client which does a SHUT_WR.

Looking at other socket family's stream_recvmsg callbacks doing a shutdown
here does not seem to be the norm and removing it does not seem to have
had any adverse effects that I can see.

I'm using Stefan's RFC virtio transport patches, I'm unsure of the impact
on the vmci transport.

Signed-off-by: Ian Campbell <ian.campbell@docker.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Cc: Andy King <acking@vmware.com>
Cc: Dmitry Torokhov <dtor@vmware.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: Adit Ranadive <aditr@vmware.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:25 -04:00
Daniel Jurgens 8bba162551 net/mlx4_en: Fix endianness bug in IPV6 csum calculation
[ Upstream commit 82d69203df ]

Use htons instead of unconditionally byte swapping nexthdr.  On a little
endian systems shifting the byte is correct behavior, but it results in
incorrect csums on big endian architectures.

Fixes: f8c6455bb0 ('net/mlx4_en: Extend checksum offloading by CHECKSUM COMPLETE')
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Carol Soto <clsoto@us.ibm.com>
Tested-by: Carol Soto <clsoto@us.ibm.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:24 -04:00
Kangjie Lu 9a9390bcf5 net: fix infoleak in rtnetlink
[ Upstream commit 5f8e44741f ]

The stack object “map” has a total size of 32 bytes. Its last 4
bytes are padding generated by compiler. These padding bytes are
not initialized and sent out via “nla_put”.

Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:24 -04:00
Kangjie Lu 5923f46563 net: fix infoleak in llc
[ Upstream commit b8670c09f3 ]

The stack object “info” has a total size of 12 bytes. Its last byte
is padding which is not initialized and leaked via “put_cmsg”.

Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:24 -04:00
Uwe Kleine-König 9a7e38d01e net: fec: only clear a queue's work bit if the queue was emptied
[ Upstream commit 1c021bb717 ]

In the receive path a queue's work bit was cleared unconditionally even
if fec_enet_rx_queue only read out a part of the available packets from
the hardware. This resulted in not reading any packets in the next napi
turn and so packets were delayed or lost.

The obvious fix is to only clear a queue's bit when the queue was
emptied.

Fixes: 4d494cdc92 ("net: fec: change data structure to support multiqueue")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Fugang Duan <fugang.duan@nxp.com>
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:24 -04:00
Neil Horman 5305392b44 netem: Segment GSO packets on enqueue
[ Upstream commit 6071bd1aa1 ]

This was recently reported to me, and reproduced on the latest net kernel,
when attempting to run netperf from a host that had a netem qdisc attached
to the egress interface:

[  788.073771] ---------------------[ cut here ]---------------------------
[  788.096716] WARNING: at net/core/dev.c:2253 skb_warn_bad_offload+0xcd/0xda()
[  788.129521] bnx2: caps=(0x00000001801949b3, 0x0000000000000000) len=2962
data_len=0 gso_size=1448 gso_type=1 ip_summed=3
[  788.182150] Modules linked in: sch_netem kvm_amd kvm crc32_pclmul ipmi_ssif
ghash_clmulni_intel sp5100_tco amd64_edac_mod aesni_intel lrw gf128mul
glue_helper ablk_helper edac_mce_amd cryptd pcspkr sg edac_core hpilo ipmi_si
i2c_piix4 k10temp fam15h_power hpwdt ipmi_msghandler shpchp acpi_power_meter
pcc_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c
sd_mod crc_t10dif crct10dif_generic mgag200 syscopyarea sysfillrect sysimgblt
i2c_algo_bit drm_kms_helper ahci ata_generic pata_acpi ttm libahci
crct10dif_pclmul pata_atiixp tg3 libata crct10dif_common drm crc32c_intel ptp
serio_raw bnx2 r8169 hpsa pps_core i2c_core mii dm_mirror dm_region_hash dm_log
dm_mod
[  788.465294] CPU: 16 PID: 0 Comm: swapper/16 Tainted: G        W
------------   3.10.0-327.el7.x86_64 #1
[  788.511521] Hardware name: HP ProLiant DL385p Gen8, BIOS A28 12/17/2012
[  788.542260]  ffff880437c036b8 f7afc56532a53db9 ffff880437c03670
ffffffff816351f1
[  788.576332]  ffff880437c036a8 ffffffff8107b200 ffff880633e74200
ffff880231674000
[  788.611943]  0000000000000001 0000000000000003 0000000000000000
ffff880437c03710
[  788.647241] Call Trace:
[  788.658817]  <IRQ>  [<ffffffff816351f1>] dump_stack+0x19/0x1b
[  788.686193]  [<ffffffff8107b200>] warn_slowpath_common+0x70/0xb0
[  788.713803]  [<ffffffff8107b29c>] warn_slowpath_fmt+0x5c/0x80
[  788.741314]  [<ffffffff812f92f3>] ? ___ratelimit+0x93/0x100
[  788.767018]  [<ffffffff81637f49>] skb_warn_bad_offload+0xcd/0xda
[  788.796117]  [<ffffffff8152950c>] skb_checksum_help+0x17c/0x190
[  788.823392]  [<ffffffffa01463a1>] netem_enqueue+0x741/0x7c0 [sch_netem]
[  788.854487]  [<ffffffff8152cb58>] dev_queue_xmit+0x2a8/0x570
[  788.880870]  [<ffffffff8156ae1d>] ip_finish_output+0x53d/0x7d0
...

The problem occurs because netem is not prepared to handle GSO packets (as it
uses skb_checksum_help in its enqueue path, which cannot manipulate these
frames).

The solution I think is to simply segment the skb in a simmilar fashion to the
way we do in __dev_queue_xmit (via validate_xmit_skb), with some minor changes.
When we decide to corrupt an skb, if the frame is GSO, we segment it, corrupt
the first segment, and enqueue the remaining ones.

tested successfully by myself on the latest net kernel, to which this applies

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Jamal Hadi Salim <jhs@mojatatu.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: netem@lists.linux-foundation.org
CC: eric.dumazet@gmail.com
CC: stephen@networkplumber.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>
2016-07-10 23:07:23 -04:00
WANG Cong dfc58a04d1 sch_dsmark: update backlog as well
[ Upstream commit bdf17661f6 ]

Similarly, we need to update backlog too when we update qlen.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-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>
2016-07-10 23:07:23 -04:00
WANG Cong 64e1762ae4 sch_htb: update backlog as well
[ Upstream commit 431e3a8e36 ]

We saw qlen!=0 but backlog==0 on our production machine:

qdisc htb 1: dev eth0 root refcnt 2 r2q 10 default 1 direct_packets_stat 0 ver 3.17
 Sent 172680457356 bytes 222469449 pkt (dropped 0, overlimits 123575834 requeues 0)
 backlog 0b 72p requeues 0

The problem is we only count qlen for HTB qdisc but not backlog.
We need to update backlog too when we update qlen, so that we
can at least know the average packet length.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-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>
2016-07-10 23:07:23 -04:00
WANG Cong 236094acb4 net_sched: update hierarchical backlog too
[ Upstream commit 2ccccf5fb4 ]

When the bottom qdisc decides to, for example, drop some packet,
it calls qdisc_tree_decrease_qlen() to update the queue length
for all its ancestors, we need to update the backlog too to
keep the stats on root qdisc accurate.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-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>
2016-07-10 23:07:23 -04:00
WANG Cong 11316d7eef net_sched: introduce qdisc_replace() helper
[ Upstream commit 86a7996cc8 ]

Remove nearly duplicated code and prepare for the following patch.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-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>
2016-07-10 23:07:22 -04:00
Jann Horn 7b6460337e bpf: fix double-fdput in replace_map_fd_with_map_ptr()
[ Upstream commit 8358b02bf6 ]

When bpf(BPF_PROG_LOAD, ...) was invoked with a BPF program whose bytecode
references a non-map file descriptor as a map file descriptor, the error
handling code called fdput() twice instead of once (in __bpf_map_get() and
in replace_map_fd_with_map_ptr()). If the file descriptor table of the
current task is shared, this causes f_count to be decremented too much,
allowing the struct file to be freed while it is still in use
(use-after-free). This can be exploited to gain root privileges by an
unprivileged user.

This bug was introduced in
commit 0246e64d9a ("bpf: handle pseudo BPF_LD_IMM64 insn"), but is only
exploitable since
commit 1be7f75d16 ("bpf: enable non-root eBPF programs") because
previously, CAP_SYS_ADMIN was required to reach the vulnerable code.

(posted publicly according to request by maintainer)

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:22 -04:00
Eric Dumazet eeee948a65 net/mlx4_en: fix spurious timestamping callbacks
[ Upstream commit fc96256c90 ]

When multiple skb are TX-completed in a row, we might incorrectly keep
a timestamp of a prior skb and cause extra work.

Fixes: ec693d4701 ("net/mlx4_en: Add HW timestamping (TS) support")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:22 -04:00
Paolo Abeni 2c5ac2bfe5 ipv4/fib: don't warn when primary address is missing if in_dev is dead
[ Upstream commit 391a20333b ]

After commit fbd40ea018 ("ipv4: Don't do expensive useless work
during inetdev destroy.") when deleting an interface,
fib_del_ifaddr() can be executed without any primary address
present on the dead interface.

The above is safe, but triggers some "bug: prim == NULL" warnings.

This commit avoids warning if the in_dev is dead

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:22 -04:00
Simon Horman 303c69a17d openvswitch: use flow protocol when recalculating ipv6 checksums
[ Upstream commit b4f70527f0 ]

When using masked actions the ipv6_proto field of an action
to set IPv6 fields may be zero rather than the prevailing protocol
which will result in skipping checksum recalculation.

This patch resolves the problem by relying on the protocol
in the flow key rather than that in the set field action.

Fixes: 83d2b9ba1a ("net: openvswitch: Support masked set actions.")
Cc: Jarno Rajahalme <jrajahalme@nicira.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:22 -04:00
Ben Hutchings a2e388f253 atl2: Disable unimplemented scatter/gather feature
[ Upstream commit f43bfaeddc ]

atl2 includes NETIF_F_SG in hw_features even though it has no support
for non-linear skbs.  This bug was originally harmless since the
driver does not claim to implement checksum offload and that used to
be a requirement for SG.

Now that SG and checksum offload are independent features, if you
explicitly enable SG *and* use one of the rare protocols that can use
SG without checkusm offload, this potentially leaks sensitive
information (before you notice that it just isn't working).  Therefore
this obscure bug has been designated CVE-2016-2117.

Reported-by: Justin Yackoski <jyackoski@crypto-nite.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: ec5f061564 ("net: Kill link between CSUM and SG features.")
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:21 -04:00
Alexei Starovoitov a4e1611c8b bpf/verifier: reject invalid LD_ABS | BPF_DW instruction
[ Upstream commit d82bccc690 ]

verifier must check for reserved size bits in instruction opcode and
reject BPF_LD | BPF_ABS | BPF_DW and BPF_LD | BPF_IND | BPF_DW instructions,
otherwise interpreter will WARN_RATELIMIT on them during execution.

Fixes: ddd872bc30 ("bpf: verifier: add checks for BPF_ABS | BPF_IND instructions")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:21 -04:00
Lars Persson 5730fd5d72 net: sched: do not requeue a NULL skb
[ Upstream commit 3dcd493fbe ]

A failure in validate_xmit_skb_list() triggered an unconditional call
to dev_requeue_skb with skb=NULL. This slowly grows the queue
discipline's qlen count until all traffic through the queue stops.

We take the optimistic approach and continue running the queue after a
failure since it is unknown if later packets also will fail in the
validate path.

Fixes: 55a93b3ea7 ("qdisc: validate skb without holding lock")
Signed-off-by: Lars Persson <larper@axis.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>
2016-07-10 23:07:21 -04:00
Mathias Krause 4b5223be98 packet: fix heap info leak in PACKET_DIAG_MCLIST sock_diag interface
[ Upstream commit 309cf37fe2 ]

Because we miss to wipe the remainder of i->addr[] in packet_mc_add(),
pdiag_put_mclist() leaks uninitialized heap bytes via the
PACKET_DIAG_MCLIST netlink attribute.

Fix this by explicitly memset(0)ing the remaining bytes in i->addr[].

Fixes: eea68e2f1a ("packet: Report socket mclist info via diag module")
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:21 -04:00
Chris Friesen 80565d16c3 route: do not cache fib route info on local routes with oif
[ Upstream commit d6d5e999e5 ]

For local routes that require a particular output interface we do not want
to cache the result.  Caching the result causes incorrect behaviour when
there are multiple source addresses on the interface.  The end result
being that if the intended recipient is waiting on that interface for the
packet he won't receive it because it will be delivered on the loopback
interface and the IP_PKTINFO ipi_ifindex will be set to the loopback
interface as well.

This can be tested by running a program such as "dhcp_release" which
attempts to inject a packet on a particular interface so that it is
received by another program on the same board.  The receiving process
should see an IP_PKTINFO ipi_ifndex value of the source interface
(e.g., eth1) instead of the loopback interface (e.g., lo).  The packet
will still appear on the loopback interface in tcpdump but the important
aspect is that the CMSG info is correct.

Sample dhcp_release command line:

   dhcp_release eth1 192.168.204.222 02:11:33:22:44:66

Signed-off-by: Allain Legacy <allain.legacy@windriver.com>
Signed off-by: Chris Friesen <chris.friesen@windriver.com>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:20 -04:00
David S. Miller 1ea4df4a26 decnet: Do not build routes to devices without decnet private data.
[ Upstream commit a36a0d4008 ]

In particular, make sure we check for decnet private presence
for loopback devices.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:20 -04:00
Srinivas Pandruvada 51319f40e5 ACPI / processor: Request native thermal interrupt handling via _OSC
[ Upstream commit a21211672c ]

There are several reports of freeze on enabling HWP (Hardware PStates)
feature on Skylake-based systems by the Intel P-states driver. The root
cause is identified as the HWP interrupts causing BIOS code to freeze.

HWP interrupts use the thermal LVT which can be handled by Linux
natively, but on the affected Skylake-based systems SMM will respond
to it by default.  This is a problem for several reasons:
 - On the affected systems the SMM thermal LVT handler is broken (it
   will crash when invoked) and a BIOS update is necessary to fix it.
 - With thermal interrupt handled in SMM we lose all of the reporting
   features of the arch/x86/kernel/cpu/mcheck/therm_throt driver.
 - Some thermal drivers like x86-package-temp depend on the thermal
   threshold interrupts signaled via the thermal LVT.
 - The HWP interrupts are useful for debugging and tuning
   performance (if the kernel can handle them).
The native handling of thermal interrupts needs to be enabled
because of that.

This requires some way to tell SMM that the OS can handle thermal
interrupts.  That can be done by using _OSC/_PDC in processor
scope very early during ACPI initialization.

The meaning of _OSC/_PDC bit 12 in processor scope is whether or
not the OS supports native handling of interrupts for Collaborative
Processor Performance Control (CPPC) notifications.  Since on
HWP-capable systems CPPC is a firmware interface to HWP, setting
this bit effectively tells the firmware that the OS will handle
thermal interrupts natively going forward.

For details on _OSC/_PDC refer to:
http://www.intel.com/content/www/us/en/standards/processor-vendor-specific-acpi-specification.html

To implement the _OSC/_PDC handshake as described, introduce a new
function, acpi_early_processor_osc(), that walks the ACPI
namespace looking for ACPI processor objects and invokes _OSC for
them with bit 12 in the capabilities buffer set and terminates the
namespace walk on the first success.

Also modify intel_thermal_interrupt() to clear HWP status bits in
the HWP_STATUS MSR to acknowledge HWP interrupts (which prevents
them from firing continuously).

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Subject & changelog, function rename ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:20 -04:00
Richard Leitner fd4453a9c8 iio: ak8975: fix maybe-uninitialized warning
[ Upstream commit 05be8d4101 ]

If i2c_device_id *id is NULL and acpi_match_device returns NULL too,
then chipset may be unitialized when accessing &ak_def_array[chipset] in
ak8975_probe. Therefore initialize chipset to AK_MAX_TYPE, which will
return an error when not changed.

This patch fixes the following maybe-uninitialized warning:

drivers/iio/magnetometer/ak8975.c: In function ‘ak8975_probe’:
drivers/iio/magnetometer/ak8975.c:788:14: warning: ‘chipset’ may be used
uninitialized in this function [-Wmaybe-uninitialized]
  data->def = &ak_def_array[chipset];

Signed-off-by: Richard Leitner <dev@g0hl1n.net>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:20 -04:00
Sven Eckelmann b55c212a0f batman-adv: Reduce refcnt of removed router when updating route
[ Upstream commit d1a65f1741 ]

_batadv_update_route rcu_derefences orig_ifinfo->router outside of a
spinlock protected region to print some information messages to the debug
log. But this pointer is not checked again when the new pointer is assigned
in the spinlock protected region. Thus is can happen that the value of
orig_ifinfo->router changed in the meantime and thus the reference counter
of the wrong router gets reduced after the spinlock protected region.

Just rcu_dereferencing the value of orig_ifinfo->router inside the spinlock
protected region (which also set the new pointer) is enough to get the
correct old router object.

Fixes: e1a5382f97 ("batman-adv: Make orig_node->router an rcu protected pointer")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:19 -04:00
Linus Lüssing eaa401a078 batman-adv: Fix broadcast/ogm queue limit on a removed interface
[ Upstream commit c4fdb6cff2 ]

When removing a single interface while a broadcast or ogm packet is
still pending then we will free the forward packet without releasing the
queue slots again.

This patch is supposed to fix this issue.

Fixes: 6d5808d4ae ("batman-adv: Add missing hardif_free_ref in forw_packet_free")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
[sven@narfation.org: fix conflicts with current version]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:19 -04:00
Sven Eckelmann f7ac631102 batman-adv: Check skb size before using encapsulated ETH+VLAN header
[ Upstream commit c78296665c ]

The encapsulated ethernet and VLAN header may be outside the received
ethernet frame. Thus the skb buffer size has to be checked before it can be
parsed to find out if it encapsulates another batman-adv packet.

Fixes: 420193573f ("batman-adv: softif bridge loop avoidance")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-07-10 23:07:19 -04:00
Jason Baron 7b1f624b9e mm: update min_free_kbytes from khugepaged after core initialization
[ Upstream commit bc22af74f2 ]

Khugepaged attempts to raise min_free_kbytes if its set too low.
However, on boot khugepaged sets min_free_kbytes first from
subsys_initcall(), and then the mm 'core' over-rides min_free_kbytes
after from init_per_zone_wmark_min(), via a module_init() call.

Khugepaged used to use a late_initcall() to set min_free_kbytes (such
that it occurred after the core initialization), however this was
removed when the initialization of min_free_kbytes was integrated into
the starting of the khugepaged thread.

The fix here is simply to invoke the core initialization using a
core_initcall() instead of module_init(), such that the previous
initialization ordering is restored.  I didn't restore the
late_initcall() since start_stop_khugepaged() already sets
min_free_kbytes via set_recommended_min_free_kbytes().

This was noticed when we had a number of page allocation failures when
moving a workload to a kernel with this new initialization ordering.  On
an 8GB system this restores min_free_kbytes back to 67584 from 11365
when CONFIG_TRANSPARENT_HUGEPAGE=y is set and either
CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS=y or
CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y.

Fixes: 79553da293 ("thp: cleanup khugepaged startup")
Signed-off-by: Jason Baron <jbaron@akamai.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: David Rientjes <rientjes@google.com>
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>
2016-07-10 23:07:19 -04:00
Mathias Krause 93c4863f44 proc: prevent accessing /proc/<PID>/environ until it's ready
[ Upstream commit 8148a73c99 ]

If /proc/<PID>/environ gets read before the envp[] array is fully set up
in create_{aout,elf,elf_fdpic,flat}_tables(), we might end up trying to
read more bytes than are actually written, as env_start will already be
set but env_end will still be zero, making the range calculation
underflow, allowing to read beyond the end of what has been written.

Fix this as it is done for /proc/<PID>/cmdline by testing env_end for
zero.  It is, apparently, intentionally set last in create_*_tables().

This bug was found by the PaX size_overflow plugin that detected the
arithmetic underflow of 'this_len = env_end - (env_start + src)' when
env_end is still zero.

The expected consequence is that userland trying to access
/proc/<PID>/environ of a not yet fully set up process may get
inconsistent data as we're in the middle of copying in the environment
variables.

Fixes: https://forums.grsecurity.net/viewtopic.php?f=3&t=4363
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=116461
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: Pax Team <pageexec@freemail.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Jarod Wilson <jarod@redhat.com>
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>
2016-07-10 23:07:18 -04:00