File: qcow2-fix-refcount-table-size-calculation.patch

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From 9395e8b4c5d57aab8fe60e0a73a1e558c3f3b691 Mon Sep 17 00:00:00 2001
From: Kevin Wolf <kwolf@redhat.com>
Date: Fri, 26 Oct 2012 16:33:32 +0200
Subject: qcow2: Fix refcount table size calculation
Bug-Debian: http://bugs.debian.org/691569

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 <kwolf@redhat.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
(cherry picked from commit a3548077062dd9dc2701ebffd931ba6eaef40bec)

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
---
 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 443c021..645c7c5 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);
-- 
1.7.10.4