Commit bb4945e6 authored by Radim Krčmář's avatar Radim Krčmář
Browse files

Merge tag 'kvm-s390-master-4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux

KVM: s390: fixes for cmma migration

Two fixes for potential bitmap overruns in the cmma migration
code.
parents 0cb5b306 c2cf265d
......@@ -792,11 +792,12 @@ static int kvm_s390_vm_start_migration(struct kvm *kvm)
if (kvm->arch.use_cmma) {
/*
* Get the last slot. They should be sorted by base_gfn, so the
* last slot is also the one at the end of the address space.
* We have verified above that at least one slot is present.
* Get the first slot. They are reverse sorted by base_gfn, so
* the first slot is also the one at the end of the address
* space. We have verified above that at least one slot is
* present.
*/
ms = slots->memslots + slots->used_slots - 1;
ms = slots->memslots;
/* round up so we only use full longs */
ram_pages = roundup(ms->base_gfn + ms->npages, BITS_PER_LONG);
/* allocate enough bytes to store all the bits */
......
......@@ -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);
......
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