712800 Commits

Author SHA1 Message Date
Geert Uytterhoeven
ddca5c776f ARM: OMAP1: clock: Fix debugfs_create_*() usage
[ Upstream commit 8cbbf1745dcde7ba7e423dc70619d223de90fd43 ]

When exposing data access through debugfs, the correct
debugfs_create_*() functions must be used, depending on data type.

Remove all casts from data pointers passed to debugfs_create_*()
functions, as such casts prevent the compiler from flagging bugs.

Correct all wrong usage:
  - clk.rate is unsigned long, not u32,
  - clk.flags is u8, not u32, which exposed the successive
    clk.rate_offset and clk.src_offset fields.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:55 +02:00
Tony Lindgren
d615dddc6e ARM: OMAP2+: Fix sar_base inititalization for HS omaps
[ Upstream commit fe27f16794f313f5fc16f6d2f42d8c2b2f4d70cc ]

HS omaps use irq_save_secure_context() instead of irq_save_context()
so sar_base will never get initialized and irq_sar_clear() gets called
with a wrong address for HS omaps from irq_restore_context().

Starting with commit f4b9f40ae95b ("ARM: OMAP4+: Initialize SAR RAM
base early for proper CPU1 reset for kexec") we have it available,
and this ideally would been fixed with that commit already.

Fixes: f4b9f40ae95b ("ARM: OMAP4+: Initialize SAR RAM base early for
proper CPU1 reset for kexec")
Cc: Andrew F. Davis <afd@ti.com>
Cc: Dave Gerlach <d-gerlach@ti.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Santosh Shilimkar <ssantosh@kernel.org>
Cc: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:55 +02:00
Tony Lindgren
c22e3886fc ARM: OMAP3: Fix prm wake interrupt for resume
[ Upstream commit d3be6d2a08bd26580562d9714d3d97ea9ba22c73 ]

For platform_suspend_ops, the finish call is too late to re-enable wake
irqs and we need re-enable wake irqs on wake call instead.

Otherwise noirq resume for devices has already happened. And then
dev_pm_disarm_wake_irq() has already disabled the dedicated wake irqs
when the interrupt triggers and the wake irq is never handled.

For devices that are already in PM runtime suspended state when we
enter suspend this means that a possible wake irq will never trigger.

And this can lead into a situation where a device has a pending padconf
wake irq, and the device will stay unresponsive to any further wake
irqs.

This issue can be easily reproduced by setting serial console log level
to zero, letting the serial console idle, and suspend the system from
an ssh terminal. Then try to wake up the system by typing to the serial
console.

Note that this affects only omap3 PRM interrupt as that's currently
the only omap variant that does anything in omap_pm_wake().

In general, for the wake irqs to work, the interrupt must have either
IRQF_NO_SUSPEND or IRQF_EARLY_RESUME set for it to trigger before
dev_pm_disarm_wake_irq() disables the wake irqs.

Reported-by: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:55 +02:00
Qi Hou
7ffe100ce6 ARM: OMAP2+: timer: fix a kmemleak caused in omap_get_timer_dt
[ Upstream commit db35340c536f1af0108ec9a0b2126a05d358d14a ]

When more than one GP timers are used as kernel system timers and the
corresponding nodes in device-tree are marked with the same "disabled"
property, then the "attr" field of the property will be initialized
more than once as the property being added to sys file system via
__of_add_property_sysfs().

In __of_add_property_sysfs(), the "name" field of pp->attr.attr is set
directly to the return value of safe_name(), without taking care of
whether it's already a valid pointer to a memory block. If it is, its
old value will always be overwritten by the new one and the memory block
allocated before will a "ghost", then a kmemleak happened.

That the same "disabled" property being added to different nodes of device
tree would cause that kind of kmemleak overhead, at least once.

To fix it, allocate the property dynamically, and delete static one.

Signed-off-by: Qi Hou <qi.hou@windriver.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:55 +02:00
Anders Roxell
b2f5d98f33 selftests: memfd: add config fragment for fuse
[ Upstream commit 9a606f8d55cfc932ec02172aaed4124fdc150047 ]

The memfd test requires to insert the fuse module (CONFIG_FUSE_FS).

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:55 +02:00
Naresh Kamboju
b9ddf39dd5 selftests: pstore: Adding config fragment CONFIG_PSTORE_RAM=m
[ Upstream commit 9a379e77033f02c4a071891afdf0f0a01eff8ccb ]

pstore_tests and pstore_post_reboot_tests need CONFIG_PSTORE_RAM=m

Signed-off-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:55 +02:00
Dominik Brodowski
a666ad4bbc selftest/vDSO: fix O=
[ Upstream commit 70b574e7d719bdf96d26528cb289f3e782e83979 ]

The vDSO selftests ignored the O= or KBUILD_OUTPUT= parameters. Fix it.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:55 +02:00
Anders Roxell
198e26a0ef selftests: sync: missing CFLAGS while compiling
[ Upstream commit b2c93e300a11b419b4c67ce08e16fa1436d8118c ]

Based on patch: https://patchwork.kernel.org/patch/10042045/

arch64-linux-gnu-gcc -c sync.c -o sync/sync.o
sync.c:42:29: fatal error: linux/sync_file.h: No such file or directory
 #include <linux/sync_file.h>
                             ^
CFLAGS is not used during the compile step, so the system instead of
kernel headers are used.  Fix this by adding CFLAGS to the OBJS compile
rule.

Reported-by: Lei Yang <Lei.Yang@windriver.com>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
Dong Bo
4adc95c5a0 libata: Fix compile warning with ATA_DEBUG enabled
[ Upstream commit 0d3e45bc6507bd1f8728bf586ebd16c2d9e40613 ]

This fixs the following comile warnings with ATA_DEBUG enabled,
which detected by Linaro GCC 5.2-2015.11:

  drivers/ata/libata-scsi.c: In function 'ata_scsi_dump_cdb':
  ./include/linux/kern_levels.h:5:18: warning: format '%d' expects
  argument of type 'int', but argument 6 has type 'u64 {aka long
   long unsigned int}' [-Wformat=]

tj: Patch hand-applied and description trimmed.

Signed-off-by: Dong Bo <dongbo4@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
Shawn Lin
afe088b034 arm64: dts: rockchip: correct ep-gpios for rk3399-sapphire
[ Upstream commit 2b7d2ed1af2e2c0c90a1a8b97926b7b6c6cb03ed ]

The endpoint control gpio for rk3399-sapphire boards is gpio2_a4,
so correct it now.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
Kamil Trzciński
fa4cf9010e arm64: dts: rockchip: fix rock64 gmac2io stability issues
[ Upstream commit 73e42e18669934fa96cf2bb54291da54177076d7 ]

This commit enables thresh dma mode as this forces to disable checksuming,
and chooses delay values which make the interface stable.

These changes are needed, because ROCK64 is faced with two problems:
1. tx checksuming does not work with packets larger than 1498,
2. the default delays for tx/rx are not stable when using 1Gbps connection.

Delays were found out with:
https://github.com/ayufan-rock64/linux-build/tree/master/recipes/gmac-delays-test

Signed-off-by: Kamil Trzciński <ayufan@ayufan.eu>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
Jason Wang
6fc72fd156 ptr_ring: prevent integer overflow when calculating size
[ Upstream commit 54e02162d4454a99227f520948bf4494c3d972d0 ]

Switch to use dividing to prevent integer overflow when size is too
big to calculate allocation size properly.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Fixes: 6e6e41c31122 ("ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
Ulf Magnusson
052eb2d6dc ARC: Fix malformed ARC_EMUL_UNALIGNED default
[ Upstream commit 827cc2fa024dd6517d62de7a44c7b42f32af371b ]

'default N' should be 'default n', though they happen to have the same
effect here, due to undefined symbols (N in this case) evaluating to n
in a tristate sense.

Remove the default from ARC_EMUL_UNALIGNED instead of changing it. bool
and tristate symbols implicitly default to n.

Discovered with the
https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_ulfalizer_Kconfiglib_blob_master_examples_list-5Fundefined.py&d=DwIBAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=c14YS-cH-kdhTOW89KozFhBtBJgs1zXscZojEZQ0THs&m=WxxD8ozR7QQUVzNCBksiznaisBGO_crN7PBOvAoju8s&s=1LmxsNqxwT-7wcInVpZ6Z1J27duZKSoyKxHIJclXU_M&e=
script.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
Peter Oh
0f097096b7 mac80211: mesh: fix wrong mesh TTL offset calculation
[ Upstream commit c4de37ee2b55deac7d6aeac33e02e3d6be243898 ]

mesh TTL offset in Mesh Channel Switch Parameters element depends on
not only Secondary Channel Offset element, but also affected by
HT Control field and Wide Bandwidth Channel Switch element.
So use element structure to manipulate mesh channel swich param IE
after removing its constant attribution to correct the miscalculation.

Signed-off-by: Peter Oh <peter.oh@bowerswilkins.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
James Hogan
49e3075217 MIPS: generic: Fix machine compatible matching
[ Upstream commit 9a9ab3078e2744a1a55163cfaec73a5798aae33e ]

We now have a platform (Ranchu) in the "generic" platform which matches
based on the FDT compatible string using mips_machine_is_compatible(),
however that function doesn't stop at a blank struct
of_device_id::compatible as that is an array in the struct, not a
pointer to a string.

Fix the loop completion to check the first byte of the compatible array
rather than the address of the compatible array in the struct.

Fixes: eed0eabd12ef ("MIPS: generic: Introduce generic DT-based board support")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Reviewed-by: Matt Redfearn <matt.redfearn@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18580/
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
Nicholas Piggin
3084902aa9 powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit
commit a048a07d7f4535baa4cbad6bc024f175317ab938 upstream.

On some CPUs we can prevent a vulnerability related to store-to-load
forwarding by preventing store forwarding between privilege domains,
by inserting a barrier in kernel entry and exit paths.

This is known to be the case on at least Power7, Power8 and Power9
powerpc CPUs.

Barriers must be inserted generally before the first load after moving
to a higher privilege, and after the last store before moving to a
lower privilege, HV and PR privilege transitions must be protected.

Barriers are added as patch sections, with all kernel/hypervisor entry
points patched, and the exit points to lower privilge levels patched
similarly to the RFI flush patching.

Firmware advertisement is not implemented yet, so CPU flush types
are hard coded.

Thanks to Michal Suchánek for bug fixes and review.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:54 +02:00
Michael Ellerman
b90a6bddc8 powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()
commit 501a78cbc17c329fabf8e9750a1e9ab810c88a0e upstream.

The recent LPM changes to setup_rfi_flush() are causing some section
mismatch warnings because we removed the __init annotation on
setup_rfi_flush():

  The function setup_rfi_flush() references
  the function __init ppc64_bolted_size().
  the function __init memblock_alloc_base().

The references are actually in init_fallback_flush(), but that is
inlined into setup_rfi_flush().

These references are safe because:
 - only pseries calls setup_rfi_flush() at runtime
 - pseries always passes L1D_FLUSH_FALLBACK at boot
 - so the fallback flush area will always be allocated
 - so the check in init_fallback_flush() will always return early:
   /* Only allocate the fallback flush area once (at boot time). */
   if (l1d_flush_fallback_area)
   	return;

 - and therefore we won't actually call the freed init routines.

We should rework the code to make it safer by default rather than
relying on the above, but for now as a quick-fix just add a __ref
annotation to squash the warning.

Fixes: abf110f3e1ce ("powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:53 +02:00
Mauricio Faria de Oliveira
1618f211f9 powerpc/pseries: Restore default security feature flags on setup
commit 6232774f1599028a15418179d17f7df47ede770a upstream.

After migration the security feature flags might have changed (e.g.,
destination system with unpatched firmware), but some flags are not
set/clear again in init_cpu_char_feature_flags() because it assumes
the security flags to be the defaults.

Additionally, if the H_GET_CPU_CHARACTERISTICS hypercall fails then
init_cpu_char_feature_flags() does not run again, which potentially
might leave the system in an insecure or sub-optimal configuration.

So, just restore the security feature flags to the defaults assumed
by init_cpu_char_feature_flags() so it can set/clear them correctly,
and to ensure safe settings are in place in case the hypercall fail.

Fixes: f636c14790ea ("powerpc/pseries: Set or clear security feature flags")
Depends-on: 19887d6a28e2 ("powerpc: Move default security feature flags")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:53 +02:00
Mauricio Faria de Oliveira
f092a18012 powerpc: Move default security feature flags
commit e7347a86830f38dc3e40c8f7e28c04412b12a2e7 upstream.

This moves the definition of the default security feature flags
(i.e., enabled by default) closer to the security feature flags.

This can be used to restore current flags to the default flags.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:53 +02:00
Mauricio Faria de Oliveira
a28ff26d5e powerpc/pseries: Fix clearing of security feature flags
commit 0f9bdfe3c77091e8704d2e510eb7c2c2c6cde524 upstream.

The H_CPU_BEHAV_* flags should be checked for in the 'behaviour' field
of 'struct h_cpu_char_result' -- 'character' is for H_CPU_CHAR_*
flags.

Found by playing around with QEMU's implementation of the hypercall:

  H_CPU_CHAR=0xf000000000000000
  H_CPU_BEHAV=0x0000000000000000

  This clears H_CPU_BEHAV_FAVOUR_SECURITY and H_CPU_BEHAV_L1D_FLUSH_PR
  so pseries_setup_rfi_flush() disables 'rfi_flush'; and it also
  clears H_CPU_CHAR_L1D_THREAD_PRIV flag. So there is no RFI flush
  mitigation at all for cpu_show_meltdown() to report; but currently
  it does:

  Original kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/meltdown
    Mitigation: RFI Flush

  Patched kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/meltdown
    Not affected

  H_CPU_CHAR=0x0000000000000000
  H_CPU_BEHAV=0xf000000000000000

  This sets H_CPU_BEHAV_BNDS_CHK_SPEC_BAR so cpu_show_spectre_v1() should
  report vulnerable; but currently it doesn't:

  Original kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1
    Not affected

  Patched kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1
    Vulnerable

Brown-paper-bag-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: f636c14790ea ("powerpc/pseries: Set or clear security feature flags")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:53 +02:00
Michael Ellerman
046e9adae4 powerpc/64s: Wire up cpu_show_spectre_v2()
commit d6fbe1c55c55c6937cbea3531af7da84ab7473c3 upstream.

Add a definition for cpu_show_spectre_v2() to override the generic
version. This has several permuations, though in practice some may not
occur we cater for any combination.

The most verbose is:

  Mitigation: Indirect branch serialisation (kernel only), Indirect
  branch cache disabled, ori31 speculation barrier enabled

We don't treat the ori31 speculation barrier as a mitigation on its
own, because it has to be *used* by code in order to be a mitigation
and we don't know if userspace is doing that. So if that's all we see
we say:

  Vulnerable, ori31 speculation barrier enabled

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:53 +02:00
Michael Ellerman
6e77feadbf powerpc/64s: Wire up cpu_show_spectre_v1()
commit 56986016cb8cd9050e601831fe89f332b4e3c46e upstream.

Add a definition for cpu_show_spectre_v1() to override the generic
version. Currently this just prints "Not affected" or "Vulnerable"
based on the firmware flag.

Although the kernel does have array_index_nospec() in a few places, we
haven't yet audited all the powerpc code to see where it's necessary,
so for now we don't list that as a mitigation.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:53 +02:00
Michael Ellerman
7a62b0f648 powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()
commit 2e4a16161fcd324b1f9bf6cb6856529f7eaf0689 upstream.

Now that we have the security flags we can simplify the code in
pseries_setup_rfi_flush() because the security flags have pessimistic
defaults.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:52 +02:00
Michael Ellerman
3bf1695bbb powerpc/powernv: Use the security flags in pnv_setup_rfi_flush()
commit 37c0bdd00d3ae83369ab60a6712c28e11e6458d5 upstream.

Now that we have the security flags we can significantly simplify the
code in pnv_setup_rfi_flush(), because we can use the flags instead of
checking device tree properties and because the security flags have
pessimistic defaults.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:52 +02:00
Michael Ellerman
d71a3e0a2d powerpc/64s: Enhance the information in cpu_show_meltdown()
commit ff348355e9c72493947be337bb4fae4fc1a41eba upstream.

Now that we have the security feature flags we can make the
information displayed in the "meltdown" file more informative.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:52 +02:00
Michael Ellerman
ae8afdf604 powerpc/64s: Move cpu_show_meltdown()
commit 8ad33041563a10b34988800c682ada14b2612533 upstream.

This landed in setup_64.c for no good reason other than we had nowhere
else to put it. Now that we have a security-related file, that is a
better place for it so move it.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:52 +02:00
Michael Ellerman
f2fdeebd85 powerpc/powernv: Set or clear security feature flags
commit 77addf6e95c8689e478d607176b399a6242a777e upstream.

Now that we have feature flags for security related things, set or
clear them based on what we see in the device tree provided by
firmware.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:52 +02:00
Michael Ellerman
9ba774cc0f powerpc/pseries: Set or clear security feature flags
commit f636c14790ead6cc22cf62279b1f8d7e11a67116 upstream.

Now that we have feature flags for security related things, set or
clear them based on what we receive from the hypercall.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:52 +02:00
Michael Ellerman
e2ba26dba5 powerpc: Add security feature flags for Spectre/Meltdown
commit 9a868f634349e62922c226834aa23e3d1329ae7f upstream.

This commit adds security feature flags to reflect the settings we
receive from firmware regarding Spectre/Meltdown mitigations.

The feature names reflect the names we are given by firmware on bare
metal machines. See the hostboot source for details.

Arguably these could be firmware features, but that then requires them
to be read early in boot so they're available prior to asm feature
patching, but we don't actually want to use them for patching. We may
also want to dynamically update them in future, which would be
incompatible with the way firmware features work (at the moment at
least). So for now just make them separate flags.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Michael Ellerman
4c5463a5a3 powerpc/pseries: Add new H_GET_CPU_CHARACTERISTICS flags
commit c4bc36628d7f8b664657d8bd6ad1c44c177880b7 upstream.

Add some additional values which have been defined for the
H_GET_CPU_CHARACTERISTICS hypercall.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Michael Ellerman
d1cb5ff450 powerpc/rfi-flush: Call setup_rfi_flush() after LPM migration
commit 921bc6cf807ceb2ab8005319cf39f33494d6b100 upstream.

We might have migrated to a machine that uses a different flush type,
or doesn't need flushing at all.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Mauricio Faria de Oliveira
123f6d5cca powerpc/rfi-flush: Differentiate enabled and patched flush types
commit 0063d61ccfc011f379a31acaeba6de7c926fed2c upstream.

Currently the rfi-flush messages print 'Using <type> flush' for all
enabled_flush_types, but that is not necessarily true -- as now the
fallback flush is always enabled on pseries, but the fixup function
overwrites its nop/branch slot with other flush types, if available.

So, replace the 'Using <type> flush' messages with '<type> flush is
available'.

Also, print the patched flush types in the fixup function, so users
can know what is (not) being used (e.g., the slower, fallback flush,
or no flush type at all if flush is disabled via the debugfs switch).

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Michael Ellerman
6af06dcdea powerpc/rfi-flush: Always enable fallback flush on pseries
commit 84749a58b6e382f109abf1e734bc4dd43c2c25bb upstream.

This ensures the fallback flush area is always allocated on pseries,
so in case a LPAR is migrated from a patched to an unpatched system,
it is possible to enable the fallback flush in the target system.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Michael Ellerman
d744f8457f powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again
commit abf110f3e1cea40f5ea15e85f5d67c39c14568a7 upstream.

For PowerVM migration we want to be able to call setup_rfi_flush()
again after we've migrated the partition.

To support that we need to check that we're not trying to allocate the
fallback flush area after memblock has gone away (i.e., boot-time only).

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Michael Ellerman
5412a9d91d powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs code
commit 1e2a9fc7496955faacbbed49461d611b704a7505 upstream.

rfi_flush_enable() includes a check to see if we're already
enabled (or disabled), and in that case does nothing.

But that means calling setup_rfi_flush() a 2nd time doesn't actually
work, which is a bit confusing.

Move that check into the debugfs code, where it really belongs.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Michael Ellerman
bf434b31ba powerpc/powernv: Support firmware disable of RFI flush
commit eb0a2d2620ae431c543963c8c7f08f597366fc60 upstream.

Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.

Fixes: 6e032b350cd1 ("powerpc/powernv: Check device-tree for RFI flush settings")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Michael Ellerman
dff1a7e6c3 powerpc/pseries: Support firmware disable of RFI flush
commit 582605a429e20ae68fd0b041b2e840af296edd08 upstream.

Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.

Fixes: 8989d56878a7 ("powerpc/pseries: Query hypervisor for RFI flush settings")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:51 +02:00
Nicholas Piggin
2245d95d9f powerpc/64s: Improve RFI L1-D cache flush fallback
commit bdcb1aefc5b3f7d0f1dc8b02673602bca2ff7a4b upstream.

The fallback RFI flush is used when firmware does not provide a way
to flush the cache. It's a "displacement flush" that evicts useful
data by displacing it with an uninteresting buffer.

The flush has to take care to work with implementation specific cache
replacment policies, so the recipe has been in flux. The initial
slow but conservative approach is to touch all lines of a congruence
class, with dependencies between each load. It has since been
determined that a linear pattern of loads without dependencies is
sufficient, and is significantly faster.

Measuring the speed of a null syscall with RFI fallback flush enabled
gives the relative improvement:

P8 - 1.83x
P9 - 1.75x

The flush also becomes simpler and more adaptable to different cache
geometries.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:50 +02:00
David Vrabel
421e1fadb0 x86/kvm: fix LAPIC timer drift when guest uses periodic mode
commit d8f2f498d9ed0c5010bc1bbc1146f94c8bf9f8cc upstream.

Since 4.10, commit 8003c9ae204e (KVM: LAPIC: add APIC Timer
periodic/oneshot mode VMX preemption timer support), guests using
periodic LAPIC timers (such as FreeBSD 8.4) would see their timers
drift significantly over time.

Differences in the underlying clocks and numerical errors means the
periods of the two timers (hv and sw) are not the same. This
difference will accumulate with every expiry resulting in a large
error between the hv and sw timer.

This means the sw timer may be running slow when compared to the hv
timer. When the timer is switched from hv to sw, the now active sw
timer will expire late. The guest VCPU is reentered and it switches to
using the hv timer. This timer catches up, injecting multiple IRQs
into the guest (of which the guest only sees one as it does not get to
run until the hv timer has caught up) and thus the guest's timer rate
is low (and becomes increasing slower over time as the sw timer lags
further and further behind).

I believe a similar problem would occur if the hv timer is the slower
one, but I have not observed this.

Fix this by synchronizing the deadlines for both timers to the same
time source on every tick. This prevents the errors from accumulating.

Fixes: 8003c9ae204e21204e49816c5ea629357e283b06
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: David Vrabel <david.vrabel@nutanix.com>
Cc: stable@vger.kernel.org
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:50 +02:00
Jim Mattson
b3ce16455c kvm: x86: IA32_ARCH_CAPABILITIES is always supported
commit 1eaafe91a0df4157521b6417b3dd8430bf5f52f0 upstream.

If there is a possibility that a VM may migrate to a Skylake host,
then the hypervisor should report IA32_ARCH_CAPABILITIES.RSBA[bit 2]
as being set (future work, of course). This implies that
CPUID.(EAX=7,ECX=0):EDX.ARCH_CAPABILITIES[bit 29] should be
set. Therefore, kvm should report this CPUID bit as being supported
whether or not the host supports it.  Userspace is still free to clear
the bit if it chooses.

For more information on RSBA, see Intel's white paper, "Retpoline: A
Branch Target Injection Mitigation" (Document Number 337131-001),
currently available at https://bugzilla.kernel.org/show_bug.cgi?id=199511.

Since the IA32_ARCH_CAPABILITIES MSR is emulated in kvm, there is no
dependency on hardware support for this feature.

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Fixes: 28c1c9fabf48 ("KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES")
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:50 +02:00
Wei Huang
e765fd97e0 KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed
commit c4d2188206bafa177ea58e9a25b952baa0bf7712 upstream.

The CPUID bits of OSXSAVE (function=0x1) and OSPKE (func=0x7, leaf=0x0)
allows user apps to detect if OS has set CR4.OSXSAVE or CR4.PKE. KVM is
supposed to update these CPUID bits when CR4 is updated. Current KVM
code doesn't handle some special cases when updates come from emulator.
Here is one example:

  Step 1: guest boots
  Step 2: guest OS enables XSAVE ==> CR4.OSXSAVE=1 and CPUID.OSXSAVE=1
  Step 3: guest hot reboot ==> QEMU reset CR4 to 0, but CPUID.OSXAVE==1
  Step 4: guest os checks CPUID.OSXAVE, detects 1, then executes xgetbv

Step 4 above will cause an #UD and guest crash because guest OS hasn't
turned on OSXAVE yet. This patch solves the problem by comparing the the
old_cr4 with cr4. If the related bits have been changed,
kvm_update_cpuid() needs to be called.

Signed-off-by: Wei Huang <wei@redhat.com>
Reviewed-by: Bandan Das <bsd@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:50 +02:00
David Hildenbrand
16c463a4ec KVM: s390: vsie: fix < 8k check for the itdba
commit f4a551b72358facbbe5714248dff78404272feee upstream.

By missing an "L", we might detect some addresses to be <8k,
although they are not.

e.g. for itdba = 100001fff
!(gpa & ~0x1fffU) -> 1
!(gpa & ~0x1fffUL) -> 0

So we would report a SIE validity intercept although everything is fine.

Fixes: 166ecb3 ("KVM: s390: vsie: support transactional execution")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:50 +02:00
Konrad Rzeszutek Wilk
9c5eee6056 KVM/VMX: Expose SSBD properly to guests
commit 0aa48468d00959c8a37cd3ac727284f4f7359151 upstream.

The X86_FEATURE_SSBD is an synthetic CPU feature - that is
it bit location has no relevance to the real CPUID 0x7.EBX[31]
bit position. For that we need the new CPU feature name.

Fixes: 52817587e706 ("x86/cpufeatures: Disentangle SSBD enumeration")
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: stable@vger.kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lkml.kernel.org/r/20180521215449.26423-2-konrad.wilk@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:50 +02:00
Gustavo A. R. Silva
058dfcf9c2 kernel/sys.c: fix potential Spectre v1 issue
commit 23d6aef74da86a33fa6bb75f79565e0a16ee97c2 upstream.

`resource' can be controlled by user-space, hence leading to a potential
exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

  kernel/sys.c:1474 __do_compat_sys_old_getrlimit() warn: potential spectre issue 'get_current()->signal->rlim' (local cap)
  kernel/sys.c:1455 __do_sys_old_getrlimit() warn: potential spectre issue 'get_current()->signal->rlim' (local cap)

Fix this by sanitizing *resource* before using it to index
current->signal->rlim

Notice that given that speculation windows are large, the policy is to
kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2

Link: http://lkml.kernel.org/r/20180515030038.GA11822@embeddedor.com
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.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>
2018-05-30 07:51:50 +02:00
David Hildenbrand
1da530fe15 kasan: fix memory hotplug during boot
commit 3f1959721558a976aaf9c2024d5bc884e6411bf7 upstream.

Using module_init() is wrong.  E.g.  ACPI adds and onlines memory before
our memory notifier gets registered.

This makes sure that ACPI memory detected during boot up will not result
in a kernel crash.

Easily reproducible with QEMU, just specify a DIMM when starting up.

Link: http://lkml.kernel.org/r/20180522100756.18478-3-david@redhat.com
Fixes: 786a8959912e ("kasan: disable memory hotplug")
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.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>
2018-05-30 07:51:50 +02:00
David Hildenbrand
b052960484 kasan: free allocated shadow memory on MEM_CANCEL_ONLINE
commit ed1596f9ab958dd156a66c9ff1029d3761c1786a upstream.

We have to free memory again when we cancel onlining, otherwise a later
onlining attempt will fail.

Link: http://lkml.kernel.org/r/20180522100756.18478-2-david@redhat.com
Fixes: fa69b5989bb0 ("mm/kasan: add support for memory hotplug")
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.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>
2018-05-30 07:51:49 +02:00
Andrey Ryabinin
9c7821c67a mm/kasan: don't vfree() nonexistent vm_area
commit 0f901dcbc31f88ae41a2aaa365f7802b5d520a28 upstream.

KASAN uses different routines to map shadow for hot added memory and
memory obtained in boot process.  Attempt to offline memory onlined by
normal boot process leads to this:

    Trying to vfree() nonexistent vm area (000000005d3b34b9)
    WARNING: CPU: 2 PID: 13215 at mm/vmalloc.c:1525 __vunmap+0x147/0x190

    Call Trace:
     kasan_mem_notifier+0xad/0xb9
     notifier_call_chain+0x166/0x260
     __blocking_notifier_call_chain+0xdb/0x140
     __offline_pages+0x96a/0xb10
     memory_subsys_offline+0x76/0xc0
     device_offline+0xb8/0x120
     store_mem_state+0xfa/0x120
     kernfs_fop_write+0x1d5/0x320
     __vfs_write+0xd4/0x530
     vfs_write+0x105/0x340
     SyS_write+0xb0/0x140

Obviously we can't call vfree() to free memory that wasn't allocated via
vmalloc().  Use find_vm_area() to see if we can call vfree().

Unfortunately it's a bit tricky to properly unmap and free shadow
allocated during boot, so we'll have to keep it.  If memory will come
online again that shadow will be reused.

Matthew asked: how can you call vfree() on something that isn't a
vmalloc address?

  vfree() is able to free any address returned by
  __vmalloc_node_range().  And __vmalloc_node_range() gives you any
  address you ask.  It doesn't have to be an address in [VMALLOC_START,
  VMALLOC_END] range.

  That's also how the module_alloc()/module_memfree() works on
  architectures that have designated area for modules.

[aryabinin@virtuozzo.com: improve comments]
  Link: http://lkml.kernel.org/r/dabee6ab-3a7a-51cd-3b86-5468718e0390@virtuozzo.com
[akpm@linux-foundation.org: fix typos, reflow comment]
Link: http://lkml.kernel.org/r/20180201163349.8700-1-aryabinin@virtuozzo.com
Fixes: fa69b5989bb0 ("mm/kasan: add support for memory hotplug")
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: Paul Menzel <pmenzel+linux-kasan-dev@molgen.mpg.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.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>
2018-05-30 07:51:49 +02:00
Davidlohr Bueso
afdc490b36 ipc/shm: fix shmat() nil address after round-down when remapping
commit 8f89c007b6dec16a1793cb88de88fcc02117bbbc upstream.

shmat()'s SHM_REMAP option forbids passing a nil address for; this is in
fact the very first thing we check for.  Andrea reported that for
SHM_RND|SHM_REMAP cases we can end up bypassing the initial addr check,
but we need to check again if the address was rounded down to nil.  As
of this patch, such cases will return -EINVAL.

Link: http://lkml.kernel.org/r/20180503204934.kk63josdu6u53fbd@linux-n805
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@vger.kernel.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>
2018-05-30 07:51:49 +02:00
Davidlohr Bueso
67dd0bad81 Revert "ipc/shm: Fix shmat mmap nil-page protection"
commit a73ab244f0dad8fffb3291b905f73e2d3eaa7c00 upstream.

Patch series "ipc/shm: shmat() fixes around nil-page".

These patches fix two issues reported[1] a while back by Joe and Andrea
around how shmat(2) behaves with nil-page.

The first reverts a commit that it was incorrectly thought that mapping
nil-page (address=0) was a no no with MAP_FIXED.  This is not the case,
with the exception of SHM_REMAP; which is address in the second patch.

I chose two patches because it is easier to backport and it explicitly
reverts bogus behaviour.  Both patches ought to be in -stable and ltp
testcases need updated (the added testcase around the cve can be
modified to just test for SHM_RND|SHM_REMAP).

[1] lkml.kernel.org/r/20180430172152.nfa564pvgpk3ut7p@linux-n805

This patch (of 2):

Commit 95e91b831f87 ("ipc/shm: Fix shmat mmap nil-page protection")
worked on the idea that we should not be mapping as root addr=0 and
MAP_FIXED.  However, it was reported that this scenario is in fact
valid, thus making the patch both bogus and breaks userspace as well.

For example X11's libint10.so relies on shmat(1, SHM_RND) for lowmem
initialization[1].

[1] https://cgit.freedesktop.org/xorg/xserver/tree/hw/xfree86/os-support/linux/int10/linux.c#n347
Link: http://lkml.kernel.org/r/20180503203243.15045-2-dave@stgolabs.net
Fixes: 95e91b831f87 ("ipc/shm: Fix shmat mmap nil-page protection")
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reported-by: Joe Lawrence <joe.lawrence@redhat.com>
Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@vger.kernel.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>
2018-05-30 07:51:49 +02:00
Matthew Wilcox
0472f94cef idr: fix invalid ptr dereference on item delete
commit 7a4deea1aa8bddfed4ef1b35fc2b6732563d8ad5 upstream.

If the radix tree underlying the IDR happens to be full and we attempt
to remove an id which is larger than any id in the IDR, we will call
__radix_tree_delete() with an uninitialised 'slot' pointer, at which
point anything could happen.  This was easiest to hit with a single
entry at id 0 and attempting to remove a non-0 id, but it could have
happened with 64 entries and attempting to remove an id >= 64.

Roman said:

  The syzcaller test boils down to opening /dev/kvm, creating an
  eventfd, and calling a couple of KVM ioctls. None of this requires
  superuser. And the result is dereferencing an uninitialized pointer
  which is likely a crash. The specific path caught by syzbot is via
  KVM_HYPERV_EVENTD ioctl which is new in 4.17. But I guess there are
  other user-triggerable paths, so cc:stable is probably justified.

Matthew added:

  We have around 250 calls to idr_remove() in the kernel today. Many of
  them pass an ID which is embedded in the object they're removing, so
  they're safe. Picking a few likely candidates:

  drivers/firewire/core-cdev.c looks unsafe; the ID comes from an ioctl.
  drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c is similar
  drivers/atm/nicstar.c could be taken down by a handcrafted packet

Link: http://lkml.kernel.org/r/20180518175025.GD6361@bombadil.infradead.org
Fixes: 0a835c4f090a ("Reimplement IDR and IDA using the radix tree")
Reported-by: <syzbot+35666cba7f0a337e2e79@syzkaller.appspotmail.com>
Debugged-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: <stable@vger.kernel.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>
2018-05-30 07:51:49 +02:00