[v2,1/1] block/parallels: check new image size
diff mbox

Message ID 1469639300-12155-1-git-send-email-den@openvz.org
State New
Headers show

Commit Message

Denis V. Lunev July 27, 2016, 5:08 p.m. UTC
From: Klim Kireev <proffk@virtuozzo.mipt.com>

Before this patch incorrect image could be created via qemu-img
(Example: qemu-img create -f parallels -o size=4096T hack.img),
incorrect images cannot be used due to overflow in main image structure.

This patch add check of size in image creation.

After reading size it compare it with UINT32_MAX * cluster_size.

Signed-off-by: Klim Kireev <proffk@virtuozzo.mipt.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
---
changes from v1:
- fixed from: to be virtuozzo.mipt.com to match Signed-off-by

 block/parallels.c | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Stefan Hajnoczi July 29, 2016, 2:09 p.m. UTC | #1
On Wed, Jul 27, 2016 at 08:08:20PM +0300, Denis V. Lunev wrote:
> From: Klim Kireev <proffk@virtuozzo.mipt.com>
> 
> Before this patch incorrect image could be created via qemu-img
> (Example: qemu-img create -f parallels -o size=4096T hack.img),
> incorrect images cannot be used due to overflow in main image structure.
> 
> This patch add check of size in image creation.
> 
> After reading size it compare it with UINT32_MAX * cluster_size.
> 
> Signed-off-by: Klim Kireev <proffk@virtuozzo.mipt.com>
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> CC: Stefan Hajnoczi <stefanha@redhat.com>
> ---
> changes from v1:
> - fixed from: to be virtuozzo.mipt.com to match Signed-off-by
> 
>  block/parallels.c | 5 +++++
>  1 file changed, 5 insertions(+)

Thanks, applied to my block tree:
https://github.com/stefanha/qemu/commits/block

Stefan

Patch
diff mbox

diff --git a/block/parallels.c b/block/parallels.c
index 807a801..a0bc95b 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -43,6 +43,7 @@ 
 #define HEADER_MAGIC2 "WithouFreSpacExt"
 #define HEADER_VERSION 2
 #define HEADER_INUSE_MAGIC  (0x746F6E59)
+#define MAX_PARALLELS_IMAGE_FACTOR (1ull << 32)
 
 #define DEFAULT_CLUSTER_SIZE 1048576        /* 1 MiB */
 
@@ -475,6 +476,10 @@  static int parallels_create(const char *filename, QemuOpts *opts, Error **errp)
                           BDRV_SECTOR_SIZE);
     cl_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE,
                           DEFAULT_CLUSTER_SIZE), BDRV_SECTOR_SIZE);
+    if (total_size >= MAX_PARALLELS_IMAGE_FACTOR * cl_size) {
+        error_propagate(errp, local_err);
+        return -E2BIG;
+    }
 
     ret = bdrv_create_file(filename, opts, &local_err);
     if (ret < 0) {