lkml.org 
[lkml]   [2021]   [Mar]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.19 117/120] KVM: arm64: Fix exclusive limit for IPA size
    Date
    From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    From: Marc Zyngier <maz@kernel.org>

    Commit 262b003d059c6671601a19057e9fe1a5e7f23722 upstream.

    When registering a memslot, we check the size and location of that
    memslot against the IPA size to ensure that we can provide guest
    access to the whole of the memory.

    Unfortunately, this check rejects memslot that end-up at the exact
    limit of the addressing capability for a given IPA size. For example,
    it refuses the creation of a 2GB memslot at 0x8000000 with a 32bit
    IPA space.

    Fix it by relaxing the check to accept a memslot reaching the
    limit of the IPA space.

    Fixes: c3058d5da222 ("arm/arm64: KVM: Ensure memslots are within KVM_PHYS_SIZE")
    Reviewed-by: Eric Auger <eric.auger@redhat.com>
    Signed-off-by: Marc Zyngier <maz@kernel.org>
    Cc: stable@vger.kernel.org # 4.4, 4.9, 4.14, 4.19
    Reviewed-by: Andrew Jones <drjones@redhat.com>
    Link: https://lore.kernel.org/r/20210311100016.3830038-3-maz@kernel.org
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    ---
    virt/kvm/arm/mmu.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/virt/kvm/arm/mmu.c
    +++ b/virt/kvm/arm/mmu.c
    @@ -2080,7 +2080,7 @@ int kvm_arch_prepare_memory_region(struc
    * Prevent userspace from creating a memory region outside of the IPA
    * space addressable by the KVM guest IPA space.
    */
    - if (memslot->base_gfn + memslot->npages >=
    + if (memslot->base_gfn + memslot->npages >
    (KVM_PHYS_SIZE >> PAGE_SHIFT))
    return -EFAULT;


    \
     
     \ /
      Last update: 2021-03-15 15:41    [W:5.919 / U:0.176 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site