Yi Liu <[email protected]> writes:
[...]
> +static int vfio_get_devicefd(const char *sysfs_path, Error **errp)
> +{
> + long int ret = -ENOTTY;
> + char *path, *vfio_dev_path = NULL, *vfio_path = NULL;
> + DIR *dir;
> + struct dirent *dent;
> + gchar *contents;
> + struct stat st;
> + gsize length;
> + int major, minor;
> + dev_t vfio_devt;
> +
> + path = g_strdup_printf("%s/vfio-device", sysfs_path);
> + if (stat(path, &st) < 0) {
> + error_setg_errno(errp, errno, "no such host device");
> + goto out_free_path;
> + }
> +
> + dir = opendir(path);
> + if (!dir) {
> + error_setg_errno(errp, errno, "couldn't open dirrectory %s", path);
> + goto out_free_path;
> + }
> +
> + while ((dent = readdir(dir))) {
> + if (!strncmp(dent->d_name, "vfio", 4)) {
> + vfio_dev_path = g_strdup_printf("%s/%s/dev", path, dent->d_name);
> + break;
> + }
> + }
> +
> + if (!vfio_dev_path) {
> + error_setg(errp, "failed to find vfio-device/vfioX/dev");
> + goto out_free_path;
> + }
> +
> + if (!g_file_get_contents(vfio_dev_path, &contents, &length, NULL)) {
> + error_setg(errp, "failed to load \"%s\"", vfio_dev_path);
> + goto out_free_dev_path;
> + }
> +
> + if (sscanf(contents, "%d:%d", &major, &minor) != 2) {
> + error_setg(errp, "failed to get major:mino for \"%s\"",
> vfio_dev_path);
> + goto out_free_dev_path;
> + }
> + g_free(contents);
> + vfio_devt = makedev(major, minor);
> +
> + vfio_path = g_strdup_printf("/dev/vfio/devices/%s", dent->d_name);
> + ret = open_cdev(vfio_path, vfio_devt);
> + if (ret < 0) {
> + error_setg(errp, "Failed to open %s", vfio_path);
> + }
> +
> + trace_vfio_iommufd_get_devicefd(vfio_path, ret);
> + g_free(vfio_path);
> +
> +out_free_dev_path:
> + g_free(vfio_dev_path);
> +out_free_path:
> + g_free(path);
> +
> + if (*errp) {
> + error_prepend(errp, VFIO_MSG_PREFIX, path);
I ran into this while trying to get things running, so haven't reviewed
the patch but noticed path is used after it's freed if !!*errp.
- Alistair
> + }
> + return ret;
> +}