Re: [Qemu-devel] [PATCH 2/5] vhost-user: check unix_listen() return value

[Peter Maydell]

On Wed, 5 Jun 2019 at 16:02, Marc-André Lureau
<address@hidden> wrote:
>
> This check shouldn't be necessary, since &error_fatal is given as
> argument and will exit() on failure. However, this change should
> silence coverity CID 1401761 & 1401705.
>
> Signed-off-by: Marc-André Lureau <address@hidden>
> ---
>  contrib/vhost-user-gpu/main.c   | 4 ++++
>  contrib/vhost-user-input/main.c | 4 ++++
>  2 files changed, 8 insertions(+)
>
> diff --git a/contrib/vhost-user-gpu/main.c b/contrib/vhost-user-gpu/main.c
> index 9614c9422c..e0b6df5b4d 100644
> --- a/contrib/vhost-user-gpu/main.c
> +++ b/contrib/vhost-user-gpu/main.c
> @@ -1160,6 +1160,10 @@ main(int argc, char *argv[])
>
>      if (opt_socket_path) {
>          int lsock = unix_listen(opt_socket_path, &error_fatal);
> +        if (lsock < 0) {
> +            g_printerr("Failed to listen on %s.\n", opt_socket_path);
> +            exit(EXIT_FAILURE);
> +        }
>          fd = accept(lsock, NULL, NULL);
>          close(lsock);
>      } else {
> diff --git a/contrib/vhost-user-input/main.c b/contrib/vhost-user-input/main.c
> index 8d493f598e..8b854117f5 100644
> --- a/contrib/vhost-user-input/main.c
> +++ b/contrib/vhost-user-input/main.c
> @@ -367,6 +367,10 @@ main(int argc, char *argv[])
>
>      if (opt_socket_path) {
>          int lsock = unix_listen(opt_socket_path, &error_fatal);
> +        if (lsock < 0) {
> +            g_printerr("Failed to listen on %s.\n", opt_socket_path);
> +            exit(EXIT_FAILURE);
> +        }
>          fd = accept(lsock, NULL, NULL);
>          close(lsock);
>      } else {
> --
> 2.22.0.rc2.384.g1a9a72ea1d
>

Maybe better to just assert(lsock >= 0) ?
(I hadn't noticed the &error_fatal -- it means this new code
is unreachable.)

thanks
-- PMM