check for bs->drv in bdrv_flush (Christoph Hellwig)

All the bdrv_ helpers should check for bs->drv being zero as that means
there is no backend image open.  bdrv_flush fails to perform that check
and can thus cause NULL pointer dereferences.

Found using qemu-io.


Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6943 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aliguori 2009-03-29 01:31:51 +00:00
parent 999dec57f6
commit 081501dace

View File

@ -1002,6 +1002,8 @@ const char *bdrv_get_device_name(BlockDriverState *bs)
void bdrv_flush(BlockDriverState *bs)
{
if (!bs->drv)
return;
if (bs->drv->bdrv_flush)
bs->drv->bdrv_flush(bs);
if (bs->backing_hd)