Re: [Qemu-trivial] [PATCH] filter-mirror: segfault when specifying non existent device

[Zhang Chen]

On 08/21/2017 11:50 PM, Eduardo Otubo wrote:
> When using filter-mirror like the example below where the interface
> 'ndev0' does not exist on the host, QEMU crashes into segmentation
> fault.
>
>   $ qemu-system-x86_64 -S -machine pc -netdev user,id=ndev0 -object 
> filter-mirror,id=test-object,netdev=ndev0
>
> This happens because the function filter_mirror_setup() does not checks
> if the device actually exists and still keep on processing calling
> qemu_chr_find(). This patch fixes this issue.
>
> Signed-off-by: Eduardo Otubo <address@hidden>

Looks good for me.

Reviewed-by: Zhang Chen<address@hidden>

Thanks
Zhang Chen

> ---
>   net/filter-mirror.c | 14 +++++++++++---
>   1 file changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/net/filter-mirror.c b/net/filter-mirror.c
> index 90e2c92337..e18a4b16a0 100644
> --- a/net/filter-mirror.c
> +++ b/net/filter-mirror.c
> @@ -213,14 +213,22 @@ static void filter_mirror_setup(NetFilterState *nf, Error 
> **errp)
>       MirrorState *s = FILTER_MIRROR(nf);
>       Chardev *chr;
>   
> +    if (s->outdev == NULL) {
> +        goto err;
> +    }
> +
>       chr = qemu_chr_find(s->outdev);
> +
>       if (chr == NULL) {
> -        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
> -                  "Device '%s' not found", s->outdev);
> -        return;
> +        goto err;
>       }
>   
>       qemu_chr_fe_init(&s->chr_out, chr, errp);
> +
> +err:
> +    error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, "Device '%s' not found",
> +              nf->netdev_id);
> +    return;
>   }
>   
>   static void redirector_rs_finalize(SocketReadState *rs)

--
Thanks
Zhang Chen