[Qemu-devel] [PATCH EMBARGOED 5/7] vmdk: check cluster size in vmdk_open

[Fam Zheng <famz@redhat.com>]

VMDK specification doesn't give upper limit of cluster size
(header.grainSize). But we need to avoid unbounded memory allocation.
Check the value when opening and refuse too big value (>512MB cluster
size).

Signed-off-by: Fam Zheng <famz@redhat.com>
---
 block/vmdk.c               | 1 +
 tests/qemu-iotests/059     | 2 +-
 tests/qemu-iotests/059.out | 6 ++++++
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/block/vmdk.c b/block/vmdk.c
index dbedff7..1d6bc39 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -41,6 +41,7 @@
 #define VMDK4_GD_AT_END 0xffffffffffffffffULL
 
 #define VMDK_GTE_ZEROED 0x1
+#define VMDK_GRANULARITY_MAX 0x100000 /* limit of cluster_sectors */
 
 /* VMDK internal error codes */
 #define VMDK_OK      0
diff --git a/tests/qemu-iotests/059 b/tests/qemu-iotests/059
index 18807d3..f14c41b 100755
--- a/tests/qemu-iotests/059
+++ b/tests/qemu-iotests/059
@@ -43,7 +43,7 @@ _supported_fmt vmdk
 _supported_proto generic
 _supported_os Linux
 
-granularity_offset=16
+granularity_offset=20
 
 echo "=== Testing invalid granularity ==="
 echo
diff --git a/tests/qemu-iotests/059.out b/tests/qemu-iotests/059.out
index 4ca7f29..380ca3d 100644
--- a/tests/qemu-iotests/059.out
+++ b/tests/qemu-iotests/059.out
@@ -1,2 +1,8 @@
 QA output created by 059
+=== Testing invalid granularity ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+invalid granularity, image may be corrupt
+qemu-io: can't open device TEST_DIR/t.vmdk
+no file open, try 'help open'
 *** done
-- 
1.8.3.4