[PATCH] kvm: allocate correct size for dirty bitmap

["Bruce Rogers" <brogers@xxxxxxxxxx>]

The dirty bitmap copied out to userspace is stored in a long array, and gets copied out to userspace accordingly.  This patch accounts for that correctly.  Currently I'm seeing kvm crashing due to writing beyond the end of the alloc'd dirty bitmap memory, because the buffer has the wrong size.

Signed-off-by: Bruce Rogers 
---
 qemu-kvm.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/qemu-kvm.c b/qemu-kvm.c
index 6511cb6..ee5db76 100644
--- a/qemu-kvm.c
+++ b/qemu-kvm.c
@@ -702,7 +702,7 @@ int kvm_get_dirty_pages_range(kvm_context_t kvm, unsigned long phys_addr,
     for (i = 0; i < KVM_MAX_NUM_MEM_REGIONS; ++i) {
         if ((slots[i].len && (uint64_t) slots[i].phys_addr >= phys_addr)
             && ((uint64_t) slots[i].phys_addr + slots[i].len <= end_addr)) {
-            buf = qemu_malloc((slots[i].len / 4096 + 7) / 8 + 2);
+            buf = qemu_malloc(BITMAP_SIZE(slots[i].len));
             r = kvm_get_map(kvm, KVM_GET_DIRTY_LOG, i, buf);
             if (r) {
                 qemu_free(buf);


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