Re: [Qemu-devel] [PATCH] vmdk: Widen before shifting 32 bit header field

[John Snow]

On 04/27/2015 10:23 AM, Fam Zheng wrote:
> Coverity spotted this.
>
> The field is 32 bits, but if it's possible to overflow in 32 bit
> left shift.
>
> Signed-off-by: Fam Zheng <address@hidden>
> ---
>   block/vmdk.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/block/vmdk.c b/block/vmdk.c
> index 8410a15..d72a6e8 100644
> --- a/block/vmdk.c
> +++ b/block/vmdk.c
> @@ -523,7 +523,7 @@ static int vmdk_open_vmfs_sparse(BlockDriverState *bs,
>       }
>       ret = vmdk_add_extent(bs, file, false,
>                             le32_to_cpu(header.disk_sectors),
> -                          le32_to_cpu(header.l1dir_offset) << 9,
> +                          (int64_t)le32_to_cpu(header.l1dir_offset) << 9,
>                             0,
>                             le32_to_cpu(header.l1dir_size),
>                             4096,

Reviewed-by: John Snow <address@hidden>