[Qemu-stable] [PATCH 26/43] qcow2: Fix refcount table size calculation

[Michael Roth]

From: Kevin Wolf <address@hidden>

A missing factor for the refcount table entry size in the calculation
could mean that too little memory was allocated for the in-memory
representation of the table, resulting in a buffer overflow.

Signed-off-by: Kevin Wolf <address@hidden>
Reviewed-by: Michael Tokarev <address@hidden>
Tested-by: Michael Tokarev <address@hidden>
(cherry picked from commit a3548077062dd9dc2701ebffd931ba6eaef40bec)

Signed-off-by: Michael Roth <address@hidden>
---
 block/qcow2-refcount.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 5e3f915..96224d1 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -301,7 +301,8 @@ static int alloc_refcount_block(BlockDriverState *bs,
     uint64_t last_table_size;
     uint64_t blocks_clusters;
     do {
-        uint64_t table_clusters = size_to_clusters(s, table_size);
+        uint64_t table_clusters =
+            size_to_clusters(s, table_size * sizeof(uint64_t));
         blocks_clusters = 1 +
             ((table_clusters + refcount_block_clusters - 1)
             / refcount_block_clusters);
-- 
1.7.9.5