diff options
| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2017-12-21 09:18:22 +0100 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2017-12-22 15:22:41 +0100 |
| commit | c2cf265d860882b51a200e4a7553c17827f2b730 (patch) | |
| tree | 2383bf77fda6cc74aba2c3d11f3fd9084c003011 | |
| parent | 32aa144fc32abfcbf7140f473dfbd94c5b9b4105 (diff) | |
KVM: s390: prevent buffer overrun on memory hotplug during migration
We must not go beyond the pre-allocated buffer. This can happen when
a new memory slot is added during migration.
Reported-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # 4.13+
Fixes: 190df4a212a7 (KVM: s390: CMMA tracking, ESSA emulation, migration mode)
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
| -rw-r--r-- | arch/s390/kvm/priv.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index 572496c688cc..0714bfa56da0 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -1006,7 +1006,7 @@ static inline int do_essa(struct kvm_vcpu *vcpu, const int orc) cbrlo[entries] = gfn << PAGE_SHIFT; } - if (orc) { + if (orc && gfn < ms->bitmap_size) { /* increment only if we are really flipping the bit to 1 */ if (!test_and_set_bit(gfn, ms->pgste_bitmap)) atomic64_inc(&ms->dirty_pages); |