Re: [PATCH v4 2/7] nbd/server: Plumb in new args to nbd_client_add()

["Daniel P. Berrangé" <berrange@redhat.com>]

On Wed, Aug 07, 2024 at 12:43:28PM -0500, Eric Blake wrote:
> Upcoming patches to fix a CVE need to track an opaque pointer passed
> in by the owner of a client object, as well as reequest for a time
> limit on how fast negotiation must complete.  Prepare for that by
> changing the signature of nbd_client_new() and adding an accessor to
> get at the opaque pointer, although for now the two servers
> (qemu-nbd.c and blockdev-nbd.c) do not change behavior.
> 
> Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> Signed-off-by: Eric Blake <eblake@redhat.com>
> ---
>  include/block/nbd.h | 11 ++++++++++-
>  blockdev-nbd.c      |  6 ++++--
>  nbd/server.c        | 20 +++++++++++++++++---
>  qemu-nbd.c          |  4 +++-
>  4 files changed, 34 insertions(+), 7 deletions(-)
> 
> diff --git a/include/block/nbd.h b/include/block/nbd.h
> index 4e7bd6342f9..5fe14786414 100644
> --- a/include/block/nbd.h
> +++ b/include/block/nbd.h
> @@ -33,6 +33,12 @@ typedef struct NBDMetaContexts NBDMetaContexts;
> 
>  extern const BlockExportDriver blk_exp_nbd;
> 
> +/*
> + * NBD_DEFAULT_HANDSHAKE_LIMIT: Number of seconds in which client must
> + * succeed at NBD_OPT_GO before being forcefully dropped as too slow.
> + */
> +#define NBD_DEFAULT_HANDSHAKE_LIMIT 10

Suggest

s/NBD_DEFAULT_HANDSHAKE_LIMIT/NBD_DEFAULT_HANDSHAKE_MAX_SECS/


> +
>  /* Handshake phase structs - this struct is passed on the wire */
> 
>  typedef struct NBDOption {
> @@ -403,9 +409,12 @@ AioContext *nbd_export_aio_context(NBDExport *exp);
>  NBDExport *nbd_export_find(const char *name);
> 
>  void nbd_client_new(QIOChannelSocket *sioc,
> +                    uint32_t handshake_limit,

s/handshake_limit/handshake_max_secs/

to make the units of the parameter self-documenting.

Since this is a non-functional suggestion

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


With regards,
Daniel
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