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| author | Sean Christopherson <sean.j.christopherson@intel.com> | 2020-04-08 09:40:59 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-04-29 17:31:30 +0300 |
| commit | 4cfcc37091baba19c2bfe46f16201edbca2aa40c (patch) | |
| tree | cc2eea1bf1ed94d6bb0ba0f76626e12bf538da9d /arch | |
| parent | 9c4e0cab837e0b2a3748f376828db426019c6252 (diff) | |
| download | linux-4cfcc37091baba19c2bfe46f16201edbca2aa40c.tar.xz | |
KVM: s390: Return last valid slot if approx index is out-of-bounds
commit 97daa028f3f621adff2c4f7b15fe0874e5b5bd6c upstream.
Return the index of the last valid slot from gfn_to_memslot_approx() if
its binary search loop yielded an out-of-bounds index. The index can
be out-of-bounds if the specified gfn is less than the base of the
lowest memslot (which is also the last valid memslot).
Note, the sole caller, kvm_s390_get_cmma(), ensures used_slots is
non-zero.
Fixes: afdad61615cc3 ("KVM: s390: Fix storage attributes migration with memory slots")
Cc: stable@vger.kernel.org # 4.19.x: 0774a964ef56: KVM: Fix out of range accesses to memslots
Cc: stable@vger.kernel.org # 4.19.x
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200408064059.8957-3-sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 11c3cd906ab4..18662c1a9361 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -1666,6 +1666,9 @@ static int gfn_to_memslot_approx(struct kvm_memslots *slots, gfn_t gfn) start = slot + 1; } + if (start >= slots->used_slots) + return slots->used_slots - 1; + if (gfn >= memslots[start].base_gfn && gfn < memslots[start].base_gfn + memslots[start].npages) { atomic_set(&slots->lru_slot, start); |