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我想使用 mprotect() 拦截对我的应用程序中特定内存块的所有内存引用，所以我稍微修改了此处找到的 mprotect 示例代码。但是，当我运行修改后的代码时，应用程序不会在捕获的第一个异常之后继续前进。相反，Linux 将继续向我的应用程序发送异常，并且我的应用程序将继续在无限循环中打印出同一行。

现在，我的问题是如何告诉 Linux 继续前进并进入下一条指令。

以下是输出示例：

Got SIGSEGV at address: 0x1556000
value of i is: 8192
Got SIGSEGV at address: 0x1556000
value of i is: 8192
/* Infinitely repeats the above two messages. */

这是代码：

#include <unistd.h>
#include <signal.h>
#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/mman.h>

#define handle_error(msg) \
    do { perror(msg); exit(EXIT_FAILURE); } while (0)

char *buffer;
int i;

static void handler(int sig, siginfo_t *si, void *unused)
{
    printf("Got SIGSEGV at address: 0x%lx\nvalue of i is: %d\n",
            (long) si->si_addr, i);
   //exit(EXIT_FAILURE);
}

int
main(int argc, char *argv[])
{
    char *p;
    int pagesize;
    struct sigaction sa;


    sa.sa_flags = SA_SIGINFO;
    sigemptyset(&sa.sa_mask);
    sa.sa_sigaction = handler;
    if (sigaction(SIGSEGV, &sa, NULL) == -1)
        handle_error("sigaction");

    pagesize = sysconf(_SC_PAGE_SIZE);
    if (pagesize == -1)
        handle_error("sysconf");

    /* Allocate a buffer aligned on a page boundary;
    initial protection is PROT_READ | PROT_WRITE */

    buffer = memalign(pagesize, 4 * pagesize);
    if (buffer == NULL)
        handle_error("memalign");

    printf("Start of region:        0x%lx\n", (long) buffer);

    if (mprotect(buffer + pagesize * 2, pagesize, PROT_READ) == -1)
        handle_error("mprotect");


    //for (p = buffer, i = 0 ; i < 10 ; ++i )
    //  *(p++) = 'a';

    for (p = buffer ; i< 8200; ++i )
        *(p++) = 'a';

    printf("Loop completed\n");     /* Should never happen */
    exit(EXIT_SUCCESS);
}
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