Re: [PATCH v2] net/tap: Set return code on failure

[Stefano Garzarella]

On Wed, Jan 05, 2022 at 08:42:14AM -0800, Patrick Venture wrote:
> From: Peter Foley <pefoley@google.com>
>
> Match the other error handling in this function.
>
> Fixes: e7b347d0bf6 ("net: detect errors from probing vnet hdr flag for TAP 
> devices")
>
> Reviewed-by: Patrick Venture <venture@google.com>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Signed-off-by: Peter Foley <pefoley@google.com>
> ---
> v2: Fixed commit titlewq and updated description.
> ---
> net/tap.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/net/tap.c b/net/tap.c
> index f716be3e3f..c5cbeaa7a2 100644
> --- a/net/tap.c
> +++ b/net/tap.c
> @@ -900,6 +900,7 @@ int net_init_tap(const Netdev *netdev, const char *name,
>             if (i == 0) {
>                 vnet_hdr = tap_probe_vnet_hdr(fd, errp);
>                 if (vnet_hdr < 0) {
> +                    ret = -1;

In case of error, `vnet_hdr` should contain an error code (negative), so 
we could assign `ret = vnet_hdr`, but looking at the implementation of 
tap_probe_vnet_hdr(), in case of error it returns just -1, so it's ok 
too:

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>