715722 Commits

Author SHA1 Message Date
Sven Eckelmann
18733cfe41 batman-adv: Prevent duplicated nc_node entry
[ Upstream commit fa122fec8640eb7186ce5a41b83a4c1744ceef8f ]

The function batadv_nc_get_nc_node is responsible for adding new nc_nodes
to the in_coding_list and out_coding_list. It first checks whether the
entry already is in the list or not. If it is, then the creation of a new
entry is aborted.

But the lock for the list is only held when the list is really modified.
This could lead to duplicated entries because another context could create
an entry with the same key between the check and the list manipulation.

The check and the manipulation of the list must therefore be in the same
locked code section.

Fixes: d56b1705e28c ("batman-adv: network coding - detect coding nodes and remove these after timeout")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-20 09:48:48 +02:00
Sven Eckelmann
3b38bed330 batman-adv: Prevent duplicated gateway_node entry
[ Upstream commit dff9bc42ab0b2d38c5e90ddd79b238fed5b4c7ad ]

The function batadv_gw_node_add is responsible for adding new gw_node to
the gateway_list. It is expecting that the caller already checked that
there is not already an entry with the same key or not.

But the lock for the list is only held when the list is really modified.
This could lead to duplicated entries because another context could create
an entry with the same key between the check and the list manipulation.

The check and the manipulation of the list must therefore be in the same
locked code section.

Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-20 09:48:48 +02:00
Sven Eckelmann
c553f7e514 batman-adv: Fix segfault when writing to sysfs elp_interval
[ Upstream commit a25bab9d723a08bd0bdafb1529faf9094c690b70 ]

The per hardif sysfs file "batman_adv/elp_interval" is using the generic
functions to store/show uint values. The helper __batadv_store_uint_attr
requires the softif net_device as parameter to print the resulting change
as info text when the users writes to this file. It uses the helper
function batadv_info to add it at the same time to the kernel ring buffer
and to the batman-adv debug log (when CONFIG_BATMAN_ADV_DEBUG is enabled).

The function batadv_info requires as first parameter the batman-adv softif
net_device. This parameter is then used to find the private buffer which
contains the debug log for this batman-adv interface. But
batadv_store_throughput_override used as first argument the slave
net_device. This slave device doesn't have the batadv_priv private data
which is access by batadv_info.

Writing to this file with CONFIG_BATMAN_ADV_DEBUG enabled can either lead
to a segfault or to memory corruption.

Fixes: 0744ff8fa8fa ("batman-adv: Add hard_iface specific sysfs wrapper macros for UINT")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-20 09:48:48 +02:00
Sven Eckelmann
acdaf28d8c batman-adv: Fix segfault when writing to throughput_override
[ Upstream commit b9fd14c20871e6189f635e49b32d7789e430b3c8 ]

The per hardif sysfs file "batman_adv/throughput_override" prints the
resulting change as info text when the users writes to this file. It uses
the helper function batadv_info to add it at the same time to the kernel
ring buffer and to the batman-adv debug log (when CONFIG_BATMAN_ADV_DEBUG
is enabled).

The function batadv_info requires as first parameter the batman-adv softif
net_device. This parameter is then used to find the private buffer which
contains the debug log for this batman-adv interface. But
batadv_store_throughput_override used as first argument the slave
net_device. This slave device doesn't have the batadv_priv private data
which is access by batadv_info.

Writing to this file with CONFIG_BATMAN_ADV_DEBUG enabled can either lead
to a segfault or to memory corruption.

Fixes: 0b5ecc6811bd ("batman-adv: add throughput override attribute to hard_ifaces")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-20 09:48:48 +02:00
Sven Eckelmann
fa04cc5e7b batman-adv: Avoid probe ELP information leak
[ Upstream commit 88d0895d0ea9d4431507d576c963f2ff9918144d ]

The probe ELPs for WiFi interfaces are expanded to contain at least
BATADV_ELP_MIN_PROBE_SIZE bytes. This is usually a lot more than the
number of bytes which the template ELP packet requires.

These extra padding bytes were not initialized and thus could contain data
which were previously stored at the same location. It is therefore required
to set it to some predefined or random values to avoid leaking private
information from the system transmitting these kind of packets.

Fixes: e4623c913508 ("batman-adv: Avoid probe ELP information leak")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-20 09:48:47 +02:00
Jozef Balga
88be243901 media: af9035: prevent buffer overflow on write
[ Upstream commit 312f73b648626a0526a3aceebb0a3192aaba05ce ]

When less than 3 bytes are written to the device, memcpy is called with
negative array size which leads to buffer overflow and kernel panic. This
patch adds a condition and returns -EOPNOTSUPP instead.
Fixes bugzilla issue 64871

[mchehab+samsung@kernel.org: fix a merge conflict and changed the
 condition to match the patch's comment, e. g. len == 3 could
 also be valid]
Signed-off-by: Jozef Balga <jozef.balga@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-20 09:48:47 +02:00
Greg Kroah-Hartman
8263087bf6 Linux 4.14.77 2018-10-18 09:16:28 +02:00
Jiri Olsa
d0c9f9f9fb perf tools: Fix snprint warnings for gcc 8
commit 77f18153c080855e1c3fb520ca31a4e61530121d upstream.

With gcc 8 we get new set of snprintf() warnings that breaks the
compilation, one example:

  tests/mem.c: In function ‘check’:
  tests/mem.c:19:48: error: ‘%s’ directive output may be truncated writing \
        up to 99 bytes into a region of size 89 [-Werror=format-truncation=]
    snprintf(failure, sizeof failure, "unexpected %s", out);

The gcc docs says:

 To avoid the warning either use a bigger buffer or handle the
 function's return value which indicates whether or not its output
 has been truncated.

Given that all these warnings are harmless, because the code either
properly fails due to uncomplete file path or we don't care for
truncated output at all, I'm changing all those snprintf() calls to
scnprintf(), which actually 'checks' for the snprint return value so the
gcc stays silent.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Link: http://lkml.kernel.org/r/20180319082902.4518-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:28 +02:00
Russell King
57bff812c4 ARM: spectre-v1: mitigate user accesses
Commit a3c0f84765bb429ba0fd23de1c57b5e1591c9389 upstream.

Spectre variant 1 attacks are about this sequence of pseudo-code:

	index = load(user-manipulated pointer);
	access(base + index * stride);

In order for the cache side-channel to work, the access() must me made
to memory which userspace can detect whether cache lines have been
loaded.  On 32-bit ARM, this must be either user accessible memory, or
a kernel mapping of that same user accessible memory.

The problem occurs when the load() speculatively loads privileged data,
and the subsequent access() is made to user accessible memory.

Any load() which makes use of a user-maniplated pointer is a potential
problem if the data it has loaded is used in a subsequent access.  This
also applies for the access() if the data loaded by that access is used
by a subsequent access.

Harden the get_user() accessors against Spectre attacks by forcing out
of bounds addresses to a NULL pointer.  This prevents get_user() being
used as the load() step above.  As a side effect, put_user() will also
be affected even though it isn't implicated.

Also harden copy_from_user() by redoing the bounds check within the
arm_copy_from_user() code, and NULLing the pointer if out of bounds.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:28 +02:00
Russell King
4a1948d692 ARM: spectre-v1: use get_user() for __get_user()
Commit b1cd0a14806321721aae45f5446ed83a3647c914 upstream.

Fixing __get_user() for spectre variant 1 is not sane: we would have to
add address space bounds checking in order to validate that the location
should be accessed, and then zero the address if found to be invalid.

Since __get_user() is supposed to avoid the bounds check, and this is
exactly what get_user() does, there's no point having two different
implementations that are doing the same thing.  So, when the Spectre
workarounds are required, make __get_user() an alias of get_user().

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:28 +02:00
Russell King
f64824a3d4 ARM: use __inttype() in get_user()
Commit d09fbb327d670737ab40fd8bbb0765ae06b8b739 upstream.

Borrow the x86 implementation of __inttype() to use in get_user() to
select an integer type suitable to temporarily hold the result value.
This is necessary to avoid propagating the volatile nature of the
result argument, which can cause the following warning:

lib/iov_iter.c:413:5: warning: optimization may eliminate reads and/or writes to register variables [-Wvolatile-register-var]

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:28 +02:00
Russell King
70b96be10d ARM: oabi-compat: copy semops using __copy_from_user()
Commit 8c8484a1c18e3231648f5ba7cc5ffb7fd70b3ca4 upstream.

__get_user_error() is used as a fast accessor to make copying structure
members as efficient as possible.  However, with software PAN and the
recent Spectre variant 1, the efficiency is reduced as these are no
longer fast accessors.

In the case of software PAN, it has to switch the domain register around
each access, and with Spectre variant 1, it would have to repeat the
access_ok() check for each access.

Rather than using __get_user_error() to copy each semops element member,
copy each semops element in full using __copy_from_user().

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:28 +02:00
Russell King
38752f4174 ARM: vfp: use __copy_from_user() when restoring VFP state
Commit 42019fc50dfadb219f9e6ddf4c354f3837057d80 upstream.

__get_user_error() is used as a fast accessor to make copying structure
members in the signal handling path as efficient as possible.  However,
with software PAN and the recent Spectre variant 1, the efficiency is
reduced as these are no longer fast accessors.

In the case of software PAN, it has to switch the domain register around
each access, and with Spectre variant 1, it would have to repeat the
access_ok() check for each access.

Use __copy_from_user() rather than __get_user_err() for individual
members when restoring VFP state.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:28 +02:00
Russell King
faac72dc91 ARM: signal: copy registers using __copy_from_user()
Commit c32cd419d6650e42b9cdebb83c672ec945e6bd7e upstream.

__get_user_error() is used as a fast accessor to make copying structure
members in the signal handling path as efficient as possible.  However,
with software PAN and the recent Spectre variant 1, the efficiency is
reduced as these are no longer fast accessors.

In the case of software PAN, it has to switch the domain register around
each access, and with Spectre variant 1, it would have to repeat the
access_ok() check for each access.

It becomes much more efficient to use __copy_from_user() instead, so
let's use this for the ARM integer registers.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Russell King
b690ec0dc7 ARM: spectre-v1: fix syscall entry
Commit 10573ae547c85b2c61417ff1a106cffbfceada35 upstream.

Prevent speculation at the syscall table decoding by clamping the index
used to zero on invalid system call numbers, and using the csdb
speculative barrier.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Russell King
4186f7cfa1 ARM: spectre-v1: add array_index_mask_nospec() implementation
Commit 1d4238c56f9816ce0f9c8dbe42d7f2ad81cb6613 upstream.

Add an implementation of the array_index_mask_nospec() function for
mitigating Spectre variant 1 throughout the kernel.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Russell King
f6909113ad ARM: spectre-v1: add speculation barrier (csdb) macros
Commit a78d156587931a2c3b354534aa772febf6c9e855 upstream.

Add assembly and C macros for the new CSDB instruction.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Russell King
e7fc401a88 ARM: KVM: report support for SMCCC_ARCH_WORKAROUND_1
Commit add5609877c6785cc002c6ed7e008b1d61064439 upstream.

Report support for SMCCC_ARCH_WORKAROUND_1 to KVM guests for affected
CPUs.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Russell King
8502541ee2 ARM: KVM: Add SMCCC_ARCH_WORKAROUND_1 fast handling
Commit b800acfc70d9fb81fbd6df70f2cf5e20f70023d0 upstream.

We want SMCCC_ARCH_WORKAROUND_1 to be fast. As fast as possible.
So let's intercept it as early as we can by testing for the
function call number as soon as we've identified a HVC call
coming from the guest.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Russell King
ee4e537d3a ARM: spectre-v2: KVM: invalidate icache on guest exit for Brahma B15
Commit 3c908e16396d130608e831b7fac4b167a2ede6ba upstream.

Include Brahma B15 in the Spectre v2 KVM workarounds.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Marc Zyngier
1df9a0a820 ARM: KVM: invalidate icache on guest exit for Cortex-A15
Commit 0c47ac8cd157727e7a532d665d6fb1b5fd333977 upstream.

In order to avoid aliasing attacks against the branch predictor
on Cortex-A15, let's invalidate the BTB on guest exit, which can
only be done by invalidating the icache (with ACTLR[0] being set).

We use the same hack as for A12/A17 to perform the vector decoding.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Marc Zyngier
75e48eff8a ARM: KVM: invalidate BTB on guest exit for Cortex-A12/A17
Commit 3f7e8e2e1ebda787f156ce46e3f0a9ce2833fa4f upstream.

In order to avoid aliasing attacks against the branch predictor,
let's invalidate the BTB on guest exit. This is made complicated
by the fact that we cannot take a branch before invalidating the
BTB.

We only apply this to A12 and A17, which are the only two ARM
cores on which this useful.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:27 +02:00
Russell King
6d75fe7ed2 ARM: spectre-v2: warn about incorrect context switching functions
Commit c44f366ea7c85e1be27d08f2f0880f4120698125 upstream.

Warn at error level if the context switching function is not what we
are expecting.  This can happen with big.Little systems, which we
currently do not support.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
510155b2d9 ARM: spectre-v2: add firmware based hardening
Commit 10115105cb3aa17b5da1cb726ae8dd5f6854bd93 upstream.

Add firmware based hardening for cores that require more complex
handling in firmware.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
5ab8c6e887 ARM: spectre-v2: harden user aborts in kernel space
Commit f5fe12b1eaee220ce62ff9afb8b90929c396595f upstream.

In order to prevent aliasing attacks on the branch predictor,
invalidate the BTB or instruction cache on CPUs that are known to be
affected when taking an abort on a address that is outside of a user
task limit:

Cortex A8, A9, A12, A17, A73, A75: flush BTB.
Cortex A15, Brahma B15: invalidate icache.

If the IBE bit is not set, then there is little point to enabling the
workaround.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
81b215a5b8 ARM: spectre-v2: add Cortex A8 and A15 validation of the IBE bit
Commit e388b80288aade31135aca23d32eee93dd106795 upstream.

When the branch predictor hardening is enabled, firmware must have set
the IBE bit in the auxiliary control register.  If this bit has not
been set, the Spectre workarounds will not be functional.

Add validation that this bit is set, and print a warning at alert level
if this is not the case.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
3e52aff79d ARM: spectre-v2: harden branch predictor on context switches
Commit 06c23f5ffe7ad45b908d0fff604dae08a7e334b9 upstream.

Required manual merge of arch/arm/mm/proc-v7.S.

Harden the branch predictor against Spectre v2 attacks on context
switches for ARMv7 and later CPUs.  We do this by:

Cortex A9, A12, A17, A73, A75: invalidating the BTB.
Cortex A15, Brahma B15: invalidating the instruction cache.

Cortex A57 and Cortex A72 are not addressed in this patch.

Cortex R7 and Cortex R8 are also not addressed as we do not enforce
memory protection on these cores.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
c0f64070a3 ARM: spectre: add Kconfig symbol for CPUs vulnerable to Spectre
Commit c58d237d0852a57fde9bc2c310972e8f4e3d155d upstream.

Add a Kconfig symbol for CPUs which are vulnerable to the Spectre
attacks.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
0d5360ee15 ARM: bugs: add support for per-processor bug checking
Commit 9d3a04925deeabb97c8e26d940b501a2873e8af3 upstream.

Add support for per-processor bug checking - each processor function
descriptor gains a function pointer for this check, which must not be
an __init function.  If non-NULL, this will be called whenever a CPU
enters the kernel via which ever path (boot CPU, secondary CPU startup,
CPU resuming, etc.)

This allows processor specific bug checks to validate that workaround
bits are properly enabled by firmware via all entry paths to the kernel.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
c7825c277b ARM: bugs: hook processor bug checking into SMP and suspend paths
Commit 26602161b5ba795928a5a719fe1d5d9f2ab5c3ef upstream.

Check for CPU bugs when secondary processors are being brought online,
and also when CPUs are resuming from a low power mode.  This gives an
opportunity to check that processor specific bug workarounds are
correctly enabled for all paths that a CPU re-enters the kernel.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
9a42b70744 ARM: bugs: prepare processor bug infrastructure
Commit a5b9177f69329314721aa7022b7e69dab23fa1f0 upstream.

Prepare the processor bug infrastructure so that it can be expanded to
check for per-processor bugs.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:26 +02:00
Russell King
1789de3354 ARM: add more CPU part numbers for Cortex and Brahma B15 CPUs
Commit f5683e76f35b4ec5891031b6a29036efe0a1ff84 upstream.

Add CPU part numbers for Cortex A53, A57, A72, A73, A75 and the
Broadcom Brahma B15 CPU.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:25 +02:00
Roman Gushchin
d62b8ac8cd mm: don't show nr_indirectly_reclaimable in /proc/vmstat
commit 7aaf7727235870f497eb928f728f7773d6df3b40 upstream.

Don't show nr_indirectly_reclaimable in /proc/vmstat, because there is
no need to export this vm counter to userspace, and some changes are
expected in reclaimable object accounting, which can alter this counter.

Link: http://lkml.kernel.org/r/20180425191422.9159-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:25 +02:00
Roman Gushchin
5de69d648a mm: treat indirectly reclaimable memory as free in overcommit logic
commit d79f7aa496fc94d763f67b833a1f36f4c171176f upstream.

Indirectly reclaimable memory can consume a significant part of total
memory and it's actually reclaimable (it will be released under actual
memory pressure).

So, the overcommit logic should treat it as free.

Otherwise, it's possible to cause random system-wide memory allocation
failures by consuming a significant amount of memory by indirectly
reclaimable memory, e.g.  dentry external names.

If overcommit policy GUESS is used, it might be used for denial of
service attack under some conditions.

The following program illustrates the approach.  It causes the kernel to
allocate an unreclaimable kmalloc-256 chunk for each stat() call, so
that at some point the overcommit logic may start blocking large
allocation system-wide.

  int main()
  {
  	char buf[256];
  	unsigned long i;
  	struct stat statbuf;

  	buf[0] = '/';
  	for (i = 1; i < sizeof(buf); i++)
  		buf[i] = '_';

  	for (i = 0; 1; i++) {
  		sprintf(&buf[248], "%8lu", i);
  		stat(buf, &statbuf);
  	}

  	return 0;
  }

This patch in combination with related indirectly reclaimable memory
patches closes this issue.

Link: http://lkml.kernel.org/r/20180313130041.8078-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
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>
2018-10-18 09:16:25 +02:00
Roman Gushchin
6d7942377c dcache: account external names as indirectly reclaimable memory
commit f1782c9bc547754f4bd3043fe8cfda53db85f13f upstream.

I received a report about suspicious growth of unreclaimable slabs on
some machines.  I've found that it happens on machines with low memory
pressure, and these unreclaimable slabs are external names attached to
dentries.

External names are allocated using generic kmalloc() function, so they
are accounted as unreclaimable.  But they are held by dentries, which
are reclaimable, and they will be reclaimed under the memory pressure.

In particular, this breaks MemAvailable calculation, as it doesn't take
unreclaimable slabs into account.  This leads to a silly situation, when
a machine is almost idle, has no memory pressure and therefore has a big
dentry cache.  And the resulting MemAvailable is too low to start a new
workload.

To address the issue, the NR_INDIRECTLY_RECLAIMABLE_BYTES counter is
used to track the amount of memory, consumed by external names.  The
counter is increased in the dentry allocation path, if an external name
structure is allocated; and it's decreased in the dentry freeing path.

To reproduce the problem I've used the following Python script:

  import os

  for iter in range (0, 10000000):
      try:
          name = ("/some_long_name_%d" % iter) + "_" * 220
          os.stat(name)
      except Exception:
          pass

Without this patch:
  $ cat /proc/meminfo | grep MemAvailable
  MemAvailable:    7811688 kB
  $ python indirect.py
  $ cat /proc/meminfo | grep MemAvailable
  MemAvailable:    2753052 kB

With the patch:
  $ cat /proc/meminfo | grep MemAvailable
  MemAvailable:    7809516 kB
  $ python indirect.py
  $ cat /proc/meminfo | grep MemAvailable
  MemAvailable:    7749144 kB

[guro@fb.com: fix indirectly reclaimable memory accounting for CONFIG_SLOB]
  Link: http://lkml.kernel.org/r/20180312194140.19517-1-guro@fb.com
[guro@fb.com: fix indirectly reclaimable memory accounting]
  Link: http://lkml.kernel.org/r/20180313125701.7955-1-guro@fb.com
Link: http://lkml.kernel.org/r/20180305133743.12746-5-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
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>
2018-10-18 09:16:25 +02:00
Roman Gushchin
dc09a5b68d mm: treat indirectly reclaimable memory as available in MemAvailable
commit 034ebf65c3c21d85b963d39f992258a64a85e3a9 upstream.

Adjust /proc/meminfo MemAvailable calculation by adding the amount of
indirectly reclaimable memory (rounded to the PAGE_SIZE).

Link: http://lkml.kernel.org/r/20180305133743.12746-4-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
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>
2018-10-18 09:16:25 +02:00
Roman Gushchin
c605894c84 mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES
commit eb59254608bc1d42c4c6afdcdce9c0d3ce02b318 upstream.

Patch series "indirectly reclaimable memory", v2.

This patchset introduces the concept of indirectly reclaimable memory
and applies it to fix the issue of when a big number of dentries with
external names can significantly affect the MemAvailable value.

This patch (of 3):

Introduce a concept of indirectly reclaimable memory and adds the
corresponding memory counter and /proc/vmstat item.

Indirectly reclaimable memory is any sort of memory, used by the kernel
(except of reclaimable slabs), which is actually reclaimable, i.e.  will
be released under memory pressure.

The counter is in bytes, as it's not always possible to count such
objects in pages.  The name contains BYTES by analogy to
NR_KERNEL_STACK_KB.

Link: http://lkml.kernel.org/r/20180305133743.12746-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
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>
2018-10-18 09:16:25 +02:00
Mathias Nyman
7a4f9efdb2 xhci: Don't print a warning when setting link state for disabled ports
commit 1208d8a84fdcae6b395c57911cdf907450d30e70 upstream.

When disabling a USB3 port the hub driver will set the port link state to
U3 to prevent "ejected" or "safely removed" devices that are still
physically connected from immediately re-enumerating.

If the device was really unplugged, then error messages were printed
as the hub tries to set the U3 link state for a port that is no longer
enabled.

xhci-hcd ee000000.usb: Cannot set link state.
usb usb8-port1: cannot disable (err = -32)

Don't print error message in xhci-hub if hub tries to set port link state
for a disabled port. Return -ENODEV instead which also silences hub driver.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:25 +02:00
Edgar Cherkasov
74a960430a i2c: i2c-scmi: fix for i2c_smbus_write_block_data
commit 08d9db00fe0e300d6df976e6c294f974988226dd upstream.

The i2c-scmi driver crashes when the SMBus Write Block transaction is
executed:

WARNING: CPU: 9 PID: 2194 at mm/page_alloc.c:3931 __alloc_pages_slowpath+0x9db/0xec0
 Call Trace:
  ? get_page_from_freelist+0x49d/0x11f0
  ? alloc_pages_current+0x6a/0xe0
  ? new_slab+0x499/0x690
  __alloc_pages_nodemask+0x265/0x280
  alloc_pages_current+0x6a/0xe0
  kmalloc_order+0x18/0x40
  kmalloc_order_trace+0x24/0xb0
  ? acpi_ut_allocate_object_desc_dbg+0x62/0x10c
  __kmalloc+0x203/0x220
  acpi_os_allocate_zeroed+0x34/0x36
  acpi_ut_copy_eobject_to_iobject+0x266/0x31e
  acpi_evaluate_object+0x166/0x3b2
  acpi_smbus_cmi_access+0x144/0x530 [i2c_scmi]
  i2c_smbus_xfer+0xda/0x370
  i2cdev_ioctl_smbus+0x1bd/0x270
  i2cdev_ioctl+0xaa/0x250
  do_vfs_ioctl+0xa4/0x600
  SyS_ioctl+0x79/0x90
  do_syscall_64+0x73/0x130
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
ACPI Error: Evaluating _SBW: 4 (20170831/smbus_cmi-185)

This problem occurs because the length of ACPI Buffer object is not
defined/initialized in the code before a corresponding ACPI method is
called. The obvious patch below fixes this issue.

Signed-off-by: Edgar Cherkasov <echerkasov@dev.rtsoft.ru>
Acked-by: Viktor Krasnov <vkrasnov@dev.rtsoft.ru>
Acked-by: Michael Brunner <Michael.Brunner@kontron.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:25 +02:00
Jan Kara
1b7ff5208d mm: Preserve _PAGE_DEVMAP across mprotect() calls
commit 4628a64591e6cee181237060961e98c615c33966 upstream.

Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a
result we will see warnings such as:

BUG: Bad page map in process JobWrk0013  pte:800001803875ea25 pmd:7624381067
addr:00007f0930720000 vm_flags:280000f9 anon_vma:          (null) mapping:ffff97f2384056f0 index:0
file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage:          (null)
CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G        W          4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased)
Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
Call Trace:
 dump_stack+0x5a/0x75
 print_bad_pte+0x217/0x2c0
 ? enqueue_task_fair+0x76/0x9f0
 _vm_normal_page+0xe5/0x100
 zap_pte_range+0x148/0x740
 unmap_page_range+0x39a/0x4b0
 unmap_vmas+0x42/0x90
 unmap_region+0x99/0xf0
 ? vma_gap_callbacks_rotate+0x1a/0x20
 do_munmap+0x255/0x3a0
 vm_munmap+0x54/0x80
 SyS_munmap+0x1d/0x30
 do_syscall_64+0x74/0x150
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
...

when mprotect(2) gets used on DAX mappings. Also there is a wide variety
of other failures that can result from the missing _PAGE_DEVMAP flag
when the area gets used by get_user_pages() later.

Fix the problem by including _PAGE_DEVMAP in a set of flags that get
preserved by mprotect(2).

Fixes: 69660fd797c3 ("x86, mm: introduce _PAGE_DEVMAP")
Fixes: ebd31197931d ("powerpc/mm: Add devmap support for ppc64")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:25 +02:00
Jérôme Glisse
68ba0bdfe4 mm/thp: fix call to mmu_notifier in set_pmd_migration_entry() v2
commit bfba8e5cf28f413aa05571af493871d74438979f upstream.

Inside set_pmd_migration_entry() we are holding page table locks and thus
we can not sleep so we can not call invalidate_range_start/end()

So remove call to mmu_notifier_invalidate_range_start/end() because they
are call inside the function calling set_pmd_migration_entry() (see
try_to_unmap_one()).

Link: http://lkml.kernel.org/r/20181012181056.7864-1-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Zi Yan <zi.yan@cs.rutgers.edu>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Will Deacon
3e6275d940 arm64: perf: Reject stand-alone CHAIN events for PMUv3
commit ca2b497253ad01c80061a1f3ee9eb91b5d54a849 upstream.

It doesn't make sense for a perf event to be configured as a CHAIN event
in isolation, so extend the arm_pmu structure with a ->filter_match()
function to allow the backend PMU implementation to reject CHAIN events
early.

Cc: <stable@vger.kernel.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Marco Felsch
b3e4b3c70a pinctrl: mcp23s08: fix irq and irqchip setup order
commit f259f896f2348f0302f6f88d4382378cf9d23a7e upstream.

Since 'commit 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")' the
irq request isn't the last devm_* allocation. Without a deeper look at
the irq and testing this isn't a good solution. Since this driver relies
on the devm mechanism, requesting a interrupt should be the last thing
to avoid memory corruptions during unbinding.

'Commit 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")' fixed the
order for the interrupt-controller use case only. The
mcp23s08_irq_setup() must be split into two to fix it for the
interrupt-controller use case and to register the irq at last. So the
irq will be freed first during unbind.

Cc: stable@vger.kernel.org
Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Dmitry Mastykin <mastichi@gmail.com>
Cc: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Fixes: 82039d244f87 ("pinctrl: mcp23s08: add pinconf support")
Fixes: 02e389e63e35 ("pinctrl: mcp23s08: fix irq setup order")
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Tested-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Chris Boot
d5833a50c6 mmc: block: avoid multiblock reads for the last sector in SPI mode
commit 41591b38f5f8f78344954b68582b5f00e56ffe61 upstream.

On some SD cards over SPI, reading with the multiblock read command the last
sector will leave the card in a bad state.

Remove last sectors from the multiblock reading cmd.

Signed-off-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Tejun Heo
bc183079dd cgroup: Fix dom_cgrp propagation when enabling threaded mode
commit 479adb89a97b0a33e5a9d702119872cc82ca21aa upstream.

A cgroup which is already a threaded domain may be converted into a
threaded cgroup if the prerequisite conditions are met.  When this
happens, all threaded descendant should also have their ->dom_cgrp
updated to the new threaded domain cgroup.  Unfortunately, this
propagation was missing leading to the following failure.

  # cd /sys/fs/cgroup/unified
  # cat cgroup.subtree_control    # show that no controllers are enabled

  # mkdir -p mycgrp/a/b/c
  # echo threaded > mycgrp/a/b/cgroup.type

  At this point, the hierarchy looks as follows:

      mycgrp [d]
	  a [dt]
	      b [t]
		  c [inv]

  Now let's make node "a" threaded (and thus "mycgrp" s made "domain threaded"):

  # echo threaded > mycgrp/a/cgroup.type

  By this point, we now have a hierarchy that looks as follows:

      mycgrp [dt]
	  a [t]
	      b [t]
		  c [inv]

  But, when we try to convert the node "c" from "domain invalid" to
  "threaded", we get ENOTSUP on the write():

  # echo threaded > mycgrp/a/b/c/cgroup.type
  sh: echo: write error: Operation not supported

This patch fixes the problem by

* Moving the opencoded ->dom_cgrp save and restoration in
  cgroup_enable_threaded() into cgroup_{save|restore}_control() so
  that mulitple cgroups can be handled.

* Updating all threaded descendants' ->dom_cgrp to point to the new
  dom_cgrp when enabling threaded mode.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Reported-by: Amin Jamali <ajamali@pivotal.io>
Reported-by: Joao De Almeida Pereira <jpereira@pivotal.io>
Link: https://lore.kernel.org/r/CAKgNAkhHYCMn74TCNiMJ=ccLd7DcmXSbvw3CbZ1YREeG7iJM5g@mail.gmail.com
Fixes: 454000adaa2a ("cgroup: introduce cgroup->dom_cgrp and threaded css_set handling")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Damien Le Moal
c339fab172 dm linear: fix linear_end_io conditional definition
commit 118aa47c7072bce05fc39bd40a1c0a90caed72ab upstream.

The dm-linear target is independent of the dm-zoned target. For code
requiring support for zoned block devices, use CONFIG_BLK_DEV_ZONED
instead of CONFIG_DM_ZONED.

While at it, similarly to dm linear, also enable the DM_TARGET_ZONED_HM
feature in dm-flakey only if CONFIG_BLK_DEV_ZONED is defined.

Fixes: beb9caac211c1 ("dm linear: eliminate linear_end_io call if CONFIG_DM_ZONED disabled")
Fixes: 0be12c1c7fce7 ("dm linear: add support for zoned block devices")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Mike Snitzer
efd6537984 dm linear: eliminate linear_end_io call if CONFIG_DM_ZONED disabled
commit beb9caac211c1be1bc118bb62d5cf09c4107e6a5 upstream.

It is best to avoid any extra overhead associated with bio completion.
DM core will indirectly call a DM target's .end_io if it is defined.
In the case of DM linear, there is no need to do so (for every bio that
completes) if CONFIG_DM_ZONED is not enabled.

Avoiding an extra indirect call for every bio completion is very
important for ensuring DM linear doesn't incur more overhead that
further widens the performance gap between dm-linear and raw block
devices.

Fixes: 0be12c1c7fce7 ("dm linear: add support for zoned block devices")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Damien Le Moal
261f2cba10 dm: fix report zone remapping to account for partition offset
commit 9864cd5dc54cade89fd4b0954c2e522841aa247c upstream.

If dm-linear or dm-flakey are layered on top of a partition of a zoned
block device, remapping of the start sector and write pointer position
of the zones reported by a report zones BIO must be modified to account
for the target table entry mapping (start offset within the device and
entry mapping with the dm device).  If the target's backing device is a
partition of a whole disk, the start sector on the physical device of
the partition must also be accounted for when modifying the zone
information.  However, dm_remap_zone_report() was not considering this
last case, resulting in incorrect zone information remapping with
targets using disk partitions.

Fix this by calculating the target backing device start sector using
the position of the completed report zones BIO and the unchanged
position and size of the original report zone BIO. With this value
calculated, the start sector and write pointer position of the target
zones can be correctly remapped.

Fixes: 10999307c14e ("dm: introduce dm_remap_zone_report()")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Shenghui Wang
6c8faa19e9 dm cache: destroy migration_cache if cache target registration failed
commit c7cd55504a5b0fc826a2cd9540845979d24ae542 upstream.

Commit 7e6358d244e47 ("dm: fix various targets to dm_register_target
after module __init resources created") inadvertently introduced this
bug when it moved dm_register_target() after the call to KMEM_CACHE().

Fixes: 7e6358d244e47 ("dm: fix various targets to dm_register_target after module __init resources created")
Cc: stable@vger.kernel.org
Signed-off-by: Shenghui Wang <shhuiw@foxmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:24 +02:00
Eric Farman
8d2f62cb2d s390/cio: Fix how vfio-ccw checks pinned pages
commit 24abf2901b18bf941b9f21ea2ce5791f61097ae4 upstream.

We have two nested loops to check the entries within the pfn_array_table
arrays.  But we mistakenly use the outer array as an index in our check,
and completely ignore the indexing performed by the inner loop.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20181002010235.42483-1-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:23 +02:00