This replaces two "time(NULL)" invocations with "g_random_int()".
According to VMDK spec, CID "is a random 32‐bit value updated the first
time the content of the virtual disk is modified after the virtual disk
is opened". Using "seconds since epoch" is just a "lame way" to generate
it, and not completely safe because of the low precision.
Suggested-by: Markus Armbruster <arm...@redhat.com>
Signed-off-by: Fam Zheng <f...@redhat.com>
Reviewed-by: Markus Armbruster <arm...@redhat.com>
---
block/vmdk.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/block/vmdk.c b/block/vmdk.c
index 2cbfd3e..ebb4b70 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -28,6 +28,7 @@
#include "qemu/module.h"
#include "migration/migration.h"
#include <zlib.h>
+#include <glib.h>
#define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D')
#define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V')
@@ -1538,7 +1539,7 @@ static int vmdk_write(BlockDriverState *bs, int64_t
sector_num,
/* update CID on the first write every time the virtual disk is
* opened */
if (!s->cid_updated) {
- ret = vmdk_write_cid(bs, time(NULL));
+ ret = vmdk_write_cid(bs, g_random_int());
if (ret < 0) {
return ret;
}
@@ -1922,7 +1923,7 @@ static int vmdk_create(const char *filename, QemuOpts
*opts, Error **errp)
}
/* generate descriptor file */
desc = g_strdup_printf(desc_template,
- (uint32_t)time(NULL),
+ g_random_int(),
parent_cid,
fmt,
parent_desc_line,
--
1.9.3
