strcpm () это не дает мне равных

Question

Я пытаюсь получить буфер от пользователя, и когда буфер равен 00 B или 00 W, он переходит в оператор if, но по какой-то причине буфер оказывается больше 0. Я распечатал, какой буфер и это 00 B или 00 W при запросе. Почему это?? Я сравниваю не то?

ssize_t chess_write(struct file *pfile, const char __user *buffer, size_t length, loff_t *offset)
{
    int black;
    int white;

    sprintf(msg, "%s(%zu letters)", buffer, length);
    msg_size = strlen(msg);

    LOG_INFO("In function %s\n", __FUNCTION__);

    LOG_INFO("buffer test in write %s", buffer);    

    black = strcmp(buffer, "00 B");
    white = strcmp(buffer, "00 W");
        if (black == 0)
        {
            LOG_INFO("Chess: Initiate chess as black pieces\n");
        }
        else if (black < 0)
        {
            LOG_INFO("Chess: black is less than 0\n");
        }
        else if (black > 0)
        {
            LOG_INFO("Chess: black is greater than 0\n");
        }
        else if (white == 0)
        {
            LOG_INFO("Chess: Initiate chess as white pieces\n");
        }

    LOG_INFO("Chess: Wrote %zu characters from the user\n", length);
    return length; // return bytes wrote
}

Результат, который я получаю, это

[Apr29 18:58] [chess] Module Started
[  +0.000005] [chess] Device class resgistered correctly
[  +0.000077] [chess] Device created correctly
[  +3.632050] [chess] In function chess_open
[  +0.000706] [chess] In function chess_write
[Apr29 19:00] [chess] In function chess_write
[  +0.000003] [chess] buffer test in write 00 B
[  +0.000001] [chess] Chess: black is greater than 0
[  +0.000001] [chess] Chess: Wrote 5 characters from the user
[  +0.001368] [chess] In function chess_read
[  +0.000002] [chess] buffer test in read 00 B
              (5 letters)
[  +0.000001] [chess] Chess: black is greater than 0
[  +0.000002] [chess] Chess: Read 16 characters to the user
[  +0.002089] [chess] In function chess_write
[  +0.000002] [chess] buffer test in write 01
[  +0.000000] [chess] Chess: black is greater than 0
[  +0.000001] [chess] Chess: Wrote 3 characters from the user
[  +0.007073] [chess] In function chess_read
[  +0.000001] [chess] buffer test in read 01
              (3 letters)
[  +0.000001] [chess] Chess: black is greater than 0
[  +0.000001] [chess] Chess: Read 14 characters to the user

Ps. Я работаю с LOG_INFO в другом файле

#define _CONFIG_PRINTK(once, level, fmt, ...)                       \
    do{                                     \
        printk##once(KERN_##level "[" MODULE_NAME "] " fmt,     \
                ##__VA_ARGS__);                 \
    } while(0)

#define LOG_INFO(format, ...) _CONFIG_PRINTK(, INFO, format, ##__VA_ARGS__)

#define LOG_WARNING(format, ...) _CONFIG_PRINTK(, WARNING, format, ##__VA_ARGS__)

#define LOG_ERROR(format, ...) _CONFIG_PRINTK(, ERR, format, ##__VA_ARGS__)