[ Upstream commit c4de37ee2b ]
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>
[ Upstream commit 9a9ab3078e ]
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: eed0eabd12 ("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>
commit a048a07d7f 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>
commit 501a78cbc1 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: abf110f3e1 ("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>
commit 6232774f15 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: f636c14790 ("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>
commit e7347a8683 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>
commit 0f9bdfe3c7 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: f636c14790 ("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>
commit d6fbe1c55c 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>
commit 56986016cb 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>
commit 2e4a16161f 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>
commit 37c0bdd00d 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>
commit ff348355e9 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>
commit 8ad3304156 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>
commit 77addf6e95 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>
commit f636c14790 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>
commit 9a868f6343 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>
commit c4bc36628d 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>
commit 0063d61ccf 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>
commit 84749a58b6 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>
commit abf110f3e1 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>
commit 1e2a9fc749 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>
commit eb0a2d2620 upstream.
Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.
Fixes: 6e032b350c ("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>
commit 582605a429 upstream.
Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.
Fixes: 8989d56878 ("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>
commit bdcb1aefc5 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>
commit d8f2f498d9 upstream.
Since 4.10, commit 8003c9ae20 (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: 8003c9ae20
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>
commit 1eaafe91a0 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: 28c1c9fabf ("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>
commit c4d2188206 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>
commit 0f901dcbc3 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: fa69b5989b ("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>
commit a73ab244f0 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 95e91b831f ("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: 95e91b831f ("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>
commit 7a4deea1aa 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: 0a835c4f09 ("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>
commit f7068114d4 upstream.
We're casting the CDROM layer request_sense to the SCSI sense
buffer, but the former is 64 bytes and the latter is 96 bytes.
As we generally allocate these on the stack, we end up blowing
up the stack.
Fix this by wrapping the scsi_execute() call with a properly
sized sense buffer, and copying back the bits for the CDROM
layer.
Cc: stable@vger.kernel.org
Reported-by: Piotr Gabriel Kosinski <pg.kosinski@gmail.com>
Reported-by: Daniel Shapira <daniel@twistlock.com>
Tested-by: Kees Cook <keescook@chromium.org>
Fixes: 82ed4db499 ("block: split scsi_request out of struct request")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8e907ed488 upstream.
User-space may invoke ibv_reg_mr and ibv_dereg_mr in different threads.
If ibv_dereg_mr is called after the thread which invoked ibv_reg_mr has
exited, get_pid_task will return NULL and ib_umem_release will not
decrease mm->pinned_vm.
Instead of using threads to locate the mm, use the overall tgid from the
ib_ucontext struct instead. This matches the behavior of ODP and
disassociate in handling the mm of the process that called ibv_reg_mr.
Cc: <stable@vger.kernel.org>
Fixes: 87773dd56d ("IB: ib_umem_release() should decrement mm->pinned_vm from ib_umem_get")
Signed-off-by: Lidong Chen <lidongchen@tencent.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f9e76ca377 upstream.
A pio send egress error can occur when the PSM library attempts to
to send a bad packet. That issue is still being investigated.
The pio error interrupt handler then attempts to progress the recovery
of the errored pio send context.
Code inspection reveals that the handling lacks the necessary locking
if that recovery interleaves with a PSM close of the "context" object
contains the pio send context.
The lack of the locking can cause the recovery to access the already
freed pio send context object and incorrectly deduce that the pio
send context is actually a kernel pio send context as shown by the
NULL deref stack below:
[<ffffffff8143d78c>] _dev_info+0x6c/0x90
[<ffffffffc0613230>] sc_restart+0x70/0x1f0 [hfi1]
[<ffffffff816ab124>] ? __schedule+0x424/0x9b0
[<ffffffffc06133c5>] sc_halted+0x15/0x20 [hfi1]
[<ffffffff810aa3ba>] process_one_work+0x17a/0x440
[<ffffffff810ab086>] worker_thread+0x126/0x3c0
[<ffffffff810aaf60>] ? manage_workers.isra.24+0x2a0/0x2a0
[<ffffffff810b252f>] kthread+0xcf/0xe0
[<ffffffff810b2460>] ? insert_kthread_work+0x40/0x40
[<ffffffff816b8798>] ret_from_fork+0x58/0x90
[<ffffffff810b2460>] ? insert_kthread_work+0x40/0x40
This is the best case scenario and other scenarios can corrupt the
already freed memory.
Fix by adding the necessary locking in the pio send context error
handler.
Cc: <stable@vger.kernel.org> # 4.9.x
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit faf37c44a1 upstream.
Clear the PCR (Processor Compatibility Register) on boot to ensure we
are not running in a compatibility mode.
We've seen this cause problems when a crash (and kdump) occurs while
running compat mode guests. The kdump kernel then runs with the PCR
set and causes problems. The symptom in the kdump kernel (also seen in
petitboot after fast-reboot) is early userspace programs taking
sigills on newer instructions (seen in libc).
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 32c3fa7cdf upstream.
For LSE atomics that read and write a register operand, we need to
ensure that these operands are annotated as "early clobber" if the
register is written before all of the input operands have been consumed.
Failure to do so can result in the compiler allocating the same register
to both operands, leading to splats such as:
Unable to handle kernel paging request at virtual address 11111122222221
[...]
x1 : 1111111122222222 x0 : 1111111122222221
Process swapper/0 (pid: 1, stack limit = 0x000000008209f908)
Call trace:
test_atomic64+0x1360/0x155c
where x0 has been allocated as both the value to be stored and also the
atomic_t pointer.
This patch adds the missing clobbers.
Cc: <stable@vger.kernel.org>
Cc: Dave Martin <dave.martin@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Reported-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 938ae7259c upstream.
Depending on whether the kernel is compiled with frame-pointer or not,
the temporary memory location used for the bp parameter in these macros
is referenced relative to the stack pointer or the frame pointer.
Hence we can never reference that parameter when we've modified either
the stack pointer or the frame pointer, because then the compiler would
generate an incorrect stack reference.
Fix this by pushing the temporary memory parameter on a known location on
the stack before modifying the stack- and frame pointers.
Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4855c92dbb upstream.
When run raidconfig from Dom0 we found that the Xen DMA heap is reduced,
but Dom Heap is increased by the same size. Tracing raidconfig we found
that the related ioctl() in megaraid_sas will call dma_alloc_coherent()
to apply memory. If the memory allocated by Dom0 is not in the DMA area,
it will exchange memory with Xen to meet the requiment. Later drivers
call dma_free_coherent() to free the memory, on xen_swiotlb_free_coherent()
the check condition (dev_addr + size - 1 <= dma_mask) is always false,
it prevents calling xen_destroy_contiguous_region() to return the memory
to the Xen DMA heap.
This issue introduced by commit 6810df88dc "xen-swiotlb: When doing
coherent alloc/dealloc check before swizzling the MFNs.".
Signed-off-by: Joe Jin <joe.jin@oracle.com>
Tested-by: John Sobecki <john.sobecki@oracle.com>
Reviewed-by: Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 136d769e0b upstream.
While whitelisting Micron M500DC drives, the tweaked blacklist entry
enabled queued TRIM from M500IT variants also. But these do not support
queued TRIM. And while using those SSDs with the latest kernel we have
seen errors and even the partition table getting corrupted.
Some part from the dmesg:
[ 6.727384] ata1.00: ATA-9: Micron_M500IT_MTFDDAK060MBD, MU01, max UDMA/133
[ 6.727390] ata1.00: 117231408 sectors, multi 16: LBA48 NCQ (depth 31/32), AA
[ 6.741026] ata1.00: supports DRM functions and may not be fully accessible
[ 6.759887] ata1.00: configured for UDMA/133
[ 6.762256] scsi 0:0:0:0: Direct-Access ATA Micron_M500IT_MT MU01 PQ: 0 ANSI: 5
and then for the error:
[ 120.860334] ata1.00: exception Emask 0x1 SAct 0x7ffc0007 SErr 0x0 action 0x6 frozen
[ 120.860338] ata1.00: irq_stat 0x40000008
[ 120.860342] ata1.00: failed command: SEND FPDMA QUEUED
[ 120.860351] ata1.00: cmd 64/01:00:00:00:00/00:00:00:00:00/a0 tag 0 ncq dma 512 out
res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x5 (timeout)
[ 120.860353] ata1.00: status: { DRDY }
[ 120.860543] ata1: hard resetting link
[ 121.166128] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[ 121.166376] ata1.00: supports DRM functions and may not be fully accessible
[ 121.186238] ata1.00: supports DRM functions and may not be fully accessible
[ 121.204445] ata1.00: configured for UDMA/133
[ 121.204454] ata1.00: device reported invalid CHS sector 0
[ 121.204541] sd 0:0:0:0: [sda] tag#18 UNKNOWN(0x2003) Result: hostbyte=0x00 driverbyte=0x08
[ 121.204546] sd 0:0:0:0: [sda] tag#18 Sense Key : 0x5 [current]
[ 121.204550] sd 0:0:0:0: [sda] tag#18 ASC=0x21 ASCQ=0x4
[ 121.204555] sd 0:0:0:0: [sda] tag#18 CDB: opcode=0x93 93 08 00 00 00 00 00 04 28 80 00 00 00 30 00 00
[ 121.204559] print_req_error: I/O error, dev sda, sector 272512
After few reboots with these errors, and the SSD is corrupted.
After blacklisting it, the errors are not seen and the SSD does not get
corrupted any more.
Fixes: 243918be63 ("libata: Do not blacklist Micron M500DC")
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>