История изменений

DECLARE_WAIT_QUEUE_HEAD(wq);
static int finished;

unsigned long **sys_call_table;
while (finished != 1)
asmlinkage long (*ref_sys_write) (unsigned int fd, const char __user * buf, size_t count);

asmlinkage long new_sys_write(unsigned int fd, const char __user * buf, size_t count)
{
        finished = 0;
// тут я вызываю настоящий вызов, чтобы после проанализировать его результат.

        long k = ref_sys_write(fd, buf, count);

        MyAnalyzeFunc(k, count);

        finished = 1;
        wake_up_interruptible(&wq);

        return k;

}

static int __init interceptor_start(void)
{

        disable_page_protection();

        ref_sys_write = (void *)sys_call_table[__NR_write];

        sys_call_table[__NR_write] = (unsigned long *)new_sys_write;

        enable_page_protection();


        return 0;

}

static void __exit interceptor_end(void)
{

        if (!sys_call_table)
                return;

        wait_event_interrutible(wq, finished != 0);

        disable_page_protection();

        sys_call_table[__NR_write] = (unsigned long *)ref_sys_write;

        enable_page_protection();

}

module_init(interceptor_start);

module_exit(interceptor_end);

DECLARE_WAIT_QUEUE_HEAD(wq);
static int finished;

unsigned long **sys_call_table;

asmlinkage long (*ref_sys_write) (unsigned int fd, const char __user * buf, size_t count);

asmlinkage long new_sys_write(unsigned int fd, const char __user * buf, size_t count)
{
        finished = 0;
// тут я вызываю настоящий вызов, чтобы после проанализировать его результат.

        long k = ref_sys_write(fd, buf, count);

        MyAnalyzeFunc(k, count);

        finished = 1;
        wake_up_interruptible(&wq);

        return k;

}

static int __init interceptor_start(void)
{

        disable_page_protection();

        ref_sys_write = (void *)sys_call_table[__NR_write];

        sys_call_table[__NR_write] = (unsigned long *)new_sys_write;

        enable_page_protection();


        return 0;

}

static void __exit interceptor_end(void)
{

        if (!sys_call_table)
                return;

        wait_event_interrutible(wq, finished != 0);

        disable_page_protection();

        sys_call_table[__NR_write] = (unsigned long *)ref_sys_write;

        enable_page_protection();

}

module_init(interceptor_start);

module_exit(interceptor_end);