4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Christian Borntraeger <[email protected]> commit c2cf265d860882b51a200e4a7553c17827f2b730 upstream. 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 <[email protected]> Signed-off-by: Christian Borntraeger <[email protected]> Fixes: 190df4a212a7 (KVM: s390: CMMA tracking, ESSA emulation, migration mode) Reviewed-by: Cornelia Huck <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/s390/kvm/priv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -1009,7 +1009,7 @@ static inline int do_essa(struct kvm_vcp 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);
