linux-stable.git/arch, branch v4.8.7

kvm: x86: Check memopp before dereference (CVE-2016-8630)

2016-11-10T15:38:57+00:00

commit d9092f52d7e61dd1557f2db2400ddb430e85937e upstream.

Commit 41061cdb98 ("KVM: emulate: do not initialize memopp") removes a
check for non-NULL under incorrect assumptions. An undefined instruction
with a ModR/M byte with Mod=0 and R/M-5 (e.g. 0xc7 0x15) will attempt
to dereference a null pointer here.

Fixes: 41061cdb98a0bec464278b4db8e894a3121671f5
Message-Id: <1477592752-126650-2-git-send-email-osh@google.com>
Signed-off-by: Owen Hofmann 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

ARM: fix oops when using older ARMv4T CPUs

2016-11-10T15:38:57+00:00

commit 04946fb60fb157faafa01658dff3131d49f49ccb upstream.

Alexander Shiyan reports that CLPS711x fails at boot time in the data
exception handler due to a NULL pointer dereference.  This is caused by
the late-v4t abort handler overwriting R9 (which becomes zero).  Fix
this by making the abort handler save and restore R9.

Unable to handle kernel NULL pointer dereference at virtual address 00000008
pgd = c3b58000
[00000008] *pgd=800000000, *pte=00000000, *ppte=feff4140
Internal error: Oops: 63c11817 [#1] PREEMPT ARM
CPU: 0 PID: 448 Comm: ash Not tainted 4.8.1+ #1
Hardware name: Cirrus Logic CLPS711X (Device Tree Support)
task: c39e03a0 ti: c3b4e000 task.ti: c3b4e000
PC is at __dabt_svc+0x4c/0x60
LR is at do_page_fault+0x144/0x2ac
pc : []    lr : []    psr: 60000093
sp : c3b4fe6c  ip : 00000001  fp : b6f1bf88
r10: c387a5a0  r9 : 00000000  r8 : e4e0e001
r7 : bee3ef83  r6 : 00100000  r5 : 80000013  r4 : c022fcf8
r3 : 00000000  r2 : 00000008  r1 : bf000000  r0 : 00000000
Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 0000217f  Table: c3b58055  DAC: 00000055
Process ash (pid: 448, stack limit = 0xc3b4e190)
Stack: (0xc3b4fe6c to 0xc3b50000)
fe60:                            bee3ef83 c05168d1 ffffffff 00000000 c3adfe80
fe80: c3a03300 00000000 c3b4fed0 c3a03400 bee3ef83 c387a5a0 b6f1bf88 00000001
fea0: c3b4febc 00000076 c022fcf8 80000013 ffffffff 0000003f bf000000 bee3ef83
fec0: 00000004 00000000 c3adfe80 c00e432c 00000812 00000005 00000001 00000006
fee0: b6f1b000 00000000 00010000 0003c944 0004d000 0004d439 00010000 b6f1b000
ff00: 00000005 00000000 00015ecc c3b4fed0 0000000a 00000000 00000000 c00a1dc0
ff20: befff000 c3a03300 c3b4e000 c0507cd8 c0508024 fffffff8 c3a03300 00000000
ff40: c0516a58 c00a35bc c39e03a0 000001c0 bea84ce8 0004e008 c3b3a000 c00a3ac0
ff60: c3b40374 c3b3a000 bea84d11 00000000 c0500188 bea84d11 bea84ce8 00000001
ff80: 0000000b c000a304 c3b4e000 00000000 bea84ce4 c00a3cd0 00000000 bea84d11
ffa0: bea84ce8 c000a160 bea84d11 bea84ce8 bea84d11 bea84ce8 0004e008 0004d450
ffc0: bea84d11 bea84ce8 00000001 0000000b b6f45ee4 00000000 b6f5ff70 bea84ce4
ffe0: b6f2f130 bea84cb0 b6f2f194 b6ef29f4 a0000010 bea84d11 02c7cffa 02c7cffd
[] (__dabt_svc) from [] (__copy_to_user_std+0xf8/0x330)
[] (__copy_to_user_std) from []
+(load_elf_binary+0x920/0x107c)
[] (load_elf_binary) from []
+(search_binary_handler+0x80/0x16c)
[] (search_binary_handler) from []
+(do_execveat_common+0x418/0x600)
[] (do_execveat_common) from [] (do_execve+0x28/0x30)
[] (do_execve) from [] (ret_fast_syscall+0x0/0x30)
Code: e1a0200d eb00136b e321f093 e59d104c (e5891008)
---[ end trace 4b4f8086ebef98c5 ]---

Fixes: e6978e4bf181 ("ARM: save and reset the address limit when entering an exception")
Reported-by: Alexander Shiyan 
Tested-by: Alexander Shiyan 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman

parisc: Ensure consistent state when switching to kernel stack at syscall entry

2016-11-10T15:38:52+00:00

commit 6ed518328d0189e0fdf1bb7c73290d546143ea66 upstream.

We have one critical section in the syscall entry path in which we switch from
the userspace stack to kernel stack. In the event of an external interrupt, the
interrupt code distinguishes between those two states by analyzing the value of
sr7. If sr7 is zero, it uses the kernel stack. Therefore it's important, that
the value of sr7 is in sync with the currently enabled stack.

This patch now disables interrupts while executing the critical section.  This
prevents the interrupt handler to possibly see an inconsistent state which in
the worst case can lead to crashes.

Interestingly, in the syscall exit path interrupts were already disabled in the
critical section which switches back to the userspace stack.

Signed-off-by: John David Anglin 
Signed-off-by: Helge Deller 
Signed-off-by: Greg Kroah-Hartman

MIPS: KASLR: Fix handling of NULL FDT

2016-11-10T15:38:51+00:00

commit 4736697963385e6257ee8e260e97347e858cd962 upstream.

If platform code returns a NULL pointer to the FDT, initial_boot_params
will not get set to a valid pointer and attempting to find the /chosen
node in it will cause a NULL pointer dereference and the kernel to crash
immediately on startup - with no output to the console.

Fix this by checking that initial_boot_params is valid before using it.

Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE")
Signed-off-by: Matt Redfearn 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14414/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

ARM: dts: fix the SD card on the Snowball

2016-11-10T15:38:51+00:00

commit 1b283eea6228880b765bc40fe4e555416437ce58 upstream.

This fixes a very annoying regression on the Snowball SD card
that has been around for a while. It turns out that the device
tree does not configure the direction pins properly, nor sets
up the pins for the voltage converter properly at boot. Unless
all things are correctly set up, the feedback clock will not
work, and makes the driver spew messages in the console (but
it works, very slowly):

root@Ux500:/ mount /dev/mmcblk0p2 /mnt/
[    9.953460] mmci-pl18x 80126000.sdi0_per1: error during DMA transfer!
[    9.960296] mmcblk0: error -110 sending status command, retrying
[    9.966461] mmcblk0: error -110 sending status command, retrying
[    9.972534] mmcblk0: error -110 sending status command, aborting

Fix this by rectifying the device tree to correspond to that of
the Ux500 HREF boards plus the DAT31DIR setting that is unique for
the Snowball, and things start working smoothly. Add in the SDR12
and SDR25 modes which this host can do without any problems.

I don't know if this has ever been correct, sadly. It works after
this patch.

Reported-by: Daniel Lezcano 
Cc: Ulf Hansson 
Signed-off-by: Linus Walleij 
Signed-off-by: Olof Johansson 
Signed-off-by: Greg Kroah-Hartman

ARM: mvebu: Select corediv clk for all mvebu v7 SoC

2016-11-10T15:38:51+00:00

commit 33c45ef8adc8a7cf781b2566d50e6ea8e97b3596 upstream.

Since the commit bd3677ff31a3 ("clk: mvebu: Remove corediv clock from
Armada XP"), the corediv clk is no more selected for Armada XP, however
this clock is used for Armada XP using the compatible
armada-370-corediv-clock.

While since commit 1594d568c6e3 ("clk: mvebu: Move corediv config to
mvebu config") Armada 38x and Armada 375 got corediv support again, not
only Armada XP was missed but also Armada 39x.

Actually all the SoC selecting MVEBU_V7 config need this clock:
git grep "\-corediv-clock" arch/arm/boot/dts
arch/arm/boot/dts/armada-370-xp.dtsi: compatible = "marvell,armada-370-corediv-clock";
arch/arm/boot/dts/armada-375.dtsi:    compatible = "marvell,armada-375-corediv-clock";
arch/arm/boot/dts/armada-38x.dtsi:    compatible = "marvell,armada-380-corediv-clock";
arch/arm/boot/dts/armada-39x.dtsi:    compatible = "marvell,armada-390-corediv-clock"

This commit now fixes this behavior by letting MVEBU_V7 select
MVEBU_CLK_COREDIV.

Fixes: bd3677ff31a3 ("clk: mvebu: Remove corediv clock from Armada XP")
Reported-by: Uwe Kleine-König 
Acked-by: Uwe Kleine-König 
Signed-off-by: Gregory CLEMENT 
Signed-off-by: Greg Kroah-Hartman

KVM: MIPS: Precalculate MMIO load resume PC

2016-11-10T15:38:51+00:00

commit e1e575f6b026734be3b1f075e780e91ab08ca541 upstream.

The advancing of the PC when completing an MMIO load is done before
re-entering the guest, i.e. before restoring the guest ASID. However if
the load is in a branch delay slot it may need to access guest code to
read the prior branch instruction. This isn't safe in TLB mapped code at
the moment, nor in the future when we'll access unmapped guest segments
using direct user accessors too, as it could read the branch from host
user memory instead.

Therefore calculate the resume PC in advance while we're still in the
right context and save it in the new vcpu->arch.io_pc (replacing the no
longer needed vcpu->arch.pending_load_cause), and restore it on MMIO
completion.

Fixes: e685c689f3a8 ("KVM/MIPS32: Privileged instruction/target branch emulation.")
Signed-off-by: James Hogan 
Cc: Paolo Bonzini 
Cc: "Radim Krčmář" 
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

KVM: MIPS: Make ERET handle ERL before EXL

2016-11-10T15:38:51+00:00

commit ede5f3e7b54a4347be4d8525269eae50902bd7cd upstream.

The ERET instruction to return from exception is used for returning from
exception level (Status.EXL) and error level (Status.ERL). If both bits
are set however we should be returning from ERL first, as ERL can
interrupt EXL, for example when an NMI is taken. KVM however checks EXL
first.

Fix the order of the checks to match the pseudocode in the instruction
set manual.

Fixes: e685c689f3a8 ("KVM/MIPS32: Privileged instruction/target branch emulation.")
Signed-off-by: James Hogan 
Cc: Paolo Bonzini 
Cc: "Radim Krčmář" 
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

KVM: s390: Fix STHYI buffer alignment for diag224

2016-11-10T15:38:51+00:00

commit 45c7ee43a5184ddbff652ee0d2e826f86f1b616b upstream.

Diag224 requires a page-aligned 4k buffer to store the name table
into. kmalloc does not guarantee page alignment, hence we replace it
with __get_free_page for the buffer allocation.

Reported-by: Michael Holzheu 
Signed-off-by: Janosch Frank 
Reviewed-by: Cornelia Huck 
Signed-off-by: Christian Borntraeger 
Signed-off-by: Greg Kroah-Hartman

KVM: x86: fix wbinvd_dirty_mask use-after-free

2016-11-10T15:38:51+00:00

commit bd768e146624cbec7122ed15dead8daa137d909d upstream.

vcpu->arch.wbinvd_dirty_mask may still be used after freeing it,
corrupting memory. For example, the following call trace may set a bit
in an already freed cpu mask:
    kvm_arch_vcpu_load
    vcpu_load
    vmx_free_vcpu_nested
    vmx_free_vcpu
    kvm_arch_vcpu_free

Fix this by deferring freeing of wbinvd_dirty_mask.

Signed-off-by: Ido Yariv 
Reviewed-by: Paolo Bonzini 
Signed-off-by: Radim Krčmář 
Signed-off-by: Greg Kroah-Hartman