On Tue, Aug 06, 2013 at 09:40:42AM +0800, Fam Zheng wrote:
> We should never grow the stack beyond 1 MB, otherwise we'll fall off the
> end. Thread stacks and coroutine stacks (1 MB) do not grow.
> get_cluster_offset() allocates a big stack offset, it will fail for big
> cluster images, change to heap allocated buffer.
>
> Signed-off-by: Fam Zheng <f...@redhat.com>
> ---
> block/vmdk.c | 19 +++++++++++++------
> 1 file changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/block/vmdk.c b/block/vmdk.c
> index 3bcab26..21610e3 100644
> --- a/block/vmdk.c
> +++ b/block/vmdk.c
> @@ -842,16 +842,19 @@ static int get_whole_cluster(BlockDriverState *bs,
> uint64_t offset,
> bool allocate)
> {
> - /* 128 sectors * 512 bytes each = grain size 64KB */
> - uint8_t whole_grain[extent->cluster_sectors * 512];
> + int ret = VMDK_OK;
> + uint8_t *whole_grain = NULL;
>
> /* we will be here if it's first write on non-exist grain(cluster).
> * try to read from parent image, if exist */
> if (bs->backing_hd) {
> int ret;
^^^^^^
This above line should be removed; as it is this function will always return
VMDK_OK with this here, due to the scoping of this 'ret' inside the
if() block.
>
> + whole_grain =
> + qemu_blockalign(bs, extent->cluster_sectors << BDRV_SECTOR_BITS);
> if (!vmdk_is_cid_valid(bs)) {
> - return VMDK_ERROR;
> + ret = VMDK_ERROR;
> + goto exit;
> }
>
> /* floor offset to cluster */
> @@ -859,17 +862,21 @@ static int get_whole_cluster(BlockDriverState *bs,
> ret = bdrv_read(bs->backing_hd, offset >> 9, whole_grain,
> extent->cluster_sectors);
> if (ret < 0) {
> - return VMDK_ERROR;
> + ret = VMDK_ERROR;
> + goto exit;
> }
>
> /* Write grain only into the active image */
> ret = bdrv_write(extent->file, cluster_offset, whole_grain,
> extent->cluster_sectors);
> if (ret < 0) {
> - return VMDK_ERROR;
> + ret = VMDK_ERROR;
> + goto exit;
> }
> }
> - return VMDK_OK;
> +exit:
> + qemu_vfree(whole_grain);
> + return ret;
> }
>
> static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data)
> --
> 1.8.3.4
>
