<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch, branch v4.19-rc3</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-09-09T14:05:15+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-09-09T14:05:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9a5682765a2e5f93cf2fe7b612b8072b18f0c68a'/>
<id>9a5682765a2e5f93cf2fe7b612b8072b18f0c68a</id>
<content type='text'>
Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for x86:

   - Prevent multiplication result truncation on 32bit. Introduced with
     the early timestamp reworrk.

   - Ensure microcode revision storage to be consistent under all
     circumstances

   - Prevent write tearing of PTEs

   - Prevent confusion of user and kernel reegisters when dumping fatal
     signals verbosely

   - Make an error return value in a failure path of the vector
     allocation negative. Returning EINVAL might the caller assume
     success and causes further wreckage.

   - A trivial kernel doc warning fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Use WRITE_ONCE() when setting PTEs
  x86/apic/vector: Make error return value negative
  x86/process: Don't mix user/kernel regs in 64bit __show_regs()
  x86/tsc: Prevent result truncation on 32bit
  x86: Fix kernel-doc atomic.h warnings
  x86/microcode: Update the new microcode revision unconditionally
  x86/microcode: Make sure boot_cpu_data.microcode is up-to-date
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for x86:

   - Prevent multiplication result truncation on 32bit. Introduced with
     the early timestamp reworrk.

   - Ensure microcode revision storage to be consistent under all
     circumstances

   - Prevent write tearing of PTEs

   - Prevent confusion of user and kernel reegisters when dumping fatal
     signals verbosely

   - Make an error return value in a failure path of the vector
     allocation negative. Returning EINVAL might the caller assume
     success and causes further wreckage.

   - A trivial kernel doc warning fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Use WRITE_ONCE() when setting PTEs
  x86/apic/vector: Make error return value negative
  x86/process: Don't mix user/kernel regs in 64bit __show_regs()
  x86/tsc: Prevent result truncation on 32bit
  x86: Fix kernel-doc atomic.h warnings
  x86/microcode: Update the new microcode revision unconditionally
  x86/microcode: Make sure boot_cpu_data.microcode is up-to-date
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm</title>
<updated>2018-09-08T22:52:45+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-09-08T22:52:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f8f65382c98a28e3c2b20df9dd4231dca5a11682'/>
<id>f8f65382c98a28e3c2b20df9dd4231dca5a11682</id>
<content type='text'>
Pull KVM fixes from Radim Krčmář:
 "ARM:
   - Fix a VFP corruption in 32-bit guest
   - Add missing cache invalidation for CoW pages
   - Two small cleanups

  s390:
   - Fallout from the hugetlbfs support: pfmf interpretion and locking
   - VSIE: fix keywrapping for nested guests

  PPC:
   - Fix a bug where pages might not get marked dirty, causing guest
     memory corruption on migration
   - Fix a bug causing reads from guest memory to use the wrong guest
     real address for very large HPT guests (&gt;256G of memory), leading
     to failures in instruction emulation.

  x86:
   - Fix out of bound access from malicious pv ipi hypercalls
     (introduced in rc1)
   - Fix delivery of pending interrupts when entering a nested guest,
     preventing arbitrarily late injection
   - Sanitize kvm_stat output after destroying a guest
   - Fix infinite loop when emulating a nested guest page fault and
     improve the surrounding emulation code
   - Two minor cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (28 commits)
  KVM: LAPIC: Fix pv ipis out-of-bounds access
  KVM: nVMX: Fix loss of pending IRQ/NMI before entering L2
  arm64: KVM: Remove pgd_lock
  KVM: Remove obsolete kvm_unmap_hva notifier backend
  arm64: KVM: Only force FPEXC32_EL2.EN if trapping FPSIMD
  KVM: arm/arm64: Clean dcache to PoC when changing PTE due to CoW
  KVM: s390: Properly lock mm context allow_gmap_hpage_1m setting
  KVM: s390: vsie: copy wrapping keys to right place
  KVM: s390: Fix pfmf and conditional skey emulation
  tools/kvm_stat: re-animate display of dead guests
  tools/kvm_stat: indicate dead guests as such
  tools/kvm_stat: handle guest removals more gracefully
  tools/kvm_stat: don't reset stats when setting PID filter for debugfs
  tools/kvm_stat: fix updates for dead guests
  tools/kvm_stat: fix handling of invalid paths in debugfs provider
  tools/kvm_stat: fix python3 issues
  KVM: x86: Unexport x86_emulate_instruction()
  KVM: x86: Rename emulate_instruction() to kvm_emulate_instruction()
  KVM: x86: Do not re-{try,execute} after failed emulation in L2
  KVM: x86: Default to not allowing emulation retry in kvm_mmu_page_fault
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull KVM fixes from Radim Krčmář:
 "ARM:
   - Fix a VFP corruption in 32-bit guest
   - Add missing cache invalidation for CoW pages
   - Two small cleanups

  s390:
   - Fallout from the hugetlbfs support: pfmf interpretion and locking
   - VSIE: fix keywrapping for nested guests

  PPC:
   - Fix a bug where pages might not get marked dirty, causing guest
     memory corruption on migration
   - Fix a bug causing reads from guest memory to use the wrong guest
     real address for very large HPT guests (&gt;256G of memory), leading
     to failures in instruction emulation.

  x86:
   - Fix out of bound access from malicious pv ipi hypercalls
     (introduced in rc1)
   - Fix delivery of pending interrupts when entering a nested guest,
     preventing arbitrarily late injection
   - Sanitize kvm_stat output after destroying a guest
   - Fix infinite loop when emulating a nested guest page fault and
     improve the surrounding emulation code
   - Two minor cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (28 commits)
  KVM: LAPIC: Fix pv ipis out-of-bounds access
  KVM: nVMX: Fix loss of pending IRQ/NMI before entering L2
  arm64: KVM: Remove pgd_lock
  KVM: Remove obsolete kvm_unmap_hva notifier backend
  arm64: KVM: Only force FPEXC32_EL2.EN if trapping FPSIMD
  KVM: arm/arm64: Clean dcache to PoC when changing PTE due to CoW
  KVM: s390: Properly lock mm context allow_gmap_hpage_1m setting
  KVM: s390: vsie: copy wrapping keys to right place
  KVM: s390: Fix pfmf and conditional skey emulation
  tools/kvm_stat: re-animate display of dead guests
  tools/kvm_stat: indicate dead guests as such
  tools/kvm_stat: handle guest removals more gracefully
  tools/kvm_stat: don't reset stats when setting PID filter for debugfs
  tools/kvm_stat: fix updates for dead guests
  tools/kvm_stat: fix handling of invalid paths in debugfs provider
  tools/kvm_stat: fix python3 issues
  KVM: x86: Unexport x86_emulate_instruction()
  KVM: x86: Rename emulate_instruction() to kvm_emulate_instruction()
  KVM: x86: Do not re-{try,execute} after failed emulation in L2
  KVM: x86: Default to not allowing emulation retry in kvm_mmu_page_fault
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc</title>
<updated>2018-09-08T22:38:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-09-08T22:38:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0f3aa48ad4c307fb72b8eb43add26c8f314d396a'/>
<id>0f3aa48ad4c307fb72b8eb43add26c8f314d396a</id>
<content type='text'>
Pull ARM SoC fixes from Olof Johansson:
 "A few more fixes who have trickled in:

   - MMC bus width fixup for some Allwinner platforms

   - Fix for NULL deref in ti-aemif when no platform data is passed in

   - Fix div by 0 in SCMI code

   - Add a missing module alias in a new RPi driver"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  memory: ti-aemif: fix a potential NULL-pointer dereference
  firmware: arm_scmi: fix divide by zero when sustained_perf_level is zero
  hwmon: rpi: add module alias to raspberrypi-hwmon
  arm64: allwinner: dts: h6: fix Pine H64 MMC bus width
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ARM SoC fixes from Olof Johansson:
 "A few more fixes who have trickled in:

   - MMC bus width fixup for some Allwinner platforms

   - Fix for NULL deref in ti-aemif when no platform data is passed in

   - Fix div by 0 in SCMI code

   - Add a missing module alias in a new RPi driver"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  memory: ti-aemif: fix a potential NULL-pointer dereference
  firmware: arm_scmi: fix divide by zero when sustained_perf_level is zero
  hwmon: rpi: add module alias to raspberrypi-hwmon
  arm64: allwinner: dts: h6: fix Pine H64 MMC bus width
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'sunxi-fixes-for-4.19' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into fixes</title>
<updated>2018-09-08T17:04:37+00:00</updated>
<author>
<name>Olof Johansson</name>
<email>olof@lixom.net</email>
</author>
<published>2018-09-08T17:04:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a132bb90414bfad4f8ee23cb45fe6946a89b167d'/>
<id>a132bb90414bfad4f8ee23cb45fe6946a89b167d</id>
<content type='text'>
Allwinner fixes for 4.19

Just one fix for H6 mmc on the Pine H64: the mmc bus width was missing
from the device tree. This was added in 4.19-rc1.

* tag 'sunxi-fixes-for-4.19' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
  arm64: allwinner: dts: h6: fix Pine H64 MMC bus width

Signed-off-by: Olof Johansson &lt;olof@lixom.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Allwinner fixes for 4.19

Just one fix for H6 mmc on the Pine H64: the mmc bus width was missing
from the device tree. This was added in 4.19-rc1.

* tag 'sunxi-fixes-for-4.19' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
  arm64: allwinner: dts: h6: fix Pine H64 MMC bus width

Signed-off-by: Olof Johansson &lt;olof@lixom.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/mm: Use WRITE_ONCE() when setting PTEs</title>
<updated>2018-09-08T10:30:36+00:00</updated>
<author>
<name>Nadav Amit</name>
<email>namit@vmware.com</email>
</author>
<published>2018-09-02T18:14:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9bc4f28af75a91aea0ae383f50b0a430c4509303'/>
<id>9bc4f28af75a91aea0ae383f50b0a430c4509303</id>
<content type='text'>
When page-table entries are set, the compiler might optimize their
assignment by using multiple instructions to set the PTE. This might
turn into a security hazard if the user somehow manages to use the
interim PTE. L1TF does not make our lives easier, making even an interim
non-present PTE a security hazard.

Using WRITE_ONCE() to set PTEs and friends should prevent this potential
security hazard.

I skimmed the differences in the binary with and without this patch. The
differences are (obviously) greater when CONFIG_PARAVIRT=n as more
code optimizations are possible. For better and worse, the impact on the
binary with this patch is pretty small. Skimming the code did not cause
anything to jump out as a security hazard, but it seems that at least
move_soft_dirty_pte() caused set_pte_at() to use multiple writes.

Signed-off-by: Nadav Amit &lt;namit@vmware.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Sean Christopherson &lt;sean.j.christopherson@intel.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180902181451.80520-1-namit@vmware.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When page-table entries are set, the compiler might optimize their
assignment by using multiple instructions to set the PTE. This might
turn into a security hazard if the user somehow manages to use the
interim PTE. L1TF does not make our lives easier, making even an interim
non-present PTE a security hazard.

Using WRITE_ONCE() to set PTEs and friends should prevent this potential
security hazard.

I skimmed the differences in the binary with and without this patch. The
differences are (obviously) greater when CONFIG_PARAVIRT=n as more
code optimizations are possible. For better and worse, the impact on the
binary with this patch is pretty small. Skimming the code did not cause
anything to jump out as a security hazard, but it seems that at least
move_soft_dirty_pte() caused set_pte_at() to use multiple writes.

Signed-off-by: Nadav Amit &lt;namit@vmware.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Sean Christopherson &lt;sean.j.christopherson@intel.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180902181451.80520-1-namit@vmware.com

</pre>
</div>
</content>
</entry>
<entry>
<title>x86/apic/vector: Make error return value negative</title>
<updated>2018-09-08T10:12:40+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2018-09-08T10:07:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=47b7360ce563e18c524ce92b55fb4da72b3b3578'/>
<id>47b7360ce563e18c524ce92b55fb4da72b3b3578</id>
<content type='text'>
activate_managed() returns EINVAL instead of -EINVAL in case of
error. While this is unlikely to happen, the positive return value would
cause further malfunction at the call site.

Fixes: 2db1f959d9dc ("x86/vector: Handle managed interrupts proper")
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: stable@vger.kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
activate_managed() returns EINVAL instead of -EINVAL in case of
error. While this is unlikely to happen, the positive return value would
cause further malfunction at the call site.

Fixes: 2db1f959d9dc ("x86/vector: Handle managed interrupts proper")
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: stable@vger.kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'arc-4.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc</title>
<updated>2018-09-07T23:45:32+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-09-07T23:45:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2c34a0e041a7063e6e3b3be8866a88975f3342d4'/>
<id>2c34a0e041a7063e6e3b3be8866a88975f3342d4</id>
<content type='text'>
Pull ARC updates from Vineet Gupta:

 - Fix for atomic_fetch_#op  [Will Deacon]

 - Enable per device IOC [Eugeniy Paltsev]

 - Remove redundant gcc version checks [Masahiro Yamada]

 - Miscll platform config/DT updates [Alexey Brodkin]

* tag 'arc-4.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: don't check for HIGHMEM pages in arch_dma_alloc
  ARC: IOC: panic if both IOC and ZONE_HIGHMEM enabled
  ARC: dma [IOC] Enable per device io coherency
  ARC: dma [IOC]: mark DMA devices connected as dma-coherent
  ARC: atomics: unbork atomic_fetch_##op()
  arc: remove redundant GCC version checks
  ARC: sort Kconfig
  ARC: cleanup show_faulting_vma()
  ARC: [plat-axs*]: Enable SWAP
  ARC: [plat-axs*/plat-hsdk]: Allow U-Boot to pass MAC-address to the kernel
  ARC: configs: cleanup
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ARC updates from Vineet Gupta:

 - Fix for atomic_fetch_#op  [Will Deacon]

 - Enable per device IOC [Eugeniy Paltsev]

 - Remove redundant gcc version checks [Masahiro Yamada]

 - Miscll platform config/DT updates [Alexey Brodkin]

* tag 'arc-4.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: don't check for HIGHMEM pages in arch_dma_alloc
  ARC: IOC: panic if both IOC and ZONE_HIGHMEM enabled
  ARC: dma [IOC] Enable per device io coherency
  ARC: dma [IOC]: mark DMA devices connected as dma-coherent
  ARC: atomics: unbork atomic_fetch_##op()
  arc: remove redundant GCC version checks
  ARC: sort Kconfig
  ARC: cleanup show_faulting_vma()
  ARC: [plat-axs*]: Enable SWAP
  ARC: [plat-axs*/plat-hsdk]: Allow U-Boot to pass MAC-address to the kernel
  ARC: configs: cleanup
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux</title>
<updated>2018-09-07T17:37:23+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-09-07T17:37:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4ff8a142bdb395482dd8744ed5ec2994dc3b81a3'/>
<id>4ff8a142bdb395482dd8744ed5ec2994dc3b81a3</id>
<content type='text'>
Pull arm64 fix from Will Deacon:
 "Just one small fix here, preventing a VM_WARN_ON when a !present
  PMD/PUD is "freed" as part of a huge ioremap() operation.

  The correct behaviour is to skip the free silently in this case, which
  is a little weird (the function is a bit of a misnomer), but it
  follows the x86 implementation"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: fix erroneous warnings in page freeing functions
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull arm64 fix from Will Deacon:
 "Just one small fix here, preventing a VM_WARN_ON when a !present
  PMD/PUD is "freed" as part of a huge ioremap() operation.

  The correct behaviour is to skip the free silently in this case, which
  is a little weird (the function is a bit of a misnomer), but it
  follows the x86 implementation"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: fix erroneous warnings in page freeing functions
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: LAPIC: Fix pv ipis out-of-bounds access</title>
<updated>2018-09-07T16:38:43+00:00</updated>
<author>
<name>Wanpeng Li</name>
<email>wanpengli@tencent.com</email>
</author>
<published>2018-08-30T02:03:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bdf7ffc89922a52a4f08a12f7421ea24bb7626a0'/>
<id>bdf7ffc89922a52a4f08a12f7421ea24bb7626a0</id>
<content type='text'>
Dan Carpenter reported that the untrusted data returns from kvm_register_read()
results in the following static checker warning:
  arch/x86/kvm/lapic.c:576 kvm_pv_send_ipi()
  error: buffer underflow 'map-&gt;phys_map' 's32min-s32max'

KVM guest can easily trigger this by executing the following assembly sequence
in Ring0:

mov $10, %rax
mov $0xFFFFFFFF, %rbx
mov $0xFFFFFFFF, %rdx
mov $0, %rsi
vmcall

As this will cause KVM to execute the following code-path:
vmx_handle_exit() -&gt; handle_vmcall() -&gt; kvm_emulate_hypercall() -&gt; kvm_pv_send_ipi()
which will reach out-of-bounds access.

This patch fixes it by adding a check to kvm_pv_send_ipi() against map-&gt;max_apic_id,
ignoring destinations that are not present and delivering the rest. We also check
whether or not map-&gt;phys_map[min + i] is NULL since the max_apic_id is set to the
max apic id, some phys_map maybe NULL when apic id is sparse, especially kvm
unconditionally set max_apic_id to 255 to reserve enough space for any xAPIC ID.

Reported-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Reviewed-by: Liran Alon &lt;liran.alon@oracle.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Cc: Liran Alon &lt;liran.alon@oracle.com&gt;
Cc: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Wanpeng Li &lt;wanpengli@tencent.com&gt;
[Add second "if (min &gt; map-&gt;max_apic_id)" to complete the fix. -Radim]
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Dan Carpenter reported that the untrusted data returns from kvm_register_read()
results in the following static checker warning:
  arch/x86/kvm/lapic.c:576 kvm_pv_send_ipi()
  error: buffer underflow 'map-&gt;phys_map' 's32min-s32max'

KVM guest can easily trigger this by executing the following assembly sequence
in Ring0:

mov $10, %rax
mov $0xFFFFFFFF, %rbx
mov $0xFFFFFFFF, %rdx
mov $0, %rsi
vmcall

As this will cause KVM to execute the following code-path:
vmx_handle_exit() -&gt; handle_vmcall() -&gt; kvm_emulate_hypercall() -&gt; kvm_pv_send_ipi()
which will reach out-of-bounds access.

This patch fixes it by adding a check to kvm_pv_send_ipi() against map-&gt;max_apic_id,
ignoring destinations that are not present and delivering the rest. We also check
whether or not map-&gt;phys_map[min + i] is NULL since the max_apic_id is set to the
max apic id, some phys_map maybe NULL when apic id is sparse, especially kvm
unconditionally set max_apic_id to 255 to reserve enough space for any xAPIC ID.

Reported-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Reviewed-by: Liran Alon &lt;liran.alon@oracle.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Cc: Liran Alon &lt;liran.alon@oracle.com&gt;
Cc: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: Wanpeng Li &lt;wanpengli@tencent.com&gt;
[Add second "if (min &gt; map-&gt;max_apic_id)" to complete the fix. -Radim]
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: nVMX: Fix loss of pending IRQ/NMI before entering L2</title>
<updated>2018-09-07T16:38:42+00:00</updated>
<author>
<name>Liran Alon</name>
<email>liran.alon@oracle.com</email>
</author>
<published>2018-09-03T12:20:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b5861e5cf2fcf83031ea3e26b0a69d887adf7d21'/>
<id>b5861e5cf2fcf83031ea3e26b0a69d887adf7d21</id>
<content type='text'>
Consider the case L1 had a IRQ/NMI event until it executed
VMLAUNCH/VMRESUME which wasn't delivered because it was disallowed
(e.g. interrupts disabled). When L1 executes VMLAUNCH/VMRESUME,
L0 needs to evaluate if this pending event should cause an exit from
L2 to L1 or delivered directly to L2 (e.g. In case L1 don't intercept
EXTERNAL_INTERRUPT).

Usually this would be handled by L0 requesting a IRQ/NMI window
by setting VMCS accordingly. However, this setting was done on
VMCS01 and now VMCS02 is active instead. Thus, when L1 executes
VMLAUNCH/VMRESUME we force L0 to perform pending event evaluation by
requesting a KVM_REQ_EVENT.

Note that above scenario exists when L1 KVM is about to enter L2 but
requests an "immediate-exit". As in this case, L1 will
disable-interrupts and then send a self-IPI before entering L2.

Reviewed-by: Nikita Leshchenko &lt;nikita.leshchenko@oracle.com&gt;
Co-developed-by: Sean Christopherson &lt;sean.j.christopherson@intel.com&gt;
Signed-off-by: Sean Christopherson &lt;sean.j.christopherson@intel.com&gt;
Signed-off-by: Liran Alon &lt;liran.alon@oracle.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Consider the case L1 had a IRQ/NMI event until it executed
VMLAUNCH/VMRESUME which wasn't delivered because it was disallowed
(e.g. interrupts disabled). When L1 executes VMLAUNCH/VMRESUME,
L0 needs to evaluate if this pending event should cause an exit from
L2 to L1 or delivered directly to L2 (e.g. In case L1 don't intercept
EXTERNAL_INTERRUPT).

Usually this would be handled by L0 requesting a IRQ/NMI window
by setting VMCS accordingly. However, this setting was done on
VMCS01 and now VMCS02 is active instead. Thus, when L1 executes
VMLAUNCH/VMRESUME we force L0 to perform pending event evaluation by
requesting a KVM_REQ_EVENT.

Note that above scenario exists when L1 KVM is about to enter L2 but
requests an "immediate-exit". As in this case, L1 will
disable-interrupts and then send a self-IPI before entering L2.

Reviewed-by: Nikita Leshchenko &lt;nikita.leshchenko@oracle.com&gt;
Co-developed-by: Sean Christopherson &lt;sean.j.christopherson@intel.com&gt;
Signed-off-by: Sean Christopherson &lt;sean.j.christopherson@intel.com&gt;
Signed-off-by: Liran Alon &lt;liran.alon@oracle.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
