static ssize_t local_preadv(FsContext *ctx, V9fsFidOpenState *fs,
                            const struct iovec *iov,
                            int iovcnt, off_t offset)
{
#ifdef CONFIG_PREADV
    return preadv(fs->fd, iov, iovcnt, offset);
#else
    int err = lseek(fs->fd, offset, SEEK_SET);
    if (err == -1) {
        return err;
    } else {
        return readv(fs->fd, iov, iovcnt);
    }
#endif
}

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.