[v1] block: Follow-up for .bdrv_co_create (part 1)

[Qemu-devel] [PATCH for-2.12 11/12] vhdx: Check for 4 GB maximum log size on creation

Posted by Kevin Wolf 7 years, 7 months ago

It's unclear what the real maximum is, but we use an uint32_t to store
the log size in vhdx_co_create(), so we should check that the given
value fits in 32 bits.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/vhdx.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/block/vhdx.c b/block/vhdx.c
index 0e48179b81..a1a0302799 100644
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -1829,6 +1829,10 @@ static int coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts,
     if (!vhdx_opts->has_log_size) {
         log_size = DEFAULT_LOG_SIZE;
     } else {
+        if (vhdx_opts->log_size > UINT32_MAX) {
+            error_setg(errp, "Log size must be smaller than 4 GB");
+            return -EINVAL;
+        }
         log_size = vhdx_opts->log_size;
     }
     if (log_size < MiB || (log_size % MiB) != 0) {
-- 
2.13.6

Re: [Qemu-devel] [PATCH for-2.12 11/12] vhdx: Check for 4 GB maximum log size on creation

Posted by Eric Blake 7 years, 7 months ago

On 03/20/2018 12:36 PM, Kevin Wolf wrote:
> It's unclear what the real maximum is, but we use an uint32_t to store
> the log size in vhdx_co_create(), so we should check that the given
> value fits in 32 bits.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>   block/vhdx.c | 4 ++++
>   1 file changed, 4 insertions(+)

Reviewed-by: Eric Blake <eblake@redhat.com>

> 
> diff --git a/block/vhdx.c b/block/vhdx.c
> index 0e48179b81..a1a0302799 100644
> --- a/block/vhdx.c
> +++ b/block/vhdx.c
> @@ -1829,6 +1829,10 @@ static int coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts,
>       if (!vhdx_opts->has_log_size) {
>           log_size = DEFAULT_LOG_SIZE;
>       } else {
> +        if (vhdx_opts->log_size > UINT32_MAX) {
> +            error_setg(errp, "Log size must be smaller than 4 GB");
> +            return -EINVAL;
> +        }
>           log_size = vhdx_opts->log_size;
>       }
>       if (log_size < MiB || (log_size % MiB) != 0) {
> 

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

Re: [Qemu-devel] [PATCH for-2.12 11/12] vhdx: Check for 4 GB maximum log size on creation

Posted by Jeff Cody 7 years, 7 months ago

On Tue, Mar 20, 2018 at 06:36:31PM +0100, Kevin Wolf wrote:
> It's unclear what the real maximum is, but we use an uint32_t to store
> the log size in vhdx_co_create(), so we should check that the given
> value fits in 32 bits.
> 

It's a uint32 in the on-disk header per spec, so I agree the implied max is
UINT32_MAX

Reviewed-by: Jeff Cody <jcody@redhat.com>

> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  block/vhdx.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/block/vhdx.c b/block/vhdx.c
> index 0e48179b81..a1a0302799 100644
> --- a/block/vhdx.c
> +++ b/block/vhdx.c
> @@ -1829,6 +1829,10 @@ static int coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts,
>      if (!vhdx_opts->has_log_size) {
>          log_size = DEFAULT_LOG_SIZE;
>      } else {
> +        if (vhdx_opts->log_size > UINT32_MAX) {
> +            error_setg(errp, "Log size must be smaller than 4 GB");
> +            return -EINVAL;
> +        }
>          log_size = vhdx_opts->log_size;
>      }
>      if (log_size < MiB || (log_size % MiB) != 0) {
> -- 
> 2.13.6
>