> +static int tap_parse_fds_and_queues(const NetdevTapOptions *tap, int **fds,
> + Error **errp)
> +{
> + unsigned queues;
> +
> + if (tap->has_queues + !!tap->helper + !!tap->fds + !!tap->fd > 1) {
> + error_setg(errp, "queues=, helper=, fds= and fd= are mutual
> exclusive");
> + return -1;
> + }
> +
> + if (tap->has_queues) {
> + if (tap->queues > INT_MAX) {
> + error_setg(errp, "queues exceeds maximum %d", INT_MAX);
> + return -1;
> + }
> + queues = tap->queues;
> + *fds = NULL;
> + } else if (tap->fd || tap->fds) {
> + queues = net_parse_fds(tap->fd ?: tap->fds, fds,
> + tap->fd ? 1 : 0, errp);
> + if (!*fds) {
> + return -1;
> + }
> + } else if (tap->helper) {
> + int fd = net_bridge_run_helper(tap->helper,
> + tap->br ?: DEFAULT_BRIDGE_INTERFACE,
> + errp);
> + if (fd < 0) {
> + return -1;
> + }
> +
> + queues = 1;
> + *fds = g_new(int, 1);
> + **fds = fd;
> + }
> +
> + if (*fds && !unblock_fds(*fds, queues, errp)) {
> + net_free_fds(*fds, queues);
> + return -1;
> + }
> +
> + return queues;
> +}
This causes a build error in my environment:
../net/tap.c: In function 'net_init_tap':
../net/tap.c:901:12: error: 'queues' may be used uninitialized in this function
[-Werror=maybe-uninitialized]
901 | return queues;
| ^~~~~~
../net/tap.c:863:14: note: 'queues' was declared here
863 | unsigned queues;
| ^~~~~~
Looking at the code is seems like it would be possible for queues to be unset
If !has_queues && !tap->fd && !tap->fds && !tap->helper
Can we default to queues = 1, or if that isn't appropriate add an else block
that prints an error and returns -1?
Thanks,
Ben
